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Profile janneseti
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Message 1730092 - Posted: 29 Sep 2015, 14:21:57 UTC - in response to Message 1730087.  
Last modified: 29 Sep 2015, 14:33:07 UTC

Still would like to know why so called quantum computers are good at factoring and exactly why and how the "circuitry" and logic works.

Hmm.
Quantum computers are only good at factorizing.
Classical computers are not.

And exactly why and how the "circuitry" and logic works.

Their is no such thing as Exact events in the quantum world.
Only Probabilities.

Here is what you have to know if you want to know how a quantum computer works.
http://www.quantiki.org/wiki/Basic_concepts_in_quantum_computation
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Profile William Rothamel
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Message 1730097 - Posted: 29 Sep 2015, 14:38:35 UTC - in response to Message 1730092.  
Last modified: 29 Sep 2015, 15:06:08 UTC

Their is no such thing as Exact events in the quantum world.
Only Probabilities.

Well then if true then we could never have a useful result nor a piece of actual hardware.

It's time for all of us pseudo intellectuals to come out from hiding behind the term "quantum" and get to discussing real logic, problems, circuitry or small atomic structures and results in the Quantum world.

There are in fact true and actual events in the quantum world or else we would not have spectroscopy. Perhaps the term "quantum" has been applied to too many things that we don't fully understand or have a good explanation for.
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Message 1730103 - Posted: 29 Sep 2015, 14:50:08 UTC - in response to Message 1730092.  
Last modified: 29 Sep 2015, 15:08:32 UTC

Thank you for the reference on quantum computation. Just like the Hoopla over threshold logic and artificial neurons 50 years ago it all appears to decompose into Boolean logic and binary circuits. Neurons never caught on since digital was faster than analog and digital representations of artificial neurons used lots of unnecessary hardware. The logical power of these neurons also decomposed into binary and Boolean logic.

Perhaps Glorioso and I should come out of retirement and set out to debunk quantum computing as a miracle hope for the future. The work that was done by Bob and I on Artificial Neurons/intelligence is not in machine-readable form since it was done 50 years ago --or else I would offer it for anyone interested in the topic.

Truthfully though I will be contrite and take my CD course on quantum technology and wade though the Bras and the Kets once again this time holding back my distaste for pedantic flummery. I am sure that the field is fully worthy of support and experimentation--I am simply expressing my frustration with not having every-day explanations in known scientific terms for its perceived and actual hardware structure and benefits. As for Quantum Mechanics :::: I know nothing, but I know what I don't know
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Message 1730107 - Posted: 29 Sep 2015, 14:56:54 UTC - in response to Message 1730103.  
Last modified: 29 Sep 2015, 15:08:14 UTC

IBM is investing heavily on quantum computers research. I don't think IBM is going after illusions.
Tullio
E.G. See IBM Research Division, T.j.Watson Research Center, New York, USA
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Message 1730109 - Posted: 29 Sep 2015, 15:04:35 UTC - in response to Message 1730107.  
Last modified: 29 Sep 2015, 15:07:18 UTC

By the term "Quantum Computers" they may be referring to making faster computers by going to ever smaller structures and data paths. This might lead to using singe atoms as storage and logic switches. This may be termed quantum since it appears at the very small structures and might make use of the quantumized energy levels and spins of electron orbits.

The question I have is will the underlying logic be Boolean or will it somehow involve the uncertainty of a third state ?
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Message 1730111 - Posted: 29 Sep 2015, 15:08:57 UTC - in response to Message 1730109.  

Ask IBM.
Tullio
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Message 1730251 - Posted: 30 Sep 2015, 4:41:27 UTC - in response to Message 1730109.  
Last modified: 30 Sep 2015, 4:53:27 UTC

This may be termed quantum since it appears at the very small structures and might make use of the quantumized energy levels and spins of electron orbits.

To me that's the very definition of a quantum computer.

The question I have is will the underlying logic be Boolean or will it somehow involve the uncertainty of a third state ?

The underlying logic is Boolean. True or false. Nothing else.
The superpositioned state is "only" a sort of a mixed mirror of the two "normal" states.

btw. classical computers has Boolean values with three values:)
The third value is called "undefined" and I wonder how many programmers who knows about it...
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Message 1730258 - Posted: 30 Sep 2015, 5:16:19 UTC

Quantum computing is only a part of quantum information processing, which sheds a new light on quantum mechanics. The research done on quantum computing since the days of Richard Feynman has produced an interpretation of quantum mechanics which goes beyond the Copenhagen interpretation of the Twenties, and this is perhaps the major achievement of research on quantum computing.
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Message 1730273 - Posted: 30 Sep 2015, 6:20:02 UTC - in response to Message 1730258.  

The research done on quantum computing since the days of Richard Feynman has produced an interpretation of quantum mechanics which goes beyond the Copenhagen interpretation of the Twenties, and this is perhaps the major achievement of research on quantum computing.
Tullio

Fyenman presented his idea with his own new QM diagrams to Niels Bohr and others at a conference.
Niels said "You cannot do that!"
Anyway. Those diagrams are still used.
The two Feynman diagrams for an electron-positron scattering.

