How cold can it get?

[@FireAngelOfLondon]

OK, now I would love a video about negative temperatures please! Thanks for this one too, I had no idea they had come so close to absolute zero.

[@Quantanaut]

From what I know, you can only have negative temperature in a system that has a maximum energy limit. If there's a maximum energy, then that max energy state will have low entropy (since there's only one way to have that max energy), and due to how temperature and entropy are related, the math works out that some states have negative temperature.

[@cghc9935]

-20 degree Celsius.

[@michaelsommers2356]

And the video has to have lots of songs.

[@txmike1945]

minus 40. You have to guess if it is degrees F or degrees C.

[@michaelsommers2356]

@@txmike1945 By negative temperature, he's talking about the Kelvin scale.

[@austincrain8218]

You can’t drop a gem like “negative kelvin” without a follow up video! Looking forward to it!

[@feynstein1004]

Sixty symbols, my man. Here's the link: kzbin.info/www/bejne/r4XIc4imh5ZqiNk

[@live_long_and_prosper]

How about "i" imaginary temperatures?

[@feynstein1004]

@@live_long_and_prosper Is that even possible?

[@thegorn]

No such thing as negative Kelvin

[@feynstein1004]

@@thegorn Just watch the video I linked to

[@andrewpinkham9904]

i like your sense of humor.i also enjoy the way you simplify the concepts without coming off as condescending.Thats a trait of someone that's genuinely intelligent

[@shadow404atl]

Never stop making these videos Dr. Lincoln!!! I have learned so much with your down to Earth teaching style. And from that I dug deeper into topics that intrigued me and learned so much more. The way you taught relativity and gravity finally got me past the hurdle I had been having fully understanding those concepts and their implications. Thank you so much and see you on 12/9/22. I'll be prepared with lots of questions if there is a Q&A.

[@turboenterprise790]

Dont stop the videos man. Keep them rolling

[@tigertiger1699]

What is an absolute privilege.🙏🙏 for all of us who never went to uni.., and certainly no where near a lab.. to get to hear from / share in Fermilab.. way cool👍… cheers

[@David-di5bo]

Pretty sure the coldest spot in the universe is my bathroom floor in the morning.

[@kennyshullai8753]

Hear hear.

[@seriousmaran9414]

I remember visiting someone in the winter in the 1960s. Unheated outside privy with snow on the ground. There was ice inside but I defrosted it a bit.

[@nvkulk]

No…toilet seat

[@surfingonmars8979]

You’ve never experienced a wife’s heart………….

[@David-di5bo]

@@surfingonmars8979 🥶

[@bobbyd.roberson5588]

I’d absolutely love to see a video about negative temperatures

[@Epoch11]

Here here!

[@petergreen5337]

Me too very interested.

[@ArawnOfAnnwn]

So basically negative (Kelvin) temperatures have to do with the probability distribution of the particles in the substance. Ordinary matter will have the distribution wherein particles are far more likely to be in the lower energy states than higher ones, so the majority of particles are low energy with a minority at high energy. Negative temperature happens when this distribution is reversed, so now particles being in high energy states in more likely and so the majority of them are high energy. Since the flow of energy is from high energy states to lower energy states (thus why hot stuff cools), the flow is from negative temp stuff to positive temp stuff.

[@jamescarlisle3770]

okay Dr Lincoln you've raised a real hair on my head and I'm absolutely bald, when you mentioned negative Kelvin temperatures being hotter than the coldest Kelvin temperature. please tell me what that might mean if applied to the earliest moment in the universe.

[@itsROMPERS...]

This is only theoretical and cannot exist in nature.

[@jacoblashley4018]

Definitely want to know more about negative temperatures now!

[@petergreen5337]

Same here.

[@ArawnOfAnnwn]

So basically negative (Kelvin) temperatures have to do with the probability distribution of the particles in the substance. Ordinary matter will have the distribution wherein particles are far more likely to be in the lower energy states than higher ones, so the majority of particles are low energy with a minority at high energy. Negative temperature happens when this distribution is reversed, so now particles being in high energy states in more likely and so the majority of them are high energy. Since the flow of energy is from high energy states to lower energy states (thus why hot stuff cools), the flow is from negative temp stuff to positive temp stuff.

