The boundaries that Dirac violated in his prediction of antimatter include time, gravity, and conscious observation. If antimatter exists in anti-time, then the bulk that was created during the big bang could exist before the big bang. 😮
To answer the question "Does it matter?" you just need to also ask the question "Does it antimatter?" The two questions then annihilate and leave you with no problem.
I am calling the Nobel Prize committee to immediately throw out all the other names nominated so far and to close the submission for the next,..., say century?
Not gonna lie, any time someone on a video says "imagine you're..." I always go 'ok wait....[look into distance with my hand up, then slowy point at screen] ...okay got it!' Yes, I am a blast at parties. I think....never been to one....
i once had a dream where a farmer got super famous because he figured out how to grow an anti-onion. So I think it would be pretty cool if physicists got to work on doing that
what bothers me the most about relativistic space travel is that shielding is never discussed. when you're going that fast, every little spec of dust in your way becomes a relativistic impactor that cannot be deflected and leaves a good-size crater in your ship
Collisions are very different at differing energy scales. A bit of dust hitting at relativistic speed won't make a crater, it will instead act like a cosmic ray (because that's exactly what a cosmic rays is). You need radiation shielding for protection. Hydrogen fuel makes great radiation shielding, and you'll have a lot that, so it's not a big deal as long as you plan for it. You'll need quite powerful radar and lasers to take out larger bits of matter though - good thing you have an enormously powerful fuel source, or that would be a totally unworkable amount of energy.
@@SkorjOlafsen What would act like cosmic rays is relativistic gas, not dust. A 0.1 mg speck of dust at 0.3 c has 434 MJ kinetic energy, or about 100 kg of TNT, concentrated on a very small object. It would definitely leave a crater. At typical rock density and as a sphere, the cross section of that speck is a miniscule 0.125 mm^2, and it's got so much momentum that it would have to begin being stopped for so long, and thus so far away, that there's just no hope of detecting it and aiming a laser at it (plus beam divergence is a thing). And this would be for _every_ speck of dust.
@@orthoplex64 You would get a crater that was large relative to the size of a speck of dust, but only a tiny portion of the collision energy can be dissipated that way (through creating plasma at the impact point, which then creates a crater). Once the electrons of the impactor are ionized away, creating a small crater as a side effect, the nucleons keep going until there's a direct collision with (usually) protons of the ship, which then make a particle shower depending on just how relativistic we're talking about. So the energy of impact is mostly transferred deep in the target, not as a surface crater. Effective shielding requires a deep pool of proton-dense material, such as water or liquid hydrogen. The larger the ship, the less of a problem this is. Ice makes the best shielding, since it can't flow out through all the little holes that will accumulate, but a fuel tank that's actively being drained to run the engines works too. Shielding a tiny probe seems impractical, but for a large ship with millions (or billions) of tons of fuel, it's just en engineering consideration among many. And unless we find some way to make grams of antimatter, millions of tons of fuel is the scale needed for a small payload.
I mean in sci-fi it’s solved by whatever gravity generator or shielding that exists within the universe. The only other solution ever brought up would be a SIM hull which would maybe be indestructible so therefore it’s not an issue.
The Expanse is the only space Sci-Fi show/book series that I know of which dealt with the need to decelerate in space travel. Everywhere they went they had to do a "flip and burn" procedure to decelerate toward their destination. But of course, they had SUPER efficient Fusion reactor main thrusters that allowed them to continuously accelerate and decelerate (also giving them thrust gravity as a bonus). Still, closest to realistic space travel I've seen... in sci-fi that is.
Lost Fleet not only takes the need to decelerate seriously, it also extensively considers the problems relativity would cause for warships attempting to intercept and fight each other at relativistic speeds. Plus light lag. Ex: In the series, targeting systems simply can’t adjust for the distorted view of the outside universe if the merging speed of the two ships exceeds 0.2c. The series even gets down to considering physical computing limits (such as: information in a computer, no matter how powerful, cannot itself exceed light speed, so you run up against limits on how quickly certain things could possibly react, etc).
You know what I love the most about these videos? Angela just seems so *done* with everything. Not in a bad way, more like a "look, hear me out, OK?" -- I almost want to say "Thank you for putting up with all the dumb stuff"
It's fine. Yeah I sense Angela is in a near constant state of exasperation. It seems to be one of her motivations to dig into something, then motivates her to communicate it. Yeah, I like that a lot. I could imagine listening to her for hours and hours as she explains, intersperses her thoughts with research, adds social commentary, and goes off on tangents. If I were wealthy I'd pay for the privilege. Just happy she likes making free youtube videos. ...cheshire smile and double thumbs up.
Nothing is more frustrating than thinking someone is interested in a topic and then finding out that they are actually interested in a pseudoscience that's loosely based on said topic.
"Why do they annihilate?" "Feynman" "But, why do they annihilate?" I already know this is gonna be a banger video LMFAO. You're so good at this type of humour
But do they? 95% of matter is 'dark' and +ve + -ve matter = neutral, more massive so also more compact matter = DARK... The magimatical fudge-packed Standard Model is a complete joke compared to this realist piss-take, or something much like it. Liberal Wasters can't understand the Conservative Universe. -- Electro-Positronic Field: -ve gas binds a ball of +ve cells freed by Full Escape Energy as electron-positron pairs Spin: particles pull gas in straight/pump out spirals at 90'. Motion increases gas intake, biasing spin at 90' Magnetism: spin flows straight to a neighbour. Gravity, energy conservation, field balance preservation cause circuits Mass: gas acceleration drags cells further apart inwardly but closer laterally. +ve shells, -ve gaps, packed core Gravity: like mass but slower acceleration with drag on field cells cancelled by dark energy so cells remain equidistant Dark Energy: more gas near mass shrinks field, expanded by less in voids + new matter creation / black hole growth Heavy Force: mass multiplier mechanism pulls in field before annihilating all heavy composite cored particles but protons Heavy Fusion: in the Big Bang (and stars?) 2 positrons oppositely hit 1 electron (more than 2 electrons hit 1 positron) Antimatter: 1,2 e_p pairs annihilate. 3: proton+anti proton or muon+anti muon. 4: neutron+anti neutron. 5: tau+anti tau Positronium: e_p. Muon: ep_e. Proton: pep. Neutron: pep_e. Tau: epep_e. Neutron mass is halfway between muon and tau Lifetime: heavy force starts when (anti) muons/taus slow from C. Electric force speed (C) and Time slow with gas density Beta- Decay: pep_e => pep e. Beta+: pep + new e_p => pep_e p. Weak Force: unstable atoms form and annihilate e_p pairs Nuclear Force: neutron electrons bond to protons. Mass and magnetism compact and strengthen the nucleus Black Hole: atoms cut into neutrons fused as tau cores (epep). Field spins, time slows, core annihilates, no singularity Dark Matter: (anti) muons/taus last longer as the galaxy thins out? Solitary (anti) muon/tau cores? 'black hole spin'? Photon: compressed, concentrated gas wave core pulls in field cells as it passes. Field warps diffract and interfere 2 Slit Experiment: photon/particle field warps diffract and interfere, guiding the core. Detectors interfere with guides Entanglement: correlation broken by measurement? Physical link? FTL base electric force, annihilation only in black holes Entropy Law: Work can add complexity that tends towards simplicity without work being done
The secret KSP method to slowing down is lithobraking, but that's not really an option unless you've engaged into a war across some very long distances.
if you're approaching a planet at 0.3 C you can just toggle the x10 000 timewarp and clip through the ground, leaving the other side of the planet at 0.5 C.
Timestamps: Intro: 0:00 How antimatter was discovered: 3:00 where is all the antimatter?: 10:50 making antimatter with science: 17:00 p + p ---> p + p + π^0: 20:42 p + p ---> p + p + p + p̅ : 26:09 antimatter factories: 34:42 why do they annihilate: 39:10 feynman: 40:54 but, why do they annihilate?: 45:49 antimatter as propulsion: 49:15 the patrons: 1:04:15 slowing down in space: 1:04:47
4:00 : ME: "Oh, hey! I'll pause the video and solve the equation. I come up with ..." "... 2-and-a-half seconds." 4:26 : VIDEO : "That initial velocity you threw the ball down with, 8 meters per second, --" ME: "WHAT?! Initial velocity?! Gawds dammit!"
yes, that should be 2.5 seconds. where did that initial velocity appeared from ? Why dY = 30m and then that same dY = -30m ? Why make simple calculations complex for no reason?
I love your sense of humor, and I love that you're so dang smart, and I love that you're such a good explainer, but there's something else too... I graduated with a major in physics from a large Midwestern university in 1974. In my four years there, there was only one female student in any physics class during that entire time (coincidentally, she was from my high school, and yes, she completed her major). It is such a joy now 50 years later to see brilliant young women like you and Dr. Becky showing other young women that yes, you can do science and you can do math. Sadly, women have been doing this for decades (centuries? See Madame Curie) but they rarely received the recognition they were due, or their work was flat out stolen. Where will we be in another 50 years? Maybe you'll have invented a working time machine by then. :-)
It turns out you can design a lot of cool technology if you never ask "but where do the batteries go." I'm getting flashbacks to my highschool Physics AP class where my group was assigned to explain the technology that Syndrome uses in The Incredibles. (It was a fun project.) We quickly determined that antimatter was the only way to get a high enough energy density for most of his technology to work, and that at current antimatter production rates it would take longer than the age of the universe to make enough for his flight in the film.
"okay so... all you do is just get a big box, right, and put like 83.2 thousand quintillion AAA batteries in it connected up and..." - "a box. okay... and this will be what size big box exactly? what are you going to construct it from?" "yeah, so we thought of this, okay? this is like the coolest, right... so we melt down the moon, right? and..." - "you do what now? using what energy do you 'melt down the moon' bro?" "sure, great question. so we calculated that if we melt down mars we can produce..." - "ugh. [brain is facepalming]" "... easily enough energy for a big furnace and fuel for that. totally doable." - "great, so you melted down a planet and melted down the moon and I don't even want to know the how at this point... can we talk about your bazillions of batteries? like, what? how? whattt?..." "yeah okay so like this is like the best bit! all we just need to do is just quickly move saturn - you know saturn, right? big planet - we just move that into low earth orbit and..." - "hey, [brain is calling it's therapist] can we pick this up another time? I just remembered... a thing... that I need to do... in a place. great chat, guy! I'll call you. sometime. for sure. gotta go"
This channel is inspiring me to stop being scared of higher math stuff and actually try to make my brain understand STEM subjects! Thanks so much for the videos
You probably know about it already but after finishing uni I went back to khan academy and have revised all the highschool/early college level maths on there and it's helped me soooo much. So many things that I just didn't get an intuitive understanding of at the time I actually understand now!
thought the same thing!!! also, if you're like me and also kind of scared by math hehe, ive seen people recommend the book "a mind for numbers" (forgot yhe author unfortunately but its by a woman who worked with microsoft i believe)
@footballmint as someone who never went to uni, trust me, that happens to us too. Simply when you grow up you have more synapses formed and you are able to comprehend things that you could not comprehend as a child.
