How an atomic clock works, and its use in the global positioning system (GPS)

[@paulchristian5375]

Man, having to adjust your clock one second every few million years is so inconvenient.

[@ShauryamAkhoury]

Ikr!! It's soooo annoying

[@yououtuber4176]

I hope that I will still live in the same time zone.

[@la33s]

@Anant Tiwari its okey you will someone to interact with some day

[@v4v819]

It's more inconvenient then resetting your regular clock every year... How do you set a reminder for every few million years... What do you set a reminder on, for every few million years... In 10 thousand years, everything presently including our bones will be dust...

[@56independent42]

this is why i ise a wifi clock. someone else adjusts it for me.

[@BudgiePanic]

These are hidden gems hiding in youtube

[@sandeepr1253]

Trippie Redd autistic shoota #iwillslap6ix9ine Great .....

[@sunilsoni3310]

Those hidden gems were all there was on youtube a few years ago. Those gems that are now hidden are what made youtube big.

[@Fondofmelobster]

If they weren’t hiding they wouldn’t be hidden

[@michaelknight2342]

More hidden gems: Ben Krasnow, Sam Zeloof, Jacob Collier, Apartment Sessions, Adam Neely, Technology Connections, Strange Parts, Styropyro, Michael Reeves, Marc Rober, SeanHodgins, Explosions&Fire, Tech Ingredients, SmarterEveryDay, AlphaPhoenix, Nighthawkinlight, ElementalMaker, Abroad in Japan, tesla500, Usagi Electric, Daniel Schiffer, Tom Scott, The Thought Emporium, Charles Cornell, Christian Jackson, Casually Explained, mikeselectricstuff, Medlife Crisis, Jacob Mann, Jeremy Fielding, muteFPV, Bob Reynolds, Carl Bugeja, DOMi & JD Beck, MIT OpenCourseWare, Tom Stanton, NileRed, Flavor Lab, :3ildcat, Stuff Made Here, JYMV

[@BudgiePanic]

@@michaelknight2342 I recognize about half of these :) You should add Ben Eater to the list, former Khan Academy contributor, now making the best videos about low level computer operation I've ever seen.

[@Dorkus89Malorkus]

It seems so simple after somebody already invented it... I guess that's the catch. The best engineers are the ones who know their science but who also are slightly on the creative side.

[@Listoric]

John England j

[@rhettorical]

There's an old tale of some detractors who were razzing Christopher Columbus at a party, claiming that his accomplishments were of no special note since "Everyone was visiting the New World these days, it's easy." He challenged them to stand an egg on end. They naturally failed to do so, and asked him how he would do it. He proceeded to smack the egg's end on the table so it deformed enough to stand upright. "You think it easy, now that I have shown you," he said.

[@jakobhayden3976]

Cesium atom ions existing in different forms being separated by magnets only to be reenergized by radiation to oscillate a piece of quartz utilizing the piezoelectric effect. Ah so simple

[@alphabeta3528]

@@jakobhayden3976 ye. That's why inventors are very precious

[@troll2637]

​@@ListoricRichard America k

[@thegardenofeatin5965]

"I'm going to show you how the first atomic clock worked. I'll start with jello."

[@MrArchDelux]

Thanks, I have got speakers & sight you know.

[@ProctorsGamble]

dry. very dry. like good martini.

[@siukslessiuksles1894]

Who does that?

[@MrVosh-nj2lc]

Editing is great until you start cutting through the bone.

[@pennise]

There's always room for Jello.

[@wiscgaloot]

I'm a high school science teacher, and I'm very impressed with how clearly you narrate your videos. You also pick some of my favorite physics subjects to explain!

[@flat-earther]

hi wiscgaloot, have you become a flat earther yet?

[@-se]

I don't know what you're talking about. But it sounds smart, so here's my like

[@madingahmar4420]

mangaka08 lol

[@this_is_patrick]

@@mangaka08 bruh that's a pretty hood way of explaining things lmao

[@mothhunter2337]

is your pfp fry em up?

