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.
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
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.
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 🙂
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
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.
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.
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.
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.
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.
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.
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.
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. : )
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.
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.
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.
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.
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. 😀
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.
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.
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.
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!
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)
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)
@@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.
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?
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.
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
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) 🤣
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. ;)
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.
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! 😁 🐲✨🐲✨🐲✨
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.
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.
Afaik, Lasers are a neat demonstration of negative temperatures - the negative temperature comes from the population inversion in the electron shells or something.
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
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?
I really appreciate what I have learned from you >> Science! Sciences' discoveries, inventions educations had changed all the human life better every day.
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.
All national labs should do something similar to Dr Lincoln/Fermilab videos on their RUclips channels as well, of course on different subjects and fields.
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.
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?
Very nice review. But a big problem exists. How do you measure these low temperatures? Thermocouples probably won't work - they may go superconductive. What other ways are there?
5:07 ... 5: 38 Helium 3 and helium 4 have very different properties, especially at temeratures just under on Kelvin. If you put them in a container, the two liquids separate into two layers. Then, a slowly, a bit of the helium 3 dffuses into helium 4, which carries away some energy and that can cool the remaining helium 4 even colder. This technology is calleddilution refrigeration and it was proposed back in the 1950s and first demonstrated in 1964 at Leiden University in the Netherlands. Dilution refrigerators can cool objects quite a bit colder. The physical limit using dilution refriigeration is about 2 milliKelvin which is 0.002 Kelvin. That's close enough to absolute zero that I'm not going to keep giving the Fahreheit and Celsius numbers. And these dilution refrigerators can be super pretty, as you can see here. 6:29 This one is located at Fermilab and it operates at 5.5 milliKelvin. By the way, I say that the 2 milliKelvin limit is a physical one because at about 2 milliKelvin, helium 3 changes phase and that diffusion trick no longer works. Since that trick is the one we rely on to make continuous-use refrigerators, that's as cold as we can go for what we might call physical objects- that is to say things big enough for humans to touch and manipulate. Because of the need for super cold temperatures to do quantum computing, bigger dilution refrigerators are being built. IBM and others are building big ones that should operate at temperatures under 20 milliKelvin, and my colleagures at Fermilab is building a big dilution refrigerator - over two meters in diameter - big enough that they call it Colossus - that will operate in the 10 to 20 millikelvin range. Njow, the millikelvin range is about the lowest we can go if you want to cool an acutal object and do some sort of laboratory-sized thing, but it is possible to cool small numbers of atoms to even lower temperatures. That is don to study the nature of matter very, very close to absolute zero. Using magnets to align the spin of atomic nuclei and lasers to reject fast moving atoms, it's possible to cool relatively small numbers of atom to a microKelvin, that is to say a millionth of a degree above absolute zero. Scientists at the National Institute of Standards and Technology and other facilities routinely achieve that, and often into the nanokelvin range, which is a billionth of a degree abouve absoulte zero. And the current record is held by a group of Europen scientists 8:15 who in 2021 used very trick in the book to cool 100,000 rubidium atoms to 38 picoKelvin - that's 38 Trillionths of a Kelvin. The held the temperature for about ten senconds. 8:23
You should emphasize that the Celsius scale is just a biased Kelvin scale, so the conversion between both is straightforward. Hence the Celsius scale is a way to operate with the Kelvin scale at room temperatures while still using easier numbers.
Special thing with Celsius scale is that it is in fact Kelvin scale with some offset since each degree of Celsius translates into degree of Kelvin in 1:1
Negative temperatures (in Kelvin) make perfect sense if you look at the definition of temperature, which is related to how entropy varies with energy. This has very little to do with our everyday intuition of temperatures. Fun fact: we think our nerves can detect temperature, but they can't: they can detect the flow of heat energy, which is dependent not only on temperature but on the heat conductivity of whatever we're feeling. Touch a piece of wood or a piece of metal in a hot sauna: they have the same temperature, but the piece of metal sure feels hotter.
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.
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.
-20 degree Celsius.
And the video has to have lots of songs.
minus 40. You have to guess if it is degrees F or degrees C.
@@txmike1945 By negative temperature, he's talking about the Kelvin scale.
Pretty sure the coldest spot in the universe is my bathroom floor in the morning.
Hear hear.
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.
No…toilet seat
You’ve never experienced a wife’s heart………….
@@surfingonmars8979 🥶
You can’t drop a gem like “negative kelvin” without a follow up video! Looking forward to it!
Sixty symbols, my man. Here's the link:
ruclips.net/video/yTeBUpR17Rw/видео.html
How about "i" imaginary temperatures?
