BlackSails wrote:Ok, now it just sounds you are quoting from timecube, or what the !@#$%^ do we know anyway.
Quoting from knowledge, but you can also check Wikipedia if you wish. Quantum article.
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BlackSails wrote:Ok, now it just sounds you are quoting from timecube, or what the !@#$%^ do we know anyway.
Kyrn wrote:BlackSails wrote:Ok, now it just sounds you are quoting from timecube, or what the !@#$%^ do we know anyway.
Quoting from knowledge, but you can also check Wikipedia if you wish. Quantum article.
BlackSails wrote:Kyrn wrote:BlackSails wrote:Ok, now it just sounds you are quoting from timecube, or what the !@#$%^ do we know anyway.
Quoting from knowledge, but you can also check Wikipedia if you wish. Quantum article.
Knowledge, really? Then you must know all about how photons are just excited modes of a spin 1 quantum field.
And wtf does "Photons are the lowest quanta a "piece" of light can be" even mean?
BlackSails wrote:Sure you can. Its very easy in fact. http://en.wikipedia.org/wiki/Spontaneou ... conversion
Photon number isnt conserved.
doogly wrote:Variance wrote:Quantum Physics describes probability distributions that are a result of imperfect observation at the atomic and subatomic levels
No, this is an extremely essential point. Quantum mechanics is not about *our* uncertainty, it is about the *universe's* uncertainty and indeterminancy. You can distinguish between these things a la Bell.
Kyrn wrote:Wrong, entropy describes the fate of the system at all points in time; Given any interaction or changes of state, the resultant state should always have less potential energy/information (depending on which Entropy theory you're referring to here). If there is an experiment which shows otherwise, either the experiment is misintepreted, the theory is wrong, or our understanding of how the theory should be applied is wrong, period (this however doesn't necessarily make it useless, just as newton's laws aren't useless even though it's been proven wrong). This is precisely why information theory is more commonly used (because it handles statistical variations), though in my opinion, the conventional entrophy theory will give the same results if you consider wave functions as opposed to discrete values. Technically, it would make the conventional theory statistical in nature as well, but it would allow the theory to apply to energy as well as information.
Um? Information theory states that entropy is a scale dependant thing. Things that are highly ordered, if left to jostle, will more likely become less ordered -- but things that are highly disordered, if left to jostile, will eventually become highly ordered.
Your second statement acts only in the finite basis. See above. Whatever a system does in a finite period of time is irrelevant in any conception of entropy, as probability allows for plenty of temporary increases in complexity. It's only the ultimate fate of the system that is important.
Both wrong. First, you're simplifying far too much. Information theory is about how much information one can determine from a system. For that matter, unlike thermodynamics, Information theory can be applied to a non-finite system, for the simple reason that it has no direct bearing to physics or the real world (It's maths). Furthermore, thermodynamics would be a subset of theories that can be derived from information theory; you simply cannot assume that any non-limitations on information theory is automatically applicable to thermodynamics.
To simplify the relationship with both, information entrophy is the amount of information you can gather from the current state. The more you attempt to gather information or otherwise change the environment, the more entrophy increases, up to a point where no more information can possibly be gathered about the initial system. Coincidently this is the same point where thermodynamic entrophy peaks, because the energy potential of the system is in itself also part of the potential information that can be gathered (or in my opinion, the whole of the information that can be gathered, if one considers energy states as opposed to discrete energy potential; the states in itself is actually a form of calculation of available/known information).
For further information, the maxwell demon thought experiment gives a theoretical example of how information entropy and thermodynamic entropy are linked.
We were obviously wrong then in the previous definition of light. A=A and A=!(not A), though, are based on far simpler observations and cannot be "incorrect" in the way that more complex observations can. While you can find your definition of light is wrong, you cannot "find" that A is actually B unless it spontaneously changes nature, which never happens. The observations are too axiomatic to be able to be incorrect. But again, this is all beside the point that I was making, which was that A=A are also observations, so although they could *theoretically* be incorrect, somehow, they are much less likely to be incorrect than the statement that "the laws of thermodynamics were violated", which does not have as much evidence supporting it. And since the statements are at odds, one must be wrong, and I posit that the probability rests with the latter being wrong.Unfortunately, ALL of our current understanding of the world (aka science) is dependant on A=A and A!=(not A). But the more imporant question is, what is A to start off with? Place a wrong definition, and naturally all your equations wouldn't give the correct result. For instance, if one were to assume that light are made of waves, they would have given the wrong definition to light, and hence lead to flaws in calculations.
