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  4. Can you slow down light?
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Can you slow down light?

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Offline yor_on

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Can you slow down light?
« Reply #20 on: 18/09/2010 12:36:20 »
Now, there is another way to look at bouncing :)

Think of a mirror, and the photons 'bouncing' there. Somewhere I read that bouncing the photons gives them twice the impulse/pressure on whatever they 'hit' than if it just absorbed them. And while thinking of sending photons into a ultra-cold condensate. Do photons have a 'vibration'? If you think it has, what happens with that in deep space, does it stop 'vibrating'?

As I assume this vibration to be an equivalence to its energy that is :)
If I'm wrong there, and vibrations/motion have no relevance to a photons energy, then what have?
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Offline yor_on

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Can you slow down light?
« Reply #21 on: 18/09/2010 12:47:56 »
I mean, we know that a photon can contain different amounts of energy, as proved by the way 'black body radiation' works, right? And as I assume temperature to be an expression of energy too, I take the liberty of assuming this relation to go all the way here ( for the question :)

You might say that the vibration here is their 'motion' in SpaceTime, but how can photons then be of different energies, as they all seem 'identical' in all other ways, except in their polarization/spin possibly?

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Offline yor_on

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Can you slow down light?
« Reply #22 on: 18/09/2010 13:18:22 »
Normally a definition of the photons energy is made from its 'frequency' or inversely its wavelength.- Look here -.. But when looking at one single photon, how do you define a frequency to that? I don't expect it possible, other than as a 'vibration' or like a defect in the fabric of SpaceTime. Also, 'virtual photons' have no such restrictions. So, how do they do it?
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Offline CPT ArkAngel

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Can you slow down light?
« Reply #23 on: 19/09/2010 06:36:33 »
photons are defined by their energy...

Quote from: yor_on on 18/09/2010 13:18:22
Normally a definition of the photons energy is made from its 'frequency' or inversely its wavelength.- Look here -.. But when looking at one single photon, how do you define a frequency to that? I don't expect it possible, other than as a 'vibration' or like a defect in the fabric of SpaceTime. Also, 'virtual photons' have no such restrictions. So, how do they do it?
« Last Edit: 19/09/2010 07:52:46 by CPT ArkAngel »
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Offline Geezer

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Can you slow down light?
« Reply #24 on: 19/09/2010 06:46:36 »
Quote from: CPT ArkAngel on 19/09/2010 06:36:33
it is defined by its energy...

Er, what is defined by what exactly?
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Offline kenhikage (OP)

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Can you slow down light?
« Reply #25 on: 05/10/2010 03:33:29 »
Quote from: CPT ArkAngel on 16/09/2010 21:26:50
Quote from: kenhikage on 16/09/2010 09:44:45
Quote
Photons don't bounce on atoms, they are absorbed and another photon is emitted... This takes some times so you could think it slows down the photon but it is not the same one...
Interesting. What causes it to emit, just having too much energy to store it all? If so, it seems strange that it would accept more energy and kick out old, rather than simply letting the original photon pass by.

Atoms exist only in specific quantum energy level states. Each state is associated with electrons energy levels. An atom can be excited to another higher energy quantum state if it is hit by a photon of the same energy as the difference of the 2 quantum states. It results in a higher quantum vibration state of an electron revolving around the atom nucleus. The atom will then emit another photon in order to return to a more stable quantum state (probably of the same energy as the prior photon).

Late late reply, sorry. That makes sense. What determines the energy requirements of a quantum state?
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Offline kenhikage (OP)

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Can you slow down light?
« Reply #26 on: 05/10/2010 03:50:41 »
How Do You Catch An Atom And Pin It Down? [:o]
Could one do this to light using, say, leptons? Something else?
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Offline lil_muz

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Can you slow down light?
« Reply #27 on: 06/10/2010 06:08:33 »
yes, light slow down in denser transparent medium. such as water, glass, and prism..
newbielink:http://en.wikipedia.org/wiki/Speed_of_light [nonactive]
« Last Edit: 06/10/2010 06:13:17 by lil_muz »
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Offline kenhikage (OP)

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Can you slow down light?
« Reply #28 on: 08/10/2010 11:57:27 »
Quote from: lil_muz on 06/10/2010 06:08:33
yes, light slow down in denser transparent medium. such as water, glass, and prism..
http://en.wikipedia.org/wiki/Speed_of_light
Please see the first post on this topic.
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Offline syhprum

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Can you slow down light?
« Reply #29 on: 08/10/2010 15:59:42 »
I understand that the subliminal speed of light in a material of refractive index of more than 1 is commonly attributed to its absorbsion and re emission by atoms.
Is this not now considered rather over simplistic what other explanations are offered.
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