The evidence clearly shows it's EVERYWHERE, in every Proton, Neutron, Muon/Tau and possibly Dark Taus and Dark Muons which are the neutral cores of Taus and Muons in this model that are the same as their dark anti-partners. The clue is neutron mass being near enough halfway between a Muon and Tau.. There are equal numbers of electrons and positrons in the universe at all times and everything but photons (and possibly but probably not neutrinos that probably don't exist) is made from electrons and positrons. Beta- and Beta+ radiation also show this. -- Electro-Positronic Field: -ve gas binds a ball of +ve cells freed by Full Escape Energy as electron-positron pairs -- Spin: particles pull gas in straight/pump out spirals at 90'. Motion increases gas intake, biasing spin at 90' -- Magnetism: spin flows straight to a neighbour. Gravity, energy conservation, field balance preservation cause circuits -- Mass: gas acceleration drags cells further apart inwardly but closer laterally. +ve shells, -ve gaps, packed core -- Gravity: like mass but slower acceleration with drag on field cells cancelled by dark energy so cells remain equidistant -- Dark Energy: more gas near mass shrinks field, expanded by less in voids + new matter creation / black hole growth -- Heavy Force: mass multiplier mechanism pulls in field before annihilating all heavy composite cored particles but protons -- Heavy Fusion: in the Big Bang (and stars?) 2 positrons oppositely hit 1 electron (more than 2 electrons hit 1 positron) -- Antimatter: 1,2 e_p pairs annihilate. 3: proton+anti proton or muon+anti muon. 4: neutron+anti neutron. 5: tau+anti tau -- Positronium: e_p. Muon: ep_e. Proton: pep. Neutron: pep_e. Tau: epep_e. Neutron mass is halfway between muon and tau -- Lifetime: heavy force starts when (anti) muons/taus slow from C. Electric force speed (C) and Time slow with gas density -- Beta- Decay: pep_e => pep e. Beta+: pep + new e_p => pep_e p. Weak Force: unstable atoms form and annihilate e_p pairs -- Nuclear Force: neutron electrons bond to protons. Mass and magnetism compact and strengthen the nucleus -- Black Hole: atoms cut into neutrons fused as tau cores (epep). Field spins, time slows, core annihilates, no singularity -- Dark Matter: (anti) muons/taus last longer as the galaxy thins out? Solitary (anti) muon/tau cores? 'black hole spin'? -- Photon: compressed, concentrated gas wave core pulls in field cells as it passes. Field warps diffract and interfere -- 2 Slit Experiment: photon/particle field warps diffract and interfere, guiding the core. Detectors interfere with guide -- Entanglement: correlation broken by measurement? Physical link? FTL base electric force, annihilation only in black holes -- Entropy Law: Work can add complexity that tends towards simplicity without work being done
This channel gives me the smallest, faintest, slightest hope for the future. Here we have a TH-cam vlogger who sits in front of a camera, with no (or very few) "splashy" graphics, and discusses deep topics in science and society. Many of her videos are over an hour long! She even includes equations! And yet she has 114K subscribers and thousands of comments per video. I would have thought it impossible! And it goes without saying that I'm a fan and subscriber, and truly enjoy both her topic space and her style.
One of the nice things about the LHC design is that rather than shooting a proton at a stationary target in the lab frame, it's colliding protons going in opposite directions with roughly the same speed. That means the collision, in the lab frame, is also in the COM frame so the threshold energy for pion production is almost exactly half of the pion mass per proton. No Lorentz boost required
Yes, exactly! Energy^2 = momentum^2 + mass^2 or E^2=p^2*c^2+m^2*c^4 where c is the speed of light. If p=0 then 100% of energy can go toward mass. There are two ways to think about the problem but the main takeaway is that the threshold energy is the point where as much energy as is physically possible gets turned into mass. That means the ideal scenario is two protons hitting one another, stopping moving entirely, and a pion is produced at rest (no motion) in the frame of the center of mass. In the center of mass frame you see both particles of equal mass moving toward you at the same speed in opposite directions. I think the most intuitive approach is to think about it in the lab frame of reference where you, as an observer in the lab, see one particle moving and the other stationary. Momentum still has to be conserved so when the two particles hit one another and the pion is produced at rest in the lab frame, it takes more energy to produce because the pion and/or the stationary particle will have to get kicked in the direction that the moving particle was heading to conserve momentum. So a lot of energy will go into momentum and you need more total energy to produce a particle with the same mass. The less intuitive way to think about it is from the center of mass frame since that's the frame where the pion will be produced at rest. When one particle is moving and the other is not, that frame of reference is moving relative to the lab frame. In the center of mass frame you have to adjust the math for how the two particles are moving relative to one another because, in that relative frame, the two particles aren't moving as quickly toward one another. That's the math that Dr. Collier does in the video. Because the two particles will be slower and therefore have less energy in the center of mass frame, you need to put more energy in from your lab frame perspective to get to the same threshold energy. If you, in the lab frame, perceive two particles moving toward one another with the same speed in opposite directions (net momentum of 0 as you said), then in the first scenario you can have the two protons hit one another, stop entirely, and produce a pion which isn't moving and momentum is still conserved so 100% of energy can go into mass. And in the second picture where you think about switching to the center of mass frame you get the same result: the lab frame is already equal to the center of mass frame so you don't have to adjust down their speed in that relative frame, so no extra energy is needed.
Hey - resurrecting this after a couple of months to say I’d love to understand your explanation here but it’s a bit over my head from a physics POV. I have a chemistry bachelor’s but never got to modern physics in that course of study, so my grasp on particle physics is not great. Is it possible to dumb this down even further for my benefit? 😭 Specifically: it’s hard for me to understand that a pion could be produced in one reference frame but not in another reference frame if the same physical collision is happening. I would have assumed a pion would still be created by the collision, but would be moving relative to the lab frame of reference rather than stationary (which is undesirable for experimental reasons I assume). Am I thinking about this correctly, or am I misunderstanding the physics?
@icelaenl Yeah, that can be very confusing. The point is that it's not the same physical system. Imagine you're standing at a point in space and two particles are flying toward you from opposite directions and it looks to you that they're each moving at 0.2 times the speed of light (0.2c) toward you. When you're standing in that spot with both of them moving toward you at the same speed in opposite directions, you perceive them as moving toward one another at 0.4c. What relativity says is that the way you perceive time and distance is actually affected by you standing stationary in the middle as opposed to moving. Now imagine in this same scenario somebody else were moving along with one of the particles in a way that the particle they're moving with looked stationary to them. What relativity says is that they would actually see the other particle moving toward them faster than 0.4c (I think it would be around 0.56c to them). You're looking at the same thing but perceiving two different things. Relativity also tells us that you standing in the middle of two particles of equal mass moving toward one another in opposite directions (the center of mass frame) are the one that knows the actual center of mass threshold energy. Back to the original collider experiments: If I'm standing in a lab next to a stationary target particle and there's another particle of the same mass flying toward me at 0.56c then I'm not in the right frame to properly perceive what the true center of mass energy is. The person in right frame to judge that is actually you, moving along with where the mid-point of the two particles is as the one is flying toward me and the target. And to you, moving at a speed so you stay in the midle of the two particles, you only see the two particles moving toward you from either direction at 0.2c and toward eachother at 0.4c. In the scenario of the Large Hadron Collider you can think of it as you standing between two particles of same mass flying toward you at the same speed, say 0.28c each for a total of 0.56c toward one another. Because you're already standing in the middle, you're already in the right frame to judge the center of mass speed so the treshold energy calculation would use 0.56c. However, in the scenario of say, a linear collider, I would be standing next to the stationary target seeing a particle flying toward me at 0.56c and we already know that the right measure of speed comes from you, the person moving along with the midpoint between the two particles and you see them moving at 0.4c and that's the speed measure we would use for the threshold energy calculation. So these are two different physical systems even though in both, the person standing next to the equipment sees two particles moving toward one another at 0.56c.
@@sparkalaphobia1090and a bonus, with momentum 0, one doesn't have the results flying out of the detector before one can measure them. I've always wondered though, are beam dumps instrumented or just the bare minimum to know when the beam hits the dump block?
40:53 I'm not an expert on Feynman, but I did a deep dive into a lot of his work about a year ago (so my memory may be a bit fuzzy), but I seem to recall that Feynman was perfectly willing to admit that his formalism of antimatter was *not inconsistent* with moving backward in time, and he even used that idea as a "neat trick" to skip some work in a problem, but he wasn't an advocate that it's *the* way to interpret the physics. It's just that you can't rule out the interpretation on any physical grounds (unless you say "that interpretation is nonsense because I say it's nonsense," which is more of a philosophical stance than a physical one), and in some instances it's a useful tool for getting to an otherwise difficult answer. I think we also have the benefit of hindsight, because the idea that antimatter moves backward in time has been around now for many years and we know it's not incredibly useful as a concept, whereas in Feynman's time when the idea first came onto the scene, they didn't know if it would turn out the be the next big piece of the puzzle that changes our entire paradigm. After all, the negative solutions to Dirac's equation were believed to be mathematical artifacts until he took them seriously, and before that Planck's quantization was thought to be a mathematical trick until Einstein took it seriously. Physics has a history of gaining new insights by taking the math more seriously (sometimes to our detriment, as outlined in the string theory video).
Even Copernicus's heliocentric model was used as a neat accurate mathematical trick that was not necessarily accepted as physical truth until telescopes could prove it with observations. In this case, entropy is pretty solid.
It is one way to keep QM local - let information flow forward and backwards in time (but in a way that classical information cannot be sent back). If particles are entangled, they were once locally near each other. So it can be a useful concept.
If we replace everything with antimatter then the flow of electrons would finally be in the same direction as the flow of current. (Current flows from positive to negative, electrons move from negative to positive)
Awesome idea. The budget for that will be about 10^45 dollars by the way. (Mass of the earth (10^30 grams) times the cost estimate for a gram of antimatter (10^15 dollars) from this video.)
Wouldn’t it still work the same, just backwards? If positrons flowed from positive to negative, we would have to essentially reverse the current, right?
@@jagw4832 current is just a way of visualizing the movement of energy. This has by convention been defined as moving from positive to negative (higher to lower energy) the only problem is that after we discovered electrons we realized that they are negatively charged, therefore the flow of electrons is from negative to positive. If we replaced it with anti electrons then current would still flow from positive to negative (because that's how it's defined), but the anti-electrons are positively charged, so the flow of anti-electrons would be from positive to negative, just the same as the flow of current
@@ThatUsuallyWorks Why would we not then have tp change the sign? I understand the difference between current and electron flow, but if the positrons flow from positive to negative, we would have to have our "positive" terminal where we would have had out "negative" before, no? Otherwise it shouldn't work? Or do I have a fundamental misunderstanding of current?
I honestly think the reason that a lot of people are against particle physics is that they watch a couple of Sabine Hossenfelder videos and just parrot the talking points
I think it's also partly to do with the colossal failure of projects like the SSC, which wasted billions of dollars in american taxpayer money for absolutely nothing in return. After it was cancelled not even the building was used for anything and was just left to rot for decades, it was a huge mess.