[@Tomas.Malina]

Sadly, It's just a "feature" (not a bug!) Of the statistical definition of temperature, nothing extraordinary about it. Still, I agree, any video by Don is appreciated 🙂

[@feynstein1004]

Sixty symbols to the rescue. kzbin.info/www/bejne/r4XIc4imh5ZqiNk

[@NotJustBikes]

I got so annoyed that you kept mentioning the temperature in Fahrenheit, but never once mentioned the temperature in Rankine. smh

[@JayTemple]

Rankine is the Dumont Network of temperature scales.

[@mdwoods100]

I love the Fermilab videos. The presentation makes it easy to understand what are often difficult subjects

[@siddharthsingh7281]

Measuring it to be 38picokelvin is another genius.

[@luvhateluv6607]

Dude, glad you are still rockin the fermilab vids! Your articulation and humor are Absolute.

[@robertfletcher3421]

Dr. Don, we need a video to explain the other end of hot, as with Absolute Zero and the explanation of Planck Temperature. There is stuff on the Internet but a Dr Don explanation would be much better.

[@HH-mw4sq]

Two new things have been added to my bucket list. 1) A video explaining negative temperatures, and 2) Hearing Dr. Don's rendition of the Frozen theme song.

[@JayTemple]

After this video, I think "In Summer" would be more appropriate.

[@DavidBeddard]

I once saw the coldest place in the known universe. It was in a cupboard in the Physics department at Lancaster University in 2008. At they time, they held the record for the coldest temperature yet achieved. They've lost that record since then, of course, to those Rubidium atoms Don mentioned.

[@markzambelli]

" _It_ was in a cupboard in the Physics department at Lancaster University..." 'It'...? when you refer to my wife I'd rather you use her name... 😈

[@DavidBeddard]

@@markzambelli Ooph, that's cold, man! 🥶

[@colinhughes6635]

@@markzambelli g

[@sapelesteve]

I must say Dr. L that this was a very very cool video! Good seeing you back here! 👍👍💥💥

[@jasonwiley798]

Downright cold

[@tastethejace]

Fascinating! Excellent vid as always! Keep up the great work! 👍

[@petergreen5337]

Agreed.

[@duggydo]

I vote for a video on negative temperatures! 👍

[@nathanmays7926]

I’m more interested in how a thermometer is capable of measuring those temperatures, than how the temperatures were achieved.

[@markholm7050]

I also would be very interested in a video describing how very low temperatures are measured. Don Lincoln is a theoretician. We need an experimental physicist who works with very low temperature experiments to describe it for us.

[@XEinstein]

I think those temperatures are not measured but calculated

[@TheUglyGnome]

These low temperatures are measured by measuring kinetic energy of the molecules, which is in fact the definition of temperature.

[@nathanmays7926]

@@TheUglyGnome yes, but how do you measure kinetic energy of molecules at that scale? i’m not doubting it’s possible… i’m just curious how it’s done

[@rykehuss3435]

@@nathanmays7926 Probably with the lasers theyre using.

[@andresdelaguardia1536]

I'd love to see a video on how those nano and pico-Kelvin temperatures are measured. The instruments to measure those crazy cold temperatures must be as amazing as the processes to create the crazy cold temperatures.

[@donzxcv1]

probably mostly theoretical , on paper only

[@JayTemple]

Keeping in mind that heat is molecules in motion and temperature is the amount of motion per unit time, it might actually be a simple reading of (microscopic length) / time = some number of pico-Kelvins.

[@dw620]

1:56 got a smile back to school days with pupils being told off for using "DEGREES Kelvin" (being an absolute scale rather than relative). The history is more complex, of course. : )

[@nickmarsala3787]

I wish Disney would reach out to Dr. Lincoln to make educational animated videos.

[@OriginalStachuJones]

Thank you for all the effort you put into your videos

[@ruttolomeo1987]

I love the way he talks, so relaxing

[@rodtidemann7472]

Just found Fermilab this morning. What a perfect site for those of us that are curious but ignorant. Great presentations.

[@TheUglyGnome]

5:44 Nice colors picked to represent different helium isotopes.

[@XB10001]

These Fermilab videos are excellent.

[@mamamheus7751]

According to my cold-hating husband, it's blooming freezing right now, so much so that he's just put the heating on. I've got it turned off in my room, it's not that cold! Give him until January and he'll be claiming it's as cold as the CMB 😉 Excellent video as ever! I love your explanations. 😀

[@pixxelwizzard]

I was just talking to my son about this the other day and asking some of these same questions. So glad to have a video on it!

[@Tker1970]

A buddy of mine froze to absolute zero. Don't worry-he's 0K.

