## What is a quantum computer?

How does science work? And what's all this about quantum mechanics?

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Obvious Leo
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### Re: What is a quantum computer?

We need to exercise some caution when we assume that a mathematical principle can be extended to a real-world scenario and infinite divisibility is one such principle. Leibniz was aware of this when he spoke of the philosophy of the calculus, a mathematical tool which can be used to describe the way a physical system tends but not its actual physical state. If we define time as a metric for measuring the rate of change in a physical system then we readily arrive at a definition for a no-further-divisible interval of time. It becomes the briefest possible interval of time in which we can meaningfully say that something has actually happened and in contemporary physics this interval has a value of 5.4 x 10(-44) seconds, an interval known as the Planck interval. Thus we mustn't think of time as passing in a continuous flow but rather as something which passes in a sequence of absurdly brief stuttering Planck steps.

However the truly interesting thing about this from a metaphysical point of view is what I call the elephant in the room of GR. Before the publication of GR it was assumed that time passes at a constant speed for all observers but GR showed this assumption to be false. The speed at which time passes is entirely determined by gravity and this must obtain all the way down to the Planck scale. Photons are quanta of energy which can only change their energy state at the speed of light and because the speed of light is finite we can think of the briefest possible interval of time as the time it takes for a photon to change from one energy state to another. Therefore this too is entirely determined by gravity. The mathematical relationship between time and gravity is inversely logarithmic in its nature, which means that if we specify one we automatically specify the other so time and gravity can be regarded as two different ways of expressing the same phenomenon, which I define as the processing speed of physical reality. This is a very significant unification of concepts because it means that time, gravity and the speed of light can all be quantised equivalently. This is quantum gravity but this interpretation of GR cannot be accommodated within conventional spacetime physics. Quantum mechanics is entirely predicated on SR and not on GR, and SR is a model which ignores gravity because at the time when SR was published the inversely logarithmic relationship between time and gravity was unknown. SR assumes that the speed at which time passes is the same for all observers and is therefore not relativistic enough. GR gets around this problem by introducing the notion of spatial expansion and curvature but this is an action-at-a-distance idea rather than a mechanical construct because space is purely a mathematical object and not a physical one. This leaves QM high and dry because QM is a gravity-less paradigm modelled in the "flat" space of SR, rather than in the "curved" space of GR. In other words QM completely ignores the fact that time does not pass at a constant speed within the atom. This is the fundamental flaw in QM which leads to all the so-called quantum "weirdness" but the root of the problem lies even deeper than that. The root of the problem actually lies in the fact that the universe is not a continuum of time and space at all because space is only an observer effect, as Leibniz, Kant and various others have said all along. The real universe is actually a continuum of time and gravity which the observer merely constructs within his consciousness into a continuum of time and space.

"Collapsing a wave function" is simply a fancy term for making an observation and an observation is an act of cognition. When we make an observation of the physical world what our consciousness is doing is according a spatio-temporal extension to an event which actually has an extension in time alone. We are spatialising an interval of time which has elapsed between ourselves and an event which has previously occurred in our own past. This interpretation accords perfectly with the evidence but not with the current narrative of the evidence. However it makes every single paradox and metaphysical absurdity in contemporary physics simply vanish so in my opinion it simply cannot be false.

Furthermore it is a hypothesis which yields a testable prediction which would unambiguously falsify current theory.

Arising_uk
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### Re: What is a quantum computer?

Obvious Leo wrote:...
Furthermore it is a hypothesis which yields a testable prediction which would unambiguously falsify current theory.
I'll bite, which is?

Obvious Leo
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### Re: What is a quantum computer?

Arising_uk wrote:
Obvious Leo wrote:...
Furthermore it is a hypothesis which yields a testable prediction which would unambiguously falsify current theory.
I'll bite, which is?
I want to maintain the suspense but an overview for an appropriate experiment is included in my synopsis here:

https://austintorney.wordpress.com/2015 ... n-de-jong/

What this theory also predicts is that when a photon splits into two daughter photons after striking a semi-silvered mirror then information transfer between the daughter photons will APPEAR TO take place at a speed faster than the speed of light. In fact nothing can happen faster than the speed of light so this spooky action at a distance which tormented Einstein for decades is nothing more than an observer effect. The same phenomenon also accounts for the so-called spatial wormhole beloved of the science fiction writers, because when QM and GR are unified in this way the wormhole and quantum entanglement are merely two different ways of expressing the same physical phenomenon.

Philosophy Explorer
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### Re: What is a quantum computer?

Two things in this update:

1) IBM has a quantum computer and would let anyone use it.

2) This can be taken as further evidence for a quantum computer:

Also want to mention there are different types of quantum computers. For example there is a universal quantum computer (which can do many tasks simultaneously) which isn't your run-of-the-mill quantum computer. The universal quantum computer has been forecasted to be coming out within the next five years.

PhilX

wtf
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### Re: What is a quantum computer?

Philosophy Explorer wrote:Two things in this update:

1) IBM has a quantum computer and would let anyone use it.

2) This can be taken as further evidence for a quantum computer:

Also want to mention there are different types of quantum computers. For example there is a universal quantum computer (which can do many tasks simultaneously) which isn't your run-of-the-mill quantum computer. The universal quantum computer has been forecasted to be coming out within the next five years.

PhilX
LOL. When I clicked on the link I was expecting something new. This is D-Wave. D-Wave is to quantum computing what California's "high speed" rail is to high speed rail. Hype and not reality.