@@personzorz whether any physics was actually done there is besides the point. The SSC is just a high profile example related to particle physics which could of cemented in some people’s minds that the field is too expensive and too risky. I have nothing against the field though if that’s what you are thinking. That thing was more a failure of politics and nationalism than particle physics itself.
Or could it be that people started to just get tired of particle physicists discovering and maybe, just maybe, just started making up more and more particles and is just now trying to compete with the periodic table of elements but with very unscientific sounding names? Also, particle physics is just the most recent "In" field and you will always find contrarians regardless of whether they are watching Sabine. But really, people don't find the field now as cool because beyond the first ones discovered up to the Higgs boson the rest pretty much just complicates things without adding much practical use for both theory-building and technology applications (I mean we don't even know how Higgs boson can be applied) and it would take a couple more decades to find use for them. So yeah, if you are outside that field, it makes sense. And sure, there will always be those people and you have to understand that it has nothing really to do with Sabine, those people just watches videos like hers while they are on a confirmation bias crusade.
I think particle accelerators get a bad rep with the public because of how they get portayed. The first time they hear about them might be when they either turn on (framed as XBillion spent to look for something that might not exist) or when they get delayed (framed as sunk cost) or when they get shut down for maintenance or upgrades (impression that it was a single use billion dollar project like a rocket launch). They don't hear about the day in day out work that doesn't get big headlines. The result are so far removed from the average persons understanding or experience that its easy to feel like they didnt get any benefit themselves, or worse it stokes fears becuase it is something to do with anti-matter or black holes and other things that get used as plot devices as scary in movies. Anyone in a position to fund these things can lean into these impressions if they want to fund something else. Then contrast them (in the publics mind) to space probes or rovers or telescopes that get news stories about how their mission ended years ago but they are still going and still getting new data (framed as great value for money. Over 100% success, everything we get now is gravy). They get names and anthropomorphized. When the onboard battery starts running out (totally expected and planned for) it feels like a big tragedy but good news, they've managed to keep it going by sending an update. When its finally over we miss our space puppy and we want another one. Maybe the answer is to give new accelerators public friendly names and re-frame their work as missions that once achieved can be re-framed as bonus objectives. If you ask me about CERN my brain says ATLAS and some others I have to google.
attempt at joke follows: The reason people hate particle accelerators is because they are trying to secretly control the world by rotating microwaves backwards beside a CRT tube. EL PSY KONGROO
BobbyBroccoli has a great series on the many failures of the Superconducting Super Collider. My belief is that instead of spending the Cold War Peace Dividend on the SSC (or even smaller colliders to build the technology necessary to make an SSC-sized collider succeed) we used it to fund the Global War on Terror because nobody in congress would allow redirecting funds military bases or arms factories. Ultimately we ended up with a very fancy anti-Soviet stockpile that, eventually, reached a President with a very itchy trigger finger.
love how you said "you're wearing your overalls, you're covered in grease", because that's *exactly* what I pictured when you said "you're a quantum mechanic"... nice story telling
32:52 Technology for detectors developed to be used in LHC is directly contributing to the next generation of medical CT scanners. So there is not only the cool factor, but also a pragmatic factor for building accelerators.
@@KarlSmith1 I guess we can't all be supergeniuses like you Karl. Tell you what - why don't you start a TH-cam channel and dazzle us all with your brilliance?
Regarding your coda, brachistochrone trajectories are absolutely a thing. It's why "flip and burn" maneuvers are a thing in The Expanse. I mean, the alternatives are orbital transfers, or some fantastical FTL travel thing, right? At any rate, thanks for another video :) Love all your content, from the extremely heavy math to the extremely heavy social topics.
I've been watching your videos since the String Theory one and they're my favorite to listen to while doing work! And unrelated, but your hair always looks so nice!!
I suspect Sabine Hossenfelder has something to do with the hate on particle physics. She's openly critical of particle physics and heavily implies they just make up stuff to publish papers.
She said that any attempt to go beyond the Standard Model has been unsuccessful and expensive. The Standard Model is indeed extremely successful theory.
Ah. I stopped watching her when she started to get some fairly basic (by basic, I mean stuff I had in High School) Biology wrong (which, unlike Physics, is something I was significantly trained in). With science communicators, when they get something obviously wrong, I tend to stop watching them - since I won't be able to tell when they are wrong in an area I'm less familiar with (like Physics).
You have to take into account that Sabine is a particle physicist, though. So when she says there's (almost certainly) nothing to be gained by building a bigger particle collider she is speaking as an expert.
He's also bad at computers (digital fortress) and probably most every other realm of knowledge. But he does write stories that are constantly moving forward, which appeals to many people.
Hey, found your channel recently and just want to say thank you! Watched most of yr videos already. Love the editing style and general approach to science communication. Cheers
54:52 All large rocket engines have combustion chamber temperatures above the melting point of the combustion chambers (and nozzles). They are actively cooled (among other methods), which is straightforward if you've got a tank full of liquid hydrogen (or oxygen) to work with. You can see this on some rocket engine test footage - icicles will form on the outside of the nozzle while the engine runs, and instantly melt when they reach line-of-sight to the exhaust.
Ahh yes, the "jump really hard just before the elevator you are falling in hits the ground at the bottom floor"-method of deceleration of interstellar travel.
You've got the ADHD ick for housework and the ADHD ick for long videos, but when you put them together they annihilate resulting in a huge burst of energy
This is your best editing yet! It's great seeing how much more refined the videos have become, and so quickly since the start. Looking forward to more :)
Not even 5 minutes in and already Ive had 3 instances of 'oh wtf?!' only for ACA to immediately say "Its fine." This video needs to be named "The Antimatter Video: Its Fine...." Also, "squigs me out" aaaaand now my lexicon has a new addition! Also also, the 'single electron universe' thing was a thought experiment that even Feynman KNEW to be wrong. It was literally just a 'fun thought' he shared once that the media ran with. He did not, ever, not once, at any time, think it was a thing, and simply just thought it was cool to imagine.
As fascinating as all this is, I sometimes realize I'm not listening because I'm checking out all the cool background stuff. Really digging on that Muppet Show wall art in this video!
Yeah I keep seeing her recommended but I honestly don't get the appeal. She isn't a science popularizer. She's more of a science gadfly, around to tell everyone that science isn't interesting and should be deprioritized. Like, she's anti-nuclear power too! I just don't get the appeal. Is the average viewer of pop science an early 2000s neo-con?
I’m not sure why the “slowing down” part of the trip would have a special significance different than the “speeding up” part of the trip. If you accelerate for 10 years then decelerate for 10 years, it’s just a 20 year trip in my mind.
Another terrific video. Just a great watch. As someone with well over 400 hours in Kerbal Space Program, no, you didn't miss anything. Retrograde burns are it. In KSP people can also slow down their ships with aerobraking-using atmospheric friction on a close pass or a few low orbits to cut speed. It's a touchy process and of course it doesn't work on bodies without an atmosphere. Someone in another comment echoed the running KSP joke about lithobraking, only they spelled it "lithobreaking" which is funnier because that's what happens to the ship. KSP is just low speed intrasystem travel, nothing near the .3c speeds you talk about. KSP 2 has multiple star systems for interstellar travel, but it's early access and still missing many features.
I was watching this with headphones, and heard what I'm assuming was rain on the windows, but if anything I felt it improved the video, made me focus more on the video.
I'm halfway through your podcast and I love it. I worked in Cern (Remote) between 1981and 1985 (I'm almost retired now) If we find a way to make an interstellar drive, it will be based on the efforts and investments that are made now in this field.
I love your videos, it's like 198x, I'm about 10 years old, home sick from school and there's Mechanical Universe on channel 58 blowing my mind with physics and then Burke's Connections comes up right after putting everything into a human x technology perspective. Every. single. video. Thank you for explaining so well everything that is so amazing (and sometimes frustrating) about science!
Genuinely, so much of these physics models sounds like reading a rulebook to a mid 80's ttrpg where you could tell the DM had to make increasingly esoteric and convoluted rules because one player kept exploiting mechanics.
I mean if we’re going to allocate funds and capabilities to construct massive projects, I’d rather it go to a particle accelerator that pushes our understanding of the universe forward (LHC: 4.75 billion) over a multipurpose 70,000-seat stadium in a Los Angeles suburb (SoFi Stadium: 5.5 billion)
They're saying 100 billion dollars. 100 billion dollars for a massive particle accelerator versus 900 billion dollars used for the US military alone per year? Or less than 10 years of totaled expenses used for all the world's private jets? It's expensive, sure, but it's still small compared to the amount of crap the rich and powerful spend on, we have plenty of money for both solving world poverty and advancing the hard sciences.
Don't worry, you are right about the slowing down thing. At slow speeds, (once your orbit is circularized) you can use the upper layers of the planets atmosphere to slow you down, but at relativistic speeds, that doesn't work, you would just die. The other option, gravity assists, would sort-of work (you wouldn't die instantly), but is just as effective at speeding up ships as slowing them down, and the faster you go the less it matters (because you don't spend long near the planet). In the ultra-long term, space isn't a perfect vaccuum, and you'd have a velocity relative to the interstellar medium, so you'd eventually slow down and get dragged around by the interstellar winds, but that would take way longer than a human life. The ISM would mostly just kill you with radiation poisoning as your run into it and basically get extra-fast cosmic rays. So, yes, the only practical solution to slowing down a relativistic ship is turning your engines around.
There's also the fun little complication that if you do manage to slow down in much less time than you sped up, it probably won't be very fun for all your squishy human passengers. So unless there's some kind of crazy sci-fi momentum tech going on (e.g. Hyperion), or unless it's a probe/satellite without any passengers, it's probably not a bad idea to just do it slowly.
@@QuadfishTym That is very true. I'd expect that with most interstellar travel, you'd be going for the "ion-thruster style" efficient engines that burn very slowly for a long time, and you could accelerate much faster than that if you had the means, but there's definitely a very hard limit of how much acceleration you can do. Lithobraking on your target planet might be a very energetically efficient way to land, but it's not very comfortable for the passengers (and at relativistic speeds, uncomfortable for anyone/thing on the planet too). Similar problems ensue for other ways to "quickly" drop from relativistic speeds. Any sufficiently fast acceleration is indistinguishable from a crash.
There are ideas that you could slow down reasonably quickly with the interstellar medium by using a magnetic sail to increase the amount of particles you're interacting with.
@@massimocole9689 Ultimately, you can’t really decelerate at more than a few G’s without killing the humans inside. It doesn’t matter what machine you build, the person is a huge constraining factor.
I've had my suspicions, but after watching her casually use 10m/s^2 for the acceleration in the ball drop example, I'm convinced she is secretly an engineer pretending to be a physicist.
Have physicists considered the fact that pasta and antipasta don't mutually annihilate when combined? I have confirmed this with experiment. Might be a clue to the antimatter mystery. Well just a thought. Excellent presentation. I thought your analogy with the two solutions to the falling ball was really well done. Thank you.
