Probably the best explanation of the Black Body Catastrophe I've come across. Not heavily burdened with math or the distracting minutia of physical concepts. Thank you. It's a bit clearer to me now.
Thank you so much for helping me understand the ultraviolet catastrophe!! I wish you were my teacher, your enthusiasm and spirit makes your lessons so interesting.
I wish someone talking about black bodies would once state somewhere in the beginning whý warm bodies radiate (EM waves). First of all because they have a temperature. (That was at least mentioned here, but I'd prefer one level deeper.) That heat causes molecular vibration, rotation and torsion. And those also effect the molecular electron orbitals in all kind of different ways, which creates EM waves, though limited to quantum levels of course. (Though that latter bit should maybe only be revealed in the next video.) And if I'm still correct, heat does nót cause electrons changing levels or does it? I thought not because that's exactly what a black body is NOT and why different stars and other objects have those specific emission or absorption frequencies, those peaks or troughs in their otherwise black body spectrum. (Although some materials have the ability to transform heat into light of a specific frequency. I wonder where that fits in.) Anyway, can anyone confirm or correct? Doc Schuster maybe? P.S. Still think it's one of the best videos concerning the topic. Don't get me wrong. ;-) P.P.S. Not all colors are from temperature! Careful there too! As a matter of facts, most of the colors in our world are not because of black body radiation. (I think.) (Consider the colors of your own drawing. ;-) )
oh yay you have a playlist for quantum physics too!! now this is how i wanna spend my thursday nights. jk i hate physics but you somehow make it tolerable and sometimes fun so thank you Doc :)
Happy to help. I hope you find something that you like as much as I like physics. It is a great joy to help people while I'm doing what I like, and I want that for you, too!
You, sir, are a superb teacher and I enjoy your videos all the way although I know some of the content already. But really now, his name is "Wien" not "Wein". Wien like the German name for Vienna. Btw, Wein in German means wine. Don't get confused :D
Really great explanation! But the thing that for me is not clear enough is why the black body "have" to radiate in all this higher frequencies so the Energy is infinite. As far as I understand, given the temperature of the body within the box this implies some radiation at a given frequency with the corresponding intensity associated, why do you have to assume that all this high frequencies are also going to be radiated?
How can color depend on temp? This means the violet letters should have a higher temperature than lets say the red letters. But this can’t be true. What’s the reasoning here? Why are the red letters produced by the sharpie not as hot as let’s say a stove top coils that are glowing red? What is the difference here? Thanks
Just for fun...I would like to share something that your reflective box (@ ~ 2:30) reminded me of..... I remember--sometime back in the '80's--I had an old Metrologic He-Ne laser I used for making transmission holograms. I was at a large house that had huge mirrors on the wall--well, we (kids then) lit a smoke bomb in the room (the best way to see the Si-Fi - looking red beam bounce all over the room--I think the room would have filled completely with solid red formed from beams if it weren't for objects in the area--You could move one object and get much, much more or less reflections all over the place. It made me wonder: What would happen if you could shine the beam in through a -tiny- opening of a room that was " 100% " mirrored inside!! Walls, floor, ceiling, etc. Anyone have any thoughts--I even considered trying it-- but too many little completions. AND...this was a
Well you can't really get wavelengths smaller than the planck's length and therefore the ultra-violet catastrophe wouldn't occur as such. Does this logic work? 9:09
pencilpen786 Sounds great as an ultimate prevention. They certainly didn't believe in a Planck length at the time that the catastrophe reared its head. The classical prediction still blows up at WAY larger lengths, before the PL becomes a concern.