And supernatural beings, though nice, does not help with understanding at all, because we can make no further conclusions from it. As far as possible, one must strive to derive a set of rules which can explain the world, as far as science is concerned, so as to be able to make conclusions from such. The only time I accept supernatural beings in my theories is when there is no further use for conclusions or there can be no further way to form conclusions, but we are far from that as far as quantum dynamics are concerned.
For note, I don't mind a supernatural being be the cause of the universe since there is no point trying to figure out what happened before time. But they have no place from the very point time (and our universe) began, except for a few instances where we cannot suitably explain or solve by science alone.
BlackSails wrote:Variance wrote:Essentially, two repelling bodies right next to each other would generate opposing force and direct their momentum away from each other, but as their real momentum decreases, their momentum potential increases. There is no differentiation between the two in Conservation of momentum, so the sum of the real momentum and potential momentum remains constant.
Uh no, there is no such thing as "momentum potential"
Variance wrote:I can't say much here beyond that you're wrong. Let me explain the philosophical basis:
The universe cannot be said to have any nature but that which we observe. I think it exists independent of observation, but that's beside the point: the only things we can say about it are those we observe.
Variance wrote:We cannot observe things at the quantum level well enough to tell exactly where or how things are, a la the Heisenberg Uncertainty principle. This does not mean that the things themselves have any probabilities attached to them.
Variance wrote:The universe cannot be said to have any nature but that which we observe. I think it exists independent of observation, but that's beside the point: the only things we can say about it are those we observe.
We cannot observe things at the quantum level well enough to tell exactly where or how things are, a la the Heisenberg Uncertainty principle. This does not mean that the things themselves have any probabilities attached to them. This is important: quantum mechanics ascribes no probabilities to things that are brought out of anything but our own inability to effectively observe these processes.
I make no claims as to whether there are actually any random properties to the processes that happen in the universe. Neither does quantum mechanics. Because we don't know, there's no reason to positively assume that there are probabilities that act in these processes in reality; this is derived from the basis of Burden of Proof. We only know that we can't observe the processes well, and that this introduces probabilities into our perception of the universe.
We cannot say, nor is there any outstanding evidence that I know of, that there is any probability in the universe in actuality. There is only the probability in our perception, which is as good as any. It's all semantics, but it's important to understand when considering the philosophy behind the workings of the universe.
BlackSails wrote:A particle simply does not have well defined values of observables until we actually observe it and collapse the wavefunction. Its not that we dont know it. Its that it does not exist.
doogly wrote:Man, if we get stuck with nonlocality, I am quitting. Better to have been a shoemaker.
telcontar42 wrote:I know there may be some theories to the contrary, but as I understand it, it is well accepted that quantum mechanics is not based on hidden variables, as proved by Bell's inequality.
SpazzyMcGee wrote:sinc wrote:so, is the only natural possibility is for there to be nothing at all?
Nothing by definition doesn't exist.If IT existed then it wouldn't be nothing.
BlackSails wrote:Thermodynamics is information theory. You can argue this point, but you would be wrong.

Indon wrote:SpazzyMcGee wrote:sinc wrote:so, is the only natural possibility is for there to be nothing at all?
Nothing by definition doesn't exist.If IT existed then it wouldn't be nothing.
Unless it was explicitly defined as being nothing.
[/quote]If, for the sake of argument, you assume that the universe is ultimately a logical construct of some form (and since this discussion is skimming theology anyway, why not assume it?), then it is equally natural for the universe to be nothing as it is for it to be something.BlackSails wrote:Thermodynamics is information theory. You can argue this point, but you would be wrong.