[@melody3741]

I hate when people do this. If you actually bothered to watch the entire video, it’s only five minutes, he will literally explain it to you piece by piece and you will understand it and can stop making these stupid comments.

[@-se]

@@melody3741 it's just a dumb joke, don't read too much into it. Loosen up that butthole and have fun a little bit with your life, ❄️.

[@br6768]

Explaining it is the easy part. Someone had to figure all that out. Insane.

[@domjubgwefer]

How do people figure this shit out?! Blows my fucking mind.

[@byronwilliams7977]

u just got scienced :D

[@loupax]

domjubgwefer they were not screaming "I'm never going to use this stuff in real life" in school for once. Probably helped

[@megakeenbeen]

domjubgwefer Yeah, Science

[@puncheex2]

megakeenbeen Yeah. And engineering.

[@dirkwalker9686]

Tiny advancements and discoveries really stack up. One person couldn't do it, but together the global scientific community can do mind blowing things over time.

[@ryangis431]

"I'll tell you how an Atomic Clock works." "Lets look at some Jello." the timing on that was perfect lmao

[@tompycz2225]

The timing was as perfect as the atomic clock's

[@BlackJavaBean]

Nothing better than starting your day with an Engineer Guy video! I really enjoyed the look back at how atomic clocks were originally designed. I bet that had to be a feat during their era, I assume they had to use a lot of analog electronics to keep their detector circuit going. Also a great tie-in to a ubiquitous piece of technology, GPS.

[@androidemulator6952]

The mark of a great, nay brilliant teacher, ..taking complex subjects and making them both easily understandable , and entertaining. Thank you , once again Bill. :)

[@petergreenwald9639]

Makes Bill Nye look like the slacker guy. This guy is obviously a skilled and knowledgeable engineer who knows his stuff and stays out of camps he isn't qualified to prance around in.

[@GWhizard]

Still, the most interesting channel on yt. This guy's voice can turn my head in his direction.

[@HenryLahman]

not where I expected to him start "The way that atomic clocks works amazes me, let me explain how the very first one worked. I'll start with Jello"

[@ZteveW]

you lost me after, the jello but I loved the vid. LOL

[@injusticeanywherethreatens4810]

Take a high school chemistry and physics class, then come back to it.

[@grahaminatorca85]

+ThatOneEngineeringStudent You come off as someone with their nose up in the air talking like that. Yes I took high school chemistry and physics.

[@V0YAG3R]

ThatOneEngineeringStudent Walk the talk! Make your own atomic clock then come back to us and show the world how, with your high school level alone of chemistry and physics, you really grasped it all 👌🏻

[@Phoenix-dh6ct]

Put video on quantum

[@CVSBobby]

I love your appreciation for other's ingenuity. I'm humbled by your humility.

[@evansdad4186]

I just wanna say I LOVE your videos!! Thank you for putting these out for the world to learn... I love the engineering perspective you give on things, you've made me look at a cell phone differently ever since I'd seen that video. Keep up the good work!!

[@Fr3dd1S]

not sure how people don't follow this guy, he's explaining the stuff incredibly clear and as simple as possible, i mean, i'm from finland i understand everythign he's saying..., i went to school tho, did u? ;)

[@RoloFilms]

"About the size of a quarter" is taken very broadly I see XD Nice vid, as always.

[@FanboyFilms]

I was gonna say a half dollar would have been closer. But those aren't very common these days.

[@violaisreallycool]

I love how you presented the concept! Nice animations and analogies. Thanks for the quality content:)

[@madgoblin464]

Bill Hammack I bought your book a few years back. I love it so much. In fact it was the only book I ever so cling to it. I hope you will make more books. I will buy them.

[@carolynmmitchell2240]

Gary Yong Kah Joon he does, he has a few.. he has one on a blimp

[@lohphat]

GPS calculations also have to factor in general relativity for accuracy. 1) The velocity of the satellites slows down their clocks AND 2) Their position within Earth's gravitation field speeds up their clock. Without these corrections the results would be off by a hundred meters laterally and thousands of feet vertically.