You seem to have the correct idea. Electromagnetic wave of a particular frequency can be emitted at different intensities. Intensity is like power. Think of it as number of photons per second. The greater the number of photons per second, the greater the intensity. Frequency - we may look at the general definition : number of cycles per second. The greater the frequency of an electromagnetic wave, the greater the energy of its photon. (E = hf)
Intensity is the number of EM waves emitted (per second) Frequency is the energy of the photon given by E=hf or E=hc/wavelength (since c=wavelength x f)
Lastly, LOTS of confusion comes from thinking about the total conservation of energy regarding the energy you're putting INTO the black body vs what's being emitted. In other words, regardless of quantization, what happens when you increase the amt of energy put INTO the black body, in terms of what's emitted? You're saying the black body would emit MORE energy from higher frequencies, thus T max would move on your graph to the right, and your temperature of the black body would go higher. essentially, you're curve, as energy is added to the system, would grow (total intensity or power out) in the upward and rightwards directions, sorta like filling up quantum cups at the different frequencies and building on top of the cups like a pyramid. (if you think of each different-sized cup as a frequency) So your graph would look like a ballon that's being squeezed from one side only, but also growing (as temperature rises). Perhaps the biggest mistake in all these Planck videos is no one describes the full system, from adding the energy to the black body and then measuring the black body's radiation out. gosintas and gosouttas. This is how to relate to the rest of us, instead of just skipping this. Planck himself would've understood the WHOLE system, not the short-cut version always presented in lectures. This is why traditional teaching methods always suck. You've simply gotta make this stuff so Kindergartner's can understand it.
+Doc Schuster Well, at the moment in Quantum Physics, we are discussing Magnetic Dipole Moments, Spin, and Transition Rates. Then, in Astrophysics, we pretty much apply what we learn in Quantum Physics to astronomy.
The emission of a continuous spectrum of EM wave actually contradicts Quantum Mechanics and the photoelectric effect proposed by Einstein. See, if Einstein's explanation of photoelectric effect is correct, some of the photons generated by the black body (say a good piece of metal) should be able to excite an electron inside the metal so that it will leave the atom!! But electrons do NOT come out of a piece of heated metal no matter how high its temperature is! That is if the state of an electron only depends on the frequency of the light that hits it, then some photons from the continuous spectrum of EM wave emitted by a heated piece of metal should have a sufficiently high frequency and hence sufficiently high energy to knock some electrons out of the metal.
If only animals all had their own mathematical operations! "Find the manatee of 17, class." "If y = 2x, what is groundhog(y)?" I think I have a book idea I can begin with my biologist wife!
all over the place, yet somehow you hit some very relevant points about Intensity and the black box. HOWEVER, you need to really firm up if the black body radiation is coming from the outside SURFACE of the black body, or the slit of the black body. I find this to be VERY unclear in all talks about black bodies, somehow Physics teachers don't like to be very precise when describing a physical system, which is wierd, bc I could understand MATH dudes doing blurry experimental descriptions, but you'd think PHYSICS geeks would REALLY focus heavily on EXACT descriptions of physical systems. So, in short, slit emission or surface emission?
You might think so, but I'm pretty cool. Heh. Let's take a poll - how hot is your armpit? THIS is why I like the internet. My local students always look at me funny when I ask that question.
other questions not answered in your video: you don't define Intensity in terms the layman can understand. Show us the difference (in real world example) of high intensity vs low intensity (for the same temperature, and then for different temperatures). And then also you need to describe things at the quantum level, and by that I mean the vibrations of the atoms/molecules in the black body which are causing the photon emissions. If you create some simple examples, such as a two-atom black body, you can probably make your description palatable to the avg human.
Look up Pierre-Marie Robitaille's papers and presentations (Sky Scholar YT). He proved Kirchoff's law is invalid along the way to setting the world record with the first 8T NMRI. He set the bar. Everyone else plays catch up.
Kelvin did a lot of good stuff in lots of areas of mathematical physics (he calculated ship wake angles as one curious example) but he waded into some muddy waters sometimes. I think he rejected Darwinian evolution because his calculations showed the earth couldn't be billions of years old. Of course he didn't have a very balanced judgement here and with hindsight geology and fossil and biology evidence is also part of the physical universe and needed to be considered on its merits too. Physicists were getting lost until they found the radioactivity and nuclear physics and qm and stuff.