Philosophy Explorer
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### Re: What is a quantum computer?

wtf wrote:
Philosophy Explorer wrote:Two things in this update:

1) IBM has a quantum computer and would let anyone use it.

2) This can be taken as further evidence for a quantum computer:

Also want to mention there are different types of quantum computers. For example there is a universal quantum computer (which can do many tasks simultaneously) which isn't your run-of-the-mill quantum computer. The universal quantum computer has been forecasted to be coming out within the next five years.

PhilX
LOL. When I clicked on the link I was expecting something new. This is D-Wave. D-Wave is to quantum computing what California's "high speed" rail is to high speed rail. Hype and not reality.
Companies are willing to spend good money (in this case \$15 million) and since it's their business, I'm not going to second guess them.

PhilX

wtf
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### Re: What is a quantum computer?

Philosophy Explorer wrote: Companies are willing to spend good money (in this case \$15 million) and since it's their business, I'm not going to second guess them.
Yes but here you are using money spent by a wealthy company (15M? IBM's 2015 revenues were \$81 BILLION) as a proxy for the scientific validity of quantum computing.

Surely you agree that if someone wrote a paper that said, "Quantum computing must be practical because IBM tossed their pocket change at it," that would not pass peer review as scientific reasoning.

Philosophy Explorer
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### Re: What is a quantum computer?

wtf wrote:
Philosophy Explorer wrote: Companies are willing to spend good money (in this case \$15 million) and since it's their business, I'm not going to second guess them.
Yes but here you are using money spent by a wealthy company (15M? IBM's 2015 revenues were \$81 BILLION) as a proxy for the scientific validity of quantum computing.

Surely you agree that if someone wrote a paper that said, "Quantum computing must be practical because IBM tossed their pocket change at it," that would not pass peer review as scientific reasoning.
Money talks.

Incidentally the "MIT expert" Scott Aronson seems to be lessening his resistance to D-Wave from the last article I read on him. My belief is that 2015 marks the year that quantum computers came about.

PhilX

wtf
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### Re: What is a quantum computer?

Philosophy Explorer wrote: Money talks.
If IBM put \$15B into it, I'd be impressed. At \$15M, that's about .00018 of their annual revenue. Not impressed.
Philosophy Explorer wrote: Incidentally the "MIT expert" Scott Aronson seems to be lessening his resistance to D-Wave from the last article I read on him. My belief is that 2015 marks the year that quantum computers came about.
I took a quick glance at his end-of-year remarks on D-Wave and saw no such lessening. Link please? Perhaps we're reading the same thing and understanding it differently.

Philosophy Explorer
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### Re: What is a quantum computer?

Wtf said:

"If IBM put \$15B into it, I'd be impressed. At \$15M, that's about .00018 of their annual revenue. Not impressed."

Except we're not talking about IBM here. A completely different and smaller company (still, however, \$15 million is \$15 million and I'm impressed).

I'll look for the link later.

PhilX

Philosophy Explorer
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### Re: What is a quantum computer?

Scott Aronson's blog contains a conciliatory tone:

http://wavewatching.net/category/d-wave/

"Scott Aaronson's blog entry on the matter strikes a (comparatively) conciliatory tone. One of his comments explains one of the reason for this change:

'[John Martinis] told me that some of the engineering D-Wave had done (e.g., just figuring out how to integrate hundreds of superconducting qubits while still having lines into them to control the couplings) would be useful to his group. That’s one of the main things that caused me to moderate a bit (while remaining as intolerant as ever of hype).'"

PhilX

wtf
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### Re: What is a quantum computer?

Philosophy Explorer wrote:Scott Aronson's blog contains a conciliatory tone:

http://wavewatching.net/category/d-wave/

"Scott Aaronson's blog entry on the matter strikes a (comparatively) conciliatory tone. One of his comments explains one of the reason for this change:

'[John Martinis] told me that some of the engineering D-Wave had done (e.g., just figuring out how to integrate hundreds of superconducting qubits while still having lines into them to control the couplings) would be useful to his group. That’s one of the main things that caused me to moderate a bit (while remaining as intolerant as ever of hype).'"

PhilX
If someone named Henning Dekant says that Aaronson's opinion has moderated, I'll take that as weak evidence of your thesis. Which is better than none, and as an Aaronson fan I'll take this as a datapoint of interest.

But still, fifteen million dollars. That's rounding error on the coffee budget over at IBM.

Philosophy Explorer
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### Re: What is a quantum computer?

wtf said:

"But still, fifteen million dollars. That's rounding error on the coffee budget over at IBM."

That would be an order of magnitude of three for you on an annual basis. I'm sure all of the top management were involved on the decision to purchase the annealing quantum computer and I'm sure they must have investigated D-Wave for months before coming to that decision. And the purchasing company would've made sure that they got guarantees on the performance of the computer. Surely no trivial matter.

PhilX

Cerveny
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### Re: What is a quantum computer?

I am to refresh rather mild discussion: The brain acts a quantum computer, we can imagine that it interprets reality via, say, fourier/laplace/other transformation...

wtf
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### Re: What is a quantum computer?

Cerveny wrote:I am to refresh rather mild discussion: The brain acts a quantum computer, we can imagine that it interprets reality via, say, fourier/laplace/other transformation...
It would be astonishing if qubits were stable in the moist warm brain. There's no evidence for your claim.

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