[@samtzam3774]

This happens because the physic laws is related to the frame of observation. (General relativity) The error actually with not correction is some cm/sec.

[@ayeshakhan796]

Did Einstein consider the atomic clock (or analog clock) in his relativistic time dilation because of gravitational distance? How do these two devices are differentiated against gravity?

[@luckycrits]

"The way that atomic clock amazes me... let me explain with how the very first one worked... I'll start with Jello." - You sir are a comedian and a scholar.

[@ItchyKneeSon]

I tried to buy the book from Amazon.com here in Japan, but they never sent me a confirmation email with the special number used to pay for it at a convenience store (easy way to pay w/cash in Japan). So, the seller ended up canceling it, to my dismay. I know this isn't the forum, but watching this reminded me. Thanks for all of your videos!

[@elizabethbeneck2709]

A cesium atom in an atomic clock beats 9,192,631,770 times a second.

[@happmacdonald]

Yup, thank you for pointing that out, Elizabeth. And for the readers at home that number is not rounded or an average. It is *absolutely exact* because we actually define the time interval we call a "second" to be precisely that many oscillations of Cs133. Even when the theory of relativity predicts that spacetime distorts, dilating time relative to another observer, both the standard unit Second and the frequency of Cs133 are dilated in kind so you simply wind up with more or fewer seconds (and Cs oscillations) measured by the out of sync observer per unit of their own time. :3

[@cheongziyong8871]

+Happ MacDonald Isn't time defined by the speed of light? Or is that distance I'm thinking of?

[@cheongziyong8871]

+Happ MacDonald Isn't time defined by the speed of light? Or is that distance I'm thinking of?

[@happmacdonald]

Actually, you'd be surprised but time is better defined by the causal propagation of a process having the capacity to move *slower* than light (that is, slower than uninterrupted causality) through space. Nonetheless, the question of "what is time made out of" (answer: it's made out of the opportunity for systems to causally evolve, and it dilates in different circumstances because the opportunities for systems to evolve are impacted by relative velocities and warped spacetime geometry) is different from "how do we humans choose to standardize our measurement of it" (answer: in units such as Plank Time, and seconds which are exact multiples of vibrations of Cs133). :3

[@xImBeaST12321x]

the speed of light establishes the distance in SI... i dont remember the exact number but yeah a meter is the distance that light travels in a couple billionths of a second.

[@isaac.zeitgeist]

its satisfying to see such an idea being so perfectly explained

[@MSpeedThree]

Ya, well, that's just like, your opinion, man.

[@ilovemykitties84]

lol the dude!

[@oneminutefixed5003]

Adam R that jello really tied the lesson together

[@furryz666]

OneMinuteFixed "theres always room for jello"

[@fernandaabreu5625]

Furryz "Grandma's chicken salad" I'm sorry, I just couldn't help myself.

[@TestTheAcid]

sad

[@bozhijak]

In the Coast Guard i was stationed at a LORAN-C navigation station that utilized cesium clocks. At the time they were the size of a small filing cabinet. Now you can fit one in your hand. Amazing.

[@CheapSushi]

music is a bit too loud compared to the speaker

[@MaxHohenstaufen]

This guy has the most amazing voice for an engineer. His videos are too awsome.

[@Reloykaotica]

you look like luke skywalker does now

[@batfan1939]

So it's not just me? BTW, Mark Hamill is also the voice of the Joker. Has been for twenty years. Batman: The Animated Series (and any cartoons, films and games related to it), the first few "Batman: Arkham…" games, and DC Universe Online to name a few.

[@linkinparkfan0459]

JREADY and i thought i was the only one..

[@aura666]

wow, i didn't know Luke sky-walker was a great engineer, you learn something new every day.

[@yoramstein]

Great easy clear explanation (specially the feedback system that controls the cesium/ quartz fork). Thanks.

[@trevpr1]

Best explanation I've found on YT.

