Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: bmorrow492 on 25/06/2009 02:55:04

Title: Photon quantum entanglement across time?
Post by: bmorrow492 on 25/06/2009 02:55:04
On page 52 of the September 2008 Discovery magazine, I read the following:

"There was a paper published in Science this February, and what it showed was that if you do an experiment with a photon, put it in the apparatus, that what you do right now actually changes an event that already occurred in the past."

This is the only mention I have read of quantum entanglement across time (if that is indeed what this means).  Can someone enlighten me on the subject or give a web site discussing the topic?
Title: Photon quantum entanglement across time?
Post by: lyner on 25/06/2009 14:18:27
I think it wouldn't actually be in the past. It would take time for you to find out that it had happened because the information would have to travel to you at light speed or less. When you saw it, it would have already happened.
Title: Photon quantum entanglement across time?
Post by: Vern on 25/06/2009 14:23:00
The problem I see is that the paper published the conclusion reached and not the actual results. I have never seen actual results that demand that the observed entanglement of particles do not happen at the time of creation and not at the time of observation.