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Message 1730310 - Posted: 30 Sep 2015, 10:47:22 UTC

It seems that D-Wave has sold a 1000 qubit computer to NASA and Google. Price is not specified. They will cooperate in research.
Tullio
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Message 1730316 - Posted: 30 Sep 2015, 12:00:38 UTC - in response to Message 1730310.  
Last modified: 30 Sep 2015, 12:17:53 UTC

The Fridge.
http://www.dwavesys.com/d-wave-two-system
Power and Cooling
“The Fridge” is a closed cycle dilution refrigerator
The superconducting processor generates no heat
Cooled to 180x colder than interstellar space (0.015 Kelvin)

But where is the quantum computing?
A lattice of 1000 tiny superconducting circuits, known as qubits, is chilled close to absolute zero to get quantum effects

There are no tiny circuits, known as qubits.
You cannot make circuits at atomic levels.

The Revolutionary Quantum Computer That May Not Be Quantum at All
http://www.wired.com/2014/05/quantum-computing

I'm getting cooled feet:)
https://youtu.be/CMdHDHEuOUE
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Message 1730340 - Posted: 30 Sep 2015, 14:18:28 UTC - in response to Message 1730251.  

The third value is called "undefined"


I believe in logic design that is actually a "Don't Care" that's what I remember from my early days working in digital computers.
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Message 1730341 - Posted: 30 Sep 2015, 14:18:31 UTC - in response to Message 1730251.  
Last modified: 30 Sep 2015, 14:20:05 UTC

Thank you all for the responses--I am taking my course in Quantum Mechanics and will explain any enlightenments if I actually achieve them
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Message 1730347 - Posted: 30 Sep 2015, 14:33:14 UTC - in response to Message 1730316.  
Last modified: 30 Sep 2015, 14:36:47 UTC

finding the solution to mathematical conundrums with lots of constraints, like the best path among many possible routes to a destination


Here's some thoughts on these high flown statements:

This type of problem is a linear programming problem which basically is solved by tree-pruning algorithms that produce a solution that is as good as can be for the expenditure of computing time and money that one is willing to put forth. A significant contribution was made by Narendra Karmakar of Bell Labs--he was there as was I in the 80's.

His algorithm used hyper -geometry to explore the solution space much more efficiently. It's hard to imagine that today's super-computers using this algorithm could be beaten in any kind of reasonable time by whatever perceived advantage that a quantum computer is alleged to have.

perhaps I am a bit of a Luddite or at least a Skeptic--stuck in the past--I am easily convinced by demonstrated facts however.
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Message 1730381 - Posted: 30 Sep 2015, 15:59:19 UTC

Have you ever tried to calcolate the Ackermann function? It is a recursive function of two integer variables and can kill any computer if you try to calcolate ack(5,5) or higher. To iterate is human, to recurse is divine.
Tullio
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Message 1730400 - Posted: 30 Sep 2015, 16:39:04 UTC - in response to Message 1730340.  
Last modified: 30 Sep 2015, 17:01:31 UTC

The third value is called "undefined"


I believe in logic design that is actually a "Don't Care" that's what I remember from my early days working in digital computers.

And "N/A" for Not applicable.
The problem starts when you are storing Boolean values in a database.
When programming an
IF true THEN do something
you miss all the records that are N/A!
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Message 1731978 - Posted: 5 Oct 2015, 2:58:05 UTC - in response to Message 1730341.  
Last modified: 5 Oct 2015, 3:02:15 UTC

I am proceeding with answers to how a "quantum" computer might work. I have now learned that the underlying logic in the quantum world is not the classical Boolean logic defined by set theory but rather it's logic is based on Vector Spaces over the complex numbers (Hilbert Spaces). I hope to explain more in the near future.
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Message 1732002 - Posted: 5 Oct 2015, 7:45:21 UTC - in response to Message 1731978.  

I am proceeding with answers to how a "quantum" computer might work. I have now learned that the underlying logic in the quantum world is not the classical Boolean logic defined by set theory but rather it's logic is based on Vector Spaces over the complex numbers (Hilbert Spaces). I hope to explain more in the near future.


Looking forward to it. Quantum computing seems like one big mystery to me but oh so interesting.
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Message 1732006 - Posted: 5 Oct 2015, 8:08:29 UTC - in response to Message 1731978.  

I am proceeding with answers to how a "quantum" computer might work. I have now learned that the underlying logic in the quantum world is not the classical Boolean logic defined by set theory but rather it's logic is based on Vector Spaces over the complex numbers (Hilbert Spaces). I hope to explain more in the near future.

All quantum theory is based on Hilbert spaces, which are Banach spaces plus s scalar product. This is the classical Dirac formulation of quantum mechanics, but scalar products of Hilbert space vectors can produce complex fanctions as in the Schroedinger equation.
Tullio
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Message 1732019 - Posted: 5 Oct 2015, 10:19:36 UTC
Last modified: 5 Oct 2015, 10:41:56 UTC

http://www.bbc.com/news/science-environment-11998687

Dr Brembs and others have used mathematical models to simulate brain activity on a computer, finding that what worked best was a combination of deterministic behaviour and what is known as stochastic behaviour - which may look random but actually, in time, follows a defined set of probabilities.
This "stochasticity" shows up in, for example, earthquakes. While they cannot be accurately predicted, a given fault will over time show earthquake timings that neatly fit a curve.

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