[@cherrypepsi2815]

"About the size of a quarter" *is about the size of an Eisenhower dollar*

[@ralanham76]

"ABOUT"

[@cherrypepsi2815]

@@ralanham76 "about"

[@hindugoat2302]

@@cherrypepsi2815 if engineer guy is so smart, why cant he engineer himself a decent haircut ?

[@cherrypepsi2815]

@@hindugoat2302 ouch that's gotta hurt

[@dennisk5818]

Great presentation, simple but to the point.

[@phooesnax]

Glad you are back. Watched the first series and enjoyed it. Keep up the good work!

[@MattPhilips314]

Great video, but i was wondering: why is a Cesium atom with a higher energy electron deflected by a magnetic field?

[@puncheex2]

Matt Philips AKA Percival The higher energy cesium is ionized more - i.e.. it has lost more electrons, giving it a more positive charge.

[@subh1]

puncheex2 I think the ionization is the same (they don't lose electrons, but the electrons only jump to higher energy level). In the different energy levels it's the magnetic moment of the electrons in the two states that are different though (a quantum mechanical property, because the electrons are not point particles, and are instead wave functions).

[@donantoniodilampedeusa259]

No - the magnetic moment of the electron in the lower state is antialigned with the nuclear magnetic moment, ie N lines up with S, in the upper state the electron's N pole is aligned with the N pole of the nucleus making an overall bigger magnetic moment for the upper state.

[@YanivGorali]

This is becoming one of my favorite channels. Thanks alot!

[@Tarik360]

I'm a bit tired and I am not sure if I got everything immediately, but I'd like to ask how long it lasts before you're going to need to change a part for maintenance of such a device.

[@Nosirrbro]

No moving parts and no exposure to outside air combined with microscopic scales means that, discluding being shoved into the center of a brick of C4, the atomic clock never needs any fixing.

[@Tarik360]

+Nosirrbro That's amazing! Are they also waterproof?

[@Nosirrbro]

Tarik360 Uhm, I wouldn't think so, but I guess you could waterproof the casing of it.

[@Tarik360]

+Nosirrbro That is an even better way of doing it! Good night!

[@knowmankind]

Easy to listen to. Great presentation. More please.

[@vaseemmehrancp9372]

Very very informative .. This video deserve more viewers

[@Tomyb15]

But then how is this related ot the SI definition of a second or the caesium standard? From Wikipedia: "A caesium standard or caesium atomic clock is a primary frequency standard in which electronic transitions between the two hyperfine ground states of caesium-133 atoms are used to control the output frequency." It also says that a second is defined as exactly 9,192,631,770 transitions of those two states. I don't see how that number of transitions between the low energy state and the high energy state is important for the functioning of this atomic clock.

[@davidbeyondplus2587]

From what I remember from physics class is that the SI units is determine by the time light takes to travel a certain distance. Since light is a constant, a frequency or pulse using light can keep a measure of change which is time. A long time ago Galileo measured time using his heart pulse.

[@shanmugavallielangovan7928]

never believe wiki.its wrong on one way or the other

[@MC-mx1mt]

David Beyondplus but my reference book mentions the caesium atom's one.

[@danav3387]

Wikipedia is NOT a recognized nor reliable source for correct information about anything...

[@karlvs2616]

"No Jello® was harmed in the making of this video"...

[@massivemuscles85]

The background music for this channel always reminds me of a Legend of Zelda game. It just adds to the awesomeness of it

[@jackmanhardt9909]

I'm pretty sure that music is from one of the Pokemon Mystery Dungeon games

[@windiahacker]

never stop making these

[@micahphilson]

You say "the most accurate of atomic clocks", and though I know this is pedantic, you'd really rather say "the most *precise..." Accuracy of a clock is in how you set it. Precision is its timekeeping abilities, that it will stay perfectly consistent. If you don't reset your clock over Daylight Savings, it'll be inaccurate by 1 hour, but it could still be perfectly precise for thousands of years.

