Quantum Mechanics
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I am 1 graduate course away from a phd in Quantum Mechanics.... Dictionary.com says: ran⋅dom /ˈrændəm/ Show Spelled Pronunciation [ran-duhm] Show IPA –adjective 1. proceeding, made, or occurring without definite aim, reason, or pattern: the random selection of numbers. 2. Statistics. of or characterizing a process of selection in which each item of a set has an equal probability of being chosen. o.k. in order: :doh: 1; quantum particles behave according to their "nature" they usually are "aimed" (at the lowest local energy state), the reason is entropy(usually) and they have a pattern(albeit poorly defined: See Heisenberg uncertenty principle.. which basically says that if a particle is then it exists somewhere in the universe, but you will never know where it is... ) 2; the positions of any given quantum particle can never be know, however it is to all reasonable approximations residing in bounding frustrum in space-time(its physical extent..from a certain perspective). However the exact probability that a quantum particle is ever in any position is 0 (i.e. it doesn't exist). [Check this out^] so to answer your debate: (if you believe in string theory and that there exists a grand unified field theory) everything in the universe is pre-determined by something that is so complicated that we percieve it as random, although were we capable of peering into an alternate dimension we could (knowing absolutely EVERYTHING) possibly account for all particles(assuming that that universe exists of only one sub atomic particle.. (n=9)^27 after that (n=81)^27 the calculation becomes .... unstable or simply to big to compute... but even if you could compute it it wouldn't matter because that universe would have already cooled and you would need to recompute the answer... (if you only go to quantum theory) then yes there is randomness in this universe (below the quantuum classical barrior aproxamatly less then 200 microns ) (if you believe that newton was the last scientist ever) then no there is no randomness. your finite machine depend on scale if it's "pointer" is >200 microns your friend is absolutely correct(sorta) if your below the threshold but still greater then one particle(in a universe)
Really? I thought the basic axioms of quantum measurement pretty much stated that measurement is a random process.
I can imagine the sinking feeling one would have after ordering my book, only to find a laughably ridiculous theory with demented logic once the book arrives - Mark McCutcheon
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This place seems to be full of computer scientists... The point of view of many responses assumes an ACTUAL point of view: some tool, person or other physical object to actually witness the event. The fact of the matter is, that none of us, nor any tool we can make, can measure every atom at every given time, so one needs to step out of the box that is science. I am not talking religion (definitely not!), but quantum mechanics is a scientific notion, and science is itself a man-made concept, so the only way we can measure anything as a result of a discussion around it, is by using man-made restrictions. To truly understand, we must put aside what we know about time and space and matter because absolutely everything we base our present and future understandings on is from past definitions of measurements that scientists needed to make up in order to provide an answer to their question. If we could truly step back and witness things from a distance, we wouldn't be interacting with the environment, we would, in communicable terms, actually no longer exist... I love the philosophical debate around predeterminism, because it shows us as humans, really have no clue :)
And, in not existing, we would no longer be able to observe, thus losing the ability to 'step back and witness things'. Bringing God into it, God does not lie, and His creation expresses QM down to its very essence, as far as we can see, and as far as we are even able to conjecture. You can go ahead and throw out all thinking and measuring that has ever been done, up to this point, but, even within your argument, it does not buy you anything. We measure thing the way we do, because we have a limited set of sensors - we sense change in pressures (sound, touch) a limited band of the EM spectrum and some chemical receptors. We translate those to sight, touch, hearing, taste/smell and some temperature. Unless you think that you have more insight than all of previous humanity, put together, you are, at best, going to just walk your way through human discovery, making the same mistakes that have been made historically. After 50 to 70 years of discovery, you will die, having moved your way up to classical physics, and maybe have dim view of QM, if you are truly brilliant. But mu guess is that you would have not gotten that far, since our senses are prone to making us make the same mistakes that were made in the historical analysis of the world. "If I have seen further it is only by standing on the shoulders of Giants." Newton realized this 430+ years ago. Are you smarter than him?
Silver member by constant and unflinching longevity.
