There are a few physicists that propose that the universe is a hypercomputer. One example is Roger Penrose, who, basing in his quantum interpretation () and in spin networks (), proposes that the universe is basically a giant hypercomputer.  But, since that universe would contain completely uncomputable things, doesn't that mean that these models don't assume computability? I mean, wouldn't that mean that literally every uncomputable thing could happen in these hypercomputer-universes? Even things that could not be "computed" by a hypercomputer?  In that case, then, is it possible to mathematically define a hypercomputer-universe where even things that could not be computed by that hypercomputer would exist? And if yes, wouldn't be the case that if we introduced/defined a trivialist system () in this hypercomputer-universe model (to produce/create or "simulate" a trivialist universe, or any other class of impossible world ()), then, every illogical/logically impossible things, even those illogical/logically impossible things could not be computed by a hypercomputer because they are logcially impossible or simply impossible to describe/conceive/compute, would certainly exist (in this hypercomputer-universe)?
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There are things which are illogical/logically impossible (like saying that 2+2=4 and 2+2=5. Without changing anything in the axioms of mathematics or logic, this would be a contradiction and would be inconsistent and illogical/logically impossible.   There are other types of logic systems apart from classical logic, like paraconsistent logics or even trivialism, that allow these contradictions to occur, prove them as right and work with them.   We can make a paraconsistent or trivialist system and work with it. For example, with trivialism, in theory, we would be able to derive and state everything we would want (since literally everything, even including illogical/logically impossible inconsistencies and contradictions), but we as humans (or as brains), are limited and can't conceive everything we want (at least to what I know). Therefore, no matter how many trivialist models we create and how much time we would work with them, we would never find or conceive many illogical/logically things because they are just that: impossible. There are impossible things to describe and conceive. For example, Russel's set is the set of all sets that do not contain themselves. If Russel's set contains itself, then it cannot contain itself, since it only contains sets that don't contain themselves. But if Russel's set does not contain itself, then it must contain itself, since it contains all sets that don't contain themselves.  There are quite a few logic bombs like this. You cannot ever compute the contents of Russel's set, and there are more formal, mathematical ways to present it. All of them have in common that you can't actually compute what the set is, whether you do it by hand, in your head, or on a computer. It's just a statement that cannot be fully logically processed.  If you take every possible state the human brain can be in, none of them include the computation of Russel's Set's contents. That is, not only can the contents not be computed, they cannot even be represented. No stimulus can cause us to comprehend Russel's Set, since such comprehension is not possible to begin with. It does not have a solution. Even if we try to solve it using trivialism, we would just be able to write a solution that does not make sense and prove it has sense and it is the real solution, but we could not be able to have a solution that would make sense "outside" the realm of trivialism (for example in classical logic), even though, using trivialism, we could prove that such solution would have sense in whatever context and logic system.   But what about hypercomputational machines (for example oracle-like machines)? I've read about some models of hypercomputation which are compatible with paraconsistent or trivialism logics. I've also read there are some models of hypercomputation (particularly those oracle-like models which use a black box) where, essentially, the hypercomputer is an algorithm that cannot exist. It might be because such an algorithm is fundamentally forbidden by logic itself (which is hided in a black box). Would any of these be capable of computing/"conceiving" these impossible things I wrote before? Do you know of anything that would help?
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What is currently stopping us from having a theory of everything? i.e. what mathematical barriers, or others, are stopping us from unifying GR and QM? I have read that string theory is a means to unify both, so in this case, is it a lack of evidence stopping us, but is the theory mathematically sound?
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It is well known that the probability of life arising in a universe of our sort is vanishingly small. Theists have used this fact to argue that life is designed by God. However, if there are an infinite number of parallel universes as part of a  such as , then even that very infinitesimal probability seems to compel the existence of life as a necessary truth. If one is justified in invoking an infinite number of parallel universes, even the most unlikely event must occur in one particular universe. This argument seems to mirror race conditions among infinities and infinitesimals. So, if conventional statistical reasoning is applied, doesn't this obviate mathematically ? What is the current state of philosophical arguments in quantum physics and natural theology in regards to the collision of these two theories?
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There didn't exist computers.      Will there happen similar events in the future?   Are these sentences grammatical or is my mind making stuff up? I haven't been able to find much on the net.
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Does String theory say that spacetime is not fundamental but should be considered an emergent phenomenon?  If so, can quantum mechanics describe the universe at high energies where there is no spacetime?  Schrodinger equation assumes the presence of time dimension. So how can such equations be valid at extremely high energy?  And is it meaningful to do physics if there is no time dimension?  Would the concepts of Hilbert space, wavefunction collapse etc be useful in that case?
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I am assuming there are two constituents that obliterate our current model of physics;   that it's infinitely dense that it's infinitely small   Please correct me if I am wrong.
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It is well known that quantum mechanics and (general) relativity do not fit well. I am wondering whether it is possible to make a list of contradictions or problems between them?  E.g. relativity theory uses a space-time continuum, while quantum theory uses discrete states.  I am not merely looking for a solution or rebuttal of such opposites, more for a survey of the field out of interest.