[@micahphilson]

For instance, my clocks and watches are mostly very imprecise (especially my watches; they're super cheap, but fun), but they're all set very accurately, because I'll wait upwards of a minute just to set them exactly to the second from my computer or phone, so that they're all withing a couple seconds of eachother. Insofar as the source time I get from those is accurate, so are the rest, though some may veer off time after awhile.

[@robertromero8692]

If it's not very precise, it won't be very accurate. So it's valid to say that it's losing accuracy.

[@KurtBob]

I just found you like Thursday, and oh man, I'm in love!!!

[@X-OR_]

It's Like a Phase Lock Loop !!

[@Neolith100]

This series is getting so good I might just buy the book!

[@shanmugavallielangovan7928]

man you're awesome in explaining the stuff

[@hosmanadam]

Fascinating. But don't we need to use an even more accurate clock to know that we calibrated this one correctly? Wouldn't we need one that loses 0s in a quintillion years to determine that this one loses 1s in 138,000,000 years?

[@2006mct42]

That's a good question. I think that is done theoretically. The definition of one second is theoretical. So error of the practical clock is estimated compared the theoretical definition of one second.

[@johnnytremp]

2006mct42 no, the definition of a second is defined by the amount a cesium atom oscillates.

[@2006mct42]

johnnytremp Yeah I know that definition is about counting the oscillation of the atomic states of cesium but the practical problem is about error that builds up over time in the clock. So what I wanted to say is that a perfectly accurate clock is not needed to estimate the accuracy of another clock. We should just know the definition of the second. They just do the math and calculate the probable error.

[@arooobine]

I think what they do is compare a bunch of cesium clocks against each other and statistically calculate the error.

[@AnanyaGupta]

I absolutely love your ending theme music.

[@CrazyCow500]

My fucking brain!!!

[@fex144]

you brain is fucking?

[@Nosirrbro]

He has two brains: His brain for fucking And his normal brain He has exclaimed, for no particular reason, the existence of his brain for sexual intercourse.

[@mikakorhonen5715]

CrazyCow500 Einstein's fault! BTW Einstein liked fucking.

[@Hollyweed1]

Great presentation and nice music.

[@Skeluz]

You are absolutely correct. General Relativity tells us that time ticks slower near a great gravitational force.

[@01rai01]

Also thanks to special and general relativity

[@stevencp]

yeah, notice he skipped over the time difference of satellites because of relativity... that would have lost to many people!

[@fensoxx]

I miss these videos I wish they’d make more

[@engineerguyvideo]

I will

[@Redstonejiz]

you lost me at 1:35

[@user-wq9mw2xz3j]

you should understand that with just normal high school atomic physics

[@BushCampingTools]

Finally a great explanation! Thanks for posting, I'm subbing to your channel. My 10 YO asked and I couldn't explain it like you did.

[@BSDOWNZ]

You need to make move videos. I command it..

[@frogsoda]

Bill, you start this video by saying you want to show us the most amazing thing. That could apply to pretty much all of your videos. And what makes it even better is that you do it in a way that someone with average intelligence can understand and without talking down to them. Thanks.

[@CornetBabe]

Bill I love your videos and put a link on line every friday to one of them for my students. However, watching series 4 you seem to have lost your sense of humour. Bring back the fun quips at the end at least please. They are still brilliant but leave folk with more of a smile if you let us see your smile. Thank you for all you do.

[@Schontaylor]

This went over my head but would sure love a longer presentation perhaps with a neophyte asking questions. Ideally me 😵‍💫

[@f1urps]

"About the size of a quarter" The chip is at least twice the size of that quarter he held up.

[@eclipsioredstoneyt9580]

it amazes me that the signals travel so fast. Simply amazing.

[@nunyabidness117]

Yeah that's nice but I'm still proud of my 3rd grade baking soda and vinegar volcano.

[@bohanxu6125]

This channel is perfect for physics students who know very little about engineering.

