View Single Post
May25-05, 09:25 AM
P: 15
That's not quite right.

Bell showed that communication does travel faster than light, but we just can't use that random-to-random communication to piggyback any information on.

Here's another URL to the same paper - See Fig 6:

But in Mandel's now classically quoted experiment, blocking Idler beam 1 does cause a noticeable change elsewhere at the Signal detector where the interference pattern disappears.

What is the time gap between blocking the idler path, and noticing the signal interference pattern disappearing.

Is it

1] Instantaneous (like Bohm's pilot wave) - but this has been proven impossible by Eberhard in similar but not identical cases

2] The direct straight line distance between the cause and effect. Cause is the place where the idler beam is blocked, and effect is the signal beam detector (A & B in my previous post)

3] The actual distance travelled by the light beams between the cause and effect (which is longer than 2] as the light beams take a tortuous route in the experiment - this is the sum of two paths, the idler beam from downconverter to block, and the signal beam from downconverter to detector).

or 4] The distance between where the two idler beams would have first met each other on the one hand, and the effect on the other. This is similar to 3], but with an addition - ie this is the sum of two paths, the idler beam from downconverter to the point it would have first met the other idler beam, and the signal beam from downconverter to detector. After all, according to Mandel, it is the idler beams meeting each other and destroying latent information which allows the interference pattern to occur at the signal detector. (missed this one out the first time).

We can gain (can we not) significant understanding of the 'spooky' quantum effect by determining if the answer is 2), 3) or 4).

Can anyone help me understand which it is.