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And, in not existing, we would no longer be able to observe, thus losing the ability to 'step back and witness things'. Bringing God into it, God does not lie, and His creation expresses QM down to its very essence, as far as we can see, and as far as we are even able to conjecture. You can go ahead and throw out all thinking and measuring that has ever been done, up to this point, but, even within your argument, it does not buy you anything. We measure thing the way we do, because we have a limited set of sensors - we sense change in pressures (sound, touch) a limited band of the EM spectrum and some chemical receptors. We translate those to sight, touch, hearing, taste/smell and some temperature. Unless you think that you have more insight than all of previous humanity, put together, you are, at best, going to just walk your way through human discovery, making the same mistakes that have been made historically. After 50 to 70 years of discovery, you will die, having moved your way up to classical physics, and maybe have dim view of QM, if you are truly brilliant. But mu guess is that you would have not gotten that far, since our senses are prone to making us make the same mistakes that were made in the historical analysis of the world. "If I have seen further it is only by standing on the shoulders of Giants." Newton realized this 430+ years ago. Are you smarter than him?
Silver member by constant and unflinching longevity.
In the scientific definition of not existing, yes, that is fundamentally true... It's not about having insight, it's about thinking about things in a different way. Don't get me wrong, I have a very mathematical mind, and I like that science can explain much of the world today. My point really was that, we can't prove or disprove predeterminism with quantifiable measurements based on modern day science - just like scientists of old used to do: we need to look toward philosophy. Imagining yourself in the shoes of someone viewing the changing world still results in human restrictions (which is anything finite - clearly the universe doesn't obey any rules of finity!)Step beyond existence, and you are in the realm of philosophy, where argument can lead to scientific discovery.
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achimera wrote:
the uncertain portion would lead to "randomness"
I don't think that that is correct. Being uncertain about the properties something does not correlate to its being, or behaving, randomly. It is entirely possible that its behaviour is pre-determined, although I personally don't think so, but it appears to be random because of our inability to fully understand the forces acting on it.
Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”
It's not just uncertain, it's "information not actually in existence". Observation changes the observed, it's one of the most perplexing points of QM. It's not just that the act of observation disturbs the particles in question because we're big dumb monkeys playing with tiny things. Even large enough groups of atoms become self observant, (Not self aware, just self observant). Try not to consider the whole observation thing for too long though. PETA gets upset about contraptions involving cats and radio-active materials.
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At what point does unpredictable determinsim become randomness?
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In the scientific definition of not existing, yes, that is fundamentally true... It's not about having insight, it's about thinking about things in a different way. Don't get me wrong, I have a very mathematical mind, and I like that science can explain much of the world today. My point really was that, we can't prove or disprove predeterminism with quantifiable measurements based on modern day science - just like scientists of old used to do: we need to look toward philosophy. Imagining yourself in the shoes of someone viewing the changing world still results in human restrictions (which is anything finite - clearly the universe doesn't obey any rules of finity!)Step beyond existence, and you are in the realm of philosophy, where argument can lead to scientific discovery.
I agree that you can not prove, or disprove, predetermination with 'modern day science'. We have available to us certain types of knowledge, and none of those seem to be enough for us to understand why the wave function collapses. Once we know enough to really say that we understand why it collapses the way it does, and correctly predict that the way it will collapse in the future, we have, in essence, proved predetermination. But every indication we have now is that there is no extra underlying information there for us to find. If we prove that, we have 'disproved' determinism. As far as 'philosophy' vs 'science', I think you are looking with a prejudiced eye: If I understand your description, philosophy is thinking things out, not being constrained by current dogma (dogma is different from 'science'). QM, relativity, even classical physics result from thinking things out, unconstrained by current dogma. Yet they are 'science', even if they are also philosophy. So, I think that you are short changing 'science' by making it a limited activity, and implying that it does not include 'philosophy'. Also, I don't think that you can actually prove or disprove, something with philosophy. You can think hard about it, but, short of experimental evidence, you have only come up with a thesis, a theory, that than requires proof or disproof in the real world. Otherwise you are just arguing about how many angels can dance on the head of a pin. Albert Einstein, Neils Bohr, Werner Heisenberg, Isaac Newton, Thag Simmons*, all those folks who came up with every theory, going back to 'the day'(thousands of years ago) that explains the world, have to submit their ideas to the razor of predicting results and getting consistent answers. That is one reason a lot of people don't yet believe string theory - it doesn't yet predict anything that is different from what our current models predict (at least the most successful, the less successful do not even correctly predict things we know are reality). "clearly the universe doesn't obey any rules of finity" What does this mean? I am asking to find out, I am not belittling, but trying to understand. *Thag is well know for coming up with the theory, which he than proved (at the cost of his life) that getting pounded by a Stegosauria tail can hurt you (see thagomizer[^])
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Really? I thought the basic axioms of quantum measurement pretty much stated that measurement is a random process.
