Stopping Light in Air: Myth or Reality?

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Discussion Overview

The discussion revolves around the possibility of "stopping" light in air, exploring whether it can be held at a certain distance without absorption or obstruction. Participants consider various contexts, including atmospheric conditions and the behavior of light in different media, including gases.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants question if light can be held at a certain distance in air, suggesting that light can travel in both atmospheric and vacuum conditions.
  • Others argue that while light can scatter in air, it cannot be "stopped" without an absorbing medium intervening.
  • A participant references Maxwell's equations, stating they do not allow for a solution where light can remain stationary.
  • Another participant mentions the historical experiment by Lene Hau, who reportedly stopped light in sodium gas, raising questions about the definition of "air" in this context.
  • Some suggest that moving air at high speeds could theoretically allow light to be perceived as "stopped," but this is challenged by the limitations of physical laws.
  • There is a discussion about the speed of light in air being less than in a vacuum, with suggestions that manipulating air speed could affect light propagation.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility of stopping light in air, with no consensus reached. Some support the idea that light can be manipulated under certain conditions, while others maintain that it cannot be stopped without obstruction.

Contextual Notes

Participants reference various physical principles and historical experiments, but the discussion remains open-ended with unresolved assumptions about the nature of air and light interaction.

Who May Find This Useful

Individuals interested in optics, physics of light, and the theoretical implications of light behavior in different media may find this discussion relevant.

Ramazan Duzgun
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is it possible, i mean can we hold it at a certain distance we want ?
 
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Hello Ramazan, :welcome:

What kind of air are you thinking of ?
 
BvU said:
Hello Ramazan, :welcome:

What kind of air are you thinking of ?
i consider it inside of the atmosphere, on earth. But in vacuum i guess it doesn't matter. Light can travel in both mediums, right?
 
Yes, it definitely can.
My question was more if you consider fog and rain as air.

Light gets scattered by air molecules, but that's not really 'holding it at a certain distance'.

Actually stopping a ray of light isn't really possible without putting something in its way, to absorb it.
 
BvU said:
Yes, it definitely can.
My question was more if you consider fog and rain as air.

Light gets scattered by air molecules, but that's not really 'holding it at a certain distance'.

Actually stopping a ray of light isn't really possible without putting something in its way, to absorb it.
How can you say that isn't really possible ? what do you relly on ? can you show me any proof of it..thank you btw
 
Ramazan Duzgun said:
How can you say that isn't really possible ? what do you relly on ? can you show me any proof of it.
Light is an electromagnetic wave that behaves according to Maxwell's equations. These equations do not allow "standing still" as a solution.
(There is such a thing as a "standing wave", but that doesn;t sound like what you're thinking of).
 
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Ramazan Duzgun said:
How can you say that isn't really possible ? what do you relly on ? can you show me any proof of it..thank you btw
We receive light from galaxies billions of light years away, and the CMBR from even further.

We see it as long as there isn’t anything between us and the distant galaxy to absorb the light, as @BvU stated
 
Ramazan Duzgun said:
How can you say that isn't really possible ? what do you relly on ?

We're relying on the laws of physics, which are consistent with every observation made and every experiment ever performed.

If you were to ask this question in some place other than a physics forum you may get a different answer. But when you ask in a physics forum the answers are based on physics.
 
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Ramazan Duzgun said:
i consider it inside of the atmosphere, on earth. But in vacuum i guess it doesn't matter. Light can travel in both mediums, right?

What I want to know is if you are simply focusing on just regular, ordinary, atmospheric air, or do you also include ANY gas phase. Lene Hau has stopped light in Na gas back in... what, 2001? Not only that, she managed to hold it for some time, and then "released" it back!

Or did you miss this news?

Zz.
 
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  • #10
Ramazan Duzgun said:
is it possible, i mean can we hold it at a certain distance we want ?

Just let the air move with the corresponding speed in the opposite direction in this distance.
 
  • #11
DrStupid said:
Just let the air move with the corresponding speed in the opposite direction in this distance.
Well, the problem with that is that you can't get the air to move at the speed of light.
 
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  • #12
phinds said:
Well, the problem with that is that you can't get the air to move at the speed of light.
The speed of light in air is slightly less than c. So the possibility exists to get some "air" moving very close to c one way and shoot light through it in the opposite direction.

Easier yet, shine a flashlight at the wall and adopt a frame of reference in which the Earth is already moving near c. Bingo, light stopped in air.
 
  • #13
@Ramazan Duzgun : does any of this help you ? (other than showing multi-interpretability of your original question :wink: )
 

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