How can light be slowed?

Tim13 · Sep 5, 2012

Has there been a previous thread that discusses how light can be slowed?

Thanks,
Tim13

Drakkith · Sep 5, 2012

Light can be slowed by making it pass through a physical medium such as glass, air, water, etc.

Chronos · Sep 6, 2012

Light can be slowed when emitted from a gravitational well. This is not effective for light passing by a gravitational well since it is blue shifted on the way in.

kbar1 · Sep 6, 2012

Chronos said: ↑

Light can be slowed when emitted from a gravitational well. This is not effective for light passing by a gravitational well since it is blue shifted on the way in.

You mean it gets red shifted? [en.wikipedia.org]. Speed is the same I believe, unless you run it through anything other than vacuum/air.

Brainiac2 · Sep 17, 2012

Shooting a lazer through super-cooled sodium atoms will slow the light to 34mph.

Tim13 · Sep 17, 2012

Brainiac2 said: ↑

Shooting a lazer through super-cooled sodium atoms will slow the light to 34mph.

If something can be slowed, then perhaps it may also be stopped? Perhaps the properties of light (its duality of wave and particle) are reactive based on environmental conditions? Is the particle nature more dominant in super cooled states and hence the light slows? Is the word "dominant" not the right choice?

Ferraridude · Sep 19, 2012

Tim13 said: ↑

If something can be slowed, then perhaps it may also be stopped? Perhaps the properties of light (its duality of wave and particle) are reactive based on environmental conditions? Is the particle nature more dominant in super cooled states and hence the light slows? Is the word "dominant" not the right choice?

You can think of light in the particle sense as an important man walking in a room. If he is just walking through an empty room, he is not really affected, as in, he is not bouncing around. If he just made an important speech, he will be shaking peoples hands a lot, just bouncing around, always going the speed of light, just in a zig-zag path. I don't think light will ever look like it is going completely at 0 speed relative to anyone else.

mfb · Sep 20, 2012

It is possible to "stop" light - but what really happens is that those photons are converted to other excitations, and back to photons afterwards.

Brainiac2 · Sep 21, 2012

Tim13 said: ↑

If something can be slowed, then perhaps it may also be stopped? Perhaps the properties of light (its duality of wave and particle) are reactive based on environmental conditions? Is the particle nature more dominant in super cooled states and hence the light slows? Is the word "dominant" not the right choice?

When the lazer is suddenly turned off the light freezes for a fraction of a second within the gas only to resume after the lazer is turned back on .

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How can light be slowed?

Tim13

Drakkith

Staff: Mentor

Chronos

kbar1

Brainiac2

Tim13

Ferraridude

mfb

Staff: Mentor

Brainiac2

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