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I would like to know if anyone knows the word for something that should be impossible but has happened. An example is the Big Bang Theory. It shouldn't have been possible but something happened for us to exist.
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I'm a layman, but i watched some intereting videos about big bang on youtube[michio kaku, hawking this kind of things, not some crackpots :)]   I described everything on my picture:     So is there any possibility to see that inner side, for example, by creating wormhole, or entering new dimension? Or i get something wrong, on the way, and my model is totally wrong?  And another question. I heard that even if you would fly a ship across the universe you would eventually end in the place where you started, because we live in a 3d space that is defined on a surface of big sphere. But why a big sphere? Universe might be a big mobius strip, and the same principle of ending at start will apply. Is it possible?  Thanks in advance, and please don't bash me for silly questions. Im just curious, but i don't have any degree in physics. Im also not an english native speaker.
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I have recently been thinking a lot about determinism and pretty much decided there was no reason to refute it as there was no evidence of free will that I could find. However, a couple of days ago, this thought experiment came to me and it seems to be a point against determinism so I wanted to see what the SE thought:   Assume that in a few years, someone finally built the determinism computer that took every variable into account and could therefore predict the next action of everything, (including people assuming there is no free will). So I print out the page of Mr Jack Robert and it happens to say he will eat cereal in exactly one hour. In an effort to prove free will, I run over to his house and pay him 100$ to eat salami instead.   By this type of line of though, as long as I knew what the computer predicts, I should be able to do something different than what it asserts I will do every-time and quite literally make it impossible for it to make the right prediction, something impossible if there was only determinism.  Is this a good case against determinism?
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I've always hit two big stumbling blocks in conceiving of the proof or disproof of  as being even valid idea, let alone an answerable question... I feel I must be misunderstanding some very fundamental things.   Quantum mechanics is deterministic, ignoring the bit where we take our complex number and fudge it into a probability. We use computers to make calculations to provide the predictions of quantum mechanics - how is this not itself a hidden variable theory?   From what I understand the famous Bell theorem and work around it doesn't disprove hidden variable theories, just one specific flavour of them, and even then I am not convinced. I feel like I must be missing something again, because this result seems to me in no way profound... although it certainly fits into the picture of the EPR 'paradox' and is a good demonstration of the validity of QM.  I guess the crux of my problem is that this 'area' really addresses wave function collapse and the problems it causes, but I don't see the need for some collapse mechanism to begin with... again I feel like I am missing something really fundamental.  Apologies if this is a bad question. I have had a look around and there are similar questions, but I don't feel that either of my points are addressed...
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Possible Duplicate:          I've heard of De Broglie–Bohm theory a.k.a causal interpretation of quantum theory. The predictions match accurately with with the nondeterministic quantum theory.  As a philosophy buff this one seems just like the classical universe. No funny new-age religion style gimmicks.  So why don't people use this interpretation instead of the Copenhagen "magic" interpretation?  P.S. I'm not an expert. I possess only superficial knowledge of quantum physics.
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Quantum computers are known to be able to crack  a broad range of cryptographic algorithms which were previously thought to be solvable only by resources increasing exponentially with the bit size of the key. An example for that is .  But, as far I know, not all problems fall into this category. On , we can read     Researchers have developed a computer algorithm that doesn’t solve problems but instead creates them for the purpose of evaluating quantum computers.   Can we still expect a new cryptographic algorithm which will be hard to crack using even a quantum computer? For clarity: the question refers to specifically to the design of new algorithms.
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I saw  hosted by Stephen Hawkins.  And if I didn't get it wrong, it says that there was no time before the big bang, time was created there.  So how can anything happen when there is no time (eg: the creation of time and the universe)? Is this what he calls a 'singularity'? Which I could think like this: when there is no time nothing can happen, except during this singularity.  Of course I don't know of a law that says 'when there is no time nothing can happen..', I just came up with it, as something intuitive.
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If the theory of everything indicates a singularity-free and finite universe, will  be relevant to the universe? If so, is there any interesting physical consequence, e.g. in superstring or quantum gravity?
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I have seen approaches at building hyperreal systems by using complicated notions like ultrafilters and the like.  Why not just postulate the existence of infinitesimal element $\varepsilon$ and infinite $\omega=1/\varepsilon$ like we do with complex numbers and build a field system around them?
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Maybe this is a silly question (I think it is), but it's a question I'm arguing with some of my friends for a long time.  The ultimate question is: Is everything (in our Universe) possible ?  I've read some books (Penrose, Hawking, Greene, etc.) where it was clearly stated several times that quantum mechanics allows any situation to happen (e.g. everything is possible) - even with absurdly tiny probabilities?  Does this mean only physically possible - or "ultimate" possible ?  For example (I know this example seems really absurd, but I'm saying this so you get the idea) what my friends clame it is possible:   If I ask my friend(s): "Is it possible there is a Sun-sized star in my pocket right now?" They will respond: "Yes, there is very very tiny possibility this can be true!" Etc.