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Quirky Qualities of Quantum Optics

Posted October 13, 2007 8:17 AM

A one-way quantum computation process that makes use of a two-photon four-qubit cluster state has been demonstrated by a collaborative group from German and Chinese universities. The high-fidelity technique is less vulnerable to background noise. Meanwhile, Italian researchers have demonstrated the quantum non-commutative effect — adding then subtracting the mean number of photons in a beam did not yield the same results as performing those operations in reverse. Makes your head hurt, no?

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Guru
Popular Science - Cosmology - New Member United States - Member - New Member

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#1

Re: Quirky Qualities of Quantum Optics

10/14/2007 3:09 PM

"adding then subtracting the mean number of photons in a beam"

I would like to know just how one can add, or subtract, a specific number of photons in any situation. I've heard comments from various threads on CR4 concerning such things as "emitting a single photon", etc. How is such a thing possible? Is there a way to actually count the photons as they leave a source?

-John

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Anonymous Poster
#2
In reply to #1

Re: Quirky Qualities of Quantum Optics

10/14/2007 8:49 PM

I guess I'm from Missouri on this one. You'll have to show me that it is possible.

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Guru
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#3
In reply to #1

Re: Quirky Qualities of Quantum Optics

10/15/2007 3:09 PM

Again with the circular math!

Exactly, It is impossible to count a single proton in these tests. You are dealing with an uncountable "quantum" of photons. Also to measure a 'mean' number of photons after disrupting the beam is just a wild guess. If you scramble the phases, you cannot get an accurate measurement at any phase. This is a stupid exercise in two dimmensional math with a three dimensional environment.

Here is the exact equation

(A X light) + chaos (- 1 light + 1 light) = (A X Light) + Chaos

A X light on both sides cancel. The -1 and + 1 cancel.

You are left with measuring the chaos.

Surprise!!! It is different every time you measure it

I hope they are not trying for another grant.........

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Guru
Popular Science - Cosmology - New Member United States - Member - New Member

Join Date: Apr 2007
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#4
In reply to #3

Re: Quirky Qualities of Quantum Optics

10/15/2007 5:54 PM

Hi techno,

Your point is well taken. However, there must be some validity to such research?

I recall a discussion on another CR4 thread about the double slit experiment. Researchers were surprised that the same refractance pattern was observed when a single photon was released toward the double slit as was observed when a beam of light was directed toward the double slit.

I am truly puzzled by this and would humbly like an answer that's not off the deep end of the mathematics spectrum (in other words a layman's answer).

Are you listening Europium, Jorrie, et. al. ?

Regards,

-John

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Guru
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#5
In reply to #4

Re: Quirky Qualities of Quantum Optics

10/16/2007 2:30 PM

The real problem is that the scientists have to beg for money to do research. When they have produced nothing, they baffle with BS to keep the money coming in. The problem is that most people with the money rarely underestand the experiments and think just like you. "there must be some validity to such research?" or "This looks so cool I might make some money off of it." What is really sad is that many times they are simply repeating someone elses work.. The money, that could have been spent on real reaserch, is wasted on some career student who cannot afford to leave school because the student loans have piled up.

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