B Can a light beam stop in air?

is it possible, i mean can we hold it at a certain distance we want ?
 

BvU

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Hello Ramazan, :welcome:

What kind of air are you thinking of ?
 
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 doesnt matter. Light can travel in both mediums, right?
 

BvU

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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.
 
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 isnt really possible ? what do you relly on ? can you show me any proof of it..thank you btw
 

Nugatory

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How can you say that isnt 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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How can you say that isnt 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
 

Mister T

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How can you say that isnt 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.
 

ZapperZ

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i consider it inside of the atmosphere, on earth. But in vacuum i guess it doesnt 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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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.
 
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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.
 

jbriggs444

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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.
 

BvU

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@Ramazan Duzgun : does any of this help you ? (other than showing multi-interpretability of your original question :wink: )
 

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