Einstein's "Spooky Action At A Distance"

[ROM-DOS]

[compuworm]

Makes one wonder if spinning is necessary for gravity interactions.  Does black holes spin given their gravitational strength?  . 

[FallowEarth]

Way back in uni  , I remember learning about an experiment where a physicist (I can't remember who for the life of me and google is not helping) was able to shoot a single photon in a vacuum, and chart the path the photon took.  What the scientist discovered was that the photon never charted the same path twice, even in such a controlled environment.  His analysis led him to the conclusion that the photon was being affected by variables in the numerous other physical demensions of this world which we cannot perceive (common theories are that there are as many as 26 physical dimensions).  He also said that there are a number of layers or dimensions of time, where photons and various other particles are playing an effect (attraction and repulsion) on the single photon in our time dimension.

That was about the time when I dropped the course (j/j).

[compuworm]

Perhaps, but gravitational effects and position in time/space probabley had a say in the Photons path.

[FallowEarth]

You're probably right, but gravity is so vague, and it's relative, and there are too many bodies to factor in, and all bodies are in motion, and is there an ultimate gravitational centre to the universe?

[resopalrabotnick]

and how would one plot a photon's path? that would mean measuring it in some manner, which means either passing it through a detector, which alters its path, or bouncing something off it to measure it, in both cases invoking the heisenberg uncertainty principle that states you can not know the position and vector of something at the same time. you cannot 'see' the photon in the vacuum (not to mention there is no such thing as a perfect vacuum, regardless of what the orek and dyson salespeople tell you on tv) since it is a particle that while being a bit of 'light' would hae to emit photons to 'shine' and that seems highly unlikely. as for physically detecting it, that will of course change its path. too bad you don't remember the guy doing the experiment.

[compuworm]

I believe the term, "Relative", has been taken out of context for too long.  I think, of course you can correct me if I am wrong (I often am), but what is absolute and reliable despite the apparent confusions, illusions, and contradictions produced by RELATIVE motions or the actions of gravity; relatively only serves to remind us that the, "Observer", is an unavoidable a participant in the system under study. 

In fact, Einstein never said all things are relative.  In fact he thought, "Relativity", was a very bad name for his theory and thought about calling it the, "Invariance Theory", instead. 

4resopalrabotnick, I think the HUP is for subatomic particles, such as an electron, are photons even associated with having mass?

compuworm

[FallowEarth]

and how would one plot a photon's path? that would mean measuring it in some manner, which means either passing it through a detector, which alters its path, or bouncing something off it to measure it, in both cases invoking the heisenberg uncertainty principle that states you can not know the position and vector of something at the same time. you cannot 'see' the photon in the vacuum (not to mention there is no such thing as a perfect vacuum, regardless of what the orek and dyson salespeople tell you on tv) since it is a particle that while being a bit of 'light' would hae to emit photons to 'shine' and that seems highly unlikely. as for physically detecting it, that will of course change its path. too bad you don't remember the guy doing the experiment.

To the best of my memory, the photons were projected against a material that would change (colour I believe) when exposed to light, which through monitoring they were able to map each photon's path from the point of release.

[ROM-DOS]

[ROM-DOS]

Quantum entanglement on a chip

1/12/2006 11:31:26 PM, by Hannibal

A new article in Nature describes a breakthrough in generating photon pairs that are quantum entangled. Scientists from the University of Cambridge and Toshiba Research Europe Ltd. have come up with a way to fabricate a special, photon-generating quantum dot using techniques that are similar to current semiconductor manufacturing techniques. The quantum dot is shaped so that it can emit entangled pairs of photons on command. Such entangled photon pairs have potential applications ranging from quantum encryption to microscopic imaging.

The EET has some good coverage of the announcement, as does the New Scientist.

Scientists have been entangling photons for some time now, but existing techniques involve firing UV lasers into crystals, a process that produces regular photons along with entangled pairs. This new technique brings the generation of entangled pairs under a greater degree of user control. It also scales down the process by removing the laser apparatus and allowing entangled photons to be generated directly from a small semiconductor source, thereby paving the way for "entanglement chips" that could be used in a variety of applications.

Quantum entanglement and encryption

Quantum entanglement is a phenomenon that Einstein famously dubbed "spooky action at a distance." In short, an entangled pair of photons have quantum properties that are linked to each other. If one photon's spin is up, the other must be down. So if you generate an entangled pair of photons and then separate them by any distance

[Shug7272]

Quantum entanglement on a chip

1/12/2006 11:31:26 PM, by Hannibal

A new article in Nature describes a breakthrough in generating photon pairs that are quantum entangled. Scientists from the University of Cambridge and Toshiba Research Europe Ltd. have come up with a way to fabricate a special, photon-generating quantum dot using techniques that are similar to current semiconductor manufacturing techniques. The quantum dot is shaped so that it can emit entangled pairs of photons on command. Such entangled photon pairs have potential applications ranging from quantum encryption to microscopic imaging.

The EET has some good coverage of the announcement, as does the New Scientist.

Scientists have been entangling photons for some time now, but existing techniques involve firing UV lasers into crystals, a process that produces regular photons along with entangled pairs. This new technique brings the generation of entangled pairs under a greater degree of user control. It also scales down the process by removing the laser apparatus and allowing entangled photons to be generated directly from a small semiconductor source, thereby paving the way for "entanglement chips" that could be used in a variety of applications.

Quantum entanglement and encryption

Quantum entanglement is a phenomenon that Einstein famously dubbed "spooky action at a distance." In short, an entangled pair of photons have quantum properties that are linked to each other. If one photon's spin is up, the other must be down. So if you generate an entangled pair of photons and then separate them by any distance