Einstein's Clocks
ฝัง
- เผยแพร่เมื่อ 7 ก.ย. 2024
- One of the most non-intuitive physics theories ever devised is Einstein’s Theory of Special Relativity, which claim such crazy-sounding things as two people disagreeing on such familiar concepts as length and time. In this video, Fermilab’s Dr. Don Lincoln shows that every single day particle physicists prove that moving clocks tick more slowly than stationary ones. He uses an easy to understand example of particles that move for far longer distances than you would expect from combining their velocity and stationary lifetime.
Walked a quarter mile for a science video? That is dedication, gave a like just for that.
Hahaha. You're right. I was amazed he did that.
Hey, even scientists have to stay in shape, so in the name of science it's understandable. ;)
He walked 30 feet and started breathing heavily
And that is why he is a physics.
Probably half a mile (walking there, walking back)
After watching this video in my bed I feel like I should go out and enjoy life more. Since going out takes slightly longer time than staying in the bed 😁
and covid says no
As a metric guy always complaining about hearing imperical units, it is awesome you guys translated the speed of light, and other measurements, to other units for people from different parts of the world to also get a grasp of the magnitude!
+Niilo Väisälä by different parts you mean murica? since everyone else uses metric, even the imperialists
+Niilo Väisälä -- *Even in* countries that use what is known as the US Customary System, which is not quite the same as the British Imperial System, Burma, Liberia, and the US, the people can't comprehend a large distance such as 186, 000 miles. And if they can't comprehend it anyway, why not use the metric equivalent, 300,000,000 meters?
@@Nehmo
Fermilab is funded by American taxpayers, who use the US Customary System, that's one of the reasons, I imagine.
Anyway, it's not like we don't have unit conversion tools at our fingertips, so this kind of complaints are rather silly, if you ask me.
@Niilo Väisälä
Everybody knows that the speed of light in a vacuum is ~300.000 Km/s... if you need Don (or any other American) to tell you that, I'm afraid that units are the least of your problems 😅
Comprehension of magnitudes =/= comprehension of units
Great video folks!
We always loved a series that was produced back in the 80's called "The Mechanical Universe." We had our kids watch it when they were grade school level because it did a great job at the time with both classical and quantum level physics. Thanks to a lot of talented physicists and production folks, they made extensive use of graphics, role-playing, etc. to explain the history and implications of the different principles and made it fun to learn.
I mention this because I love the way you've illustrated the "funkier" aspects of this theory and were kind enough to "walk" us through the math that was relevant (I'm 20+ years too rusty).
Thank you!!! :D
How do you know which clock is moving?
To the Pion, 'its' clock is ticking "normally" but space in the direction it is traveling is "compressed" to around 30 feet
... and for the photon the whole universe is squeezed to a mere sizeless dot? Because photons experience no proper time at all (nothing traveling at c does). Let's get serious: GR has been utterly demonstrated correct once and again and again and again, only dark matter might, if anything, stand in its way (but it probably does not).
Good one.
Now try to prove that relative to pions the earth clock is not slowing down. After all, the earth is moving in the opposite direction with the same constant speed.
@@LuisAldamiz any idea why atomic clock tick slower in higher gravity?
@@lukabc31 For the same reason any clock does, grandfather or quartz or whatever. I can't explain just now why that is, however.
I have noticed that events we see after the birth of a Pion that their t < vx/c² are not seen by they Pion?
And I would also like to know what is the average lifetime of Pion if they are stopped after 60ft. if such an experiment have been conducted.
I'm a physics teacher... please make videos with a lot of math for my students. They need to learn how to work out solutions of their problems.
Thanks a lot to Fermilab for doing this service, not just for America, but for the world. I've studied physics and math all my life. I only came across this obvious confirmation of relativity when I was in physics grad school.
Now everyone in the Internet can see this immediately. It's time to end the denialism online.
I'm thrilled about that way you make complex topics appear so easy to understand, I admire the work you do. Warm regards from Nicaragua
Right, but for time to be ticking slower by any significant amount, we/or the Pion would have to be traveling at near the speed of light. Traveling by a car, plane, or even by the fastest rocket we currently have, does not slow down time by a significant/measurable amount. These changes can only occur at or near the speed of light.
Rather than supporting "Einstein's clocks" an alternative interpretation of this experiment is that when the pion particle is accelerated to near light speed, its mass increases. There is a consequent increase in its inertia and in the inertia of its component parts. This increase in inertia simply slows the process and therefore the rate of decay at which the formation of muons and neutrinos can occur, as judged by the greater distance travelled before decay. Only the process itself may take longer and has nothing to do with time itself slowing down. The same effect from increased inertia with velocity would apply for atomic and mechanical clocks. Why presume that nuclear/particle transformations must always occur at a fixed rate regardless of gravity, speed or acceleration and claim it must be only time that changes?
I don't know much about Pion. But one question: How do we know if the higher speed doesn't affect the character of Pion and make it take longer to decay? i.e. the time actually remains unchanged with objects moving in higher speed?
