Entanglement Between Photons that have Never Coexisted

In summary,The experimental setup demonstrated that photons 1 and 4 violate a Bell Inequality, demonstrating their entanglement.
  • #36
Meselwulf said:
Do not presume sir, to think you know what QM is... in totality. QM has many hidden truths which far outweigh what we ''think'' we so audaciously believe we know... there could be a superluminal transaction... as I said... the Transactional Interpretation, a real working theory, may answer it all.

I probably missed the part where I stated that I know what QM is. :biggrin:

And you apparently missed the part where I chose NOT to argue against the Transactional Interpretation, which I have no beef with at all. In fact, I would expect anyone familiar with it to embrace the paper which started this thread (as providing experimental support for it).

And I definitely missed any connection between Sarfatti and the Transactional Interpretation, which has nothing whatsoever to do with him. That is usually attributed to Cramer.
 
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  • #37
Meselwulf said:
If you don't disagree with over another, then explain one fact to me... why the idea of a superluminal transfer of information... is... forbidden enough for you to threaten me with a moderator action?

Simple: there are no accepted interpretations supporting superluminal signaling. Asserting otherwise runs afoul of forum rules. TQM is an accepted interpretation precisely because it is functionally equivalent to sQM.
 
  • #38
Meselwulf said:
Well, ironic, because QM is not fully understood so what we have to deal with is interpretations, not absolutions.

I quite agree. But within very strict bounds. Those have been best framed by Bell.
 
  • #39
DrChinese said:
I probably missed the part where I stated that I know what QM is. :biggrin:

And you apparently missed the part where I chose NOT to argue against the Transactional Interpretation, which I have no beef with at all.

Very well.


... ;)
 
  • #40
DrChinese said:
I quite agree. But within very strict bounds. Those have been best framed by Bell.

ty... however... Since the remarkable man known as Bell... physics has known a great much more things...
 
  • #41
DrChinese said:
Simple: there are no accepted interpretations supporting superluminal signaling. Asserting otherwise runs afoul of forum rules.

Small correction: de Broglie-Bohm theory, which is an interpretation of sQM in the case of quantum equlibrium, allows superluminal signaling outside this equilibrium.
 
  • #42
good reference/paper DrChinese.

DrChinese said:
This means that photon 4 is now entangled with photon 1, even though photon 1 no longer exists!

Experimental realization of that setup shows that photons 1 and 4 violate a Bell Inequality, demonstrating their entanglement.

how is the Bell Inequality shown (experimentally) when photons 1 and 4 don't even exist?

how is an (Bell's) experiment performed on particles that no longer exist?
 
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  • #43
San K said:
good reference/paper DrChinese.



how is the Bell Inequality shown (experimentally) when photons 1 and 4 don't even exist?

how is an (Bell's) experiment performed on particles that no longer exist?

They are measured as per usual and then a post-selection process is executed. A difficulty is to synchonize the photon arrival times so that the correct 4 are considered (since a coincidence time window must be created).

"We chose the delay length
to be the time between eight consecutive laser pulses, in
order not to lose signal due to the dead-time of the single-
photon detectors (Perkin Elmer SPCM-AQ4C), and to
provide enough time for the measurement of the first pho-
ton before the second pair is created. The delayed photon
of the first pair and the non-delayed photon of the second
pair are projected onto a Bell state by combining them
at the projecting polarizing beam-splitter (PBS) (see Fig.
2) [5]. We post-select the cases where each photon exits
this PBS at a different port. We ensure that the pho-
tons are indistinguishable, i.e., no information is available
as to whether both were transmitted or both were re-
flected."
 
  • #44
DrChinese said:
A future context affects the past (since the decision to entangle 1 and 4 is made after 4 is detected) !

http://arxiv.org/abs/1209.4191

Not sure about "Future context effecting the past" -

because (maybe)

The post selection criteria/process is such that is seems that way...but its not so.

Namely - only those photons get post selected that make it seem as if...future is effecting the past.

This is the same argument as used in Delayed choice quantum eraser.

In two words... its a "filtering trick"
 
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  • #45
San K said:
Not sure about "Future context effecting the past" -

because (maybe)

The post selection criteria/process is such that is seems that way...but its not so.

Namely - only those photons get post selected that make it seem as if...future is effecting the past.

This is the same argument as used in Delayed choice quantum eraser.

In two words... its a "filtering trick"

The experiment agrees with quantum theory on this possibility, so are you claiming quantum theory is wrong? Or, do you believe such experiments *are* possible, but this experiment simply has flaws?
 
  • #46
RUTA said:
The experiment agrees with quantum theory on this possibility, so are you claiming quantum theory is wrong? Or, do you believe such experiments *are* possible, but this experiment simply has flaws?

FYI: You replied to an almost one year old post :wink: (not that it matters to me, but I just wanted to let you know).
 
  • #47
DennisN said:
FYI: You replied to an almost one year old post :wink: (not that it matters to me, but I just wanted to let you know).

The post that I responded to just arrived in my email this morning. I noticed it had a date from last Oct, but it said "Edited" so I guessed that it was changed last night, since I was only this morning notified.
 
  • #48
There was another new post that got deleted.
I think this thread is done.
 

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