Wouldn't thermodynamics concern a part of information theory, and information theory concern a part of thermodynamics?
That is to say, thermodynamics also concerns things that have nothing to do with information and information theory isn't all about heat.
Kyrn wrote:Leave computer science out of this. Computer science is not reality.
Kyrn wrote:Leave computer science out of this. Computer science is not reality.
Kyrn wrote:(and the null pointer doesn't mean nothing to begin with. If we consider computer instructions as a language, null pointers means the WORD undefined, not any actual value. The only thing that means nothing is the representation of 0 (or 0 bit, or false, which all means the same thing in code)
Kyrn wrote:Energy quantity is a fraction of Information. Other subsets of information includes positional, temporal (arguably same as positional depending on PoV), directional. There is nothing in thermodynamics which is not part of information theory, but there are plenty in information theory which is not part of thermodynamics. Or to simplify, Thermodynamics is a subset of Information.

Indon wrote:Thermodynamics is a subset of physics. Information theory broadly applies multiple fields of physics for a specific purpose, but I wouldn't describe it as co-opting any of them in that sense.
Kyrn wrote:I will admit I cannot suitably (explain/visualize/understand) my point, and that my knowledge isn't complete (again, not a quantum scientist).

Indon wrote:To continue the 'reality is strange' point Yakk has been working on, we don't know that.
Uh, no. Null is the concept of nothing, and is expressed at a higher logical level than bits. When an object is null, the null denotes that the object correlates to nothing - that it is a descriptor of and for nothing. A null object isn't simply the lack of something - it is the lack of everything, a non-thing, in a sense. An undefined object is an object which isn't anything - thus... nothing. I can go on.
0, as a bit, is simply off - that level of abstraction does not effectively describe the concept of 'nothing', as a bit set to 0 is a thing that you can manipulate extensively. You can't manipulate nothing - you can only verify that it is, in fact, nothing.
Azrael wrote:Guess what? I'm going to pick on you! This is a prime example of when you shouldn't be posting in SB. Do your homework, cite your assertions and know what you're talking about before opening your mouth.
Take a break from the thread.
Kyrn wrote:Indon wrote:To continue the 'reality is strange' point Yakk has been working on, we don't know that.
The biggest difference between computer science and reality as we know it, is because we defined the rules of computer science, starting from all interactions involving only two states. In a sense, computer science starts from the definition, then we create the world, science has the world created, and then we attempt to define it.
Kyrn wrote:Take for example: if quantum computing really takes off, be prepared to see computer science being split into two distinctively separate languages, simply because the "undefined" would greatly change the whole landscape. We no longer have to work with the assumption that everything is either true or false. The "=" symbol would have to be completely rethought.Azrael wrote:Guess what? I'm going to pick on you! This is a prime example of when you shouldn't be posting in SB. Do your homework, cite your assertions and know what you're talking about before opening your mouth.
doogly wrote:Kyrn wrote:Take for example: if quantum computing really takes off, be prepared to see computer science being split into two distinctively separate languages, simply because the "undefined" would greatly change the whole landscape. We no longer have to work with the assumption that everything is either true or false. The "=" symbol would have to be completely rethought.Azrael wrote:Guess what? I'm going to pick on you! This is a prime example of when you shouldn't be posting in SB. Do your homework, cite your assertions and know what you're talking about before opening your mouth.
Azrael's words are relevant a second time!
= does not mean something completely different. Quantum mechanics does not change how logic works, just how probability works. You should check out the quantum computing stuff Scott Aaronson put up, which Blacksails mentioned. It's extremely good.
Kyrn wrote:I never said it means anything different, but it has to be rethought. I admit I wasn't clear on what "=" meant, but it applies to both cases.
Equality has always been consistently used for determination of whether a statement is true or false in terms of computer sciences, and is not compatible with undefined/probability values. To put simply, if X is a quantum value and Y is a quantum value, X EQUALS Y will no longer return either true or false.
Assignment would have the same issue: if X (quantum value) is assigned to Y, X is not necessarily equal to Y (no local hidden variables).