Well, if you construct such a theory, the theory of changing in some sense particles, and you must say which one, and if your theory confirms all the other predictions of Einstein's special relativity, and if your theory can merge herself with quantum theory to create quantum field theory, well, your interpretation of reality will be truth the same. If only one of what I said doesn't happen, it's not
I have the same theory. Not sure why, but for me it makes more sense for the property of the Pion to change (maybe get fewer "decay variables" making it 'live' longer). Just saying.
How do we know that the high velocity won’t impact the time it takes for the pion to decay?
Doesn't the answer suggest that it's velocity or something to do with the change of energy and speed that simple makes the clock tick slower. In other words the faster the clock goes the slower the mechanics in the clock goes. Almost like a G forces put on the mass in anything that is moving faster?!
So next time I'm late for work I can tell my boss that in actuality I'm 5 minutes early and his perception that I'm late is due to time dilation.
QUESTION: So are you saying the Pions travel 30 Feet? Or are you saying the Pions travel one-quarter mile? Certainly they do not travel both.
THIS IS AN AWESOME VIDEO!!! You manage to explain this in a non arrogant and smooth way. Thumbs up to you! LOVE IT!
It is refreshing to hear him repeatedly say the moving clock tick more slowly. That is the way Einstein phrased it . Clocks are not so strongly coupled to time. as the are to the motion they experience.
Glad to see a quantum physicist praising Relativity so clearly, not everyone does that.
Time is everything and why Einstein was obsessed with it without time NOTHING happens. It's just one big freeze frame that never changes
You make learning this complex topic so much easier with the way you explain. Thank you!! ❤
Not complex; very simple once you look at gravity differently...
Engelhardt (Einstein's third postulate) & Crothers (Einstein's anomalous clock synchronisation)(Galilean & Einsteinian observers)(On the logical inconsistency of the Special Theory of Relativity) hav shown that using Einstein's method of synchronisation any two events that are non-simultaneous in one reference frame can be seen to be simultaneous in every different reference frame if a suitable origin is chosen. The opposite of what Einstein said.
What if there is something else happening when the Pion moves at high speed other than it moving at high speed that is affecting its life span?
Nice question! I think the answer is Occam's Razor: "The simplest explanation is preferable". I guess in this case, that would be something like: The extended pathlength was already predicted, based on relativety + no other (easier) explanation was found or observed. Occam's Razor is the basis of our scientific thinking. It's really fascination, but also has its weaknessess - en.wikipedia.org/wiki/Occam%27s_razor
Pions always move at those hyper-high speeds, just that inside a baryon (proton or neutron) they don't go very far.
@@LuisAldamiz then how do they get stationary pions?
@@jarelnomeh2345
1:44
Sorry, I'm a day late 😀🙄
@@jarelnomeh2345 pions can be „stationary“ when they pop into existence by Quantum Fluctuations (Quantum Foam).
in the pion's realm it travels 30 feet before decay but in our realm its 1/4 of a mile to decay travelling at the same velocity,and in other to grasp this we use the speed of light which is constant in small realms(the pion') and a large realm(ours)..?
The pion has more time to decay ACCORDING TO US, THE OBSERVER, therefore we see it go further. But, to the pion, time is not running slowly: it simply decays at it's normal rate. However it WILL experience space contraction in its direction of motion. Therefore, for the standard decay time it "goes further"? Do I have that right? 😵
Do you only measure the distance or can you also measure the time it takes for a pion to arrive?
I don't know... doesn't it seem more intuitive to say that pion moving through spacetime adapts to new spacetime properties every time it changes reference frame thus taking more time to decay than the one decaying in a constant environment?
Grateful for all Fermilab video, they make physic more interesting. Hmmm maybe I misunderstood the video.... It sounds like the 10 billion watts of energy / movement at speed of light, reduced the decaying rate of Pion. Similarly, when a clock is in motion (maybe at speed of light), the movement affected its inner working, causing it to report time differently. Nice.
The topic is relativity..which says speed is relative. And it also says stationary clock and moving clock. Isn't both of this statements contradictory?
I can argue that pions are not moving you are moving. You cannot distinguish.
Don, another example of the fine tune problem is the convenient existence of neutrons themselves: as you know, without them heavier elements than hydrogen could not exist because of the repulsion between protons in the atomic nucleus, so no carbon, no oxygen, no iron, no life and practically not anything except the hydrogen gas could exist. Excellent video as usual!!!
At the risk of repetition, I am posting this to this site as well as a couple of other relativity sites.
Here is a thought experiment I like to do with my Physics Students.
A group of Astronauts are going on a spaceflight to the Angry Red Planet 10 light years away. I will abbreviate that as 10c-yr. Their spaceship is very special, it can reach its cruising speed of 0.8c almost instantly after takeoff. We need to do that to simplify the calculations. I like to use that speed because it gives us 1/gamma = 0.6. You mathematicians might realize these are the sides of a 3-4-5 triangle. Note, I sometimes use v = 0.6c which gives 1/gamma = 0.8.