@@live_long_and_prosper Is that even possible?
No such thing as negative Kelvin
@@thegorn Just watch the video I linked to
Dont stop the videos man. Keep them rolling
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
Definitely want to know more about negative temperatures now!
Same here.
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.
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 🙂
Sixty symbols to the rescue.
ruclips.net/video/yTeBUpR17Rw/видео.html
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
I’d absolutely love to see a video about negative temperatures
Here here!
Me too very interested.
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.
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.
This is only theoretical and cannot exist in nature.
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.
I love the Fermilab videos. The presentation makes it easy to understand what are often difficult subjects
My warm thanks to your very cool presentation
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.
probably mostly theoretical , on paper only
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.
I must say Dr. L that this was a very very cool video! Good seeing you back here! 👍👍💥💥
Downright cold
Fascinating! Excellent vid as always! Keep up the great work! 👍
Agreed.
Very interesting. I would love to see a video of the professor singing "Let it go". Please!
I’m more interested in how a thermometer is capable of measuring those temperatures, than how the temperatures were achieved.
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.
I think those temperatures are not measured but calculated
These low temperatures are measured by measuring kinetic energy of the molecules, which is in fact the definition of temperature.
@@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
@@nathanmays7926 Probably with the lasers theyre using.
These Fermilab videos are excellent.
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.
Dude, glad you are still rockin the fermilab vids! Your articulation and humor are Absolute.
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. : )
I got so annoyed that you kept mentioning the temperature in Fahrenheit, but never once mentioned the temperature in Rankine. smh
Rankine is the Dumont Network of temperature scales.
Just found Fermilab this morning. What a perfect site for those of us that are curious but ignorant. Great presentations.
Thank you for all the effort you put into your videos
YaY 🎉 Dr Lincoln is back on! I’ve missed you and your wisdom gifts.
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.
" _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...
😈
@@markzambelli Ooph, that's cold, man! 🥶
@@markzambelli g
Good video Dr. Lincoln, thanks.
Would love to have a video on Negative temperatures. I heard about them while studying lasers, but would like to see other examples.
I love the way he talks, so relaxing
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.
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.
After this video, I think "In Summer" would be more appropriate.
5:44
Nice colors picked to represent different helium isotopes.
Awesome Video as always 🙂
Measuring it to be 38picokelvin is another genius.
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.
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. 😀
Loved the presentation. Thank you!
I vote for a video on negative temperatures! 👍
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.
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.
My bedroom at the minute
Get a electric blanket bud ♨️
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!
A buddy of mine froze to absolute zero. Don't worry-he's 0K.
We would like to see, we need, a video about negative temperatures please!
He explained everything in the song at the end
Amazing video Dr Lincoln ❤
As always very interesting1
I would definitely be interested in a negative temperature video.
How do you measure these ultra low temperatures?
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.
I was waiting for the song at the end.
Because you're talking about temperature technology, I keep thinking you're saying "Thermilab" instead of "Fermilab".
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!
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)
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)
@@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.
Excellent video as always. I'd also like to understand more about negative Kelvin!
amo estos videos. me gustaría el de temperaturas negativas y también algo sobre computadoras cuánticas y de grafeno. gracias
Me too.
With respect,
Black hole temp is absolute zero.
Subscribed just now. Great video!
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?
yep
Yep, I also was a bit confused.
Yes more videos! And singing too, anytime. Thank you very much.
When can we expect that negative kelvin video?
there is a video about it on sixty symbols if you cant wait 😁
/watch?v=yTeBUpR17Rw
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.
Whenever you upload a video and I notice it in my notification box I get Goosebumps
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
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) 🤣
I wish Disney would reach out to Dr. Lincoln to make educational animated videos.
I like these video's. Don't get too nerdy or arrogant and are very easy to understand. Thank you
Hello Dr Don! It would be magnificent if you make an splendid video on negative Kelvin
Thank you very much.
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. ;)
THANK YOU...
PROF. DR. LINCOLN...!!!
Mind-blowing ... thank you for the informative video.
Thanks. That was really cool.
I am now absolutely curious to understand what happens at negative Kelvin temperatures. Great video. Thawing. Thanks.
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.
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! 😁
🐲✨🐲✨🐲✨
Very interesting! I would love to see a video about negative temperatures.
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.
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.
Afaik, Lasers are a neat demonstration of negative temperatures - the negative temperature comes from the population inversion in the electron shells or something.
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
Thank you very much publisher another interesting lecture.
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?
Another video for this. André in Sydney
Elegant explanations
Cold temps is a hot topic! Would love to see a vid on negative kelvin?
