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- เผยแพร่เมื่อ 9 ส.ค. 2023
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Atomic clocks are the best timekeepers humanity's got these days, but scientists are working toward something even better: a SUB-atomic (aka nuclear) clock.
Hosted by: Hank Green (he/him)
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Sources:
www.eurekalert.org/news-relea...
home.cern/news/news/physics/i...
www.ans.org/news/article-5047...
• ISOLDE takes tick forw...
www.nature.com/articles/s4158...
www.nature.com/articles/d4158...
cerncourier.com/a/from-atomic...
cen.acs.org/articles/92/i48/A...
physicsworld.com/a/optical-cl...
www.nist.gov/pml/time-and-fre...
www.nist.gov/pml/time-and-fre...
www.nist.gov/system/files/doc...
www.pnas.org/doi/10.1073/pnas...
cosmosmagazine.com/technology...
oceanservice.noaa.gov/podcast...
news.mit.edu/2020/atomic-cloc...
news.uchicago.edu/story/resea...
iopscience.iop.org/article/10...
jila.colorado.edu/sites/defau...
www.nature.com/articles/natur...
journals.aps.org/prl/abstract...
journals.aps.org/prl/abstract...
www.nature.com/articles/s4155...
thoriumclock.eu/wp-content/up...
www.nature.com/articles/s4225...
Image Sources:
tinyurl.com/55m7j6ac
commons.wikimedia.org/wiki/Fi...
www.gettyimages.com/detail/vi...
commons.wikimedia.org/wiki/Fi...
www.gettyimages.com/detail/vi...
webbtelescope.org/contents/ar...
• Tour of the EMS 01 - I...
www.gettyimages.com/detail/vi...
commons.wikimedia.org/wiki/Fi...
commons.wikimedia.org/wiki/Fi...
www.gettyimages.com/detail/vi...
www.gettyimages.com/detail/ph...
www.gettyimages.com/detail/vi...
www.gettyimages.com/detail/il...
webbtelescope.org/contents/ar...
science.nasa.gov/ems/01_intro
www.nasa.gov/directorates/heo...
www.gettyimages.com/detail/vi...
www.gettyimages.com/detail/vi...
oceanservice.noaa.gov/facts/t...
www.nasa.gov/mission_pages/ch...
commons.wikimedia.org/wiki/Fi...
www.gettyimages.com/detail/vi...
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I was about to switch to linode...
Cesium: Am I not enough anymore? 😢
Cesium makes for a great element sample for an element collection! That said, it can be quite expensive to buy. Best off making it yourself, which is one hell of an experiment, one you can be proud of! It's such an awesome golden color.
No.. its just... its not you cesium. Its me... Im sure you'll find another physics process....
Sorry but I need something thats got a better wobble when it's feet hit the beat. Baby. Old days I'd climb up the ladder all shifty like in the middle of the night but youre just not that tightly bound down there anymore especially that gap. Well I'd tell you to hit the bricks but I'd rather walk the Planck. 😎😘
Sorry, babe, we’ve just grown apart.
@pdxmusl1510 it's because of thorium isn't it
Thank you for this well researched documentation. I myself graduated and earned a PhD on optical clocks and I always was fascinated by the next-gen nuclear clock proposals. In fact, only Thorium-299 allows for these muclear clocks. You did a great job of compressing the vast information available in this field down to below 8 minutes, without oversimplifying. Thank you
I like your name. Takes me back to 2002.
@systemofapwne Why not use the frequency of the laser(used for exciting Cs133) to measure the passage of time accurately? Is it not consistent enough?
How is it diff from the atomic clock? Where the frequency of light emitted is measured?
(Noob here)
Hey, I just want to say on behalf of everyone here. Thank you for continuing to feature yourself in these videos. Hope things get better.
Can I get a hip- hip hooray for Hank!! We all luv ya Hank!!
You absolutely ROCK!!! 👏👏👏👏👏👏👏👏👍
Is it just me, or have we been through this before?
Hope you're well, Hank.
Good to see you hosting Hank, you're a great presenter 👍
Its always thorium that does the cool stuff, from reactors to the tracking of time. #THORIUMGANG.
Except for nuclear power compared to regenerative options is inflexible, expensive, even when you solve the nuclear waste problem.
