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Obviously into the atoms, that make the resonance cavity
Of course you are fully aware, that the the mass of the trapping box has billions times greater relativistic mass, than all the photons trapped in that box - so even your expactactions are fundamentally flawed
Nope. it's exactly opposite - momentum transfer during reflection of an EM wave increases it's wavelenght
And what exactly does it have to do with EM radiation trapped inside a cavity with decreasing volume?
Here:for example your claim is that:
"If the antenna is inside a reflecting cavity, however, its behavior changes
This is still true if the excited state has been perturbed by a cavity or, indeed, anything else.
The suppression of spontaneous emission at an optical frequency requires much smaller cavities. In 1986 one of us (Haroche), along with other physicists at Yale University, made a micron-wide structure by stacking two optically flat mirrors separated by extremely thin metallic spacers. The workers sent atoms through this passage, thereby preventing them from radiating for as long as 13 times the normal excited-state lifetime. Researchers at the University of Rome used similar micron-wide gaps to inhibit emission by excited dye molecules."
Quote from: CrazyScientist on 13/06/2021 00:52:12Obviously into the atoms, that make the resonance cavitySo, because the energy is absorbed by the walls, it isn't reflected.So it isn't a perfectly reflective wall- as specified.So your "explanation" only makes sense when you move the goal posts.
Quote from: CrazyScientist on 13/06/2021 00:52:12Of course you are fully aware, that the the mass of the trapping box has billions times greater relativistic mass, than all the photons trapped in that box - so even your expactactions are fundamentally flawedWell, yes and no.I'm the one who pointed out that a strictly perfect mirror needs to have infinite mass.But I also pointed out that, if you add enough photons the box collapses- regardless of the original mass of the box.The box was always pretty much doomed anyway- it was going to be right next to a BH.
Quote from: CrazyScientist on 13/06/2021 00:52:12Nope. it's exactly opposite - momentum transfer during reflection of an EM wave increases it's wavelenghtImagine doing that experiment, as shown in that diagram and filming it.Then imagine watching the film backwards.An electron heading towards the source of radiation (on the right of the picture) strikes the photon and , like hitting a ball with a bat, the photon is sent off towards the top left at a higher energy than it started with (and the electron is slowed down).That's the scenario we are talking about.The box wall is moving towards the photon and when it hits it, the energy of the photon is raised.It's fairly closely analogous to compressing a gas and getting an increase in temperature.
Quote from: CrazyScientist on 13/06/2021 00:52:12And what exactly does it have to do with EM radiation trapped inside a cavity with decreasing volume?It is the experiment where someone actually did bounce photons off a fast moving mirror and show that the photons' energy was raised.It experimentally demonstrates that your idea-
Quote from: CrazyScientist on 13/06/2021 00:52:12Nope. it's exactly opposite - momentum transfer during reflection of an EM wave increases it's wavelenghtis wrong if the mirror moves towards the source.The picture you show is the case where the photons cause the electron to move.If you hang a bat on a length of rope and throw a ball at it, the ball will transfer momentum to the bat and will bounce off more slowly than it started out.But that's not how it would work if you were deliberately squashing the box.
Quote from: CrazyScientist on 13/06/2021 00:52:12Here:for example your claim is that:It still isn't "my" claim.It's Kirchhoff's.And it's a direct consequence of the conservation of energy.Things that absorb will also emit.
Quote from: CrazyScientist on 13/06/2021 00:52:12"If the antenna is inside a reflecting cavity, however, its behavior changesYes.We know.I already pointed that out.Given that I wrote Quote from: Bored chemist on 12/06/2021 18:29:39This is still true if the excited state has been perturbed by a cavity or, indeed, anything else.the question is now, did you not read that, or not understand it?
Problem is, that when an EM wave hits a surface, it can interact with it only in two ways - the energy can be absorbed or it can be reflected. However even if the surface is 100% reflective, so the radiation isn't absorbed and turned into thermal energy, momentum transfer turns part of the energy carried by EM waves into kinetic energy of atoms that make the surface.
So, in real-life there's no way out of this situation,
However, there's another way to do it.You can imagine a nearly massless mirror.When a photon hits it, it will move and take some energy from the photon. But that means that, when another photon hits it on the other side, it will add energy to that photon.Overall, the sum of the energies will be conserved The wavelengths of the photons will be "scrambled" and will settle down to a black-body distribution.
(and yes - 100% reflective surfaces actually DO exist)
And this turns out to be incorrect,
Yes - but:1. It wasn't made in a cavity2. mirror was moving at relativistic velocitySo, this scenario has nothing to do with the one, which I presented in the first post of this thread... Sorry...
You know, that even 10yo kids know from physics and chemistry classes, that picturing photons as tiny balls/marbles moving through space, is completely incorrect
So, obviously this statement can't be applied to a scenario where EM radiation is emitted inside a cavity
Each system will reach an energetic equilibrium, as long as the input energy remains constant
I'm curious: what was your research field in the late 80s?
Quote from: CrazyScientist on 13/06/2021 20:11:39Problem is, that when an EM wave hits a surface, it can interact with it only in two ways - the energy can be absorbed or it can be reflected. However even if the surface is 100% reflective, so the radiation isn't absorbed and turned into thermal energy, momentum transfer turns part of the energy carried by EM waves into kinetic energy of atoms that make the surface.No.As I have pointed out a few times, and posted a link to the experimental verification , there are three things that can happen.If a photon moving left to right bounces off a mirror that is moving right to left then the photon gains energy (at the expanse of the mirror) and it leaves with a shorter wavelength than it starts.You need to stop ignoring that fact.
