Back to time

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rajesh bhowmick
Posts: 1
Joined: Sat Oct 14, 2006 9:43 am

Back to time

Postby rajesh bhowmick » Sat Oct 14, 2006 9:59 am

Can electromagnetic waves be sent back to time?

Posts: 14
Joined: Sat Oct 14, 2006 1:47 pm

Postby cazcazcaz » Sat Oct 14, 2006 1:58 pm

perhaps, but its not the way you mean. a photon is it's own anti-particle so a feynman diagram shows it as a wavy line with no arrow, that is it is traveling both directions in time. However, if you look at it as traveling back in time the particles become their antis...
for example

p ~~(photon)~~ !e

under t symmitry becomes

e ~~(photon)~~ !p

but the entropy only increaces in one direction "the arrow in time"

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