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View Full Version : Discussion: Researchers Stop Light in Its Tracks



Fraser
2003-Jul-08, 10:09 PM
SUMMARY: Researchers at Harvard University demonstrated that they can slow light and even completely stop it for several thousandths of a second. They built a chamber containing a cloud of sodium atoms cooled to almost absolute zero and then fired a light pulse into this cloud. The pulse slowed to a stop and even turned off – the researchers were able to revive it again by firing a laser into the cloud. Although this breakthrough happened a couple of years ago, and an upcoming special edition of Scientific American called “The Edge of Physics” will provide an update to the research.


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jkmccrann
2005-Dec-12, 06:45 PM
Relating to the other topic concerning the speed of gravity, I wonder if that means they can slow the speed of gravity down as well. Does anyone know if its been tried?

swansont
2005-Dec-12, 06:52 PM
Relating to the other topic concerning the speed of gravity, I wonder if that means they can slow the speed of gravity down as well. Does anyone know if its been tried?

The light was "stopped" by storing it in a specially prepared medium and then recreating it with the same coherent properties. It's not like you can confirm that they were the same photons. The photons, when in existence, moved at c.

jkmccrann
2005-Dec-12, 07:27 PM
The light was "stopped" by storing it in a specially prepared medium and then recreating it with the same coherent properties. It's not like you can confirm that they were the same photons. The photons, when in existence, moved at c.

Yes, fair point.

I guess things like that relate, to me at least, back to the possibility of teleportation. (Of inanimate objects I'm thinking of - I don't believe human teleportation is possible)