Replies like this are why we need SciShow to discuss why it doesn't have to be that way. Specifically I'd like to see content discussing generation 4 and small modular reactors, but honestly more nuclear stuff in general. Pretty please?
@@jlp1528 While true, there are still some major hurdles, but I think they are honestly basically self-imposed via extensive and rigorous regulations. The real problem, tho, is that you can only remove so much of that. That's where the SMR's come in. I honestly think the LFTRs or some variant will be the eventual winner. Maybe a modular LFTR, or some such like that.
@@kindlin we're getting close on LFTR. They approved the molten *chloride* experiment, I imagine fluoride would be similar
@@kindlin The reason why there are "extensive and rigorous regulations" is that the materials involved, even if we're talking about thorium breeder reactors or other new(er) proposals on GEN IV reactors, are dangerous and pose a potential proliferation risk.
You might think that, what's the fuss, they're passively safe and so on and a bunch of other claims not yet substanciated by actual prototypes (because nuclear engineers have not yet worked out the kinks on liquid salt fuel or pebble bed gas cooled reactors, and there's no guarantee they actually will).
Given all of that, just pretending all of those problems are solved, It might not be a good idea of having a whole bunch of small, container-sized reactors sitting around. Because they might not melt down, but they are still potentially hazardous, and you need to secure each and every one of those SMRs to the same level as a spent fuel facility for the clunky GEN IIs and III we have today.
The Soviet Union, in its day, built hundreds of terrestrial radiothermic generators and put them in remote places to power radio beacons and light houses. They remain in the wild to this day, some in hazardously bad condition, because the Russian government did not and does not have the political will or money to clean them all up. They are potential death traps for the curious, greedy, or ignorant. Is Terrapower going to exist long enough as a legal entity to clean up each and every SMR they build? Or will taxpayers and superfunds have to foot the bill for that one day, after a SMR leaks into an aquifer, or a would-be metal thief eats 20 Sieverts of bremsstrahlung?
Don't get me wrong, I'm not anti-nuclear because "nuclear bad" or something unreflected like that. But, as the tech industry continues to demonstrate, throwing around buzzwords doesn't change hard economic, ecological, scientific or social facts and contexts. I don't think it's a good idea to funnel a bunch of government money into "nuclear startups" that could be going into renewables, sustainable social housing, or the many underfunded social programs because of the shiny promise of GEN IVs. It's TESLA all over again in my eyes, delivering a product that's not going to keep the promises it sets, while diverting funds into the pockets of VCs and billionaire stock holders. But that's just my IMHO.
Yay! Finally getting time keeping down to a size where we could have our own personal clocks and, maybe one day, small enough to carry around.
Hank, I'm a cancer survivor and I applaud the fighting spirit you've shown thru your battle. You're going to win this BANK ON IT!!
I know you'll never see my comment, but I'm looking forward to make more years of videos - KEEP PUSHING
So they're essentially ringing atoms with lazers, and using the note to measure time.
That is such a cool metaphor!
SciShow saw It’s Okay To Be Smart post about electrons and energy ladders and decided to out-nerd them by going nuclear.
Seeing Hank on here always cheers me up
He has mohawk
My neutrino clock is brilliant. Really hard to read though.
lol. Real accurate, but a pain to get the results =)
Quantum Physics Fun-Fact: One of the things that can throw off the orbital energies of electrons is virtual particles popping in and out of existence within the atom's structure--also known as vacuum energy fluctuations. So, if a virtual positron were to pop up near the nucleus, it would then "pull" on the electrons in the orbits ever so slightly, and so on.
This effect is most noticeable in the hydrogen atom due to its minimum number of electrons and protons, and is known as the "Lamb Shift."
Edit: Typo correction
If the laws of physics did drift over time, how would you notice it in a nuclear clock without something even more accurate to measure it?
You compare clocks of different type. What generally is compared here is the finestructure constant: the scale for electromagnetic coupling. Different elements have different cupping strengths to it, depeneding of their constitutions. So if you compare these clocks with sufficient accuracy over time, you might see (or not see, as so far) how much physical constants might have drifted
@@systemofapwneis this like say different clocks from different places assuming laws change in different places? Sorta like time dilation?
Or is this like change on a universal scale? If in that case how would one compare two clocks wouldn’t the change occur for both?
