On Feb 3, 2013, at 12:42 PM, JACK SARFATTI <This email address is being protected from spambots. You need JavaScript enabled to view it.> wrote:
Fred, I think you are making an error here. The vacuum |0> is as good a state as |1> in Fock space for a given mode-radiation oscillator. DK's eq. 1 is a FOUR PHOTON state - two REAL PHOTONS & TWO VIRTUAL PHOTONS
Note also that Glauber coherent states use |0> in an fundamental way.
quantum optics interferometer experiments use the |0> states e.g. papers by Carlton Caves
http://info.phys.unm.edu/~caves/
http://info.phys.unm.edu/~caves/research.html
http://info.phys.unm.edu/~caves/talks/talks.html
Search Results [PDF]
Quantum-limited measurements: One physicist's crooked path from ... www.phys.virginia.edu/Announcements/Seminars/.../S1466.pd... File Format: PDF/Adobe Acrobat - Quick View physicist's crooked path from quantum optics to quantum information. I. Introduction. II. Squeezed states and optical interferometry. III. ... Carlton M. Caves ... [PDF]
Quantum metrology - University of New Mexico info.phys.unm.edu/~caves/talks/qmetrologylectures.pdf File Format: PDF/Adobe Acrobat - Quick View Carlton M. Caves. Center for Quantum ... Ramsey interferometry, cat states, and spin squeezing. Carlton M. ... Weinstein, and N. Mavalvala, Nature Physics 4, ...
On Feb 3, 2013, at 12:26 PM, fred alan wolf <This email address is being protected from spambots. You need JavaScript enabled to view it.> wrote:
Nick and Demetrios, basic quantum physics tells me that eq. 1 of KISS is a 4-photon state. That is my point. Let the Hamiltonian go. Ergo, to claim it as 2-photon state cannot be correct. Eq. 1 says something about phases as well. If I write a quantum wave function as a sum over i of |ai>|bi>|ci>|di> then there must be 4 objects, not two, regardless of how large is i. Even if |ai> is a sum of possibilities such as (|A1>+|A2>) and similarly for the bi, ci and di states, I still can't get this to reduce to a sum over two particle states. Nicht wahr?
So I am confused how you both seem to see this as OK as far as quantum physics is concerned.
Jack, do you or do you not see my point?
Best Wishes,
I'll quickly respond to Fred's question. The state in eq.1 is perfectly legitimate and has been experimentally realized already. In this scheme it is tacitly assumed that the source S is a down-conversion source, since this is by far the main way in which entangled photon pairs are created. These sources need a pump to stimulate the nonlinear medium (i.e. down-conversion crystal). Usually about one in every million pump photons are split into an entangled pair, each photon of which comes out at a specific angle and energy. The way to create two photons in modes a1a2 is to have the pump come from the bottom and pass upward; the way to create two photons in modes b1b2 is the BACK-REFLECT the same pump downward through the crystal again. So,each run of the experiment is ONE DOUBLE-PASS of the pump through the crystal....most of the times you get nothing and, to very good approximation, the rest of the time you get one pair created (either in a1a2 or b1b2)....Of course there is also the far smaller amplitude of creating two pairs (one in a1a2 and one in b1b2, or two in a1a2, or two in b1b2)....according to the expansion of the Hamiltonian....but these are negligible terms and do not affect the outcomes in all these entanglement experiments. Demetrios
Jack SarfattiOn Feb 3, 2013, at 11:48 AM, JACK SARFATTI <This email address is being protected from spambots. You need JavaScript enabled to view it.> wrote:
I agree with Nick.
On Feb 3, 2013, at 11:25 AM, nick herbert <This email address is being protected from spambots. You need JavaScript enabled to view it.> wrote:
No need for Hamiltonians, Fred. The KISS proposal is as simple as LEGOs. Every part of it is something THAT HAS ALREADY BEEN DEMONSTRATED IN A LAB.
Kalamidas has put these existing Legos together in an imaginative way that seems to permit superluminal signaling.
But probably does not.
If you, Fred, are waiting for a Hamiltonian formulation of this experiment you will be waiting for a long time and will have essentially disconnected yourself from the KISS adventure.
Nick Herbert KISS = Kalamidas's Instant Signaling Scheme ---- end of Nick's message above, I wrote: OK there are two separate issues here.
Question 1: Fred if DK's wave function
Could be made, then do you agree with DK's logic for the rest of the paper.
I think the above wave function is perfectly legitimate in principle although whether one can make it in the lab is another question.
(1) is perfectly sensible in quantum field theory in Fock space.
There are four radiation oscillators with two real photons and two zero point photons distributed among them. The vacuum states |0> are legitimate states.
Question 2. Accepting (1) is DK's logic etc. correct? I think Nick Herbert is working on that question.
I personally am still thinking about the whole thing looking at Mandel as well and trying to understand the whole thing better.
My previous work on the Glauber state distinguishable non-orthogonality loop hole in the no-signaling belief is generally compatible with the spirit of what DK is proposing. I mean
On Feb 3, 2013, at 9:53 AM, fred alan wolf wrote:
Guys and girls,
I don't believe this will work simply because to my knowledge there is no foundation based on quantum physics which supports this initial supposedly 2-particle quantum wave function. What Hamiltonian does it solve? You can always invent quantum wave functions (which are not connected to reality) but to claim this one (which apparently uses 4 photons not 2) has solved the ftl problem is simply bad physics as I see it. If I am wrong here, will somebody explain how this quantum wave function is a two body quantum wave function? Can you show me the Hamiltonian it is solution for?