Nice. Dirac was like “experimentalists. Look at the results of your experiments. If you are seeing this odd result very frequently, you should probably accept this is part of how the world works”
The way you explain relatively complicated subjects in such engaging and understandable way... How do you came up with this? Like damn. Wish my physics teachers back in the day took a page from your book.
re “Feynman thought he was really funny,” I would love it if you could do a deep dive into Feynman’s lectures, the cult of personality around him, the actual physics he did, and some of the heinous shit he said and did
Spending a decade slowing down isn't bad, though...if you accelerate for half the trip, and then decelerate for the second half, your astronauts aren't living in 0g.
Probably same time, less energy, since you'll be limited in both directions by the acceleration you want to expose your passengers to. Unless they're made of silicon.
your worry about antiprotons exploding cern reminded me of that one time i was doing outreach and a lady wanted to talk about ethics in physics with me and i was like great! i love talking about that! well, in our outreach we had said something along the lines of oh we use big colliders like the lhc to simulate and study the conditions at the beginning of the universe. and she was incredibly worried that we are playing god with those colliders. consider the ethical implications of making another big bang? arent you playing god? i dont think i managed to convince her that was never going to happen just with, you know, the energies involved in such a scenario
DOE did a release about Stranger Things www.energy.gov/articles/what-stranger-things-didnt-get-quite-so-right-about-energy-department and talked about it on their podcast.
one of the amazing flaws in human thinking is that we often can't see what we know doesn't exist... and then once we open our mind that it might exist, all of a sudden we can see what was there the whole time.
33:20 an estimation of the electricity cost of producing one anti-proton could be fun here 1:02:00 ah, it's answered here :) EDIT: a lot of the bad press about particle physics is probably coming from Sabine Hossenfelder and her public
Regarding deceleration, you can in fact use a kind of parachute to slow down at the target star. A magnetic sail, which grew out if work done Bussard ramjets, would be a vast loop pf superconductor that would deflect the oncoming stellar wind of the target star (or even the local ISM, if you had an onboard method to ionize it). Regardless, these iasues have indeed been thought about quite a lot by many people.
Hey hey, software engineer here. You did a good job describing the situation (and the stack) and you hit the issue head on. Also, a nice choice of music for this video. I'm happy to see other people (smarter than myself) also realize LLMs are not a big deal.
I wish every pop sci video on TH-cam was replaced with simple videos like this, of someone with an actual education on the topic just rambling about it. I learn so much more from this channel.
I've seen this discourse over particle accelerators on another youtube physics creator with some very problematic views on some issues and I think people are just parroting what they've seen there.
I think the problem in the movie was indeed that the trap was running on a battery which worked like a time bomb. And there were a few grams of antimatter which I think would be more problematic than a single anti-particle when annihilating, right?
@@PlatinumAltariawell, it was the illuminati who procured the stuff in the movie, so if anyone has infinite money to produce antimatter I guess it would be them by the internal logic of that world.
34:11 "People in my comments will just say these horrible things about particle physicists like they're just making stuff up when you can literally just sit down and calculate it and then go do the experiment. WHERE is this coming from?!" You don't watch other self proclaimed "science communicators" on TH-cam as you've mentioned per your most recent Q&A video, so I'll inform you and I might not be the first one: Sabine Hossenfelder. She's been spouting nonesense about particle physics and thanks to her scientifically illiterate way of making her video's where she keeps bashing particle physicists and putting them all underneath string theorists or charting them all underneath 'they're just trying to mathmetically find new particles, instead put your research elsewhere', people now in your comments are bashing particle phycisists as a whole. Thanks to her garbage video's I actually found YOUR channel! I really wanted to find more women in science to learn from besides Dr. Becky, but who DON'T spout unfounded nonesense or half-baked opinions supported by arguments from crackpot physics theories. And see here: you! Love your scientific video essays~! And am surprised to see that I even follow the equations eventhough I did not proceed with my special interest in astrophysics or physics at all, because I could not keep track of units in the formulas. I just did not have the focus or attention to keep up with my classmates in my classes for physics and chemistry education, sadly, but I do follow the basics and concept of the math very well! I would just need more time to figure out where you find the needed algebraïc formulas. :D But I understand! I can follow! I'm happy to see that I can still consume this science eventhough I now study communications. I've been actually thinking of finding work in science communication thanks to channels like these!
1:07:19 a video on "How to slow down in space" in terms of the mathematics could be very interesting - the idea of having the very fast ship yeet a pod off on some tangent and seeing what might happen in various "land on the planet without squishing" scenarios sounds cool
Okay time to be a nerd: Actually, quadrillion goes after trillion. Quintillion is the one after that. If you're familiar with numbers in a romance language then the tri- quadr- and quint- parts should be familiar as representing 3, 4 and 5. At that point, though, we'd probably start using new units of currency like 1000 TeraDollars.
I don't think you were missing anything. I'm pretty sure that if you tried to do atmospheric braking at 0.3 c, you would cause a mass extinction event on your destination planet.
I was sitting here thinking "perhaps you could deploy some kind of magnetic pod that would help in the deceleration... no, that must not work- oh, she said it"
So I'm like 9 months late asking this question, so there is a near 0% chance anyone actually sees it to answer, but @ 22:46, there are 2 protons moving, so why isn't this 2γmc^2? What am I missing?
Ohh, you are such fun 😂 and informative of course! I skipped a part of the math parts, I trust you on that, but how you explain the consequences of that math, it’s glorious! Thanks.
I am very happy to see the great work, and the science communication that is going on. Antimatter research is a great field that even takes part in the search of dark matter. For anyone how wants to see more, i can recommend the a visit to CERN where one can visit the antiproton factory see the accelerator and the experiments currently running there. PS: The longest (reported) antiproton storage is 405 days. Long storage is not the problem as long as you dont have much more than 100-200 particles.
Just noticed the copy of Introductory Electronics for Scientists and Engineers on the bookshelf. Mostly because of the spine damage which I think was a flaw in the bindings of an entire printing run because mine has the same issue in basically the same spot. Numerical Recipes is also a useful book to have.
This video will be so awkward once they find anti-time.
The boundaries that Dirac violated in his prediction of antimatter include time, gravity, and conscious observation. If antimatter exists in anti-time, then the bulk that was created during the big bang could exist before the big bang. 😮
And that's the real reason David Tenant's going to be the 14th Doctor Who. 🤓
Anti-matter is just matter moving backwards in anti-time
Any yesterday now.
.emit-itna dnif yeht ocno drawkwa os eb lliw oediv sihT
To answer the question "Does it matter?" you just need to also ask the question "Does it antimatter?" The two questions then annihilate and leave you with no problem.
I am calling the Nobel Prize committee to immediately throw out all the other names nominated so far and to close the submission for the next,..., say century?
exactly,, for example if I buy a swords. they're expensive and useless, but,, does it matter??
But in the end, does it even anti matter?
@@tsmspace "Swords"? These are super symmetrical words, right?
@@yourguard4 it's a joke about it's ok to buy swords.
"Imagine you're a quantum mechanic in the mid 1920s..."
Am I wearing overalls?
"... and you're wearing your overalls..."
Ok good. I'm picturing this.
There are a bunch of QM tools on the desk in the background
Is wearing overalls some kind of joke related to quantum mechanics that I'm unaware of?
@@Nanook128 Mechanics work on cars and wear overalls. I image a quantum mechanic would as well.
@@chrisl6546 I had to go back this video to see which books are visible, and my mind was blown to see the level and hammer.
Not gonna lie, any time someone on a video says "imagine you're..." I always go 'ok wait....[look into distance with my hand up, then slowy point at screen] ...okay got it!'
Yes, I am a blast at parties. I think....never been to one....
i once had a dream where a farmer got super famous because he figured out how to grow an anti-onion. So I think it would be pretty cool if physicists got to work on doing that
so true berry benson
Did he pass anti-gas?
that's probably the least convenient onion ever!
nice
She answered this: you just gotta accelerate an onion to .99 light speed and slam into another onion. Wham! Three onions and an anti-onion.
what bothers me the most about relativistic space travel is that shielding is never discussed. when you're going that fast, every little spec of dust in your way becomes a relativistic impactor that cannot be deflected and leaves a good-size crater in your ship
Collisions are very different at differing energy scales. A bit of dust hitting at relativistic speed won't make a crater, it will instead act like a cosmic ray (because that's exactly what a cosmic rays is). You need radiation shielding for protection. Hydrogen fuel makes great radiation shielding, and you'll have a lot that, so it's not a big deal as long as you plan for it.
You'll need quite powerful radar and lasers to take out larger bits of matter though - good thing you have an enormously powerful fuel source, or that would be a totally unworkable amount of energy.
@@SkorjOlafsen What would act like cosmic rays is relativistic gas, not dust. A 0.1 mg speck of dust at 0.3 c has 434 MJ kinetic energy, or about 100 kg of TNT, concentrated on a very small object. It would definitely leave a crater.
At typical rock density and as a sphere, the cross section of that speck is a miniscule 0.125 mm^2, and it's got so much momentum that it would have to begin being stopped for so long, and thus so far away, that there's just no hope of detecting it and aiming a laser at it (plus beam divergence is a thing). And this would be for _every_ speck of dust.
@@orthoplex64 You would get a crater that was large relative to the size of a speck of dust, but only a tiny portion of the collision energy can be dissipated that way (through creating plasma at the impact point, which then creates a crater). Once the electrons of the impactor are ionized away, creating a small crater as a side effect, the nucleons keep going until there's a direct collision with (usually) protons of the ship, which then make a particle shower depending on just how relativistic we're talking about.
So the energy of impact is mostly transferred deep in the target, not as a surface crater. Effective shielding requires a deep pool of proton-dense material, such as water or liquid hydrogen. The larger the ship, the less of a problem this is. Ice makes the best shielding, since it can't flow out through all the little holes that will accumulate, but a fuel tank that's actively being drained to run the engines works too.
Shielding a tiny probe seems impractical, but for a large ship with millions (or billions) of tons of fuel, it's just en engineering consideration among many. And unless we find some way to make grams of antimatter, millions of tons of fuel is the scale needed for a small payload.
What bothers me most is creating that goddamn much energy
I mean in sci-fi it’s solved by whatever gravity generator or shielding that exists within the universe. The only other solution ever brought up would be a SIM hull which would maybe be indestructible so therefore it’s not an issue.
"It's fine" only 5 seconds into the video, I think this is a record
I need a t-shirt.
Not the Battle Cats pfp right after I reinstalled that game.
@@slowerpickerI don't usually buy merch, but I would buy this.
@@slowerpickerthis, or "yay we did it" with a really uneasy / sarcastic smile
I can't believe you didn't even mention that all anti-particles have little tiny mustaches.
Goatees, I think. They're from the darkest timeline.
@@facingup1624 Abed?
🥸
I think we should call anti-protons "negatons" because it sounds cool and so positrons don't feel left out among the other "anti-" particles.
That, or controns.
hasbro wouldn't let us
@@TMmodify Negaton (no 'r'), not Megatron
what did you just call me?!
