What is a quantum computer?

[Arising_uk]

... Imagine NASA being able to use quantum computers to optimize the flight trajectories of interstellar space missions, ...

I'd prefer them to just concentrate on getting around the Solar system first.

FedEx being able to optimize its delivery fleet of trucks and planes, ...

Trying paying the drivers more.

an airport being able to optimize its air-traffic control grid, ...

Sounds useful but is there an actual issue here?

the military being able to crack any encryption code,

Including their own? So no more encryption then, don't know if that would be a good or a bad thing.

or a Big Pharma company being able to optimize its search for a breakthrough new drug.

I doubt this is why they don't search for such things and if they have new computing powers I think the new drugs will be for things that make the most profit and not the most beneficial.

[wtf]

... it may be a useful mental shift or metaphor

Of course. I love metaphors. The statement I objected to was not, "A computation is a metaphor for how the universe works," but rather, "The universe IS a computation." Big dif.

[Arising_uk]

Of course. I love metaphors. The statement I objected to was not, "A computation is a metaphor for how the universe works," but rather, "The universe IS a computation." Big dif.

Never said scientists make good philosophers

Given that some physicists appear to be trying to make infomation a substance of the world then a computation might well be the case. Some kind of 3-d planck-bit cellular automata with the world not being a simulation nor an emulation but just a pattern produced as a by - product of the actual calculations a la Conway's Game of Life.

[Obvious Leo]

wtf. I don't think we're on the same wavelength when speaking of a UTM. I use the term in its most fundamental theoretical sense as a reality MAKER. Deutsch speaks of a UTM as a universal VIRTUAL reality maker but I apply this idea to the universe as a whole. I suggest you read this before I comment further.

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

I'm not sure if sanity comes into it nor whether it's true or not but my philosophical take is that it may be a useful mental shift or metaphor that produces new ways of thinking about things as this does appear to have happened in the past.

This is essentially what I'm talking about. Redesigning physics as an information theory will inevitably lead to new physics but more importantly it will lead to a new way of thinking about physics which will unify the physics we already have. We must never allow ourselves to forget that the current models are mutually exclusive and collectively describe a universe which makes no sense. Thomas Kuhn spoke of this in terms of a paradigm shift and this is exactly what I reckon defining reality as a computation will achieve. Reality is not something which is simply out there. Reality is something which is continuously being MADE.

Another popular theory is that the universe is a hologram.

The computational paradigm does not regard the universe as a hologram and this is a very important distinction to make between it and the current models of physics. Instead it defines what the observer observes as a hologram, which is a simple restatement of the Kantian metaphysic. It means that what our current models of physics are modelling is a hologram but insists that these models are not modelling the real universe. The UTM can then be regarded as the Noumenon which underpins the phenomena of our observation.

Funny how you appeal to mainstream physicists and yet dislike mainstream biologists?

Biologists have always known that the reason they can only make probabilistic predictions in their science is because they are modelling a non-linear dynamic system. In fact this is well known to every science except physics which persists in its Newtonian fairyland. The simple truth is that the universe is not a Newtonian entity and the evidence for this is staring us in the face. The arrow of entropy is going the wrong way for it to be such.

Philosophy Explorer wrote:
... Imagine NASA being able to use quantum computers to optimize the flight trajectories of interstellar space missions, ...

I'd prefer them to just concentrate on getting around the Solar system first.

Even in principle it will NEVER be possible to precisely predict both the location and momentum of a cosmological body, any more than this can be done for a subatomic particle. These are non-computable functions because of relativity, something which has been known since Newton and the three-body problem. This is also why Poincare rejected the 4D manifold.

[Obvious Leo]

Of course. I love metaphors. The statement I objected to was not, "A computation is a metaphor for how the universe works," but rather, "The universe IS a computation." Big dif.

Never said scientists make good philosophers

Given that some physicists appear to be trying to make infomation a substance of the world then a computation might well be the case. Some kind of 3-d planck-bit cellular automata with the world not being a simulation nor an emulation but just a pattern produced as a by - product of the actual calculations a la Conway's Game of Life.