Hope u answer me 😂😂🙂my teacher told me that the black hole take all of the radiation 100%and let it out 100% in the same time and in my book say that it takes the radiation perfectly and let it out perfectly!😂😂😂my english not good but try to understand me😂😂❤️
Probably the best explanation of the Black Body Catastrophe I've come across. Not heavily burdened with math or the distracting minutia of physical concepts. Thank you. It's a bit clearer to me now.
I've never laughed and learned so much at the same time before. Your videos are awesome!
This is the most clear explanation I have seen on the whole internet. Thank you so much.
'When you're looking at your computer screen... well not your computer screen. Damn it!' made me laugh hahahaa
Lucy Akehurst Hi
Lucy Akehurst Hi
Thank you so much for helping me understand the ultraviolet catastrophe!! I wish you were my teacher, your enthusiasm and spirit makes your lessons so interesting.
Yay!
@@DocSchuster It's Morley and Wien, you misspelled their names.
This was so entertaining, yet educational. Thanks for helping me with homework :D
You make more sense then my Kaplan books! I will now refer to your videos for confusing physics phenomenon such as this...and optics lol! thanks!
Morley. I don’t wanna talk about it. Dang it! I love the funny high-energy approach.
I wish someone talking about black bodies would once state somewhere in the beginning whý warm bodies radiate (EM waves). First of all because they have a temperature. (That was at least mentioned here, but I'd prefer one level deeper.) That heat causes molecular vibration, rotation and torsion. And those also effect the molecular electron orbitals in all kind of different ways, which creates EM waves, though limited to quantum levels of course. (Though that latter bit should maybe only be revealed in the next video.)
And if I'm still correct, heat does nót cause electrons changing levels or does it? I thought not because that's exactly what a black body is NOT and why different stars and other objects have those specific emission or absorption frequencies, those peaks or troughs in their otherwise black body spectrum.
(Although some materials have the ability to transform heat into light of a specific frequency. I wonder where that fits in.)
Anyway, can anyone confirm or correct? Doc Schuster maybe?
P.S. Still think it's one of the best videos concerning the topic. Don't get me wrong. ;-)
P.P.S. Not all colors are from temperature! Careful there too! As a matter of facts, most of the colors in our world are not because of black body radiation. (I think.) (Consider the colors of your own drawing. ;-) )
Thank you so much! Your video was very helpful at explaining!!!
oh yay you have a playlist for quantum physics too!! now this is how i wanna spend my thursday nights. jk i hate physics but you somehow make it tolerable and sometimes fun so thank you Doc :)
Happy to help. I hope you find something that you like as much as I like physics. It is a great joy to help people while I'm doing what I like, and I want that for you, too!
Hopefully your students know what an amazing professor they have!
This is the most underrated video I have ever seen....
You, sir, are a superb teacher and I enjoy your videos all the way although I know some of the content already. But really now, his name is "Wien" not "Wein". Wien like the German name for Vienna. Btw, Wein in German means wine. Don't get confused :D
QM is amazing ! And my ultimate goal is to be a particle physicist.
DO IT!
Doc Schuster Yes i will!
Really great explanation!
But the thing that for me is not clear enough is why the black body "have" to radiate in all this higher frequencies so the Energy is infinite.
As far as I understand, given the temperature of the body within the box this implies some radiation at a given frequency with the corresponding intensity associated, why do you have to assume that all this high frequencies are also going to be radiated?
So ultraviolet catastrophe is a materials issue, so density of the object increases heat potential ie radiation energy?
What principle of classical physics compelled Rayleigh and Jeans to assume equipartition of energy across all frequencies?
How can color depend on temp? This means the violet letters should have a higher temperature than lets say the red letters. But this can’t be true. What’s the reasoning here? Why are the red letters produced by the sharpie not as hot as let’s say a stove top coils that are glowing red? What is the difference here? Thanks
Just for fun...I would like to share something that your reflective box (@ ~ 2:30) reminded me of.....
I remember--sometime back in the '80's--I had an old Metrologic He-Ne laser I used for making transmission holograms. I was at a large house that had huge mirrors on the wall--well, we (kids then) lit a smoke bomb in the room (the best way to see the Si-Fi - looking red beam bounce all over the room--I think the room would have filled completely with solid red formed from beams if it weren't for objects in the area--You could move one object and get much, much more or less reflections all over the place.