Your homework assignment is to do the same calculations for v = 0.6c. Due next week.
Here on Earth we calculate the time to reach the Angry Red Planet as 10c-yr/0.8c = 12.5 yrs. On board the spaceship, they measure the time as 0.6 x 12.5 yrs = 7.5 yrs. This means the astronauts will have only aged a normal, for them, 7.5 years. It DOES NOT mean they will see themselves moving in slow motion, a common misconception. They will experience time progressing normally, it will just be 7.5 years instead of 12.5 years.
Now we get to the interesting part. When we ask the astronauts at what velocity they travelled, you might think they will say 10c-yr/7.5yr = 1.33c, which is faster than the speed of light. But, remember that one of the basic tenets of relativity is that all motion is relative. When they look out from their spaceship, they see the outside world moving while they are stationary. That means they will measure the distance to the Angry Red Planet as something less than 10c-yr. They will measure the distance as 0.6 x 10c-yr = 6.0 c-yr.
So, let's ask them again. What was your velocity? 6.0 c-yr/7.5 yr = 0.8c.
Here is the cool part. On Earth we say they aged 7.5 years because of time dilation. Specifically, they travelled 10c-yr at 0.8c which took 12.5 yrs, but their clocks ran slow (0.6 x t) so they only experienced 7.5 yrs.
The astronauts say they aged 7.5 years because of length contraction. They claim they travelled a distance of 6.0 c-yr at 0.8c which took 7.5 yrs.
The only thing they will ALWAYS agree on is the velocity.
Don't forget, your homework is due one week from the day you read this.
Wayne Adams
B.S Chemistry
M.S. Physics
R&D Chemist 9 yrs.
Physics Instructor 33 yrs.
I understand time as the result of matter moving. Not that they are 2 things, but just one (matter), giving us the ilusion of ''moments passing by'' (time).
If we could make matter stop moving (hypothetically), the result will be for the observer, that time stopped, but that experiment will never occur just because the observer is made of matter in motion also.
I see time not as matter or space on itself, but the motion of it.
Maybe I'm fully wrong!
i have the same reflexion over this
Love that you mentioned Feynman at the end
This is such good shit. As a medical doctor with a biochemistry degree and an understanding of calculus based physics, I would not know anything about relativity and astrophysics, but with your videos and ones from channels like Space Time, I feel like I have a really have a good grasp of the basics of quantum physics and relativity. Thank you for all of the educational videos that you make!
That's a lot of PHYSICal demonstrations. I like how Dr Lincoln always manage to seemlessly integrate Particles experiments into his video. It demystifies and demythifies the Science behind Fermi Lab very well.
I still reckon Niels Bohr could have been one of the Star Physicists of the video -_-.
Thank you everyone for adding good humor and the hard work. Keep these videos coming.
How do you know that the higher energy and/or the higher velocity themselves are not the cause for the slower decay of the pions?
It is the cause: higher velocity slows time. The life time of a Pion is always the same
Also gravity have a similar effect: if you have two atomic clocks perfectly matched, you take one of them to orbit and the clock on land will start to click slower. After a few time you will have an important discrepancy. Satelites have to compensate for this effect (Gravity and velocity dilation)
Diego Rodríguez - if the lifetime of a pion is always the same, we would not be considering average lifetime, but a constant value.
High energy and high velocity are the same thing in this context. But high velocity in relation to what? A scientist standing next to the particle accelerator, or one in an airplane flying overhead? Maybe one on board a space station passing over? Maybe another particle in the same particle beam moving at slightly different velocity?
Relative velocity slows down passage of time in what is being observed from the perspective of "stationary" observer.
I have the same question, but I think we both mean that the energy and resultant velocity being the reason that the pion delays slower and having nothing to do with time dilation. If time was taken out of the equation as an elementary force in the universe and we just act like it doesn't exist, could we not find a suitable explanation that doesn't really on time or cause any paradoxes?
@Dr Deuteron Dr. Lincoln said the pion beam has the power of 10b electron volts, and traveling near the speed of light. If the energy and speed of the pion is only a metric that at outside observer applies to the pion, then wouldn't it seem to the pion that it was stationary and all the matter near the pion is actually being shot backwards at the speed of light? Since that is impossible, how can we say that the velocity isn't a property of the pion? I'm sorry, but I'm confused as to how the speed the pion is shot forward could not have an effect on it. If we ignore time, we could say the pion goes farther before decaying when accelerated faster. Maybe the speed of the pion gives it more density and the denser it is the longer it holds together. I just don't see how this experiment proves anything about how clocks move at speed or how time is real.
Can someone help me out here?
He diveded energy by mass which is gamma times c^2 and multiplied by time to get the relativistic time.
(g = gamma)
E/m = gc^2
gc^2*t = t'
Isnt t*g=t' ? Why do we still have c^2?
