24 March 2011
Subject: NASA's Mission
...as only NASA can
"One of the amazing
things about entanglement is that it connects objects over arbitrary distances,
so that in principle the two clocks could be started and stopped simply
by acting on only one of them," said Adami. "However, no workable protocol
has been found to date to achieve that."
Dear Dr. Adami,
Perhaps the reason why you're trying to discover some workable protocol is that you haven't read John Polkinghorne's "Quantum Theory, A Very Short Introduction",
Let me quote from p. 81: "It is as if a singer at 1 was singing a random series of notes and a singer at 2 was also singing a random series of notes and only if one were able to hear them both together would one realize that the two singers were in some kind of harmony with each other."
In order to "hear them both together", you need a relativistic quantum theory of measurement and Lorentz invariant nonlocality. I'm afraid you are not able to deliver such theory. If you were, you would have solved many tasks undertaken by NASA and by the theoretical physics community wrestling with quantum gravity.
The good news is that the human brain might -- just might -- be able to explore quantum nonlocality,
If you know some open-minded physicist from NASA, please drop me a line.
John S. Bell
RE: Chris Adami, Jonathan
P. Dowling. Quantum Computation --The Ultimate Frontier. Thu,
7 Feb 2002 01:26:27 GMT,
C. Adami and J.P. Dowling: "Quantum computing requires
the creation, manipulation, and detection, of entangled qubits."
Dear Dr. Adami:
Some history. In my previous email from Fri, 08 Feb 2002 08:17:35 +0200 [Ref. 1], I expressed my sharp disagreement with your ideas about some "quantum computation". I referred you to my email to Dr. Brukner, in which I believe have stated my position very clearly.
Regrettably, I didn't hear from you, but received a very insulting remark from your colleague and co-author Jonathan P. Dowling, "Never give oxygen to Morons..... " [Ref. 2], to which I replied twice [Ref. 3 and Ref. 4], and from now on all my email to your co-author Dr. Dowling will be automatically deleted [Ref. 5].
I think this is a very juvenile behavior on behalf of Dr. Jonathan P. Dowling: instead of answering my sharp criticism, he's now playing the role of some insulted ostrich. The issue of quantum computing -- if any -- is more than serious, and no one should avoid criticism, just as I asked you for your comments and critical remarks in my first email [Ref. 1].
Let's cut off our emotions and put our cards on the table. I will outline some (not all) of the main arguments against the possibility for "quantum computing", and then will state, in plain English, the conditions under which I will accept your point of view. Then I will respectfully ask you to answer my criticism, and also to declare the conditions under which you will accept my viewpoint. Fair enough, right?
I have two main objections pertaining to the nature of probabilities in QM, and subsequently to your belief that quantum computing could be possible in practice, not just on paper, such as your "Quantum Computation --The Ultimate Frontier" addressed to the general audience and your contractors from U.S. Department of Defense.
Let me quote from your paper.
On p. 3 from you PDF file quant-ph/0202039, you touched briefly the measurement problem in QM and wrote [quote] "the schism between quantum and physical realism need not bother us as long as we keep aware that “seeing” an object take on a particular state (observing its physical reality) may not reveal to us the wave function of this object (its quantum reality)".
Then you went on by stating: "Thus, N qubits can, using the entanglement operation, be brought into a superposition of 2N terms, each of which can be thought of as encoding a particular classical state. (Any product state can be viewed as a “classical” state.) The power of quantum computation is that the 2N terms in superposition (3) can be operated on simultaneously with a unitary quantum operator U (this is known as quantum parallelism). Of course, you need to make sure that the entanglement extends to all these qubits, and these qubits only. Should a few qubits become entangled with (3) inadvertently (which means, should you not be aware that this happened), the wonderful properties of the entangled states will have turned from boon to bane: Instead of a coherent superposition you will be handed an uncertain mixture of states, useless for computation. In a manner of speaking, then, all quantum computations ought to be performed in “total darkness” (since photons are perfect qubits on their own), and at zero temperature. Even “looking” at your end result could prove to be hazardous if special precautions are not taken."
Thus, the magic of quantum computation depends crucially on the so-called quantum parallelism. The key problems here are "simultaneously" and "in total darkness". You claim that these well-known problems were solved by transferring techniques from classical error correction, referring to papers by Shor and Preskill (p. 4). I disagree. The fairy tale of quantum computation runs against STR. We don't have a theory of Lorentz invariant nonlocality or a relativistic quantum theory of measurements.
We know very well that this is not possible. No physical clock could measure the "duration" of superposed states nor entangled states. If a qubit is in a superposition of "a cat and a dog" [Ref. 6], you will get either a classical dog or a classical cat, but you can not sustain or somehow keep the the quantum system: once you observe a classical cat, the "duration" of its dog-state is zero. Zilch. Non-existent.
Therefore, the idea of error-correction mechanism is not
justified. It presupposes -- tacitly -- that there is an answer to the
first question above. Do you have an answer for it? Please see also Saul
Youseff [Ref. 7].