I like to think that a parallel universe exists alongside our being formed by antimatter and that they call them "negatrons" in it
The Expanse is the only space Sci-Fi show/book series that I know of which dealt with the need to decelerate in space travel. Everywhere they went they had to do a "flip and burn" procedure to decelerate toward their destination.
But of course, they had SUPER efficient Fusion reactor main thrusters that allowed them to continuously accelerate and decelerate (also giving them thrust gravity as a bonus). Still, closest to realistic space travel I've seen... in sci-fi that is.
There's plenty of other hard sci-fi that deal with deceleration, just not on TV.
Lost Fleet not only takes the need to decelerate seriously, it also extensively considers the problems relativity would cause for warships attempting to intercept and fight each other at relativistic speeds. Plus light lag.
Ex: In the series, targeting systems simply can’t adjust for the distorted view of the outside universe if the merging speed of the two ships exceeds 0.2c.
The series even gets down to considering physical computing limits (such as: information in a computer, no matter how powerful, cannot itself exceed light speed, so you run up against limits on how quickly certain things could possibly react, etc).
@@michaelhenry3234 I recently read "Project: Hail Mary" and am currently reading "Three Body Problem" series that account for deceleration.
en.wikipedia.org/wiki/Tau_Zero
they also manage to make significant amount of antimatter (with the alien tech lol) in the books and use it as bombs.
whenever i get stressed out i just think of acollieastro saying "it's fine"
You know what I love the most about these videos? Angela just seems so *done* with everything. Not in a bad way, more like a "look, hear me out, OK?" -- I almost want to say "Thank you for putting up with all the dumb stuff"
I think that’s just what happens while doing a phd
i want to apologise to her on behalf of antimatter
It's fine. Yeah I sense Angela is in a near constant state of exasperation. It seems to be one of her motivations to dig into something, then motivates her to communicate it.
Yeah, I like that a lot. I could imagine listening to her for hours and hours as she explains, intersperses her thoughts with research, adds social commentary, and goes off on tangents. If I were wealthy I'd pay for the privilege. Just happy she likes making free youtube videos.
...cheshire smile and double thumbs up.
Nothing is more frustrating than thinking someone is interested in a topic and then finding out that they are actually interested in a pseudoscience that's loosely based on said topic.
wait til she's 25 years post Phd...
Battery level anxiety tracker:
11%: 4:06
10%: 4:32
9%: 7:14
8%: 8:17
20%: 20:43
19%: 21:44
17%(!): 22:32
16%: 23:50
15%: 25:34
14%: 27:34
13%: 27:53
12%: 29:26
20:58 I believe this is when her tablet shut off and she went and charged it and started the problem again
I started at 15% 🤙
"Why do they annihilate?"
"Feynman"
"But, why do they annihilate?"
I already know this is gonna be a banger video LMFAO. You're so good at this type of humour
But do they? 95% of matter is 'dark' and +ve + -ve matter = neutral, more massive so also more compact matter = DARK... The magimatical fudge-packed Standard Model is a complete joke compared to this realist piss-take, or something much like it. Liberal Wasters can't understand the Conservative Universe.
--
Electro-Positronic Field: -ve gas binds a ball of +ve cells freed by Full Escape Energy as electron-positron pairs
Spin: particles pull gas in straight/pump out spirals at 90'. Motion increases gas intake, biasing spin at 90'
Magnetism: spin flows straight to a neighbour. Gravity, energy conservation, field balance preservation cause circuits
Mass: gas acceleration drags cells further apart inwardly but closer laterally. +ve shells, -ve gaps, packed core
Gravity: like mass but slower acceleration with drag on field cells cancelled by dark energy so cells remain equidistant
Dark Energy: more gas near mass shrinks field, expanded by less in voids + new matter creation / black hole growth
Heavy Force: mass multiplier mechanism pulls in field before annihilating all heavy composite cored particles but protons
Heavy Fusion: in the Big Bang (and stars?) 2 positrons oppositely hit 1 electron (more than 2 electrons hit 1 positron)
Antimatter: 1,2 e_p pairs annihilate. 3: proton+anti proton or muon+anti muon. 4: neutron+anti neutron. 5: tau+anti tau
Positronium: e_p. Muon: ep_e. Proton: pep. Neutron: pep_e. Tau: epep_e. Neutron mass is halfway between muon and tau
Lifetime: heavy force starts when (anti) muons/taus slow from C. Electric force speed (C) and Time slow with gas density
Beta- Decay: pep_e => pep e. Beta+: pep + new e_p => pep_e p. Weak Force: unstable atoms form and annihilate e_p pairs
Nuclear Force: neutron electrons bond to protons. Mass and magnetism compact and strengthen the nucleus
Black Hole: atoms cut into neutrons fused as tau cores (epep). Field spins, time slows, core annihilates, no singularity
Dark Matter: (anti) muons/taus last longer as the galaxy thins out? Solitary (anti) muon/tau cores? 'black hole spin'?
Photon: compressed, concentrated gas wave core pulls in field cells as it passes. Field warps diffract and interfere
2 Slit Experiment: photon/particle field warps diffract and interfere, guiding the core. Detectors interfere with guides
Entanglement: correlation broken by measurement? Physical link? FTL base electric force, annihilation only in black holes
Entropy Law: Work can add complexity that tends towards simplicity without work being done
The secret KSP method to slowing down is lithobraking, but that's not really an option unless you've engaged into a war across some very long distances.
if you're approaching a planet at 0.3 C you can just toggle the x10 000 timewarp and clip through the ground, leaving the other side of the planet at 0.5 C.
Have you heard the comedian skit about the astronaut who will land in Kansas, slowed by Kansas?
“From the 89s! Oh my gosh!” I already had my BS by the 80s…😊
I'm glad we've reached the logical conclusion where actual physic phds are describing elementary particles as "really small boys"
I sure hope this video explains to me how antimatter engines work :^)
It makes you go fast.
I am happy
Antimatter + matter = boom
Boom push forward.
dead
It's like an F1 racecar compared to a 1997 Toyota Tercel
Timestamps:
Intro: 0:00
How antimatter was discovered: 3:00
where is all the antimatter?: 10:50
making antimatter with science: 17:00
p + p ---> p + p + π^0: 20:42
p + p ---> p + p + p + p̅ : 26:09
antimatter factories: 34:42
why do they annihilate: 39:10
feynman: 40:54
but, why do they annihilate?: 45:49
antimatter as propulsion: 49:15
the patrons: 1:04:15
slowing down in space: 1:04:47
Wait how did you do this? Are you the kind of criminal that scrubs thru videos before watching them??
@@ethanwagner she had a table of contents at the start
I'm surprised she didn't put this in the description to have video chapters.
this should be added to the description to add automatic chapters to the video
[timestamp]: [title]
@@ethanwagner Not sure if it's the case here but some people post videos private so that a specific group (like patreon members) can view them first.
4:00 : ME: "Oh, hey! I'll pause the video and solve the equation. I come up with ..." "... 2-and-a-half seconds."
4:26 : VIDEO : "That initial velocity you threw the ball down with, 8 meters per second, --"
ME: "WHAT?! Initial velocity?! Gawds dammit!"
yes, that should be 2.5 seconds. where did that initial velocity appeared from ? Why dY = 30m and then that same dY = -30m ? Why make simple calculations complex for no reason?
I love your sense of humor, and I love that you're so dang smart, and I love that you're such a good explainer, but there's something else too...
I graduated with a major in physics from a large Midwestern university in 1974. In my four years there, there was only one female student in any physics class during that entire time (coincidentally, she was from my high school, and yes, she completed her major). It is such a joy now 50 years later to see brilliant young women like you and Dr. Becky showing other young women that yes, you can do science and you can do math. Sadly, women have been doing this for decades (centuries? See Madame Curie) but they rarely received the recognition they were due, or their work was flat out stolen.
Where will we be in another 50 years? Maybe you'll have invented a working time machine by then. :-)
It turns out you can design a lot of cool technology if you never ask "but where do the batteries go."
I'm getting flashbacks to my highschool Physics AP class where my group was assigned to explain the technology that Syndrome uses in The Incredibles. (It was a fun project.) We quickly determined that antimatter was the only way to get a high enough energy density for most of his technology to work, and that at current antimatter production rates it would take longer than the age of the universe to make enough for his flight in the film.
"okay so... all you do is just get a big box, right, and put like 83.2 thousand quintillion AAA batteries in it connected up and..."
- "a box. okay... and this will be what size big box exactly? what are you going to construct it from?"
"yeah, so we thought of this, okay? this is like the coolest, right... so we melt down the moon, right? and..."
- "you do what now? using what energy do you 'melt down the moon' bro?"
"sure, great question. so we calculated that if we melt down mars we can produce..."
- "ugh. [brain is facepalming]"
"... easily enough energy for a big furnace and fuel for that. totally doable."
- "great, so you melted down a planet and melted down the moon and I don't even want to know the how at this point... can we talk about your bazillions of batteries? like, what? how? whattt?..."
"yeah okay so like this is like the best bit! all we just need to do is just quickly move saturn - you know saturn, right? big planet - we just move that into low earth orbit and..."
- "hey, [brain is calling it's therapist] can we pick this up another time? I just remembered... a thing... that I need to do... in a place. great chat, guy! I'll call you. sometime. for sure. gotta go"
This channel is inspiring me to stop being scared of higher math stuff and actually try to make my brain understand STEM subjects! Thanks so much for the videos
You probably know about it already but after finishing uni I went back to khan academy and have revised all the highschool/early college level maths on there and it's helped me soooo much. So many things that I just didn't get an intuitive understanding of at the time I actually understand now!
Ecludian geometry fractals alchemy
Good on you! It can be done & you can do it!
thought the same thing!!! also, if you're like me and also kind of scared by math hehe, ive seen people recommend the book "a mind for numbers" (forgot yhe author unfortunately but its by a woman who worked with microsoft i believe)
@footballmint as someone who never went to uni, trust me, that happens to us too. Simply when you grow up you have more synapses formed and you are able to comprehend things that you could not comprehend as a child.
Antimatter: do we need it? what is it? where is it? how much?
Do we need it? Do we need it? Do we need it? Do we need it?
The evidence clearly shows it's EVERYWHERE, in every Proton, Neutron, Muon/Tau and possibly Dark Taus and Dark Muons which are the neutral cores of Taus and Muons in this model that are the same as their dark anti-partners. The clue is neutron mass being near enough halfway between a Muon and Tau.. There are equal numbers of electrons and positrons in the universe at all times and everything but photons (and possibly but probably not neutrinos that probably don't exist) is made from electrons and positrons. Beta- and Beta+ radiation also show this.