HELP: One of Einstein's thought experiments involved a person looking at the face of a clock while standing on the surface of the Earth. This person then travels away from the clock at nearly the speed of light, while observing the face of the clock during the entire trip. Assume the outbound leg of the journey covers a distance of six light-hours. Since light from the clock face travels at the speed of light and since the traveller is moving at nearly the speed of light, the traveller would observe the clock hands barely moving on the outbound leg of the journey. But what would the traveller observe on the return journey? Due to time dilation, many years would have passed on Earth when the traveller returns, so would the traveller observe the hands of the clock spinning extremely quickly on the return leg of the journey? And if this was the case, wouldn't the relative velocity of the photons from the clock face with respect to the traveller's eye on the return journey be much greater than the speed of light?
To summarize:
1. Outbound leg: Traveller leaves Earth at close to speed of light, travels a distance of 6 light-hours. Traveller observes the clock on Earth the entire time, sees almost no motion of clock hands.
2. Return leg: Traveller returns to Earth at close to speed of light while observing the same clock on Earth. Upon return to Earth, several years have passed on Earth due to time dilation.
Question: Did the traveller see the hands of the Earth clock spinning extremely rapidly on the return leg? Wouldn't that mean the photons from the Earth clock were travelling at faster than the speed of light, relative to the traveller?
There must be a straightforward explanation for this, but I'm having trouble understanding what the traveller would actually observe.
This planet travels at a speed, orbits the Sun , the Sun orbits the center of Galaxy, Galaxy moves around the Cluster, the Cluster moves along Supercluster...and we're measuring 2 clocks, into the sum of all those speeds without taking them into account that the stationary & the observer also moves? (and fast).
I have to watch this again. I don't understand the explanation, but I understand the business about slower and faster clocks.
The Michelson-Morley failed Lumeniferous Aether experiment started physicists re-thinking Newtonian physics. Various experiments and mathematical calculations (all the way back to Maxwell )contradicting Newtonian physics, culminated in Einstein's theories.
Various experiments measuring time differences with various timing devices from the 1930s through the 1970s, all confirmed results predicted by Relativity. The US government tested some opposing predictions made by some theoretical physicists, which turned out to be a failure, each test confirmed the time and clock business.
Yeah, I remember seeing some of these in the newspapers (an analog printout popular before the internet).
I have watched the video and if I understood it correctly (I am not a physics guy), the Prof is saying that moving clocks move slower than stationary clocks. So, over time there should be a significant time difference between both clocks. I have a watch sitting on my bookshelf for more than a year. I don't move it. I have a watch I wear to work and it's on my arm for at least 10 hours. When I bought the watch I wear every day, I set it at approximately the same time as the one on my bookshelf (with a difference of around 15 seconds). We are a year further and the one on my arm has not gone slower than the one on the shelf. It would differ more than a minute or minutes, but that's not the case. So, I don't understand this experiment.
You are one of the best on TH-cam
"We must see that the clock is working as normal although when we move away from the clock at the speed of light."
Elbart Einstine said if we go away from a clock( clock tower) at the speed of light, we will see the clock is freezed.
But If the speed of light is constant and non relative.
So
When we go away from a clock at the speed of light, we can't see that light coming from clock is stopped because the speed of light doesn't depend on our speed ( speed of light is not relative). So even when we go at the speed of light. We must see the light of the clock tower going at the speed of light.
So how do we observe that the clock of the tower is freezed.
I don't think it is freezed.
"We must see that the clock is working as normal although when we move away from the clock at the speed of light."
Right?
It is possible that time is determined by a kind of particle? Just like mass is determined by higg boson and energy.
If so we can control time by energy and it actually possible.
A lightyear? I'm confused.
There is a question. If the universe is expanding and the galaxies are travelling away at a speed faster than light. Then, what will happen to a clock on the galaxy that is travelling so fast? If we say time will stop if we travel at light speed, does that mean time in these galaxies have all stopped? Time is a very abstract concept. We are aware of time because we have clock or, we combine time with distance. But, if a person stands stationary on a spot and without any clock and without any concept of day and night, how can he tell the time? he will be confused what time is it.
I agree that the passage of time on the outside world APPEARS to move more slowly as you accelerate. That makes sense, but perception is not necessarily reality, and that does not mean TIME moves anymore slowly for the pion relative to the observer of the pion. Is it possible that the velocity, energy, and the mass of the pion combined actually add to the life of the particle, thus allowing it to travel further and longer? I'm just speculating, and maybe I'm wrong, but just because we observe something doesn't mean we are understanding it correctly.
The earth and space of universe are moving into the past which reduces or slows down time. When a person travels away from and faster than earth, they move farther into past and slow down / reduce time even more. The faster one travels away, the farther back into the past which reduces time.
I like the walking interlude, do more of these!
Moving, compared to what?