@@zefellowbud5970he means universal law changes. You're correct that both types of clocks would change, due to different composition they would change by different amounts which can be measured.
I'm commenting because Hank asked me to.
Thank you all, I love you all, your better educators than the majority of teachers that I had when I was in school.
They said I had a learning disability, but it's clear that the disability wasn't on me, because they were unable to communicate with me properly. I can play over 4 instruments and a I'm actively progressing in 2 languages.
And I keep learning amazing things about the natural world from trustworthy educators here on TH-cam. Where was that written on the award they handed me that read: "most likely to fall asleep at the end of the world?" they were just offended that they were too boring to maintain a connection with my attention. Honestly I think they were bad teachers, because they didn't consider that their teaching methods won't work on everyone. And when I teacher sends a kid to the principals office for falling asleep in class, maybe before they do that they should re-evaluate how they are communicating, or if they had some sort of student feedback to help be a better teacher. O one is perfect at anything there's always room for improvement.
hope you are okay hank im behind on things but i think i understand. always great to listen to you ^_^
Hi Hank!
You're cooler than thorium! (And thorium is pretty cool.)
Hope you are doing beter Hank. Thank you for the awesome content
Atleast the clock is not timed to a nuke, that qould be unironically chaotic
Just got a breakthrough in this today. Thorium transition was recorded.
what kind of interaction does UV-sized energy gap correspond to in thorium nuclei? like mentioned in the video, nuclear transitions are in the gamma scale, but the nucleus can do other things aside from its nucleons dropping from the energy ladder
NMR uses nuclear *spin* transitions, and its characteristic frequency is in the radio range
0:08 i prefer to measure the passage of time in daylights, in sunsets, in midnights and cups of coffee
I know I play too many RTSs because when he said "gamma ray laser" my first thought was, "that would be a really nasty weapon in a battle."
Hey Hank, DFTBA ❤
20 years ago I stood on one side of a room and counted off with someone on the far side of the room to sync the Caesium clocks for the satcom links from one coast to the other. basically giving the ticks the same labels on different systems. fun times
Thanks
I demand a science video with the octopus hat! It’s glorious and needs to make an appearance before you grow back your hair
Maybe one about cephlopods (sp?)?
thanks sceanse
What I love about these new generations of clocks (orders of magnitude more accurate than caesium clocks) is how much of a role general relativity plays in the synchronisation of clocks across geographies. The clocks must sit in EXACTLY the same gravitational potential in two different locations in order for them to run at the same frequency. Literally centimetres of equivalent elevation difference above sea level will be enough to knock them out of sync by a meaningful amount.
I think this links to what hank mentioned about measuring plate tectonics, where shifts in magma and crust would cause the clock to experience a different gravitational potential and you could measure this by comparing the speed of time on one clock relative to another. Amazing concept and could be worth a video itself.
Given the voltage variations in our grid caused by inconsistent input from wind and solar, theyre removing the current regulations that limit current frequency. The most obvious fallout is that any clocks that run on mains AC are now quite inaccurate. The clocks on my oven and microwave now run fast by about 5minutes each week. Very annoying
Cool
What clock would we use for reference to detect the “drift” mentioned at the end?
So an atomic clock is like playing shoots and ladders.
Chutes and ladders?
That's actually a common misconception. It's more like Parcheesi.
Must be American. You either climb the ladders or get shot.
@@kantpredict You need to shoot the atom with a laser of the correct frequency.
Hopefully thorium works 🤞🏽
can't wait to see that watch on my wrist.
Those high powered gamma lasers could be used to do spectrum analysis of distant galaxies...
Thanks Hank, hope you are doing ok.
He is cancerous
Hank, you are sincerely looking wonderful!!! ❤❤
Thorium-299: I AM WORTHY!
"Ye canna change the laws of physics, laws of physics, laws of physics,
Ye canna change the laws of physics, Captain"
interessantíssimo!!!
thanks you sponsorblock!
Kamla Harris is the best way to measure the "passage of time" 0:08
If these clocks are nuclear powered, then could we say that those old digital ones were quartz powered?
Or perhaps this ones are considered nuclear powered because they need a nuclear reactor to power the ultraviolet laser for any meaningful amount of time?