Let's all remember that when I tell you to leave a discussion, there are consequences if you don't.Kyrn wrote: Stepping out.[/EDIT]

According to classical physics, yes. According to quantum physics, apparently no.MrGee wrote:Also, wouldn't a proton pendulum release energy in the form of gravity waves and eventually halt?
doogly wrote:Is this a known result somewhere?
Variance wrote:We cannot observe things at the quantum level well enough to tell exactly where or how things are, a la the Heisenberg Uncertainty principle. This does not mean that the things themselves have any probabilities attached to them. This is important: quantum mechanics ascribes no probabilities to things that are brought out of anything but our own inability to effectively observe these processes.
Kyrn wrote:Citation please: Basically, as far as I know, any experiment which seems to reduce entropy, indirectly increases entropy in a different locale by an equal or greater manner. I would like to know what proves otherwise.
Yakk wrote:
Bell's Inequality and that really neat other theorem -- I swear someone linked it in this thread?!
BlackSails wrote:Variance wrote:I can't say much here beyond that you're wrong. Let me explain the philosophical basis:
The universe cannot be said to have any nature but that which we observe. I think it exists independent of observation, but that's beside the point: the only things we can say about it are those we observe.
Quantum mechanics makes testable predictions about things that did not occur. For example, take the Elitzur-Vaidman bomb tester.
The basic set up is this: You have bunch of bombs. Each bomb detonates when it detects a photon. Some of the bombs are duds. How can you distinguish the duds from the real bombs?
The obvious answer is you try to detonate them all. The ones that dont explode are the duds. But what if you dont want to explode them?
To do that, you can set up an apparatus called a Mach Inferometer, and using that, you can determine if a bomb would have exploded had a photon hit it. Obviously though, since it doesnt explode, the photon doesnt hit it.
You can also do the same thing with spins (this is basically Bell's theorem). You have a particle, it decays into an electron and positron. If you measure the spin on the electron, you know what the spin is on the positron, despite never measuring it.
doogly wrote:Variance wrote:We cannot observe things at the quantum level well enough to tell exactly where or how things are, a la the Heisenberg Uncertainty principle. This does not mean that the things themselves have any probabilities attached to them.
Heisenberg Uncertainty Principle has nothing to do with measurement. It is a straightforward consequence of the fact that momentum is the Fourier transform of position. This happens in signal processing as well - do you think spectral broadening is a result of observer ignorance, or nature?
And Bell is really a principal scenario in which to notice the difference. What is your scientific background? There are explanations of this effect at a variety of levels I can point you towards.
BlackSails wrote:Indon wrote:Thermodynamics is a subset of physics. Information theory broadly applies multiple fields of physics for a specific purpose, but I wouldn't describe it as co-opting any of them in that sense.
Thermodynamics is a subset of information theory, just like kinematics is a subset of mechanics.
Edit: And if you believe wheeler, all physics is a subset of information theory
MrGee wrote:Also, wouldn't a proton pendulum release energy in the form of gravity waves and eventually halt?
Bell's Inequality and that really neat other theorem -- I swear someone linked it in this thread?! -- show that naive local realism with measurement problems cannot be what is going on behind quantum mechanics. And apparently we have cut down the possible "hidden variable" theories even further -- saying "physics is non-local" isn't enough to allow you to inject hidden variables and wipe your hands of quantum wierdness!
Reality is weird. Attempting to make teleological arguments based on human-scale every-day experience about the universe isn't a really strong argument, in my mind: because when we look at the universe on scales away from ours, we get crazy things all over the place.
doogly wrote:I'd like to avoid arguing from authority, I'd rather argue from physics. This is why I'm trying to determine how much you know, and if you tell me where you are at, I can address you at that point. Can you do the chapter in Sakurai that covers this? I think Griffiths QM also has a section it, that is undergrad level. If you don't know any quantum mechanics at all, I am going to talk from an authority position, sorry.
Gravitons aren't part of the Standard Model. And in the standard model, fundamental particles do decay. Muons are not composite, but an energetic one can definitely decay.
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