I can imagine the sinking feeling one would have after ordering my book, only to find a laughably ridiculous theory with demented logic once the book arrives - Mark McCutcheon
Only if your looking down on it (from a Newtonian path length), if your looking up at it (from the scale of string theory) that is not correct(if you believe that there exists a Grand Unified Theory ) but your not looking at the information theoretic perspective... if you know that there is something there to measure, a measurement has already been made, and as such nothing which happens afterwords is random... until that is you "forget" the information and then it may.. MAY act in a "random" manor.. but this is more of semantics.. Eurandom numbers are essentially theoretical the best we can hope for is a good pseudorandom number generator^. Yes there are those that offer isotopically derived RNG's^ However they only work on a non-geologic time scale.. not on the cosmological time scale(again the issue or scale). The quality of the random number will always tend to "decay" sorry the pun until it approximates a steady state.. So there is a pattern, albeit poorly defined. The issue is that the entropy involved in "knowing" a random number cools the universe, and as a result the number is no longer Eurandom because the universe had to cool a certain amount to get it.. but yes you are correct in that to take the information from the universe to get the measurement, you have changed the object being measured, but that value is not random it is a finite slice(at time t) from an infinity dimensional space ( t one of the dimensions) . however you cannot control which dimensions you are sampling from... were you argument correct (as stated) we couldn't target a buckminister fullerene(which obviously we can) in an Atomic Force Microscope^ because they can be considered quantum particle (from a certain perspective)see quantum mechanics heading at wikipedia^. we can also target electrons, however we can't say which electron we are targeting due to degeneracy, however we can say that we are targeting the UP electon "here" and do it without getting the DOWN electron over there (unless we are trying to see quantum teleportation in Nature physics^(yes a reputable
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Only if your looking down on it (from a Newtonian path length), if your looking up at it (from the scale of string theory) that is not correct(if you believe that there exists a Grand Unified Theory ) but your not looking at the information theoretic perspective... if you know that there is something there to measure, a measurement has already been made, and as such nothing which happens afterwords is random... until that is you "forget" the information and then it may.. MAY act in a "random" manor.. but this is more of semantics.. Eurandom numbers are essentially theoretical the best we can hope for is a good pseudorandom number generator^. Yes there are those that offer isotopically derived RNG's^ However they only work on a non-geologic time scale.. not on the cosmological time scale(again the issue or scale). The quality of the random number will always tend to "decay" sorry the pun until it approximates a steady state.. So there is a pattern, albeit poorly defined. The issue is that the entropy involved in "knowing" a random number cools the universe, and as a result the number is no longer Eurandom because the universe had to cool a certain amount to get it.. but yes you are correct in that to take the information from the universe to get the measurement, you have changed the object being measured, but that value is not random it is a finite slice(at time t) from an infinity dimensional space ( t one of the dimensions) . however you cannot control which dimensions you are sampling from... were you argument correct (as stated) we couldn't target a buckminister fullerene(which obviously we can) in an Atomic Force Microscope^ because they can be considered quantum particle (from a certain perspective)see quantum mechanics heading at wikipedia^. we can also target electrons, however we can't say which electron we are targeting due to degeneracy, however we can say that we are targeting the UP electon "here" and do it without getting the DOWN electron over there (unless we are trying to see quantum teleportation in Nature physics^(yes a reputable
Most of what you posted doesn't even apply to the issue I'm bringing up. As I understand it, garden variety quantum mechanics measurement works like this. Given a wave function phi, the probability of observing it it in state theta is |< phi | theta >|2 end of story. It's got nothing to do with perturbing the object being measured, random number generators or any of that, it is just what taking a quantum measurement means. All the other stuff is about specific cases of the wave function. It's got nothing to do with the basic axioms of QM.
I can imagine the sinking feeling one would have after ordering my book, only to find a laughably ridiculous theory with demented logic once the book arrives - Mark McCutcheon
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Most of what you posted doesn't even apply to the issue I'm bringing up. As I understand it, garden variety quantum mechanics measurement works like this. Given a wave function phi, the probability of observing it it in state theta is |< phi | theta >|2 end of story. It's got nothing to do with perturbing the object being measured, random number generators or any of that, it is just what taking a quantum measurement means. All the other stuff is about specific cases of the wave function. It's got nothing to do with the basic axioms of QM.