Quote from: CrazyScientist on 13/06/2021 20:11:39So, in real-life there's no way out of this situation, Yes there is. I pointed it out earlier in the thread.Quote from: Bored chemist on 07/06/2021 14:11:54However, there's another way to do it.You can imagine a nearly massless mirror.When a photon hits it, it will move and take some energy from the photon. But that means that, when another photon hits it on the other side, it will add energy to that photon.Overall, the sum of the energies will be conserved The wavelengths of the photons will be "scrambled" and will settle down to a black-body distribution.But you ignored it.
Quote from: CrazyScientist on 13/06/2021 20:11:39(and yes - 100% reflective surfaces actually DO exist)No, they do not. (Unless they are infinitely massive).Because, if a photon hits them, it transfers momentum to the mirror and (usually) loses energy.They are "perfect" in the sense that the number of photos bouncing off s the same as the number that hit, but they are not perfect in the sense of no energy transfer happening.
Quote from: CrazyScientist on 13/06/2021 20:11:39And this turns out to be incorrect, Proof by repeated assertion isn't going to work here.Particular not when you are doing the asserting, since it took you at least three goes to recognise Kirchhoff's law.[ edited to add that I was mistaken; CrazyScientist still hasn't recognised it. Maybe he will learn this time]
Quote from: CrazyScientist on 13/06/2021 20:27:06Yes - but:1. It wasn't made in a cavity2. mirror was moving at relativistic velocitySo, this scenario has nothing to do with the one, which I presented in the first post of this thread... Sorry...There's no way the photon can tell if there's another mirror moving away behind it, so there's no way that the second mirror in a cavity could make a difference.So your first objection is absurd.
Your second objection is absurd because, from the point of view of a photon, all mirrors are relativistic. They never hit them slowly.
Quote from: CrazyScientist on 13/06/2021 20:27:06You know, that even 10yo kids know from physics and chemistry classes, that picturing photons as tiny balls/marbles moving through space, is completely incorrectThe man who was previously trying to pretend that sound waves act the same was as light waves just broke the irony record.
It's not good enough to say that you don't like the analogy, because what I was relying on wasn't the analog, but the experimental fact that reflection from a moving mirror will shorten the wavelength if the mirror is traveling towards the source.
Quote from: CrazyScientist on 13/06/2021 20:27:06So, obviously this statement can't be applied to a scenario where EM radiation is emitted inside a cavityThe conservation of energy can be applied universally.Quote from: CrazyScientist on 13/06/2021 20:29:51Each system will reach an energetic equilibrium, as long as the input energy remains constantAre you muddling power an energy here?If you keep putting more net energy into a system, it does not reach equilibrium.
Ok, so let's now assume, that the battery is actually placed somewhere outside of the spherical cavity and is powering up a source of heat (thermal radiation), allowing it to maintain a constant temprature of 1000°C. Can you explain the mechanism, which in this case could possibly lead to creation of a BH out of the thermal radiation, which is constantly emitted by the source of heat inside the cavity?
MIRROR HAS TO MOVE AT RELATIVISTIC VELOCITY
IT DOESN'T WORK FOR A STANDING WAVE IN A CAVITY
IT HAS NOTHING TO DO WITH THE SCENARIO, WHICH I PROPOSED IN THE FIRST POST
Learn about the research of PHONONS
Sure - only it doesn't work in cavities...
I never said, that the system is powered by a source, that is increasing it's power output...
Yes - and my analogy of a buzzing speaker submerged in a sphere of water IS in 100% valid...
It's also interesting, how perfectly you managed to completely ignore this: Quote from: CrazyScientist on 12/06/2021 10:09:13Ok, so let's now assume, that the battery is actually placed somewhere outside of the spherical cavity and is powering up a source of heat (thermal radiation), allowing it to maintain a constant temprature of 1000°C. Can you explain the mechanism, which in this case could possibly lead to creation of a BH out of the thermal radiation, which is constantly emitted by the source of heat inside the cavity?Tell me, how you will solve that. I would love to hear some cool fairytale for good night
allowing it to maintain a constant temprature of 1000°C.
Quote from: CrazyScientist on 13/06/2021 21:57:34It's also interesting, how perfectly you managed to completely ignore this: Quote from: CrazyScientist on 12/06/2021 10:09:13Ok, so let's now assume, that the battery is actually placed somewhere outside of the spherical cavity and is powering up a source of heat (thermal radiation), allowing it to maintain a constant temprature of 1000°C. Can you explain the mechanism, which in this case could possibly lead to creation of a BH out of the thermal radiation, which is constantly emitted by the source of heat inside the cavity?Tell me, how you will solve that. I would love to hear some cool fairytale for good night It's not much of a story.This bitQuote from: CrazyScientist on 13/06/2021 21:57:34allowing it to maintain a constant temprature of 1000°C. implies that there's some system which measures the temperature of the sensor and adjusts the power in order to maintain 1000C - a thermostat.The hot body is enclosed by a perfect mirror. (I'm assuming it's in a vacuum too and is thus thermally insulated).Power is fed to it and that heats it.As it reaches 1000C the sensors of the thermostat throttle back the power from the battery.Once the body is at 1000 C the power fed to it drops to zero.The body stays hot because there's nowhere for the thermal energy to go.You can take the battery away now, if you like.
You can take the battery away now, if you like.
I see no sense in responding to your previous post,
Only then some part of the energy inside the cavity will get absorbed back by the source...
And you still seem to ignore the fact that , if a mirror hits a photon, momentum is transferred to the mirror.If the mirror was originally moving towards the photon, then the mirror will be slowed down by the momentum transfer.If the mirror is slowed down then it loses energy.And the conservation laws say that energy has to go somewhere.The only possibility is that it goes into the photon, and raises its energy.Where else?
If you don't agree, you'll have to prove that thermal radiation is somehow completely different from other types of EM radiation and only because of that, this particular scenario (thermal radiation) will have a different outcome.