Talk:Slow light

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[edit] request for expansion

I'd like to see this article expanded with some information about stopping light. From what I've read on various websites this is done with Bose–Einstein condensate. I've found some sources about it [1], but I hardly know anything about the subject so I'm not too eager on adding it myself.

Also some (past) records on minimum speed achieved would be nice to have added in. - Dammit 17:57, 7 May 2006 (UTC)

[2] I have a link here Mindule 08:36, 31 December 2006 (UTC)


acording to the anu pesopls they have stopted the longest (by a factor of 500 over the nearest competitor) using a laser to induce an opace material to become clear then after the light is in it to turn of the laser.. theoretically stoping it indefinatly ill get to referenceing it and stuff laterShinigami Josh 12:55, 28 May 2007 (UTC)

[edit] cut Unknown Worlds reference.

With some dithering, I deleted this paragraph: "Slow glass also appears in Unknown Worlds Of Science Fiction comics (1975). In these stories, the glass originates in the future, and its ability to show "...scenes from various locations in time, space and other dimensions..." is used as a framing device for the comic's stories. It's use was directly inspired by Bob Shaw's story.[3]". The reason I deleted it is that, if the piece of glass shows other locations in "space and other dimensions," it clearly isn't slow glass, but something quite different. (also, I note that the link is non-existent). Geoffrey.landis (talk) 15:40, 20 November 2007 (UTC)

[edit] Holograms

Am I understanding this right? It seems to me that if one could stop light in midair then it would be possible to create free floating holograms? someone tell me if i'm wrong 71.176.133.186 (talk) 20:39, 9 January 2008 (UTC)

You have to be able to see the hologram, so you can't just stop light. so then you start up the light again, but then its gone in a nanosecond. However if you can record where the light wave patterns are permanently you can then see them continuously. Graeme Bartlett (talk) 01:06, 10 January 2008 (UTC)

[edit] Absorption

I'm no quantum physicist, but it seems the explanation on this page of how light is slowed down physically is called incorrect on Speed of light

This page says: "In the case of absorption and re-emission, there is a finite amount of time for a material to absorb and re-emit a photon and this lag time will cause an effective "slowing" of the observed photon speed. Between absorptions and re-emissions, however, the photon is traveling at c."

while Speed of light#Interaction with transparent materials says: "It is sometimes claimed that light is slowed on its passage through a block of media by being absorbed and re-emitted by the atoms, only traveling at full speed through the vacuum between atoms. This explanation is incorrect and runs into problems if you try to use it to explain the details of refraction beyond the simple slowing of the signal."

Which is right? --71.105.111.86 (talk) 03:22, 5 February 2008 (UTC)

[edit] Military uses

I have removed this paragraph:

In military use, stopping or considerably slowing down light could be used to camouflage vehicles. If the light were stopped, the vehicle would be invisible and would only appear as a blind spot in the eye of an observer. If the light were slowed down, the vehicle would reflect the light slower that the light reflecting off of the vehicle's surroundings, causing observers to see only a distortion in the air.

It sounds quite unbelievable to me, but it is also unsourced, and I can not even imagine a possible source for something like this. Also if light were stopped, the vehicle would appear black. --CyHawk (talk) 00:19, 9 March 2008 (UTC)