I can imagine the sinking feeling one would have after ordering my book, only to find a laughably ridiculous theory with demented logic once the book arrives - Mark McCutcheon
I posted:
however you cannot control which dimensions you are sampling from...
as per you response
Andy Brummer wrote:
Most of what you posted doesn't even apply to the issue I'm bringing up. As I understand it, garden variety quantum mechanics measurement works like this. Given a wave function phi, the probability of observing it it in state theta is |< phi | theta >|2 end of story. It's got nothing to do with perturbing the object being measured, random number generators or any of that, it is just what taking a quantum measurement means. All the other stuff is about specific cases of the wave function. It's got nothing to do with the basic axioms of QM.
this is not a question of garden variety quantum mechanics. all measurements perturb. (see Feynmann above(he got a Nobel pertaining to the issue)) the "Axioms" (from wikipedia) Main article: Theory of incomplete measurements[^] The theory of incomplete measurements (TIM) derives the main axioms of quantum mechanics from properties of the physical processes that are acceptable measurements. In that interpretation: * wavefunctions collapse because we require measurements to give consistent and repeatable results. * wavefunctions are complex-valued because they represent a field of "found/not-found" probabilities. * eigenvalue equations are associated with symbolic values of measurements, which we often choose to be real numbers. The TIM is more than a simple interpretation of quantum mechanics, since in that theory, both general relativity and the traditional formalism of quantum mechanics are seen as approximations. However, it does give an interesting interpretation to quantum mechanics. -end wikipedia-- everything I said does in fact pertain because the original post was about a finite state machine(QIT) and the "axioms" above don't pertain to quantum information.. which
**is different then just simply measuring a wavefunction**. your "Hamiltonian" is not using the information about the finite state machine nor the entropy of the system (they don't teach this in undergrad courses) as a result you are using the wrong wavefunction -
Does not the physics of QM provide for "true randomness" in the Universe? I'm debating a friend who seems to think everything is predetermined, period. My argument against, is that his proposal would be a finite machine, one which could be moved either forward or back. Additionally, my argument continues, if true randomness exists, then it can't be predetermined nor undone. Am I incorrect? Any thoughts?
There are two possibilities: true randomness exists; only appears to be random. Truth is we can't know the answer. Just look at computer pseudo-random number generators: they take an initial value (seed), then produce a stream of apparently random numbers. Many random sources also don't *appear* random, like consecutively similar dice rolls. At the core of the universe, there could be true randomness or a glorified PRNG. Without access to the internals, there's no way we can determine which is correct.
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I agree that you can not prove, or disprove, predetermination with 'modern day science'. We have available to us certain types of knowledge, and none of those seem to be enough for us to understand why the wave function collapses. Once we know enough to really say that we understand why it collapses the way it does, and correctly predict that the way it will collapse in the future, we have, in essence, proved predetermination. But every indication we have now is that there is no extra underlying information there for us to find. If we prove that, we have 'disproved' determinism. As far as 'philosophy' vs 'science', I think you are looking with a prejudiced eye: If I understand your description, philosophy is thinking things out, not being constrained by current dogma (dogma is different from 'science'). QM, relativity, even classical physics result from thinking things out, unconstrained by current dogma. Yet they are 'science', even if they are also philosophy. So, I think that you are short changing 'science' by making it a limited activity, and implying that it does not include 'philosophy'. Also, I don't think that you can actually prove or disprove, something with philosophy. You can think hard about it, but, short of experimental evidence, you have only come up with a thesis, a theory, that than requires proof or disproof in the real world. Otherwise you are just arguing about how many angels can dance on the head of a pin. Albert Einstein, Neils Bohr, Werner Heisenberg, Isaac Newton, Thag Simmons*, all those folks who came up with every theory, going back to 'the day'(thousands of years ago) that explains the world, have to submit their ideas to the razor of predicting results and getting consistent answers. That is one reason a lot of people don't yet believe string theory - it doesn't yet predict anything that is different from what our current models predict (at least the most successful, the less successful do not even correctly predict things we know are reality). "clearly the universe doesn't obey any rules of finity" What does this mean? I am asking to find out, I am not belittling, but trying to understand. *Thag is well know for coming up with the theory, which he than proved (at the cost of his life) that getting pounded by a Stegosauria tail can hurt you (see thagomizer[^])
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It's not about proving or disproving it with philosophy, just that with a non (or less) scientific perspective where an object does not need to exist in an instance to perform a measurement (in that instance) would yield entirely different results than if there was an object there to interfere with its surroundings. This then becomes a discussion for philosophers. Sure, philosophy is not entirely out of place in the realm of science (being that science evolved from philisophical theory), but a scientist is bound by previous measurements (a measurement being a result that has lead to the development of a tool/platform/framework) I just think that philosophy can go much further in explaining the how or how not of the existence of determinism, and to put scientific restriction on a proof is just a very scientific thing to do because humankind has done so in the past, when scientific theory may not be the best way to approach it. My reference to the universe not obeying any rules of infinity simple alludes to the fact that infinity is also a man-made concept. It exists to explain something that we can not understand. Sure, in mathematics, we can 'understand' that numbers can be counted forever, but our comprehension of what exists beyond the edge of the universe is non-existent (that assumes there is an edge to the universe, because a edge generally implies finity :P)
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I posted:
however you cannot control which dimensions you are sampling from...