[@Nareimooncatt]

This entire video was a tease. Now I want to see dedicated videos on each method of cooling, negative Kelvin temps, and the quantum issues of absolute zero.

[@RichMitch]

My bedroom at the minute

[@C--A]

Get a electric blanket bud ♨️

[@josephhalwagy6435]

My warm thanks to your very cool presentation

[@RIchardBH3]

Would love to have a video on Negative temperatures. I heard about them while studying lasers, but would like to see other examples.

[@mattg2106]

Awesome Video as always 🙂

[@PopeLando]

Because you're talking about temperature technology, I keep thinking you're saying "Thermilab" instead of "Fermilab".

[@eeka_droid]

Very interesting. I would love to see a video of the professor singing "Let it go". Please!

[@Kostas_Theologos]

We would like to see, we need, a video about negative temperatures please!

[@dylanotto1675]

He explained everything in the song at the end

[@jimmyzhao2673]

I was waiting for the song at the end.

[@MatteoMarconiDaVerona]

Very interesting. It is mind blowing. The video was centered on the techniques to reach such insane temperatures. I was wondering how you can MEASURE such temperatures. It would be interesting to have a video on the techniques used for that.

[@Aegirak]

If I remember my physics course in school, you cannot actually observe absolute zero. Because the actual measurement of absolute zero would raise the temp above absolute zero. Much like the Schroeder’s cat postulation that by observing the state changes the state.

[@BillWright]

At 5:50 in the video, you state that the helium 3 diffuses into the helium 4 and that carries away energy causing the helium 4 to be even colder. Don't you mean the helium 3 to be even colder?

[@drdon5205]

yep

[@kerajit]

Yep, I also was a bit confused.

[@a.rodimtsev9446]

Good video Dr. Lincoln, thanks.

[@thaliadelafuente986]

amo estos videos. me gustaría el de temperaturas negativas y también algo sobre computadoras cuánticas y de grafeno. gracias

[@petergreen5337]

Me too.

[@conniestone6251]

YaY 🎉 Dr Lincoln is back on! I’ve missed you and your wisdom gifts.

[@Jeff-so3kj]

As always very interesting1 I would definitely be interested in a negative temperature video. How do you measure these ultra low temperatures?

[@SeraphRyan]

I can't go into the specifics (cause I dont know the exact specifics) but they trap atoms in laser beams and the laser beams cool the atom down. From what I know, the photons get absorbed and re-emitted from the trapped atom, taking excess kinetic energy from the atom too. This causes the atom to cool down.

[@sobertillnoon]

When can we expect that negative kelvin video?

[@TheRolemodel1337]

there is a video about it on sixty symbols if you cant wait 😁 /watch?v=yTeBUpR17Rw

[@helgefan8994]

Sounds like nothing in the universe can get as cold as those micro, nano and picokelvins in the lab. But isn't the temperature of super-massive black holes technically near or even below a picokelvin?

[@ScottJPowers]

Fahrenheit is actually based on the freezing and boiling points of brine, a particular ratio of a mixture of salt and water, because brine's freezing and boiling points are much more stable and consistent then that of water, who's freezing and boiling points can vary quite a bit depending on atmospheric pressure, which varies with altitude and can even vary in a single place (barometric pressure)

[@ericvilas]

it's actually just based on the freezing point of brine (Fahrenheit never considered the boiling point), as well as the freezing point of water being 32° = 2^5 so he could measure out a degree by dividing the difference between the freezing point of water and the freezing point of brine in half 5 times. Also, the difference between the freezing and boiling points of water is 180° because base 60 (thank you, Rømer scale). (technically brine was actually not the original definition: it was just a precise way to achieve the temperature he originally wanted to approach which was simply the coldest temperature ever recorded in his home city of Gdansk, which he used as an estimate for the coldest temperature bearable for a person)

[@JayTemple]

@@ericvilasScott may have just given a more precise version of what I was told. If you dissolve something into water, its freezing point goes down. 0 Fahrenheit was supposed to be the lowest that you could force that point. IOW, at a temperature above 0, water MIGHT not freeze depending on how much other stuff has been dissolved into it, but at 0, it WILL freeze.

[@fathertimegaming17]

That was the best exercise of editorial control I have ever seen.