I would say that the moving pion's clock ticks more slowly than the stationary clock when viewed from the position of the stationary clock. The LAB reference frame. The pion's clock is not moving more slowly from the pion's reference frame. There is also length dilation going on.
how do you make a stationary pion? its speed is a product of its creation, how do you know that by trapping it you are not altering its decay rate? what is the control to verify? or are you just assuming decay is not altered?
Thanks for helping me visualize how far 30 feet is.
Since a clock on the Earth rotates about the Earth's axis, and orbits about the Sun, and spirals about the Milky Way galaxy, and streams through intersteller medium, is there a specific acton and direction a clock could bet set upon to counter these motions that would result in the clock having the slowest rate possible? If so, would the clock then considered to be at rest?
What is gamma in this example? 74? A clock aboard a pion reads t for this 1/4 mile trip and the clock of the observer reads 74t?
Can you explain what you mean by "stationary" observer as opposed to "moving"? What I mean is, that if I was the moving observer (in space say), I might consider myself stationary and the other observer moving - it's not like there is any wind to blow my hair or anything else to tell me I'm moving. And if so, it would be the other observer (the one I originally called "stationary") that is moving, so the time should go slower for that observer. Who does time go slower for? Me, The other observer, Both of us or None of us? What's the bit I'm missing?
I am hearing the word Pion for the first time. I guess i am in the wrong video :D
It's quark-antiquark pair: they are "virtually" created and annihilated all the time inside the protons and neutrons that make most of the mass of our usual "stuff", including you and me.
And right before that word he says - The basic idea is incredibly easy to understand :D
No no no, you are on right vid. You learned a new thing. Let me guess, you in fact learned many new things.
It is also a Russian artillery piece.
Is time slowing down with motion around the earth because time itself is curving around the earth? Then as time curve around the earth, the space that time is moving through also curve around the earth?
Just curious - Are all of background formulae on the blackboard part of one large idea or process?
Hi Don, at 5:55 you say 100 billion eV per pion. Where did the 100 GeV number come from? Earlier you had said the beam energy was 10 GeV. Can you, or anyone, clear this up please? Thanks.
Loved your PHYSICS ADVISORY sign
I just want to know how to find the solution to this thing.
Three digital clocks A, B, and C run at different rates and
do not have simultaneous readings of zero. Figure 1-6 shows simultaneous
readings on pairs of the clocks for four occasions. (At the
earliest occasion, for example, B reads 25.0 s and C reads 92.0 s.) If
two events are 600 s apart on clock A, how far apart are they on
(a) clock B and (b) clock C? (c) When clock A reads 400 s, what
does clock B read? (d) When clock C reads 15.0 s, what does clock
B read? (Assume negative readings for prezero times.)
So if im running the watch that im wearing might be 19:23 and the clock of someone else who is stationary will be 19:24 while we experience the same gravitational force?
How are you sure about the lifetime of a pion, can't it be that the lifetime is different and due to that you get the distance traveled to be higher than expected ?
Just wanna say, I love that you used a WRX wagon in your example 🙃
My father, Doug, taught with you and has great respect for you, and for good reason. Your videos are HILARIOUS, not to mention highly informative. What I like best about you is you take a giant blast ray to the annoying stereotype that scientists are some disconnected class of asocial creatures somehow laboring away in mysterious labs, cooking up chemicals that will hurt us or destroying planets. Well, okay. Y'all did get rid of Pluto. Still, I share many of these to show my friends that physics is not scary or boring, in fact it's absolutely mind blowing! Keep up the good work, and GREAT T-SHIRT!!!
I am a giant Slayer fan and I bought one.
if all true, then the Earth's 'clock' is moving much slower than the center of the universe. and our estimate of 13.5 billion years old (universe) could be off by 100 billion years...or more...relative to the center of the universe's 'clock'. any arguments against?
Frode Lund As a matter of fact there is a center of the universe: me.
There's no such thing as "the center of the universe".
Luis Aldamiz as someone not schooled in physics at all, I have to ask based on intuition . . . if we agree the Big Bang is a fact (still really only a theory, right?) and the Universe is continually expanding, would it not be expanding from a point of origin (i.e., the center)?
I don't understand. So Pions go at the speed of light. OK. If I input the speed of light into the Lorentz gamma formula I get infinite, which means that for us - who see the clock moving, together with the Pion - it takes infinitely longer for the Pions to decay. Essentially they will live forever as long as they go at the speed of light. For the Pions, its' like their clock is stopped so they don't age, don't decay. Right?
Interesting!
How comes that in this presentation the Pions experience a longer period of life due to their movement, while Don in the "The Twin Paradox: The real explanation"- the moving brother, does not experience the same phenomena? What is the difference between these 2 cases?
The problem with the idea of fast travel causing aging at different rates is that there is no satisfactory resolution to the Twin Paradox. This is discussed in detail in the book 'Why You Can't Catch a Rocket to Mars'.
The twin paradox is so difficult to understand, because Einstein made all the calculation assuming that there is no reference frame for motion in a vacuum. But this is not true, there is something like a space structure or a quantum field. Admittedly, we do not experience this when we are not accelerating and are not in the gravitational field, because matter is only a wave / vibration of this structure in space.