--
Electro-Positronic Field: -ve gas binds a ball of +ve cells freed by Full Escape Energy as electron-positron pairs
--
Spin: particles pull gas in straight/pump out spirals at 90'. Motion increases gas intake, biasing spin at 90'
--
Magnetism: spin flows straight to a neighbour. Gravity, energy conservation, field balance preservation cause circuits
--
Mass: gas acceleration drags cells further apart inwardly but closer laterally. +ve shells, -ve gaps, packed core
--
Gravity: like mass but slower acceleration with drag on field cells cancelled by dark energy so cells remain equidistant
--
Dark Energy: more gas near mass shrinks field, expanded by less in voids + new matter creation / black hole growth
--
Heavy Force: mass multiplier mechanism pulls in field before annihilating all heavy composite cored particles but protons
--
Heavy Fusion: in the Big Bang (and stars?) 2 positrons oppositely hit 1 electron (more than 2 electrons hit 1 positron)
--
Antimatter: 1,2 e_p pairs annihilate. 3: proton+anti proton or muon+anti muon. 4: neutron+anti neutron. 5: tau+anti tau
--
Positronium: e_p. Muon: ep_e. Proton: pep. Neutron: pep_e. Tau: epep_e. Neutron mass is halfway between muon and tau
--
Lifetime: heavy force starts when (anti) muons/taus slow from C. Electric force speed (C) and Time slow with gas density
--
Beta- Decay: pep_e => pep e. Beta+: pep + new e_p => pep_e p. Weak Force: unstable atoms form and annihilate e_p pairs
--
Nuclear Force: neutron electrons bond to protons. Mass and magnetism compact and strengthen the nucleus
--
Black Hole: atoms cut into neutrons fused as tau cores (epep). Field spins, time slows, core annihilates, no singularity
--
Dark Matter: (anti) muons/taus last longer as the galaxy thins out? Solitary (anti) muon/tau cores? 'black hole spin'?
--
Photon: compressed, concentrated gas wave core pulls in field cells as it passes. Field warps diffract and interfere
--
2 Slit Experiment: photon/particle field warps diffract and interfere, guiding the core. Detectors interfere with guide
--
Entanglement: correlation broken by measurement? Physical link? FTL base electric force, annihilation only in black holes
--
Entropy Law: Work can add complexity that tends towards simplicity without work being done
Please tell me if this is a reference to something. It sounds so familiar.
@@johncodyhawkins880yes. It’s reference to “The Dark Matter Rap” by David Weinberg. She used the song a lot in her video about dark matter.
@@PrivateSimy comment was a joke/reference to a previous video.
The antimatter video
The antimatter video
The antimatter video
The antimatter video.
You've capped the 'T'?!
the antimatter video
Maybe the real antimatter are the friends we annihilated and converted to pure energy along the way
This channel gives me the smallest, faintest, slightest hope for the future. Here we have a TH-cam vlogger who sits in front of a camera, with no (or very few) "splashy" graphics, and discusses deep topics in science and society. Many of her videos are over an hour long! She even includes equations! And yet she has 114K subscribers and thousands of comments per video. I would have thought it impossible! And it goes without saying that I'm a fan and subscriber, and truly enjoy both her topic space and her style.
Turns out people actually like it when you don't cater to the lowest common denominator.
That's because there's a lot of lonely nerds out there
@@kapsiWait just a minute, I resemble that remark!
@@TIO540S1yes you two are spitting images
One of the nice things about the LHC design is that rather than shooting a proton at a stationary target in the lab frame, it's colliding protons going in opposite directions with roughly the same speed. That means the collision, in the lab frame, is also in the COM frame so the threshold energy for pion production is almost exactly half of the pion mass per proton. No Lorentz boost required
Is that because the net momentum is nearly zero? One beam going in one direction and the other going in the opposite?
Yes, exactly! Energy^2 = momentum^2 + mass^2 or E^2=p^2*c^2+m^2*c^4 where c is the speed of light. If p=0 then 100% of energy can go toward mass.
There are two ways to think about the problem but the main takeaway is that the threshold energy is the point where as much energy as is physically possible gets turned into mass. That means the ideal scenario is two protons hitting one another, stopping moving entirely, and a pion is produced at rest (no motion) in the frame of the center of mass. In the center of mass frame you see both particles of equal mass moving toward you at the same speed in opposite directions. I think the most intuitive approach is to think about it in the lab frame of reference where you, as an observer in the lab, see one particle moving and the other stationary. Momentum still has to be conserved so when the two particles hit one another and the pion is produced at rest in the lab frame, it takes more energy to produce because the pion and/or the stationary particle will have to get kicked in the direction that the moving particle was heading to conserve momentum. So a lot of energy will go into momentum and you need more total energy to produce a particle with the same mass.
The less intuitive way to think about it is from the center of mass frame since that's the frame where the pion will be produced at rest. When one particle is moving and the other is not, that frame of reference is moving relative to the lab frame. In the center of mass frame you have to adjust the math for how the two particles are moving relative to one another because, in that relative frame, the two particles aren't moving as quickly toward one another. That's the math that Dr. Collier does in the video. Because the two particles will be slower and therefore have less energy in the center of mass frame, you need to put more energy in from your lab frame perspective to get to the same threshold energy.
If you, in the lab frame, perceive two particles moving toward one another with the same speed in opposite directions (net momentum of 0 as you said), then in the first scenario you can have the two protons hit one another, stop entirely, and produce a pion which isn't moving and momentum is still conserved so 100% of energy can go into mass. And in the second picture where you think about switching to the center of mass frame you get the same result: the lab frame is already equal to the center of mass frame so you don't have to adjust down their speed in that relative frame, so no extra energy is needed.
Hey - resurrecting this after a couple of months to say I’d love to understand your explanation here but it’s a bit over my head from a physics POV. I have a chemistry bachelor’s but never got to modern physics in that course of study, so my grasp on particle physics is not great. Is it possible to dumb this down even further for my benefit? 😭
Specifically: it’s hard for me to understand that a pion could be produced in one reference frame but not in another reference frame if the same physical collision is happening. I would have assumed a pion would still be created by the collision, but would be moving relative to the lab frame of reference rather than stationary (which is undesirable for experimental reasons I assume). Am I thinking about this correctly, or am I misunderstanding the physics?
@icelaenl Yeah, that can be very confusing. The point is that it's not the same physical system. Imagine you're standing at a point in space and two particles are flying toward you from opposite directions and it looks to you that they're each moving at 0.2 times the speed of light (0.2c) toward you. When you're standing in that spot with both of them moving toward you at the same speed in opposite directions, you perceive them as moving toward one another at 0.4c. What relativity says is that the way you perceive time and distance is actually affected by you standing stationary in the middle as opposed to moving. Now imagine in this same scenario somebody else were moving along with one of the particles in a way that the particle they're moving with looked stationary to them. What relativity says is that they would actually see the other particle moving toward them faster than 0.4c (I think it would be around 0.56c to them). You're looking at the same thing but perceiving two different things. Relativity also tells us that you standing in the middle of two particles of equal mass moving toward one another in opposite directions (the center of mass frame) are the one that knows the actual center of mass threshold energy.
Back to the original collider experiments: If I'm standing in a lab next to a stationary target particle and there's another particle of the same mass flying toward me at 0.56c then I'm not in the right frame to properly perceive what the true center of mass energy is. The person in right frame to judge that is actually you, moving along with where the mid-point of the two particles is as the one is flying toward me and the target. And to you, moving at a speed so you stay in the midle of the two particles, you only see the two particles moving toward you from either direction at 0.2c and toward eachother at 0.4c.
In the scenario of the Large Hadron Collider you can think of it as you standing between two particles of same mass flying toward you at the same speed, say 0.28c each for a total of 0.56c toward one another. Because you're already standing in the middle, you're already in the right frame to judge the center of mass speed so the treshold energy calculation would use 0.56c. However, in the scenario of say, a linear collider, I would be standing next to the stationary target seeing a particle flying toward me at 0.56c and we already know that the right measure of speed comes from you, the person moving along with the midpoint between the two particles and you see them moving at 0.4c and that's the speed measure we would use for the threshold energy calculation. So these are two different physical systems even though in both, the person standing next to the equipment sees two particles moving toward one another at 0.56c.
@@sparkalaphobia1090and a bonus, with momentum 0, one doesn't have the results flying out of the detector before one can measure them.
I've always wondered though, are beam dumps instrumented or just the bare minimum to know when the beam hits the dump block?
Slowing down is easy. Lithobreaking is really reliable. Especially if you don't care about your spaceship or the destination.
Angela: you just slam...
Me: into a wall!
Angela: ...down your brake
Me: oh, that works too, I guess
thank you, I've permanently added lithobreaking to my vocabulary.
Quite a tradition for the Kerbals
Isn't it lithobraking?
@@DavidSmith-vr1nb I mean i guess that depends on how well the space craft was built and the velocities involved.
40:53 I'm not an expert on Feynman, but I did a deep dive into a lot of his work about a year ago (so my memory may be a bit fuzzy), but I seem to recall that Feynman was perfectly willing to admit that his formalism of antimatter was *not inconsistent* with moving backward in time, and he even used that idea as a "neat trick" to skip some work in a problem, but he wasn't an advocate that it's *the* way to interpret the physics. It's just that you can't rule out the interpretation on any physical grounds (unless you say "that interpretation is nonsense because I say it's nonsense," which is more of a philosophical stance than a physical one), and in some instances it's a useful tool for getting to an otherwise difficult answer.
I think we also have the benefit of hindsight, because the idea that antimatter moves backward in time has been around now for many years and we know it's not incredibly useful as a concept, whereas in Feynman's time when the idea first came onto the scene, they didn't know if it would turn out the be the next big piece of the puzzle that changes our entire paradigm. After all, the negative solutions to Dirac's equation were believed to be mathematical artifacts until he took them seriously, and before that Planck's quantization was thought to be a mathematical trick until Einstein took it seriously. Physics has a history of gaining new insights by taking the math more seriously (sometimes to our detriment, as outlined in the string theory video).
If I'm not mistaken the idea corresponds with crossing symmetry in QFT and keeping it in mind when calculating scatterings can save you a lot of work.
Even Copernicus's heliocentric model was used as a neat accurate mathematical trick that was not necessarily accepted as physical truth until telescopes could prove it with observations.
In this case, entropy is pretty solid.
It is one way to keep QM local - let information flow forward and backwards in time (but in a way that classical information cannot be sent back). If particles are entangled, they were once locally near each other. So it can be a useful concept.
@@Kitchen1066I think it has not been proven that the earth is not the center of mass of the universe?
If we replace everything with antimatter then the flow of electrons would finally be in the same direction as the flow of current. (Current flows from positive to negative, electrons move from negative to positive)
Awesome idea. The budget for that will be about 10^45 dollars by the way.
(Mass of the earth (10^30 grams) times the cost estimate for a gram of antimatter (10^15 dollars) from this video.)
interesting 🤔
Wouldn’t it still work the same, just backwards? If positrons flowed from positive to negative, we would have to essentially reverse the current, right?
