Re: Delayed choice experiment and interstellar signalling

On Mar 22, 3:53 pm, thro...@xxxxxxxxx (Wayne Throop) wrote:
: "Williamknowsbest" <William.M...@xxxxxxxxx>
: That URL won't load. Like I said I find your comments confusing and
: your URL is unreadable.

The URL reads fine for me, but I can see where it might not for
some newsreaders (there's no blank before the "http").
Here's that URL with the offending adjacent characters removed:

http://arxiv.org/PS_cache/quant-ph/pdf/9903/9903047.pdf

I tried it and it still won't load. The URL appears in the address
line but the screen stays blank. Adobe Acrobat loaded and it hung
up. I went away and got a cup of coffee. The window is still open,
and the activity indicator is still working, and the window is still
blank - both in the window itself and in the Adobe.

I do have Professional Edition if that means anything. I went back
and checked the Adobe program just now and it said "An I/O error has
occured. The file connection has timed out."

So there you go. So much for technology.

So, if you have another solution, I am willing to listen - I would
like to see what Sylvia is talking about.


Figure 2 shows exactly what Sylvia said it shows.

Ok - but that is not a description and my confusion still exists
since Sylvia clearly speaks about one photon interfering with
another. This doesn't make sense in the quantum world.


The entanglement occurs after the passage through the slit.

Alright. I'll take your word for it. But in the experiments I am
familiar with there is a quarter wave plate at the slits and the
entanglement occurs before the slit. That is, a short wave photon is
converted to two entangled longer wave photons. One of these is sent
to the double slit apparatus. The other is sent to be measured to
dtermine which slit it went through - or not.

However, it
occurs adjacent to either one or another of the slits. The fringe
detector can't tell which of the regions were used to do the entangling,
but the other, remote detector, can. If the remote detector discovers
which slit was used for the entanglement, the fringe doesn't appear, but
if it doesn't, the fringes do appear. Note that in the experiment as
set up, this is only apparent after you compare events from all the
detectors, because you don't know whether the delayed detectors figured
out the origin of the entanglement or not (the photons having passed
theough a half-silvered mirror, and you don't know under alfterwards
which events that occured for).


Since I don't have access to your image, I can't say anything
useful.

Whether the experiment can be set up to signal is unclear to me.
As it is described in the paper, it doesn't appear so, because you
can only detect these remarkable effects only by comparing all the
coincidence data from all the detectors.

Well lets look at another reference I can look up and discuss this
using a reference we both can look at

http://www.bottomlayer.com/bottom/basic_delayed_choice.htm


Note that IF the experiment can be set up to signal, I see nothing that
prevents constructing a reply that gets back before the signal is sent.
"Take that, causality!"

Yes, this was the whole point of Wheeler's thought experiment. The
double slit caused by the gravity lensing of a distant galaxy of a
photon that is emitted by even a MORE distant galaxy.

Check out the section, does our choice change the past? It does.

And this experimental result

http://www.sciencemag.org/cgi/content/abstract/315/5814/966?etoc

And because it does, then an experimental setup can signal along the
null surface the photon travels to communicate with the senders of the
photon.

Wayne Throop thro...@xxxxxxxxx http://sheol.org/throopw


.

Relevant Pages

  • One Photon Double Slit Reinterpretations
    ... In the double slit where you shoot an individual photon ... for several months that produce an interference pattern. ... the detector, our detectors are designed to trigger ...
    (sci.physics)
  • Re: To AC -- on electrons
    ... Not all waves require a medium in order to be able to ... fed through a double slit, one at a time, with a detector to keep ... so if a photon is detected going ...
    (talk.origins)
  • Re: atheists for freedom
    ... If we put a device on a slit which can detect a photon passing ... Placing a detector even in just one of the slits ... observer that made the lightpattern change. ...
    (talk.origins)
  • Re: Delayed choice experiment and interstellar signalling
    ... The entanglement occurs after the passage through the slit. ... but the other, remote detector, can. ... which slit was used for the entanglement, the fringe doesn't appear, but ...
    (sci.space.policy)
  • Re: How do you detech a photon passing through a slit?
    ... >> photon is fired at a wall with two slits in it with a photomultiplier ... >> slits to determine whether the photon passed through slit A or slit B ... >> loose any energy when it passes through this kind of detector? ...
    (sci.physics)