Objection #2: The whole idea about some real, practical quantum computing depends crucially on the solution to the measurement problem. We don't have it. We do not know the nature of quantum reality, the very same beast we want to employ for "quantum computing". We can only speculate about some 'relational reality', meaning that [psi] is "real only in relation to the interaction that they undergo with the systems they interact with" [Ref. 8].
You and your co-author did acknowledge that “seeing” an object take on a particular state (observing its physical reality) may not reveal to us the wave function of this object (its quantum reality), but claimed that we need not bother about it (cf. above).
Do you know the difference between 'physical reality' and 'quantum reality', to substantiate this crucial claim? I'm afraid this is a rhetoric question: nobody knows the answer.
To sum up, the whole dream about some practical quantum computing is grounded on beliefs and hopes that with some error-correction mechanism one could avoid or bypass -- but not solve! -- the initial problem of reconciling QM with STR, as stressed by Erwin Schroedinger back in 1931.
You can't outsmart Mother Nature. No way.
Now, I declare that I will accept your view iff you can suggest a theory of Lorentz invariant nonlocality.
Please answer my objections above, and then state the conditions under which you will declare that the task for quantum computing is not feasible in principle.
I extend this request to all physicists reading this critical note on "quantum computing", regardless of who their contractor is -- DoD, DERA, or someone else.
Let's put our cards on the table. It's about time.
P.S. Carlton M. Caves, whose work on "quantum computing" is partly sponsored by U.S. Office of Naval Research, also decided to play ostrich [Ref. 9], just like his colleague Jonathan P. Dowling [Ref. 5]. But what if they stand on ONR concrete instead of sand?
[Ref. 1] Message-ID: <3C636D7F.254C704@surfeu.at>
Dear Dr. Adami:
You wrote: "These new man-made quantum states have novel properties of sensitivity and nonlocal activity that have wide application to the development of computers, communications systems, sensors and compact metrological devices - all areas of intense DoD interest."
I'm wondering if you've told your DoD contractors about the whole range of problems with that oxymoron "quantum computer",
"Thus, although quantum mechanics as a science has matured completely, quantum engineering as a technology is now emerging on its own right. It is just a matter of being in the right place at the right time to take full advantage of these exciting new developments."
These "exciting new developments" need a theory of Lorentz invariant nonlocality.
First things first.
I will appreciate your comments and critical remarks.
Dimiter G. Chakalov
[Ref. 2] Message-ID: <3C638B65.88ACE03@earthlink.net>
Never give oxygen to Morons.....
Jonathan P. Dowling, PhD
Quantum Computing Technologies Group, Section 367Jet Propulsion
Laboratory, California Institute of TechnologyMail Stop 126-347, 4800 Oak
Tel: (818) 393-5343
[Ref. 3] Message-ID: <3C639F86.F2507E61@surfeu.at>
On Fri, 08 Feb 2002 00:25:08 -0800, "Jonathan P. Dowling"
Never argue with Jehovah's Witnesses, even if they waste taxpayers' money.
[Ref. 4] Message-ID: <3C63A24C.825E8426@surfeu.at>
On Fri, 08 Feb 2002 00:25:08 -0800, "Jonathan P. Dowling"
You have not learned anything from 9/11. If I was working at DoD, I wouldn't give you a penny until you sort out your mess.
Don't worry, nobody will read this email, your next pay check is safe.
[Ref. 5] Message-ID: <3C646A79.30D8E98@jpl.nasa.gov>
I am now setting up my mail filter to automatically delete
all incoming emails from you or your internet domain,
so don't bother sending me anything anymore.
"Dimiter G. Chakalov" wrote:
> On Fri, 08 Feb 2002 00:25:08 -0800, "Jonathan P. Dowling"
[Ref. 6] E. Joos. Elements of Environmental
"There are many examples, where it is hard to find certain superpositions in the real world. The most famous example has been given by Schrödinger: A superposition of a dead and an alive cat
Psi = |dead cat> + |alive cat>
Psi = |cat> + |dog>"Such a superposition looks truly absurd, but only because we never observe states of this kind! (The obvious objection that one cannot superpose states of "different systems" seems to be inappropriate. For example, nobody hesitates to superpose states with different numbers of particles.)"
[Ref. 7] S. Youssef. Physics with exotic
"With probability theory modified, there is no need for
the usual "wave-particle duality" and one is free to assume, for example,
that a particle in R^3 is somewhere in R^3 at each
time. Introducing such "state spaces" and assuming that probabilities
have a square norm, exotic probabilities acquire the power to predict real
non-negative frequencies and are limited to three algebras: reals, complex
numbers and quaternions.
"It is clear from the exotic probability point of view
that a naive picture of quantum computers doing computations "on all paths
simultaneously" must not be correct. In some sense, the particle can only
do so much because it only, in fact, follows one path through the system."
[Ref. 8] J. Anandan. Causality, Symmetries,
and Quantum Mechanics.
[Ref. 9] From: "Carlton M. Caves" <firstname.lastname@example.org>
I have asked you to quite sending me messages, and since you haven't, I have installed a rule that deletes your messages before I see them.
> -----Original Message-----