Hold your horses. "Real" absolute clocks (=time standards) rely on the fact, that energy levels of atoms (electronical structure) and here, nuclei energy states, are universal and (to our recent knowledge) constant.. there are hypothesis beyond the standard model proposing otherwise, yet, the best clocks couldn't find deviations beyond 1 in 10^18+ (18+ digits after the comma!). Nuclear clocks, once they become a reality, will improve the field. Right now, they are far beyond viable.
Quartz clocks aren't powered by the quartz crystal, they're regulated by it.
You still have to put a battery in and that's your power source. The quartz is what is known as piezoelectric, it oscilates when electricity is sent to it.
Basically the battery charges the crystal which immediately begins vibrating, the watch circuit measures the vibrations and uses that to count time.
It's not super accurate though, the timing can drift depending on the battery charge but it's good enough for everyday, regular people's needs.
You don't really need a clock that measures time through the nature of the fabric of reality to tell you when Starbucks is opening.
Gracias. ¿De qué precisión estaremos hablando?🤔
One note about this is it will require a new definition of the second, because the Thorium nuclear clock is several orders of magnitude more precise than the current standard.
Defining it on the Rydberg frequency seems like the logical move to me, if we get a clock of comparable accuracy.
I am more convinced, that next SI-Second definition will be rather on optical transitions like Sr or Yb neutral atoms Yb*, Al*, etc Ions in the optical domain. Since the invention of the frequency comb about 20 years ago, the whole field of optical clocks developed so rapidly and has reached performance beyond the Cs clock, dating back to 1967. For Thorium nuclear clocks to catch up, there is still a long road to catch up. Especially finding the clock transition. I have myself worked in the field of optical clocks for an element (Mg), where the clock transition before wasn't known (just indirectly). It took us many years to find the transition and even more to not even get close to the performance of Sr or Yb clocks. For Thorium 299, the transition is fully unknown. It's like trying to find a needle in the haystack where the haystack is as big as our galaxy. Even when there is a lucky shot soon, finding the transition, it will take them many many years, if not decades, to catch up to the state of the art clocks. Especially since the "oscillator" (atom or here nucleus) generall is not limiting but rather the laser source, exciting the transition (hint: ultra stable laser resonators)
@@systemofapwne Hey I am doing my Undergraduate course now and I have been fascinated with clock and clock mechanism all throughout the spectrum of mechanical to atomic , the atomic one was part due to interest in GPS tech , I wish to pursue higher studies in this domain in "Temporal Quantum Metrology" , if you do not mind can I connect with you via any social or discord ? THANKS!
Or maybe to get nucleus excited, have it listen to that one Pointer Sisters' song on repeat instead.
Oh boy, promise of a new existential crisis!
Fascinating video. PLEASE go into the part about constants potentially not being constants more! It would be a perfect segue into the "tired light" hypothesis, and it's always nice to hear about such things from a source you know you can trust instead of some dude spewing sensational junk on the internet... 😉
I'm pretty sure "Eureka" had an episode on this... and it didn't end well for Stark!
Excellent video! "Um, actually..." moment so forgive me: Actinium decay into Thorium @ 4:57 should be a Gamma decay (a photon) & a neutron-to-proton transition, emitting a photon not a Beta decay emitting a neutron (as depicted). Otherwise it would still be Actinium 👍
Good point.
I like how our mental models of reality can be misleading to the actual functions of reality.
Navigation systems would be greatly improved. Other than that I can't think of any other applications. Perhaps monitoring gravitational waves since they warp time as well as space.
They named another use in the video: measuring the constancy of "constants" - which, if any of them showed any drift, would be HUGE.
It can also help speed up servers and other internet devices. On big servers there is an artificial delay to ensure that all the packets are received with the correct time stamps, but having super accurate time stamps would relieve the need for the delay
Thank you for saying that universal constants may not be constant. It's been driving me nuts that so much 'known' about the universe is based on these constants, such as the age of the universe, the size, the expansion... Personally I have a theory that the gravitational constant measurement keeps coming out wrong because it keeps changing... and also it's probably a constant and a variable in a trenchcoat.
Unless you can show that the constants... they the are constants. So far no one has any data of them changing. And precision currently is quite high for measuring these things.
Thorium is the key to the future I guess
mama tachibana understood it all.
she's now buildin' one.
she would also like to live at cern, she's a stan.
💜🤓🤭🤯😝🤣💙
i was gonna say, we have atomic clocks, but they mean Nuclear...