It made me wonder: What would happen if you could shine the beam in through a -tiny- opening of a room that was " 100% " mirrored inside!! Walls, floor, ceiling, etc. Anyone have any thoughts--I even considered trying it-- but too many little completions. AND...this was a
Nice!
This was fun. Thanks for posting.
I really really really love your channel
You pose me an example problem, and I'll see what I can do!
What If we give a straight ray of light directly into the black hole?
Your videos are awesome.
You're really nice! Thanks!
Awesome way of teaching .
Thank you so much for your effort, it really helped (y)
Well you can't really get wavelengths smaller than the planck's length and therefore the ultra-violet catastrophe wouldn't occur as such. Does this logic work? 9:09
pencilpen786 Sounds great as an ultimate prevention. They certainly didn't believe in a Planck length at the time that the catastrophe reared its head. The classical prediction still blows up at WAY larger lengths, before the PL becomes a concern.
Cool. Thanks for that
with the intensity you mean the glow , and with the frequency you sir mean the number of electromagnetic waves emitted ?
You seem to have the correct idea. Electromagnetic wave of a particular frequency can be emitted at different intensities. Intensity is like power. Think of it as number of photons per second. The greater the number of photons per second, the greater the intensity.
Frequency - we may look at the general definition : number of cycles per second. The greater the frequency of an electromagnetic wave, the greater the energy of its photon. (E = hf)
Intensity is the number of EM waves emitted (per second)
Frequency is the energy of the photon given by E=hf or E=hc/wavelength (since c=wavelength x f)
How did they measure wavelength of light in those days and these days
If only I had you as my teacher...
in the classical law , why there have to be all the frequencies?
Such a nice video.
I like the way you speak
Thanks! I like the way you dance.
Comnea Bogdan yes, its almost perfectly understandable.
you are inspirational doc. im a phscyisist too
Dilrukshi Perera YES!!! Uncover the secrets of the universe!
Thanks for the cool video!
Ps: He is called Wien (like the city "Vienna" in German) and not Wein (meaning "wine" in German) :D
Lastly, LOTS of confusion comes from thinking about the total conservation of energy regarding the energy you're putting INTO the black body vs what's being emitted. In other words, regardless of quantization, what happens when you increase the amt of energy put INTO the black body, in terms of what's emitted? You're saying the black body would emit MORE energy from higher frequencies, thus T max would move on your graph to the right, and your temperature of the black body would go higher. essentially, you're curve, as energy is added to the system, would grow (total intensity or power out) in the upward and rightwards directions, sorta like filling up quantum cups at the different frequencies and building on top of the cups like a pyramid. (if you think of each different-sized cup as a frequency) So your graph would look like a ballon that's being squeezed from one side only, but also growing (as temperature rises).
Perhaps the biggest mistake in all these Planck videos is no one describes the full system, from adding the energy to the black body and then measuring the black body's radiation out. gosintas and gosouttas. This is how to relate to the rest of us, instead of just skipping this. Planck himself would've understood the WHOLE system, not the short-cut version always presented in lectures. This is why traditional teaching methods always suck. You've simply gotta make this stuff so Kindergartner's can understand it.
Snow is a near-perfect blackbody. True. I lover physics.
Good job
can you do a Smin Rmax problem for me?
5:57 that is a popular device in 2020
Do you teach astrophysics concepts as well?
+Amee Bird Not much, but I'm taking requests at this time, Amee!
+Doc Schuster Well, at the moment in Quantum Physics, we are discussing Magnetic Dipole Moments, Spin, and Transition Rates. Then, in Astrophysics, we pretty much apply what we learn in Quantum Physics to astronomy.
squuur
hahahahsh at first I didn't get it but then came the formulas 😆
The emission of a continuous spectrum of EM wave actually contradicts Quantum Mechanics and the photoelectric effect proposed by Einstein. See, if Einstein's explanation of photoelectric effect is correct, some of the photons generated by the black body (say a good piece of metal) should be able to excite an electron inside the metal so that it will leave the atom!! But electrons do NOT come out of a piece of heated metal no matter how high its temperature is! That is if the state of an electron only depends on the frequency of the light that hits it, then some photons from the continuous spectrum of EM wave emitted by a heated piece of metal should have a sufficiently high frequency and hence sufficiently high energy to knock some electrons out of the metal.
did you say speed of light squirreled?