Thanks for this video. I have a question. Pions move fast, at almost the speed of light, therefore they live "longer" according to observer's perspective than they are meant to be. How do we make pions move slow? Make pions move so slow so that they immediately disappear as soon as they were created?
How does the nutrino beam line to MN bend with the curvature of the earth?
So the same object can occupy 2 different spaces? According to this video the object has enough time to travel 30' but it's time it travels a 1/4 mile where is it really? It can't be in both places
Let me ask, Does the difference in decay rate mean things near light speed experience time differently... Or just experience causality (aka motion *relative to other objects*) differently?
Considering that Light speed is the absolute limit, no particles could move relative to each other at light speed, for a particle to decay, it's constituent particles must be able to move relative to one another in order to "communicate" with other constituent particles and then one must move away from the others for the particle to decay.
At light speed everything making up the particle would remain "frozen" keeping the same distance from everything else in the particle. all parts are moving in the same direction at the maximum possible speed. making it impossible for one part of a particle to move away from the other parts.
The faster something is moving, the smaller the difference will be between its current speed and the maximum possible speed allowed. Meaning it would take more time for constituents to communicate and then move apart.
This then calls back to the philosophical question "What is time?, And what is it to experience time?"
Is time a constant? A physical concept dependent of everything else? Or is time a secondary concept, existing only as the result of other physical and independent objects existing and moving relative to each other?
Just because particles experience different decay rates why do we assume that means they experience time differently?
hopefully this makes sense to a few people.
Can you compare muon value in different niche as well as other than English language arts culture is it possible?
I'm no physics major...believe me... science in general is just a hobby of mine.
Just a quick question though....
The Pion that's charged with more energy goes further than one charged with less energy......Ok......tell me why this has to do with clocks slowing down? Seems to me it'd be a bit obvious -- that seems a bit like saying, "the cell phone with a fully charged battery remains operational longer than one with a 1% charge."
Isn't it also possible that the charge given to the Pion is affecting it's lifespan & extending it? After all, the calculated life of a Pion you provided is based on one a rest, correct?
Sorry if this all sounds like I'm an ignoramus, and for the record -- I don't dispute the phenomena of time dilation (it's also been proved with commercial jets relative to a clock on the ground, satellites have to frequently compensate for it, etc). I'm just saying that in this particular case --- that of a charged particle -- it may not necessarily be that time has "slowed down" for the particle, but rather it's charged more and thus can live longer.
hey i'm not sure if i interpreted ur question as u meant it to be but still i would like to reply. U r partially correct since d 'charge' u r talking about(in dis case kinetic energy imparted to d πion) is d exact reason why it goes far. If less energy(or 'charge' as u say) had been imparted to d πion den it would have travelled less. So we can deduce dat faster an object moves(i.e. more k. energy or more 'charge') d longer time dilation it experiences. For observer here pion travelled (1/4 mile) in 2*10^-6 secs whereas for pion it travelled 30 feet in 28*10^-9 secs.
So time dilation n length contraction occour simultaneously which keeps speed of light to be same for both of d entities.
On d oder hand d charge in a battery u r talking about is just a case of electrochemical process dat discharges it, getting reversed n chemical returning to its original state.When u charge it more , u've reversed d reaction a bit more. dere is no connection watsover.
In d 1st case observer n pion r moving relative to each other so relativistic effects come into play.
Whereas in d 2nd u n ur batteries r at rest wrt each other.
things will be different if u keep ur battery on charge while u go on journey at a speed comparable to speed of light.
p.s. I know i made a mess of it. Sorry if u get confused more cauz of dis but i'm not able to think of a better way to explain it to u .
Does lateral motion slow down time because gravity takes longer to act on or has less effect on something moving laterally?
@silverrahul many still use the term as convention
Does this mean, if I was travelling through space at near the speed of light, I would age slower? Would it be noticeable to me, or would I just experience time accordingly, essentially living the same life as here on earth in our time?
@Martin Smouter Thanks for clarifying. Physics are very weird hahaha, i love it!
The latter. You would experience time the same as living on Earth, but you would see the Universe (and everyone in it) age faster around you.
It's all relative. That's why it's called _relativity,_ haha. You always experience time travelling at the same rate your normally would; what changes is how everything around you seems to age.
can you further explain based on which formula u derived, pion beam energy divided by pion mass gives clocks difference (i.e. time dilation)
I hope the following 3 links help: uspas.fnal.gov/materials/10MIT/Review_of_Relativity.pdf#page=3 and
hyperphysics.phy-astr.gsu.edu/hbase/Relativ/relrange.html#c1 and hyperphysics.phy-astr.gsu.edu/hbase/Relativ/muon.html#c1
Summary of the explanation: "our data are inarguable".... and so are our methods, interpretations of particles behavior, interpretation o measurementes, and so on and on.