[@ospyearn]

I'd like to strike a blow for water, and thus for the Celsius temperature scale. As a Scandinavian (like Celsius) I learned early that water is at its densest at 4 degrees Celsius thus preventing our lakes and ponds from freezing bottom up during the winter. Later in life I learned that, for its transition from liquid to gaseous state, water requires a lot more energy than it needs for its temperature simply to increase by one degree, thus making it possible to use water to put out fires. I also learned that water is vital for all known forms of life. This may all be considered somewhat mundane, but I would guess that water also has a special place in the grander scheme of things.

[@Biga101011]

Yeah he kind of swept that under the rug. Water is definitely the single most important liquid to life on the planet. Basing a temperature scale off it is very useful. I mean I don't think there is anything wrong with Fahrenheit and it has some nice properties as well. But at best that makes the comparison a trade off and not simply arbitrary.

[@Ater_Swe]

Nothing special about water? As a chemist I almost had a stroke! Water might be one of the most unique and interesting chemicals in the universe!

[@K1lostream]

"Negative temperatures are just messed up and to explain them would take its own video." Well volunteered Don! I'm looking forward to it!

[@nurkleblurker2482]

Yeah Don, we're gonna need that video on negative temperatures

[@jimskea224]

"What this all boils down to..." Great.

[@jballenger9240]

Yes more videos! And singing too, anytime. Thank you very much.

[@Happyfaceshock]

One of my favourite jokes from Futurama is when they’re on Pluto and Leela says “We’d best get inside, with wind chill it’s 20 degrees below absolute zero”

[@sgregg5257]

You might remind people that the temp at which water boils, turns into a solid, or remains liquid is determined by external pressure. You can have water boil at zero degrees F. provided there is not a lot of atmosphere.

[@Tomas.Malina]

While your thinking is based on a correct assumption, boiling water at 0°F is not possible no matter the pressure. Liquid water cannot exist at temperatures significantly below 32°F (it actually does at very high pressures, not low, because of one of the anomalies of water - the density of ice is lower than the density of water). Even in complete vacuum, you'd only get sublimating ice at 0°F. You might want to look up the phase diagram and the triple point of water.

[@TheAsdffaaa]

dr. Lincoln, you're the man. I would like to always heard deeper insights to these topic´s, like negative temps, as thoroughly as you did with relativity. I didn't know that fermilab is such a big deal. I live in Europe, an thought you are some doctor working at some "doctor facility", and fermilab was your "youtube" lab/ something "made up" name for youtube, but dammit, fermilab is the real deal 8) Absolute gold content, one of the most underrater or more likely, under-watched channels there is

[@JohnDoe-rm1kw]

Apologies in case you allready know, thers a German Dr.Lincoln Style Prof. having explained (in german) about what might happen at negative-kelvin-temps. Check out "Urknall Weltall und das Leben" channel on YT. (Mr. Gassner enthusiastically tries to explain whats goin on at minus Kelvin) 🤣

[@fps079]

Let Dr Don sing the song! LOL, wonderful ending.

[@docholiday8029]

With respect, Black hole temp is absolute zero. Subscribed just now. Great video!

[@altontacoma]

You are a national treasure, Don.

[@AlanTheBeast100]

"Negative" temperature"? Eh? OK - bend our brains please.

[@good-question7893]

All I want for Christmas is Dr Lincoln doing a negative kelvin video

[@PeterTea]

Thanks. That was really cool.

[@Novastar.SaberCombat]

Love these. 🙂 Thanks so much for creating the videos. You're an excellent presenter, too, so... I think Carl would have proudly smiled in quite a congenial gesture of intergalactic amity! 😁 🐲✨🐲✨🐲✨

[@thebrainchild1]

Whenever you upload a video and I notice it in my notification box I get Goosebumps

[@JigilJigil]

All national labs should do something similar to Dr Lincoln/Fermilab videos on their KZbin channels as well, of course on different subjects and fields.

[@JerryMlinarevic]

Thank you Don. What we mean by molecules/particles vibrating is that bonding is not in perfect frequency synchronicity. That is, the pairing electrons that create a bond do not always couple and fly off as heat and the result of this is that particles momentarily move away from each other and return when bonding resumes. This is a random process dependent upon internal arrangements and external environment. When particles match perfectly in terms of quantity (mass) and kind (bonding angles) the frequency mismatch is minimised, however external environment will still have an affect. To shield from external environment one has to implement the Schwarzschild solution via magnetic field and voila! The coldest place in the Universe. Wait a minute, isn't that a black hole?