@@jagw4832 current is just a way of visualizing the movement of energy. This has by convention been defined as moving from positive to negative (higher to lower energy) the only problem is that after we discovered electrons we realized that they are negatively charged, therefore the flow of electrons is from negative to positive. If we replaced it with anti electrons then current would still flow from positive to negative (because that's how it's defined), but the anti-electrons are positively charged, so the flow of anti-electrons would be from positive to negative, just the same as the flow of current
@@ThatUsuallyWorks Why would we not then have tp change the sign? I understand the difference between current and electron flow, but if the positrons flow from positive to negative, we would have to have our "positive" terminal where we would have had out "negative" before, no? Otherwise it shouldn't work? Or do I have a fundamental misunderstanding of current?
I honestly think the reason that a lot of people are against particle physics is that they watch a couple of Sabine Hossenfelder videos and just parrot the talking points
I think it's also partly to do with the colossal failure of projects like the SSC, which wasted billions of dollars in american taxpayer money for absolutely nothing in return. After it was cancelled not even the building was used for anything and was just left to rot for decades, it was a huge mess.
@@MrMoon-hy6pn But it gave us a banging bobbybroccoli video so it was all worth it
@@MrMoon-hy6pnthat has nothing to do with physics because no physics was done there
@@personzorz whether any physics was actually done there is besides the point. The SSC is just a high profile example related to particle physics which could of cemented in some people’s minds that the field is too expensive and too risky. I have nothing against the field though if that’s what you are thinking. That thing was more a failure of politics and nationalism than particle physics itself.
Or could it be that people started to just get tired of particle physicists discovering and maybe, just maybe, just started making up more and more particles and is just now trying to compete with the periodic table of elements but with very unscientific sounding names? Also, particle physics is just the most recent "In" field and you will always find contrarians regardless of whether they are watching Sabine. But really, people don't find the field now as cool because beyond the first ones discovered up to the Higgs boson the rest pretty much just complicates things without adding much practical use for both theory-building and technology applications (I mean we don't even know how Higgs boson can be applied) and it would take a couple more decades to find use for them. So yeah, if you are outside that field, it makes sense. And sure, there will always be those people and you have to understand that it has nothing really to do with Sabine, those people just watches videos like hers while they are on a confirmation bias crusade.
I feel like any time anyone asks me how life is going, from now on, I should play a snippet of Dr. Angela saying "it's fine..." 😂😫😅
Pretty sure annihilating the opposing team in the physics sense is a crime.
Yeah, but what are they going to do? There's no evidence!
what are they gonna do? arrest you? you would have been annihilated along with them
I think particle accelerators get a bad rep with the public because of how they get portayed. The first time they hear about them might be when they either turn on (framed as XBillion spent to look for something that might not exist) or when they get delayed (framed as sunk cost) or when they get shut down for maintenance or upgrades (impression that it was a single use billion dollar project like a rocket launch). They don't hear about the day in day out work that doesn't get big headlines. The result are so far removed from the average persons understanding or experience that its easy to feel like they didnt get any benefit themselves, or worse it stokes fears becuase it is something to do with anti-matter or black holes and other things that get used as plot devices as scary in movies. Anyone in a position to fund these things can lean into these impressions if they want to fund something else.
Then contrast them (in the publics mind) to space probes or rovers or telescopes that get news stories about how their mission ended years ago but they are still going and still getting new data (framed as great value for money. Over 100% success, everything we get now is gravy). They get names and anthropomorphized. When the onboard battery starts running out (totally expected and planned for) it feels like a big tragedy but good news, they've managed to keep it going by sending an update. When its finally over we miss our space puppy and we want another one.
Maybe the answer is to give new accelerators public friendly names and re-frame their work as missions that once achieved can be re-framed as bonus objectives. If you ask me about CERN my brain says ATLAS and some others I have to google.
attempt at joke follows: The reason people hate particle accelerators is because they are trying to secretly control the world by rotating microwaves backwards beside a CRT tube.
EL PSY KONGROO
@@runakovacs4759 this is a really deep cut
BobbyBroccoli has a great series on the many failures of the Superconducting Super Collider. My belief is that instead of spending the Cold War Peace Dividend on the SSC (or even smaller colliders to build the technology necessary to make an SSC-sized collider succeed) we used it to fund the Global War on Terror because nobody in congress would allow redirecting funds military bases or arms factories. Ultimately we ended up with a very fancy anti-Soviet stockpile that, eventually, reached a President with a very itchy trigger finger.
So the aliens won't be silicon, but they could be anti-carbon. Seems legit.
Note to self: Stay away from aliens.
love how you said "you're wearing your overalls, you're covered in grease", because that's *exactly* what I pictured when you said "you're a quantum mechanic"... nice story telling
32:52 Technology for detectors developed to be used in LHC is directly contributing to the next generation of medical CT scanners. So there is not only the cool factor, but also a pragmatic factor for building accelerators.
This series is like The Feynman Lectures on Physics except more snarky and up-to-the-minute-y.
Dis-ing Feynman just because he’s dead!
He is every bit as snarky 😹
@@KarlSmith1Feynman doesn't know what Collier is on about either. Common Feynman L
@@KarlSmith1Hmmmm, I guess you'll enlighten us then...?
@@KarlSmith1 I guess we can't all be supergeniuses like you Karl.
Tell you what - why don't you start a TH-cam channel and dazzle us all with your brilliance?
@@KarlSmith1 I bet Feynman wouldn't object to my use of hyperbole.
Regarding your coda, brachistochrone trajectories are absolutely a thing. It's why "flip and burn" maneuvers are a thing in The Expanse. I mean, the alternatives are orbital transfers, or some fantastical FTL travel thing, right?
At any rate, thanks for another video :) Love all your content, from the extremely heavy math to the extremely heavy social topics.
I've been watching your videos since the String Theory one and they're my favorite to listen to while doing work!
And unrelated, but your hair always looks so nice!!
Appreciate your work, as always
I suspect Sabine Hossenfelder has something to do with the hate on particle physics. She's openly critical of particle physics and heavily implies they just make up stuff to publish papers.
So glad I stopped watching her recently after her... takes on things.
She said that any attempt to go beyond the Standard Model has been unsuccessful and expensive. The Standard Model is indeed extremely successful theory.
Ah. I stopped watching her when she started to get some fairly basic (by basic, I mean stuff I had in High School) Biology wrong (which, unlike Physics, is something I was significantly trained in). With science communicators, when they get something obviously wrong, I tend to stop watching them - since I won't be able to tell when they are wrong in an area I'm less familiar with (like Physics).
to be fair she's already openly critical of the idea of being right on so many things already
You have to take into account that Sabine is a particle physicist, though.
So when she says there's (almost certainly) nothing to be gained by building a bigger particle collider she is speaking as an expert.
Turns out Dan Brown was as bad at physics as he was at history.
He's also bad at computers (digital fortress) and probably most every other realm of knowledge. But he does write stories that are constantly moving forward, which appeals to many people.
A better backstory for DVC ...
M: Where were you all weekend?
J: I was dead for three days.
M: We're done. Just go.
I love these videos. She's like the Jenny Nicholson of Physics.
hilarious
I always wondered what her videos reminded me of
omg I can no longer unsee this lmaoo
Never heard of Jenny Nicholson. Looked up her channel- it is rather odd.
I didn't want to be the first to say it, but yes. Which is great.
Hey, found your channel recently and just want to say thank you! Watched most of yr videos already. Love the editing style and general approach to science communication. Cheers
54:52 All large rocket engines have combustion chamber temperatures above the melting point of the combustion chambers (and nozzles). They are actively cooled (among other methods), which is straightforward if you've got a tank full of liquid hydrogen (or oxygen) to work with. You can see this on some rocket engine test footage - icicles will form on the outside of the nozzle while the engine runs, and instantly melt when they reach line-of-sight to the exhaust.
Ahh yes, the "jump really hard just before the elevator you are falling in hits the ground at the bottom floor"-method of deceleration of interstellar travel.
your videos are very good at motivating me to get stuff done around the house. please don't stop or I think my life might fall apart
You've got the ADHD ick for housework and the ADHD ick for long videos, but when you put them together they annihilate resulting in a huge burst of energy
he begins glowing and floating and doing chores at superspeed @@gizatsby
This is your best editing yet! It's great seeing how much more refined the videos have become, and so quickly since the start. Looking forward to more :)
Not even 5 minutes in and already Ive had 3 instances of 'oh wtf?!' only for ACA to immediately say "Its fine." This video needs to be named "The Antimatter Video: Its Fine...."
Also, "squigs me out" aaaaand now my lexicon has a new addition!
Also also, the 'single electron universe' thing was a thought experiment that even Feynman KNEW to be wrong. It was literally just a 'fun thought' he shared once that the media ran with. He did not, ever, not once, at any time, think it was a thing, and simply just thought it was cool to imagine.
As fascinating as all this is, I sometimes realize I'm not listening because I'm checking out all the cool background stuff. Really digging on that Muppet Show wall art in this video!
I noticed it too ;)
We must construct additional p-ions
i'm so sad we're never ever getting another sc2 level rts
mmm pie on
mmm pear production
I'd pay for merch with "It's Fine" and a bewildered-looking Angela on the shirt/mug/fridge magnet!
Sabine has championed particle physics being a waste of money for a while now, so that's probably where it comes from. lol
Yeah I keep seeing her recommended but I honestly don't get the appeal. She isn't a science popularizer. She's more of a science gadfly, around to tell everyone that science isn't interesting and should be deprioritized. Like, she's anti-nuclear power too! I just don't get the appeal. Is the average viewer of pop science an early 2000s neo-con?
I’m not sure why the “slowing down” part of the trip would have a special significance different than the “speeding up” part of the trip. If you accelerate for 10 years then decelerate for 10 years, it’s just a 20 year trip in my mind.
I think it because you need to spend same amount of energy twice.
Another terrific video. Just a great watch.
As someone with well over 400 hours in Kerbal Space Program, no, you didn't miss anything. Retrograde burns are it. In KSP people can also slow down their ships with aerobraking-using atmospheric friction on a close pass or a few low orbits to cut speed. It's a touchy process and of course it doesn't work on bodies without an atmosphere.
Someone in another comment echoed the running KSP joke about lithobraking, only they spelled it "lithobreaking" which is funnier because that's what happens to the ship.
KSP is just low speed intrasystem travel, nothing near the .3c speeds you talk about. KSP 2 has multiple star systems for interstellar travel, but it's early access and still missing many features.
lol, I yelled lithobraking at my screen. 1300 hours across 1 and 2.
love your content! would you consider making a video on the vacuum energy problem?
10 Thumbs up !
I was watching this with headphones, and heard what I'm assuming was rain on the windows, but if anything I felt it improved the video, made me focus more on the video.
I'm halfway through your podcast and I love it. I worked in Cern (Remote) between 1981and 1985 (I'm almost retired now) If we find a way to make an interstellar drive, it will be based on the efforts and investments that are made now in this field.
I love your videos, it's like 198x, I'm about 10 years old, home sick from school and there's Mechanical Universe on channel 58 blowing my mind with physics and then Burke's Connections comes up right after putting everything into a human x technology perspective. Every. single. video. Thank you for explaining so well everything that is so amazing (and sometimes frustrating) about science!
Genuinely, so much of these physics models sounds like reading a rulebook to a mid 80's ttrpg where you could tell the DM had to make increasingly esoteric and convoluted rules because one player kept exploiting mechanics.
