Quantum entangled-photon Chinese satellite.

[Zenaan Harkness]

On Fri, Aug 05, 2016 at 08:13:39AM +0000, jim bell wrote:
> 
> 
>  From: juan <juan.g71 at gmail.com>
> On Fri, 5 Aug 2016 11:29:07 +1000
> Zenaan Harkness <zen at freedbms.net> wrote:
> 
> >> It does sound like the obvious is being missed - so entangled photon
> >> paris can be created, and we can know at one end, if the photon at the
> >> other end is "read",

I believe this statement was quite ambiguous, and should have been
written by my ever so humble self as follows:

   -  so entangled photon pairs can be created, and we can know at one
      end, if the photon at the other end has been "read"

note the "has been" replacing "is"!  With, of course, "has been" meaning
"happened at a time up to and including --now--".


> >> and this apparently happens at at a minimum of
> >> 10k.c;
> > 
> >> Surely, one could simply create a suitably large number of entangled
> >> photon pairs, as an array, and then read them, or not read them, at
> >> the end you want to "send" information from, and "detect" (so this
> >> weird quantum mechanics story goes) those reads at the other end.
>
> I can, but don't call me Shirley.
>
> >> Read + Not read = 1 bit.
> > >What seems to be implied in the stories so far is that the information
> > >must be transmitted through changing states of a single entangled
> >> photon
> >> - which assumption makes no sense at all. There's a purported
> >> phenomena, use it!
> 
> >    Yep. It either works or not. And if it works you should be able
> >   to get some 'macroscopic' result/data transmission (of course
> >    the micro/macro divide is just pseudo-scientific, absurd
> >    bullshit)
> 
> I thought of an interesting thought-experiment that may clarify the
> situation.It's new, and doesn't precisely follow quantum, but here
> goes:
>
> Suppose you have two points in space,  for concreteness 1 light-year
> apart.There is a Star-trek type transporter, one pad at each location.
>  But it canonly transport information, not matter.

> Place a data file on the first pad, press the button, and it will be
> virtuallyinstantly sent to the second pad, 1 l.y. away.  But the
> 'gotcha' is that itwon't arrive in plaintext:  It will be encrypted.
>  It can still be read as seemingly random, encrypted bits, and there
> are crc's, checksums,'fire codes', and other verifications that the
> whole file arrived successfully.

> The first (originating) transporter also generates a key, which can be
> usedto decrypt the file.  Problem is, it can only be sent by laser,
> and thus at 'c'.Send the file, and it appears virtually instantly at
> the far end.  But its actualunencrypted contents cannot be read in
> plaintext.  The data packet mustbe placed on the shelf, and after one
> year the photon-beam containing thedecrypt code packet arrives.  
> (Possibly with the addition of a copy of the original message, for
> additional certainty that they got the original message.).

> They apply the decrypt key to the packet which arrived one year
> before.The decrypt works, and they discover that the message is
> identical to theone sent by laser one year previous, and was just
> received a moment before.

Cute concept :)

Possibly a good analogy, but I ain't Schroedinghy, so dunno how
analogous it is :)


> Wouldn't it be possible to argue that the data MUST have travelled at
> 10,000+'c'?

Absolutely, in this example case, but I have no idea if your idea is
suitably analogous or not sorry.


> If it hadn't, how could the values of data on the
> printout have been determined'instantly'?

> Question:  At what rate did that "instantaneous" data transfer occur?

If it is actually instantaneous, then the rate is infinite, in the
dimensions in which we make our observations.

If a second primitive is ever theorized and later experimentally shown
to exist, then I am confident we shall see a flurry of mathematical
modelling and comparison and elimination, and something "conclusive" and
"well duh" paraded around.


>  Well,it sure looks like it was indeed "instantaneous".  The original
> packet arrived,it was placed on the shelf in seconds.  But, the

Your experiment shows possibly that we simply do not understand either
the entangled experiment, or why it cannot be used to transmit
information "simultaneously", since synchronization can indeed happen in
wall clock time, as long as the two ends are far enough apart - e.g. 1
light year, or 1 light minute apart.


> information within it wasn'tactually readable for one year, until the
> decrypt key arrived.  Can we say thatthis information arrived after
> one year, and thus at an effective speed of 'c'?  If it is the former,
> somehow the idea that information can't be transmitted at fasterthan
> 'c' is invalid.  If it's the latter, this appears to confirm that
> limit.

> Which is it?

> You said:  "Yep. It either works or not."

> The 'gotcha' is that whether it "works" or not is dependent on your
> definition of the word, 'works'.

No, the statement is: either the remote side can determine that I have
made an observation or not - this is a basic premise, which is either
true or not.

If it's not true, we do not understand this new toy called quantum
entanglement, and therefore cannot reason about the problems nor
theorize as to why it cannot be used for information transmission.


>  Does it seem to transmit the data
> virtually instantly?  Yes.  Is that information available immediately?
>  No.

Not in your hypothetical.


> It takes a year to learn the contentof that encrypted file.

> Is the limit of 'c' violated?   I don't know.  What do you think?

It certainly would be - although you cannot verify nor decrypt the
transmission for 1 year, you can prove the transmission actually
happened 1 year ago.


We seem to be missing some vital part of the problem, I guess...