[@SoundzAlive1]

Another video for this. André in Sydney

[@Thor_the_Doge]

Quantum mechanics is so weird that it doesn't allow synonyms to exist simultaneously: "quantum physics doens't allow for objects to be simultaneously stationary and precisely located" "stationary" means staying in one unchanging location, which means it is always precisely located in one spot, they're basically synonyms

[@andoletube]

I was disappointed to not hear about negative temperature - but even more disappointed that I didn't get to hear Don singing "Into the Unknown".

[@arrendaled]

Neat thing about temperature scales. Kelvin is the temperature of the universe, Celsius is the temperature of water, Fahrenheit is the temperature of people, and Rankine is the Kelvin form aligned to the Fahrenheit scale

[@42Hz]

Let’s imagine this: what if some civilisation appears way far in the future when the distance between galaxies is way to far to see them. And they conclude that their galaxy is the whole universe. How sure we are that we have a full enough picture today to be confident in our observations? What we could theoretically miss?

[@thingsiplay]

I think the easiest way to demonstrate what negative Kelvin means is following: Something with positive Kelvin means it is moving. Zero Kelvin means it does not move. Negative Kelvin means it is moving backwards. But most importantly it is moving.

[@cerealport2726]

Excellent video as always. I'd also like to understand more about negative Kelvin!

[@lrwerewolf]

Totally want to see the video on negative temperature and see how you'd teach the concept of population inversion. :) Also, make a separate version with the singing. We all wanna hear that!

[@WatchingTokyo]

that "0 degrees Kelvin" broke my heart a little bit, but I will let it slide because your content is so good! ^^

[@nmarbletoe8210]

is it wrong to say "Chicago is ten miles of distance from us"

[@NotKnafo]

congrats on 700k

[@TeamCGS2005]

Loved the presentation. Thank you!

[@Tommynegn]

I’m geographer but love this channel more than anything ❤❤❤ thank you 🙏

[@lancethrustworthy]

You get extra points for showing and comparing the different temperature scale systems early on.

[@r000tbeer]

So much for Don's shot at a Grammy

[@tresajessygeorge210]

THANK YOU... PROF. DR. LINCOLN...!!!

[@MajSolo]

every video I seen from this channel is not wasting any time it even goes a little bit too fast for me I am 57 but I can always rewind and go back till I get it. ;)

[@kasrasharifan]

Mind-blowing ... thank you for the informative video.

[@nyrdybyrd1702]

A little remedial for Fermilab but an excellent opportunity to show that even with simplistic information one can infer profound implications. The Planck temperature is posited as 1.416784(16)×1032 K & our average body temperature is 310.2 K (waaay closer to absolute zero); such implies astronomical amounts of time necessary for the aforementioned heat to dissipate.. without which conditions wouldn't be suitable for our existence.

[@welldoneworker]

Q: "Where is the coldest place in the Universe?" A: In my Heart

[@aarons7975]

I like these video's. Don't get too nerdy or arrogant and are very easy to understand. Thank you

[@dylanmcalister8130]

This guys hand motions are completely next level

[@starlightCataclysm]

Very interesting! I would love to see a video about negative temperatures.

[@Firefoxav26]

Haha great job on this one. Especially the cut at the end lol

[@johnsavard7583]

But you're forgetting that there's also a Rankine scale of temperature, which, like Kelvin, starts from absolute zero! (I remember first learning of its existence from a book on aviation.)

[@TCizauskas]

5:45 Yellow/blue. I see what you did there!

[@guylavoie1342]

There is also an absolute zero temperature scale using Fahrenheit degrees, called the Rankine scale en.wikipedia.org/wiki/Rankine_scale

[@MultiWeb23]

Now you made me want: - Negative temperatures - How hot can it get

[@JohnDoe-rm1kw]

(Even hotter than +infinity C) 🤣

[@sukhisingh5482]

I'm just going to say it. Negative temperature video please.

[@gandolph999]

I am now absolutely curious to understand what happens at negative Kelvin temperatures. Great video. Thawing. Thanks.

[@frederf3227]

Normal matter maximizes entropy by absorbing energy from something else. A negative object is one that increases entropy by giving up energy. Touching a negative temperature object wouldn't freeze you, it would burn.

[@aryavratbhatt1920]

Hello Dr Don! It would be magnificent if you make an splendid video on negative Kelvin Thank you very much.

[@jpsned]

It occurred to me that at absolute zero, time would stop. Since nothing would be moving, nothing would be changing, and since time measures change, we would have no time.