Does time have wave properties? Wouldn't that describe relativity?
Edited prior comment after finding reference that Newton did-know the speed of light is finite per Roemer's observations of the varying time-of-appearance of Jupiter's moons... furthermore Newton's color-correct reflector telescope would have shown the speed-of-light is constant among visible colors, as there was no color-aberration of fast comets...
THANK YOU PROFESSOR LINCOLN...!!!
I have a question that is difficult to formulate but I will, nevertheless, try! If I understood correctly the pion according to its own clock travels 30 feet, while according to our clock it travels a longer distance. That is because we stand still and out clock ticks faster, so the pion decay time is longer for us. Ok..if everything is correct until now then here comes the question: if the pion had the possibility to gaze at the world as it travels it would see everything around it up to 30 feet from the starting point.. but in our perspective it also experiences the things that come after the 30 feet and even up to 1/4 of a mile.. Imagine that at 40 feet there is a tree... for us the pion would hit the tree but for the pion there will never be any tree since after 30 feet it disappears.. is this what really happens or does the pion "see" or "experience" all the space up to 1/4 mile compressed in 30 feet?
Do clocks at the equator tick faster than clocks at the poles ?
Could you design an experiment where you aimed your pions in different directions and measured the decay to determine the speed and direction we are moving in the universe?
And you will get an answer that the same in all directions, because the speed of light is the same for all observers regardless of their motion, in all directions. Look up the Michaelson-Morley experiment that proved this starting in 1887 (actually attempting to start in 1881, but with some technical problems that took a few years to iron out): en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment -- they didn't have the ability to produce pions back then even if they had known about such particles, but they used light (along directions roughly parallel and perpendicular to Earth's motion) and interferometers.
@@Lucius_Chiaraviglio The speed of light is the same for all observers. That does NOT imply that the position of all observers is unchanging or immeasurable. The unchanging speed of light is exactly the reason why that experiment would work. Light speed being constant, but distance to target would change if the target is moving.
Wade Wilson If you are talking about sending pions out so that they hit something that is not moving with Earth, that would result in detecting motion relative to the solar wind first. Beyond that, it would be hard to get them to last long enough to hit anything else, and the energy required to do that would probably result in substantial interaction with solar photons. If you got far away from the Sun, then you might be able to get mostly interaction with cosmic microwave background . . . But it is easier to just measure frequency differences in that (already done with current technology).
@@Lucius_Chiaraviglio th-cam.com/video/GguAN1_JouQ/w-d-xo.html
A clock on a accelerating reference frame will tick slower. Take it up with Einstien kid!
@@Lucius_Chiaraviglio "it would be hard to get them to last long enough to hit anything else, and the energy required to do that would probably result in substantial interaction with solar photons".. Do we need more energy to make a Pion to last longer?
Love your videos been watching a lot of them lately.
Is there any evidence that stationary pions should decay the same energy as moving pions?
4:54 look at that result mirrored, multiply by 10, and round to the nearest number. It's the answer.
The top 5 superstars of Physics according to Fermilab:
- Einstein
- Newton
- Feynman
- Heisenberg
- Schrodinger
What about Maxwell ?
Yes, I would definitively have Maxwell, but Fermilab probably considers him more as a Math guy like Heaviside or Noether.
Or if you put more energy in things decay slower. It reminds me of the gyrobalanced clock for boats. It worked great heading south, then sent them toward USA on the trip north. The current affected the motion of the gyroscope depending on the way it rocks.
Your example seems to prove that if you put a bunch of energy in then they last long. That's not the same thing. Other argument for this is that the clocks in space run slower, but again a averaged degrading isotope in a completely different environment just proves that it decays at a different rate in a completely different rate.
Aside from anything else, the speed of light is taken from one part of the light spectrum. The math works in space is always the response. But it only works in space when you cheat. You add red shift, something usually used to show speed difference in other waves, but light is part wave part partical. So we call it wavelength and assume time changed. And we add the expansion of the universe according to it's distance from us, not source, or where we are heading. So as long as we fix the math it always works.
How could our individual reference change everything around us in the same system? Einsteins version of neetons ball feather experiment suggests they didn't move. That's why they hit the ground at the same speed. I argue we all see them drop in relation to earth. If they don't move then why not shoot straight up not down depending on the iss viewing the experiment. I have yet to meet a believer who will stand under the cannonball.
Let's test it on planetary scale as a cannonball and feather are very similar mass compared to the moon. So let's place a feather in space on the opposite side of the earth to the moon at the moon's orbit, and see if the feather stays in that orbit. Einstein says yes. I bet it won't as gravity will affect such different masses differently.
Does that mean that a light beam experiences { assuming is able to experience something} no time? Or a star-ship that reaches c arrives instantly ?
From the perspective of the light beam, yes. It would "experience" no time passing. Similarly, a star-ship that reaches c would not experience the time "in between" its departure and arrival.
Is there an explanation as to why this occurs?