I've repeatedly referred to Conway's Game of Life as a theoretical mechanism for a reality generator at the Planck scale and then enfolded this concept into the broader Mandelbrot set. This is how von Neumann saw the UTM before Mandelbrot even arrived on the scene. However none of these ideas can be applied to the universe unless we first discard the spacetime paradigm and represent the universe as a fractal continuum of time and gravity. I am exclusively a process philosopher of the Heraclitean and Zen persuasion. I simply don't see the world in terms of objects moving in space. I see the world in terms of events occurring in time which my consciousness then constructs into one of objects moving in space. To me collapsing a wave function is simply an act of cognition in which the observer spatialises time, which is exactly the way Leibniz saw it.

[wtf]

wtf. I don't think we're on the same wavelength when speaking of a UTM. I use the term in its most fundamental theoretical sense as a reality MAKER. Deutsch speaks of a UTM as a universal VIRTUAL reality maker but I apply this idea to the universe as a whole. I suggest you read this before I comment further.

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

You referred me to a link of your own writing.

I will read it, ONLY out of respect for the previous thread in which your thinking impressed me. I wonder if you have a strong background in philosophy but don't know the basic definitions of computer science or math. The definition of UTM is extremely clear and it's not what you claim it is. Have you got any references to your alternative conception of a UTM that are not written by you?

[Obvious Leo]

What I'm having the most difficulty with in getting these ideas across is a general reluctance on the part of people to take me literally. This notion of the cosmic computer only makes sense if three-dimensional space quite literally does not exist, just as most of the major philosophical schools have always claimed. This means that it is the physicists who are dealing in metaphors and not the philosophers because the "expanding space" and the "curved space" of relativity become mathematical constructs instead of physical ones.

[Obvious Leo]

wtf. I don't think we're on the same wavelength when speaking of a UTM. I use the term in its most fundamental theoretical sense as a reality MAKER. Deutsch speaks of a UTM as a universal VIRTUAL reality maker but I apply this idea to the universe as a whole. I suggest you read this before I comment further.

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

You referred me to a link of your own writing.

I will read it, ONLY out of respect for the previous thread in which your thinking impressed me. I wonder if you have a strong background in philosophy but don't know the basic definitions of computer science or math. The definition of UTM is extremely clear and it's not what you claim it is. Have you got any references to your alternative conception of a UTM that are not written by you?

Yes. Try the von Neumann architecture. It's quite true that my interest in mathematics and computation is very much from the philosophical perspective but you would be unwise to underestimate the relevance of such a perspective. Physicists may scoff at metaphysics but it doesn't seem to stop them from making metaphysical statements and then disallowing these statements from being scrutinised from a metaphysical perspective.

[wtf]

I searched your essay for "Turing" and found this:

The autopoietic cosmos is a Universal Turing Machine, the cyclical reality maker which programmes its own input.

As the great American statesman Daniel Patrick Moynahan once said: You are entitled to your opinion, but not your own facts.

You have simply mis-stated or misunderstood what a UTM is. I understand that you are approaching the subject from a mythopoetic perspective, but UTM has an agreed-on definition, and "programming its own input" is most definitely NOT it. You are simply wrong on the basic fact of the matter.

Try the von Neumann architecture.

Gosh, Leo, I like you. You're smart. I don't mean to pound you here. But you simply have no idea what you're talking about. It pains me to push back so directly on your ideas. But to the extent that you're serious about being taken seriously, you need to use the standard definitions of things, or else make up your own technical terms and supply working definitions that make sense.

In the beginning of the computer age, in order to program a computer you had to physically hard-wire the circuit board. This ancient practice actually lives on in the present day in the form of "jumpers" that are applied to logic boards or hard drive pins in order to change the behavior of the hardware.

The clever idea of the von Neumann architecture is that just as data can be stored on a permanent backing store ["backing store" is the computer science-y jargon for a hard drive or, back in the old days, a magnetic drum; or in general, any external means of permanent storage], so can the program itself. So on your hard drive you have a program for your browser, and a program for your word processor, and a program for your solitaire game. The operating system kernel has a special routine that loads the program and then executes it on data. That's what the von Neumann architecture is: it's a stored program computer. Every single modern computer from a smartphone to a supercomputer is a von Neumann machine. It's a commonplace commodity.