I’m geographer but love this channel more than anything ❤❤❤ thank you 🙏
I really appreciate what I have learned from you >> Science!
Sciences' discoveries, inventions educations had changed all the human life better every day.
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.
I just happened to read this (link shared). Would love to see you explains this. Thanks 😊
All national labs should do something similar to Dr Lincoln/Fermilab videos on their RUclips channels as well, of course on different subjects and fields.
Excellent explanation!.. thanks.
Could you make a negative Kelvin video?
Thanks so much!
This was amazing. Thank you
Very interesting, great video.
There is also an absolute zero temperature scale using Fahrenheit degrees, called the Rankine scale
en.wikipedia.org/wiki/Rankine_scale
congrats on 700k
VERY NICE PRESENTATION !
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.
Yeah Don, we're gonna need that video on negative temperatures
thanks for the video. Very informative.
that "0 degrees Kelvin" broke my heart a little bit, but I will let it slide because your content is so good! ^^
is it wrong to say "Chicago is ten miles of distance from us"
You get extra points for showing and comparing the different temperature scale systems early on.
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?
Very nice review. But a big problem exists. How do you measure these low temperatures? Thermocouples probably won't work - they may go superconductive. What other ways are there?
Magnets and lasers to analyse atom movement.
Hello. I love your videos and you were able to personally answer a question for me no one else had. How about a video on Dark Matter vs. MOND.
5:07 ... 5: 38 Helium 3 and helium 4 have very different properties, especially at temeratures just under on Kelvin. If you put them in a container, the two liquids separate into two layers. Then, a slowly, a bit of the helium 3 dffuses into helium 4, which carries away some energy and that can cool the remaining helium 4 even colder. This technology is calleddilution refrigeration and it was proposed back in the 1950s and first demonstrated in 1964 at Leiden University in the Netherlands. Dilution refrigerators can cool objects quite a bit colder. The physical limit using dilution refriigeration is about 2 milliKelvin which is 0.002 Kelvin. That's close enough to absolute zero that I'm not going to keep giving the Fahreheit and Celsius numbers. And these dilution refrigerators can be super pretty, as you can see here. 6:29 This one is located at Fermilab and it operates at 5.5 milliKelvin. By the way, I say that the 2 milliKelvin limit is a physical one because at about 2 milliKelvin, helium 3 changes phase and that diffusion trick no longer works. Since that trick is the one we rely on to make continuous-use refrigerators, that's as cold as we can go for what we might call physical objects- that is to say things big enough for humans to touch and manipulate. Because of the need for super cold temperatures to do quantum computing, bigger dilution refrigerators are being built. IBM and others are building big ones that should operate at temperatures under 20 milliKelvin, and my colleagures at Fermilab is building a big dilution refrigerator - over two meters in diameter - big enough that they call it Colossus - that will operate in the 10 to 20 millikelvin range. Njow, the millikelvin range is about the lowest we can go if you want to cool an acutal object and do some sort of laboratory-sized thing, but it is possible to cool small numbers of atoms to even lower temperatures. That is don to study the nature of matter very, very close to absolute zero. Using magnets to align the spin of atomic nuclei and lasers to reject fast moving atoms, it's possible to cool relatively small numbers of atom to a microKelvin, that is to say a millionth of a degree above absolute zero. Scientists at the National Institute of Standards and Technology and other facilities routinely achieve that, and often into the nanokelvin range, which is a billionth of a degree abouve absoulte zero. And the current record is held by a group of Europen scientists 8:15 who in 2021 used very trick in the book to cool 100,000 rubidium atoms to 38 picoKelvin - that's 38 Trillionths of a Kelvin. The held the temperature for about ten senconds. 8:23
You should emphasize that the Celsius scale is just a biased Kelvin scale, so the conversion between both is straightforward. Hence the Celsius scale is a way to operate with the Kelvin scale at room temperatures while still using easier numbers.
Special thing with Celsius scale is that it is in fact Kelvin scale with some offset since each degree of Celsius translates into degree of Kelvin in 1:1
"Negative temperatures are just messed up and to explain them would take its own video."
Well volunteered Don! I'm looking forward to it!
Haha great job on this one. Especially the cut at the end lol
That was the best exercise of editorial control I have ever seen.
Negative temperatures (in Kelvin) make perfect sense if you look at the definition of temperature, which is related to how entropy varies with energy. This has very little to do with our everyday intuition of temperatures. Fun fact: we think our nerves can detect temperature, but they can't: they can detect the flow of heat energy, which is dependent not only on temperature but on the heat conductivity of whatever we're feeling. Touch a piece of wood or a piece of metal in a hot sauna: they have the same temperature, but the piece of metal sure feels hotter.