How long till some mad lad attempts a Quark clock?
I thought clock go BOOM
Hank, how do we know the laws of physics are constant over time?
I love unpersonalized ads
Wouldn't the fact that nuclear clocks need such high-energy electromagnetic waves (x-rays or gamma rays) to work also make them extremely dangerous?
Thats why scientists increased the speed of light in 2208!
G.N.E. !!
❤❤
How do you measure the accuracy of a clock?
The cesium clock is the _literal definition_ of the second, so once you measure exactly 9,192,631,770 oscillations of that atom's lowest excited state (see: this video), you'll know you just found the second. I assume the statement that it takes X billions of years to lose a second is based on calculations, rather than an experiment, as the experiment would just be measuring the definition for the sake of measuring it. Once we get these mythical nuclear clocks, we can then actually TEST whether our calculations of the cesium clocks are accurate, and we might find it was more or less accurate than our calculations initially showed, leading us down some rabbit whole to eventually figuring out quantum gravity or dark matter or something.
Canada has had an atomic clock for decades
I can't wait until we have nuclear everything in the future wowww!
From pendulums to quartz crystals to caesium and now thorium, dang
Scientists trying the REALLY complicated time piece designs lol
Glad to see you kicked Cancer's ass
👍
Hank, if I buy you a bowler hat, will you wear it in a video?
Okay, but how do they count the ticks at such high frequencies?
In the optical domain, such as visible light, generally with a frequency comb. That's the whole catch for Thorium 299: it's not MeV (gamma rays) but several eV (visible/uv light).
Huh... neat
I like the idea of a more accurate time piece, but will I grow a 3rd eye while wearing it?
If Terry Pratchett has taught me anything, this will end badly.
A Gamma ray laser? Where can I get mine?
Get Senku to count seconds
So how are you doing mr Hank 👉👈
⭐🙂👍
How /would/ they know if the clock is off though???
If it doesn't match another similar clock?
but what if that clock is the off-sync one???
@@awaredeshmukh3202
If we already have a clock that is accurate to one second of the age of the universe then why don't we just divide one second by the age of the universe and add the result to every second of the clock to get 'perfect' accuracy? Just a thought, but i'm only 56 (+ 1 divided by the age of universe) seconds into the video.
Mississippi is tooooo long! Not the state; it's fine. The word! By the time I say "One Mississippi", at least three seconds have elapsed! I end up saying "One second, two seconds..."
I think all clocks are effected by gravity...a clock on the planet will run slower than one in space.
We’ve literally had cesium atomic clocks for decades - what’s the fuss??
I just want affordable dental care.
How long would an experiment even have to run to figure out if the speed of light is variable? Feels like humans will be so far gone we won't even be a memory anymore....
👋👋
Engagement engagement engagement
Can't wait for the development of nuclear clocks so we can get only fans streams in real time
Harnk
crazy
I personally think seconds are far too long
Why?
I'd find this fascinating if I was being told this is what Geordi and Data have been up to in their spare time, but we don't live in Star Trek land... because ego-scientist waste their time (ha, oh and ^ there's another) with sh-tuff like this.
... Do.. you have. a video showin' what Data is up to?
... where Geordi keeps working in quotes from the "Reading Rainbow" song.. songs?
fallout clocks
Cool, I now have some credibility to my made-up career of Deep-Sea-Nuclear-Watchmaking-Technician that I dreamed up in high school. 😂
🧠 hurt
Is he ok? I've never seen him in a hat
He has cancer. He's doing pretty fine but did have to do chemo, so, hair loss
@@awaredeshmukh3202 I found out when i watched his chemo episode the other day. Been watching Hank for years. Never paid attention to how recent the videos were, so I really had no idea. Glad to hear he's ok. Thank you.
wow, you really baited this story without delivery the goods. Which frequency band was obtained??? 5:10
Where did your hair go
In case you´re serious (sorry if I´m steping on a joke): Hank had chemo for Hodgkin lymphoma. Seems to have been sucessfull.
@@CL-go2ji well I hope he's okay. Thanks for letting me know. I was genuinely curious. I'm not on here very often and I'm not on social media at all so I didn't really know what was up. I hope he gets better!
This is where science is now. Propose more pointless projects instead of putting actual effort into solving actual problems...