Is there any point at which an inertial frame of reference becomes so big that the laws of relativity no longer apply? For example, many distant galaxies are moving away from us at several times the speed of light, which should not be possible. What is the explanation for this? Does that situation represent a non-inertial frame of reference because of acceleration?
This does not necessarily prove Einstein's theory of time dilation. It is possible that high velocity just happens to affect subatomic particles and subatomic forces in ways we still do not understand. Newton was a genius but he didn't get everything right. The same could be said about Einstein.
Einstein gets zero out of 1000. Everything about STR & GTR are wrong. The worst thing about Einstein is the twins contradiction.
So if I get the argument correctly, time is moving faster relatively for us and so we see that the pion has travelled 1900 odd ft before it decays , makes sense, but.... From the point of view of pion it still decays at 28 ms as far as its clock is concerned and it has travelled 1900 ft in that time? Doesn't that break the cardinal rule of speed limit as far as the pions frame of reference is concerned?
thanks that makes sense, but if the pion comes to a sudden stop it will then see that it has indeed travelled 1900 ft, but I suppose the sudden deceleration means it's time accelerates and so that the speed is maintained.....
+ScienceNinjaDude I meant if the pion is brought to sudden stop after it travels 1900 ft (wrt frame of reference of the observer) once it comes to a stop it also sees that it is now 1900 ft from the observer and not 30, so it would assume then that it travelled so much distance in what it felt was a short time, but I suppoe the deceleration would cause time to go fast again for the pion frame of reference such that it will balance out to maintain 'c" speed limit.
Hi All - could distance be what has been shortened instead of time? Because if we reference the Pion to itself, then his lifespan will be the same, meaning he will only move 10 meters and not the 1/4 mile, right? Does this mean space and time are intrinsically connected, and they are dependent variables from each other? If yes, then if we move at the speed of light, then time stops, and space ultimately shrinks to null, making it possible to go from one side of the universe to the opposite side in an instant? But then light itself will not exist since time will be stopped in the light time frame (since the light goes on light speed) and space will be infinitive small. Conclusion: I know zero LOL
Just a thought. Suppose there were an ultimate end to the universe and that the Universe is expanding. ( i.e. the ultimate end becomes something new). Perhaps we would never reach it because as our velocity increases, our clock slows down. So perhaps the velocity needed to reach the end of the Universe would never be enough to overcome the slowing down of our clocks as we move faster and the rate of the expansion of the Universe, hence we could never reach the end.
+Marc Lisevich This is actually similar to the 'big rip'. Assuming the universe is expanding at an accelerating rate, eventually, every atom in the universe will be receding from every other atom at velocities greater than c, due to the expansion of space in between. Although the universe won't 'cease to exist', for all intents and purposes and especially from our perspective, it will have ended. At this point I don't think it matters much that clocks tick differently across the universe. Perhaps there is more to it though. For instance, if we were to imagine ourselves riding a pion travelling at near the speed of light, how would we experience space? Clearly our metre is no more relevant than our clock? Perhaps our atoms will get dispersed at infinitely great distances, but since our clocks have slowed down due to relativity, we wouldn't perceive it as such. That's pretty weird, it must be wrong.
Just another thought. Suppose we do not have clocks at some level. If the clock isn't slowing for these particles, then we would have imaginary energy. So it might be possible to move faster than the speed of light, no one would know, and then reappear somewhere if we can get our energy to be real again. In fact this might be another dimension where raising energy^4 gives us real energy again. Perhaps we are surrounded by imaginary energy all the time, but because it doesn't follow EInstein's laws, we cannot observe the energy.
Is there a purely particle based explanation for extended lifespan? Even if not very popular or accepted.
Just an example of what I am looking for:
Pions moving with close-to-c have significantly more energy than stationary ones. Thus upon decay, more energy is released. This in turn cause higher probability of interactions of particles which were formed as a result of other pions’ decay and form new pions. And this delay-recreate loop continues several times until enough energy has been dissipated, probability of immediate pion forming going down, and as a result pion group began decaying at a rate of stationary pion group decay but much later.
In other words, internal “clocks” are ticking at the same rate, but observed decay at a later time is merely decay of N-th generation of pions, not the ones that were generated at the target.
Or, perhaps, even simpler, probability of decay is not constant and depends not only on time but on total energy as well. The more energy, the longer it takes pions to “shed” it and decay.
@silverrahul sounds too categorical. There are even alternative theories about relativity. Not accepted but not outright rejected.
I would expect even delay in decay have alternative theories. Or at least experiments trying to establish something different.
Unfortunately looking through the log, does not see anybody from Fermilab follows up on viewers’ comments or questions:(
@silverrahul I specifically said would like to hear about non-accepted theories as well.
“Also it would be surprising indeed if fermilab responded to comments on a 7 year old video”
Well, you found my question pretty promptly. No reason for Fermilab stuff to not see it as well. A few sentences, perhaps a link or two for additional research, would go a long way to make subscribers happy and wanting to watch more…