If only animals all had their own mathematical operations! "Find the manatee of 17, class." "If y = 2x, what is groundhog(y)?" I think I have a book idea I can begin with my biologist wife!
How frequency gets higher???
Is this Ryan Reynold teaching us physics stuff?
all over the place, yet somehow you hit some very relevant points about Intensity and the black box. HOWEVER, you need to really firm up if the black body radiation is coming from the outside SURFACE of the black body, or the slit of the black body. I find this to be VERY unclear in all talks about black bodies, somehow Physics teachers don't like to be very precise when describing a physical system, which is wierd, bc I could understand MATH dudes doing blurry experimental descriptions, but you'd think PHYSICS geeks would REALLY focus heavily on EXACT descriptions of physical systems. So, in short, slit emission or surface emission?
slit/hole emission
"this even looks bigger then infinity " i am done. 7:51
Wait but the fact that his armpit temperature is 30 degrees.... He got a huge fever...
Great video! Now I just need to know whether 'Planck' is actually pronounced "plonk" or if this is just another example of you being silly :)
The way he speaks reminds me of Dory from Finding Nemo at times.
u say I equal 2 f^2 k T / c^2 but i find in sewary is 2 π c k T/ wave length^4 what is the right of one og this two laws
Both. It's based on c = f(lambda).
how about molted gold.
Why is there discrepancy b/w experimental and calculated ones?
You might think so, but I'm pretty cool. Heh. Let's take a poll - how hot is your armpit?
THIS is why I like the internet. My local students always look at me funny when I ask that question.
"Morley"
en.m.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment
other questions not answered in your video: you don't define Intensity in terms the layman can understand. Show us the difference (in real world example) of high intensity vs low intensity (for the same temperature, and then for different temperatures). And then also you need to describe things at the quantum level, and by that I mean the vibrations of the atoms/molecules in the black body which are causing the photon emissions. If you create some simple examples, such as a two-atom black body, you can probably make your description palatable to the avg human.
It would be cool if soups glow red.
I like the intonation of ur voice sir hihi
That Kelvin sucker was tryna be oversmart
Soup is dangerous?
Look up Pierre-Marie Robitaille's papers and presentations (Sky Scholar YT). He proved Kirchoff's law is invalid along the way to setting the world record with the first 8T NMRI. He set the bar. Everyone else plays catch up.
Kelvin did a lot of good stuff in lots of areas of mathematical physics (he calculated ship wake angles as one curious example) but he waded into some muddy waters sometimes. I think he rejected Darwinian evolution because his calculations showed the earth couldn't be billions of years old. Of course he didn't have a very balanced judgement here and with hindsight geology and fossil and biology evidence is also part of the physical universe and needed to be considered on its merits too. Physicists were getting lost until they found the radioactivity and nuclear physics and qm and stuff.
No one found the medium where light travels.
Should your armpit be at least 36 celsius !?
he was right, blackbody its a wrong model, there are interaction of obscillators and dinamics
Hope u answer me 😂😂🙂my teacher told me that the black hole take all of the radiation 100%and let it out 100% in the same time and in my book say that it takes the radiation perfectly and let it out perfectly!😂😂😂my english not good but try to understand me😂😂❤️
Wow!
Ughh.. Why do I even attend college?
You think you're black?... Rachel Dolezal much?... Haha just kidding. I appreciate your videos!
+Maddix Just black on the inside. Thanks for watching!
Lol lord Kelvin plz 😂
BLAAAAAAAAAAAAAAKEEEEEEEEEEEEEEEEEEE
Einstein ratio'd Lord Kelvin, lmao
sqwer
please StOPP
You should prepare your videos better. What a mess!