[@coriscotupi]

A GPS receiver needs *THREE*, not "at least four" satellites to locate its positron on the Earth. And the "one satellite to correct the time of the receiver, three to locate its position" is utter BS - time is deduced from the location solution even with only three satellites available. If four satellites are available, a 3D location + time will be computed (latitude, longitude, altitude, time). If only three satellites are available, the solution will be 2D so altitude will not be computed - but the location and time will (latitude, longitude, time). This is basic stuff widely available in books and online for many years, there is no excuse for spreading wrong information on a presumably technically-oriented KZbin channel.

[@cultpony]

corisco tupi You need four satellites for accurate measurements of position. Of course, you can get a position with only three satellites and possibly only two, but do you know why? Three satellites will result with two points and you have to choose which one is probably the right one. You make assumptions. You can, for example assume that you are, on average, about 6371 km from the center of the earth and take that as basic altitude. But that isn't always true. This is an average value that will be wrong most of the time, for example when you are on a mountain. When you are closer to the poles you will be 6357 km from the center of the earth and near the equator it will be 6378 km. If you have some cheap GPS receiver it will, of course, make that assumption and probably get a result that is somewhat right but still off by a bit. But if you are in a plane you need precise results and assumptions of altitude won't work. You need all four sats visible to calculate position, altitude and time. The fourth sat increases the accuracy of your position and gives additional data about it, with only three you are just making a wild guess and hope it's right. Technically you can also make a good guess where you are with only two sats in the sky but it will be horribly inaccurate. TL;DR You are wrong. You can't get a position out of three satellites. You either need a fourth satellite or make an assumption of your height.

[@coriscotupi]

MrEyecikjou Sorry, you are wrong. First off, you *CANNOT*get a position fix with two satellites, the minimum is three. Also, the difference from a position fix from 3 satellites to 4 is that the former gives a 2D position (no altitude information so the fix will be on the geoid surface, approximately sea level - but latitude and longitude WILL be acurately given), while with 4 satellites you get 3D (lat, long, alt). Of course, the more satellites, the better the accuracy but this holds true for any increase, not just from 3 to 4 satellites. I.e., 5 satellites gives a better accuracy than 4, 8 is better than 7, etc, assuming the satellite geometry at the moment and receiver location is adequate.

[@cultpony]

corisco tupi If you make a few more assumptions you can work out a position with only 2 sats, it's just VERY inaccurate. And you always will need an altitude when calculating with 3 satellites, as 3 sats resolve to 2 possible positions, additionally the position itself is less accurate.

[@coriscotupi]

MrEyecikjou 3 satellites resolves to ONE position on 2D.

[@cultpony]

corisco tupi 1 sat gives you a sphere, 2 give a circle, 3 give 2 points and 4 1 point, look up the math.

[@HeyJD123]

This was great. I love the random trivial facts you put into the videos.

[@georgeburdine5660]

This guy is fascinating , good stuff man.

[@engineerguyvideo]

Thank you

[@hroman5]

An 8 year old video that is every bit fresh now!

[@BeatifulSadness]

I use these videos to further my knowledge of physics and they sure work. Thanks a lot

[@neilvermeulen5283]

Interesting Bill. Thank you sir.

[@miffyn1737]

the jello really effective to me. i have watched various videos with the same topic but I don't understand them well. the jello helps me to get the idea better. thanks

[@honestinsky]

Excellent video, thanks for posting, much appreciated. A+

[@RafaelRamirez-vk4vu]

I'm almost clicked on the link for that book but, I'll wait to have couple more videos down. Those references for the book are getting more interesting with every video though....

[@alejotorres181]

Great video, loves this deep explanation video. Only thing i would like on 4:32 to clarify couple things: - How the satellite know its own location, when sending it to the Receiver? - how does the Receiver knows the the signal travel time? I would assume it goes back to the satellite location, *- so that means the Receiver also knows its own location? How ? - The part of sphere around the satellite is difficult to understand for me, I do understand that the three spheres converging will indicate a point. And because the satellites are going so fast, a millisecond error translate to scale error of thousand of Kilometers. Thank you for your time and dedication. Please keep blessings us with your videos.

