[Bored chemist]

Depends on what?

If you don't understand what factors are likely to affect heat transfer, you just are not bright enough to do science.
Try your hand at something else.
If, on the other hand, you can recognise what factors are likely to affect it, stop trolling.

Both options suggest you should stop posting.

[hamdani yusuf (OP)]

Depends on what?

If you don't understand what factors are likely to affect heat transfer, you just are not bright enough to do science.
Try your hand at something else.
If, on the other hand, you can recognise what factors are likely to affect it, stop trolling.

Both options suggest you should stop posting.

If you don't want to answer questions,

you should stop posting.

[hamdani yusuf (OP)]

the concept of temperature

Teaching thermal physics,
is as easy as a song:
You think you make it simpler,
When you make it slightly wrong!

---Mark Zemansky

[hamdani yusuf (OP)]

Magnifying The World's Brightest Flashlight (200,000 Lumens)

This video can give some reality checks for our current understanding of temperature.

[Bored chemist]

Magnifying The World's Brightest Flashlight (200,000 Lumens)

This video can give some reality checks for our current understanding of temperature.

Are you using the "Royal we" ?

BTW, this still applies.

So...  you do understand that the heating effect you from from focussing sunlight is nothing to do with the "laser" cooling effect, don't you?

You said that photon from laser is indistinguishable from other sources, wich make them equally good for cooling. The video shows that they are different.   

It doesn't show that they are different in a relevant way, does it?

You could still use a non-laser light source for cooling. (I didn't say they were "good" for it, did I?. I said they were not good.You made that up. Why did you do that?)

The point I was making was that laser cooling has nothing to do with the negative electronic temperature in a laser.
Do you understand that?

Incidentally, the video is wrong. The "explanation" about lenses is irrelevant if you use non-imaging optics.

[alancalverd]

The phrase "magnifying 200,000 lumens" is, I think, meaningless, so I won't bother to watch the video.

[hamdani yusuf (OP)]

BTW, this still applies.

I asked Gemini. Is there a known alternative light source for cooling other than laser?

No Practical Alternative to Lasers for Cooling
As of now, there is no known practical alternative light source to lasers for cooling atoms or molecules.
The unique properties of lasers, such as high intensity, monochromaticity, coherence, and directionality, are essential for the precise control required in laser cooling. These properties are not readily achievable with other light sources.
While theoretical explorations and experimental attempts continue, lasers remain the dominant and most effective tool for this purpose.

[alancalverd]

Which is a long form of what BC wrote.

[Bored chemist]

BTW, this still applies.

I asked Gemini. Is there a known alternative light source for cooling other than laser?

No Practical Alternative to Lasers for Cooling
As of now, there is no known practical alternative light source to lasers for cooling atoms or molecules.
The unique properties of lasers, such as high intensity, monochromaticity, coherence, and directionality, are essential for the precise control required in laser cooling. These properties are not readily achievable with other light sources.
While theoretical explorations and experimental attempts continue, lasers remain the dominant and most effective tool for this purpose.

So, the chat bot understands the  word "practical", but you don't.
An interesting  experiment in its way, with  an unsurprising conclusion.


Today, nobody in their right mind would try to make (visible light) holograms without using a laser.
But the guy who first made them did so- because there were no lasers.
The use of a filtered mercury lamp would be considered impractical today.

[hamdani yusuf (OP)]

You could still use a non-laser light source for cooling. (I didn't say they were "good" for it, did I?. I said they were not good.You made that up. Why did you do that?)

Your claim above contradicts Gemini. You sound like non-laser cooling were already widely known, despite their inefficiency.

[hamdani yusuf (OP)]

The phrase "magnifying 200,000 lumens" is, I think, meaningless, so I won't bother to watch the video.

What should be changed to make it more meaningful?

[hamdani yusuf (OP)]

The Long Answer - Everything You Ever Wanted To Know About Entropy

This is the second, and longer, "solution" video to my "new brainteaser" video about compressing air, losing ALL the energy used to compress it, and still having compressed air that can be used to run my pneumatic tools.

I want to thank Dr. Michelsen for his generosity.  He also has an excellent document he's posted on-line that you can see here:
"Statistical Mechanifesto or Funky Statistical Mechanics Concepts"
https://elmichelsen.physics.ucsd.edu/...

If you search the document for "brain teaser" you can see what he's written about this problem.

I encourage people to check it out.  If you want to forward the document, he requests that you forward the link rather than a copy of the document.  This is simply because he updates the document fairly regularly.

The unit of entropy reveals its connection between temperature and energy.

[hamdani yusuf (OP)]

The short version containing question and answer.

If you want to skip past all the nonsense (i.e. background), jump to 7:50.

[Bored chemist]

You could still use a non-laser light source for cooling. (I didn't say they were "good" for it, did I?. I said they were not good.You made that up. Why did you do that?)

Your claim above contradicts Gemini. You sound like non-laser cooling were already widely known, despite their inefficiency.

Bollocks.
What I said (and you quoted) was " I said they were not good".
And that statement is obviously correct.

It's not my fault if you didn't understand it. Everyone else seems to have known what I meant.

I did not suggest that anyone would be using them, given that lasers are good at it (and would be cheaper etc).

Gemini also said that the only practical option is a laser.
I was pointing out that an atom hit by a photon does not know if that photon came from a laser or a camp fire. So, in general, if you can do things with laser light, you can do them with light from other sources.

[Bored chemist]

The phrase "magnifying 200,000 lumens" is, I think, meaningless, so I won't bother to watch the video.

What should be changed to make it more meaningful?

They should have said "putting a lens in front of a torch".
Because that's what they did.

[Bored chemist]

Here's another, similar brain teaser.
I come home and I think my room (roughly 3m by 3m by 2.5 m ; I'm ignoring the volume of the fireplace) is too cold; it's only 10 C in here (283K) , so I switch on the heating- a 1 KW electric fire.
After 1000 seconds it is warm enough and I switch the heater off.

How much more energy is there in the air in the room?

(Making the usual (unrealistic) assumption that there's no energy loss to the walls and furniture or any gain from me being in there metabolising food.
We are  also assuming air is an ideal gas)

[hamdani yusuf (OP)]

" I said they were not good".

You need to be more specific. Do they work, but have weaknesses or unwanted side effects?
Or they only work in theory, with no real life demonstration?

[Bored chemist]

How to cool things using light other than laser?

The same way that you would do it using a laser, but using a different light source.
The fact that you ask this proves that you don't understand how laser cooling works.

" I said they were not good".

You need to be more specific. Do they work, but have weaknesses or unwanted side effects?
Or they only work in theory, with no real life demontration?

I do not need to be more specific. I pointed out that you could use a different light source.
That statement is true.

I wasn't attempting to describe the history of all uses of light.
I was  pointing out that you didn't understand laser cooling.

[hamdani yusuf (OP)]

They should have said "putting a lens in front of a torch".
Because that's what they did.

What's the consequences of "putting a lens in front of a torch"?
What's the intensity of the focused light? Is it the same as the unfocused one?

[hamdani yusuf (OP)]

How to cool things using light other than laser?

The same way that you would do it using a laser, but using a different light source.
The fact that you ask this proves that you don't understand how laser cooling works.

So, it only works in theory, then. Perhaps the theory that you believe hasn't completely describe physical reality yet.