As a point of advice, you can not have your ideas taken seriously if you deliberately misconstrue the most basic notions of computer science. If you have a computer with a hard drive on which are stored various executable programs, that's a von Neumann machine. It's really as simple as that. Of course 80 years ago that was quite a clever idea, to treat programs as data. But that's exactly what a UTM is as well. You might say that the von Neumann architecture is the real-world implementation of the abstract idea of the UTM. But neither concept supports in the least the claims you're making about them.

It's quite true that my interest in mathematics and computation is very much from the philosophical perspective but you would be unwise to underestimate the relevance of such a perspective.

I don't underestimate the power of mythopoetic or metaphorical thinking. I do say that if you want to be taken seriously, you can't arbitrarily change the definition and meaning of well-understood technical terms such as UTM and von Neumann architecture. Perhaps if you wish to consider a self-programming computer you can call it an FSM, for Flying Spaghetti Monster. At least you would not be subject to the immediate criticisms that you are mis-stating the standard definition of a UTM.

Physicists may scoff at metaphysics but it doesn't seem to stop them from making metaphysical statements and then disallowing these statements from being scrutinised from a metaphysical perspective.

I can't speak for physicists. I do scoff at your redefinition and extravagant claims for UTMs, when your definition (which is not sufficiently fleshed out to even serve as a working definition) is simply wrong.

Perhaps you should take seriously my suggestion to replace your erroneous use of UTM with the idea of a self-programming computer. At least then I could only object, "Well, there isn't such a thing," and you would respond, "Yes, I'm only speaking metaphorically," and we'd be in agreement. But if you tell me a UTM is a self-programming computer, then I must be forced to regard you as ignorant of the basic facts about the world.

[Obvious Leo]

Have you read David Deutsch's work on this subject?

[wtf]

Have you read David Deutsch's work on this subject?

No, but I should and I will. Also Tegmark.

[Arising_uk]

The inputs are not arbitrary. An evolutionary algorithm is completely deterministic but its determinism is immanent rather than transcendent. In other words the universe writes its own software.

Hmm...but if the inputs aren't arbitrary then it hints at a Great Programmer?

[Arising_uk]

No, but I should and I will. Also Tegmark.

Me too I think as I've been away from this stuff a while. Be nice to see where it's gone.

[Obvious Leo]

Have you read David Deutsch's work on this subject?

No, but I should and I will. Also Tegmark.

Max Tegmark is always a good read but he's an ever-moving target. Sometimes you think that he's onto something of great significance and then he seems to veer off onto some inscrutable mathematical tangent. I think he's one of these blokes that tries to hold too many ideas in his head at once and misses out on the big picture as a result. Brian Greene and Frank Wilcek are less imaginative but a bit more comprehensible. I tend to just poach different ideas from different people and then follow the advice of my sister-in-law who gave me this on a plaque to put above my desk:

"Just give me the FACTS. I can put in my own bullshit later."

[Obvious Leo]

The inputs are not arbitrary. An evolutionary algorithm is completely deterministic but its determinism is immanent rather than transcendent. In other words the universe writes its own software.

Hmm...but if the inputs aren't arbitrary then it hints at a Great Programmer?

I still think you're missing the significance of Conway's model when you say this. In a computational model of reality we can equate information and energy so we can think of the the little "bits" in Conway's representation as quanta of energy encoding for the subatomic particles at the Planck scale. Its a hell of a lot simpler than string theory because it needs no Great Programme. Conway's gliders self-organise into progressively more complex structures in an embedded hierarchy of informational complexity and in order to do this they need no over-arching law beyond the law that all effects must be preceded by a cause. The total entropy of the universe ever since the big bang has therefore been steadily decreasing as a result because new information is being generated in these emergent hierarchies. This is impossible in a programmed reality so we mustn't think of the cosmic computer as a computer which is executing a programme but rather as one which is programming itself. It quite literally makes it up as it goes along and a very easily understood example is solar system formation. I'd be willing to bet that in the entire universe there are no two solar systems which are identical because the number of different ways in which such structures can form is practically infinite. Not literally infinite but near enough as makes little difference and certainly near enough to put the idea of the "laws of physics" to the sword. The real world is the world of "shit happens" but this doesn't mean it happens without a cause. it just means it happens without a plan.