[@alejotorres181]

Rewatching the video multiple times, back to the problem of me understanding the sphere around the satellite; is that the scale of the images makes my brain think that the small earth next to the satellite means that the satellite is very far from the earth. But thinking about what you say about the Receiver knowing it is inside a sphere generated by the satellite, makes me realize that the stelitte must be close to earth. Sorry if this sounds stupid but i still want to share it. I like when my brain gets to work.

[@alejotorres181]

I understand everything know, 😅

[@TheMagickdude]

Your videos make my head hurt, but in a good way.

[@potawatomi100]

Well done Bill.

[@09052010boo]

As always, a superb explanation.

[@MrMizo1997]

I watched Some of ur vids recently and i love them all ......... i wish u never stop making vids .... god bless u

[@BrunkenDrawler]

Watch the Quarz video referenced in this one at 0:53. The Quartz oscillator at 2:34 helps keep the time.

[@nathanas64]

Phenomenal explanation!!

[@VulpisFoxfire]

Actually, the high-energy ones are the ones that get discarded in the first place--the low-energy ones are kept and then excited into a higher energy state--it's when that excitation *stop* that triggers the jolt to the quartz.

[@doorguru168888]

I was wondering how that worked.. and after watching this, I still am.

[@vishalkrishan8988]

very good illustrated you in this video even a lay man can understand it thanks for uploading this video 👍

[@pdmepma7689]

Your voice is great and the way you explanation I always like

[@garyy.7]

My mind is blown thinking about how hard it must be to make this on a large table , while people manufactured this in tiny shelf clocks

[@angryIndian26Jan]

Great explanation

[@KalimaShaktide]

Damn why did I forget about that...thanks for the reminder.

[@ramy0708]

Follow up question is on the current from the detector to the oscillator ? What does that current do ? Does it make the quartz to vibrate/oscillate ? Also, i am guessing the feedback loop is used to bombard the quartz oscillator and that wont make it slow down. The reason i am asking this is at 2:34, he speaks about oscillation decaying, how would that decay if there is continuous feedback from the detector to the oscillator ?

[@DudokX]

wow the basic concept is quite simple!

[@KowboyUSA]

Accuracy to "within 3 feet" is all that's needed for a F-104 Starfighter to drop a 36 pack box of Hostess Ding-Dongs into Michael Moore's mouth from 6,000 feet.

[@thesenate2718]

John Ratko you over did-it, it wasn't that funny.

[@Frankx520]

Great video. The GPS is actually experiencing time travel while in the space, the time difference should also be added in order to get the precise location.

[@daniellefreyaold6099]

you are speaking of course of relativity, and yes, it is actually written into the digital standard.

[@carolynmmitchell2240]

Albus Bumbledoof yeah relativity is bullshit theory.

[@operatoryeehaw7138]

I don’t know what he is saying but I like the way he says it

[@Cr4yn0r]

Is anyone else confused by the illustration? At 3:45 he says circumference of a circle but highlights the surface area. Also the illustrated location is inside the surface area, but should be somewhere on the circumference. So what is being said is correct and the illustration is misleading since the overlapping parts of two spheres should indeed be the circumference. Or am I missing something here?

[@HeyMurshid]

On heating Cesium Chloride, the stream that comes out contains both low and high energy ions, the low energy ions ARE actually discarded in the first place...

[@stillkickin3919]

Lime jello obviously has certain properties.

[@psandborn]

My impression is that the "losing 1 second over millions of years" just illustrates the accuracy of the clock. It's like saying 1 mile per minute vs. 60 miles per hour. The accuracy of losing 1 second per x million years is the kind of accuracy you might need for applications like GPS. Bottom line, I think you're right: we don't really expect to use the same device over millions of years.

[@etbadaboum]

Thanks. Good video by the way. You can maybe make an update with the Galileo system (or future GPS updates) which has an even more precise method to measure time. No quartz involved.