I mean if we’re going to allocate funds and capabilities to construct massive projects, I’d rather it go to a particle accelerator that pushes our understanding of the universe forward (LHC: 4.75 billion) over a multipurpose 70,000-seat stadium in a Los Angeles suburb (SoFi Stadium: 5.5 billion)
Shit, I'm pretty sure we could have built a few colliders just from the funds that have been stolen via high profile crypto scams so far.
They're saying 100 billion dollars. 100 billion dollars for a massive particle accelerator versus 900 billion dollars used for the US military alone per year? Or less than 10 years of totaled expenses used for all the world's private jets? It's expensive, sure, but it's still small compared to the amount of crap the rich and powerful spend on, we have plenty of money for both solving world poverty and advancing the hard sciences.
This video annihilated many of my assumptions about antimatter.💥
The most inspirational quote I've heard this year:
"And you can study that crap to learn about the world."
- Angela Collier
Basically if the universe was made of antimatter it would be better because electricity would flow the way that makes sense.
Don't worry, you are right about the slowing down thing.
At slow speeds, (once your orbit is circularized) you can use the upper layers of the planets atmosphere to slow you down, but at relativistic speeds, that doesn't work, you would just die.
The other option, gravity assists, would sort-of work (you wouldn't die instantly), but is just as effective at speeding up ships as slowing them down, and the faster you go the less it matters (because you don't spend long near the planet).
In the ultra-long term, space isn't a perfect vaccuum, and you'd have a velocity relative to the interstellar medium, so you'd eventually slow down and get dragged around by the interstellar winds, but that would take way longer than a human life. The ISM would mostly just kill you with radiation poisoning as your run into it and basically get extra-fast cosmic rays.
So, yes, the only practical solution to slowing down a relativistic ship is turning your engines around.
There's also the fun little complication that if you do manage to slow down in much less time than you sped up, it probably won't be very fun for all your squishy human passengers. So unless there's some kind of crazy sci-fi momentum tech going on (e.g. Hyperion), or unless it's a probe/satellite without any passengers, it's probably not a bad idea to just do it slowly.
@@QuadfishTym That is very true.
I'd expect that with most interstellar travel, you'd be going for the "ion-thruster style" efficient engines that burn very slowly for a long time, and you could accelerate much faster than that if you had the means, but there's definitely a very hard limit of how much acceleration you can do.
Lithobraking on your target planet might be a very energetically efficient way to land, but it's not very comfortable for the passengers (and at relativistic speeds, uncomfortable for anyone/thing on the planet too). Similar problems ensue for other ways to "quickly" drop from relativistic speeds. Any sufficiently fast acceleration is indistinguishable from a crash.
There are ideas that you could slow down reasonably quickly with the interstellar medium by using a magnetic sail to increase the amount of particles you're interacting with.
@@massimocole9689 Ultimately, you can’t really decelerate at more than a few G’s without killing the humans inside. It doesn’t matter what machine you build, the person is a huge constraining factor.
Slowing down from 0.1 C can’t take less than a couple weeks without killing the people inside. The faster you go the longer this gets.
“Snake fight” is now the first thing I associate with antimatter
Maxwell's demon at it again separating the matter and antimatter.
I've had my suspicions, but after watching her casually use 10m/s^2 for the acceleration in the ball drop example, I'm convinced she is secretly an engineer pretending to be a physicist.
She’s a physicist. The “ball” was actually a cow.
Have physicists considered the fact that pasta and antipasta don't mutually annihilate when combined? I have confirmed this with experiment. Might be a clue to the antimatter mystery. Well just a thought.
Excellent presentation. I thought your analogy with the two solutions to the falling ball was really well done.
Thank you.
Nice. Dirac was like “experimentalists. Look at the results of your experiments. If you are seeing this odd result very frequently, you should probably accept this is part of how the world works”
"Does it matter? Even if it does matter, does it matter that it matters?" - Marvin the Paranoid Android
The way you explain relatively complicated subjects in such engaging and understandable way... How do you came up with this?
Like damn. Wish my physics teachers back in the day took a page from your book.
She promises, she delivers🎉
14:17
My favorite baryogenesis conjecture: a regular-matter time traveler accidentally shipped themselves to t=0
re “Feynman thought he was really funny,” I would love it if you could do a deep dive into Feynman’s lectures, the cult of personality around him, the actual physics he did, and some of the heinous shit he said and did
I just binged all ur videos in like 2 days and this is exactly the video I wanted next lol thank you
Spending a decade slowing down isn't bad, though...if you accelerate for half the trip, and then decelerate for the second half, your astronauts aren't living in 0g.
Probably same time, less energy, since you'll be limited in both directions by the acceleration you want to expose your passengers to. Unless they're made of silicon.
your worry about antiprotons exploding cern reminded me of that one time i was doing outreach and a lady wanted to talk about ethics in physics with me and i was like great! i love talking about that! well, in our outreach we had said something along the lines of oh we use big colliders like the lhc to simulate and study the conditions at the beginning of the universe. and she was incredibly worried that we are playing god with those colliders. consider the ethical implications of making another big bang? arent you playing god? i dont think i managed to convince her that was never going to happen just with, you know, the energies involved in such a scenario
DOE did a release about Stranger Things www.energy.gov/articles/what-stranger-things-didnt-get-quite-so-right-about-energy-department and talked about it on their podcast.
one of the amazing flaws in human thinking is that we often can't see what we know doesn't exist... and then once we open our mind that it might exist, all of a sudden we can see what was there the whole time.
400 hour Kerbal Space Program veteran here, you're missing the obvious slowing solution of lithobraking.
33:20 an estimation of the electricity cost of producing one anti-proton could be fun here
1:02:00 ah, it's answered here :)
EDIT: a lot of the bad press about particle physics is probably coming from Sabine Hossenfelder and her public
Regarding deceleration, you can in fact use a kind of parachute to slow down at the target star. A magnetic sail, which grew out if work done Bussard ramjets, would be a vast loop pf superconductor that would deflect the oncoming stellar wind of the target star (or even the local ISM, if you had an onboard method to ionize it). Regardless, these iasues have indeed been thought about quite a lot by many people.
"it squigs me out" I'm going to use this *constantly* now
Hey hey, software engineer here. You did a good job describing the situation (and the stack) and you hit the issue head on. Also, a nice choice of music for this video.
I'm happy to see other people (smarter than myself) also realize LLMs are not a big deal.
I wish every pop sci video on TH-cam was replaced with simple videos like this, of someone with an actual education on the topic just rambling about it. I learn so much more from this channel.
I've seen this discourse over particle accelerators on another youtube physics creator with some very problematic views on some issues and I think people are just parroting what they've seen there.
I think the problem in the movie was indeed that the trap was running on a battery which worked like a time bomb. And there were a few grams of antimatter which I think would be more problematic than a single anti-particle when annihilating, right?
Yes, but that begs the question of how they got that much. And it definitely couldn't be contained in a small glass cylinder.
@@GlucoseBoostore, you mean.
Evidently the current record is to store 3 atoms in a laboratory's worth of equipment.
@@PlatinumAltariawell, it was the illuminati who procured the stuff in the movie, so if anyone has infinite money to produce antimatter I guess it would be them by the internal logic of that world.
I should've just gone to a trade school to be a quantum mechanic
34:11 "People in my comments will just say these horrible things about particle physicists like they're just making stuff up when you can literally just sit down and calculate it and then go do the experiment. WHERE is this coming from?!"
You don't watch other self proclaimed "science communicators" on TH-cam as you've mentioned per your most recent Q&A video, so I'll inform you and I might not be the first one: Sabine Hossenfelder. She's been spouting nonesense about particle physics and thanks to her scientifically illiterate way of making her video's where she keeps bashing particle physicists and putting them all underneath string theorists or charting them all underneath 'they're just trying to mathmetically find new particles, instead put your research elsewhere', people now in your comments are bashing particle phycisists as a whole.
Thanks to her garbage video's I actually found YOUR channel! I really wanted to find more women in science to learn from besides Dr. Becky, but who DON'T spout unfounded nonesense or half-baked opinions supported by arguments from crackpot physics theories. And see here: you! Love your scientific video essays~! And am surprised to see that I even follow the equations eventhough I did not proceed with my special interest in astrophysics or physics at all, because I could not keep track of units in the formulas. I just did not have the focus or attention to keep up with my classmates in my classes for physics and chemistry education, sadly, but I do follow the basics and concept of the math very well! I would just need more time to figure out where you find the needed algebraïc formulas. :D But I understand! I can follow! I'm happy to see that I can still consume this science eventhough I now study communications. I've been actually thinking of finding work in science communication thanks to channels like these!
1:07:19 a video on "How to slow down in space" in terms of the mathematics could be very interesting - the idea of having the very fast ship yeet a pod off on some tangent and seeing what might happen in various "land on the planet without squishing" scenarios sounds cool
Okay time to be a nerd: Actually, quadrillion goes after trillion. Quintillion is the one after that. If you're familiar with numbers in a romance language then the tri- quadr- and quint- parts should be familiar as representing 3, 4 and 5.
At that point, though, we'd probably start using new units of currency like 1000 TeraDollars.
My next space ship in Space Engineers needs to be named Paul Dirac.
Paul Di-rocket
@@Atomhaz it's mine now . XD
@@ShannonWare I hope you make it yours. Is space engineers good? It’s on steam right?
@@Atomhaz yes and yes. Those who play it but complain say either Ark is better or Star Citizen is better. But if you like Lego you will like SE.
I don't think you were missing anything. I'm pretty sure that if you tried to do atmospheric braking at 0.3 c, you would cause a mass extinction event on your destination planet.
Maybe that's the first step toward terraforming...
and how many g would the deceleration be? crew turned into liquid...
I was sitting here thinking "perhaps you could deploy some kind of magnetic pod that would help in the deceleration... no, that must not work- oh, she said it"
So I'm like 9 months late asking this question, so there is a near 0% chance anyone actually sees it to answer, but @ 22:46, there are 2 protons moving, so why isn't this 2γmc^2? What am I missing?
Ohh, you are such fun 😂
and informative of course!
I skipped a part of the math parts, I trust you on that, but how you explain the consequences of that math, it’s glorious!
Thanks.
I am very happy to see the great work, and the science communication that is going on. Antimatter research is a great field that even takes part in the search of dark matter.
For anyone how wants to see more, i can recommend the a visit to CERN where one can visit the antiproton factory see the accelerator and the experiments currently running there.
PS: The longest (reported) antiproton storage is 405 days. Long storage is not the problem as long as you dont have much more than 100-200 particles.
Haven't watched yet
just wanted to say you're my favorite youtube content creator by far
Just noticed the copy of Introductory Electronics for Scientists and Engineers on the bookshelf. Mostly because of the spine damage which I think was a flaw in the bindings of an entire printing run because mine has the same issue in basically the same spot. Numerical Recipes is also a useful book to have.
I love particle physics, it’s so damn cool. These videos make my entire day, it’s so good.