as per you response
Andy Brummer wrote:
Most of what you posted doesn't even apply to the issue I'm bringing up. As I understand it, garden variety quantum mechanics measurement works like this. Given a wave function phi, the probability of observing it it in state theta is |< phi | theta >|2 end of story. It's got nothing to do with perturbing the object being measured, random number generators or any of that, it is just what taking a quantum measurement means. All the other stuff is about specific cases of the wave function. It's got nothing to do with the basic axioms of QM.
this is not a question of garden variety quantum mechanics. all measurements perturb. (see Feynmann above(he got a Nobel pertaining to the issue)) the "Axioms" (from wikipedia) Main article: Theory of incomplete measurements[^] The theory of incomplete measurements (TIM) derives the main axioms of quantum mechanics from properties of the physical processes that are acceptable measurements. In that interpretation: * wavefunctions collapse because we require measurements to give consistent and repeatable results. * wavefunctions are complex-valued because they represent a field of "found/not-found" probabilities. * eigenvalue equations are associated with symbolic values of measurements, which we often choose to be real numbers. The TIM is more than a simple interpretation of quantum mechanics, since in that theory, both general relativity and the traditional formalism of quantum mechanics are seen as approximations. However, it does give an interesting interpretation to quantum mechanics. -end wikipedia-- everything I said does in fact pertain because the original post was about a finite state machine(QIT) and the "axioms" above don't pertain to quantum information.. which
**is different then just simply measuring a wavefunction**. your "Hamiltonian" is not using the information about the finite state machine nor the entropy of the system (they don't teach this in undergrad courses) as a result you are using the wrong wavefunctionFrom ArXiv [Operational Axioms for Quantum Mechanics^] Reference section 8 observables, remark 7, definition 15, subsequent paragraph (pg. 16); The present notion of predictability for effects corresponds to that of "decision effects" of Ludwig [4]. For a predictable transformation A one has ||A || = 1. Notice that a predictable transformation is not deterministic, and it can generally occur with nonunit probability on some state w.
**Predictable effects A correspond to affine functions fA on the state space S with 0 <= fA <= 1 achieving both bounds**so sometimes yes random, other times, no deterministic. It depends on what the problem is and how you are looking at. -
It's not about proving or disproving it with philosophy, just that with a non (or less) scientific perspective where an object does not need to exist in an instance to perform a measurement (in that instance) would yield entirely different results than if there was an object there to interfere with its surroundings. This then becomes a discussion for philosophers. Sure, philosophy is not entirely out of place in the realm of science (being that science evolved from philisophical theory), but a scientist is bound by previous measurements (a measurement being a result that has lead to the development of a tool/platform/framework) I just think that philosophy can go much further in explaining the how or how not of the existence of determinism, and to put scientific restriction on a proof is just a very scientific thing to do because humankind has done so in the past, when scientific theory may not be the best way to approach it. My reference to the universe not obeying any rules of infinity simple alludes to the fact that infinity is also a man-made concept. It exists to explain something that we can not understand. Sure, in mathematics, we can 'understand' that numbers can be counted forever, but our comprehension of what exists beyond the edge of the universe is non-existent (that assumes there is an edge to the universe, because a edge generally implies finity :P)
c0ward wrote:
... where an object does not need to exist in an instance to perform a measurement ... would yield entirely different results than if there was an object there to interfere with its surroundings.
I have to admit, not having the object there is going to give you different results, since it won't interfere with the measurement. I agree that 'philosophy' can get us going in directions that we might not, but without requiring an agreement with reality, I don't think that gets you anything. Philosophy gave us the idea that the nipples were connected to the uterus. The idea that an object that is going in a spiral will continue to do so one released. On the other hand, gerdunkin is what got us relativity. The difference is that the first two were divorced from a requirement to model reality. Infinity is not a man-made idea, any more than 'thought' is a man made idea. Infinity falls out of the math. It does not get put into the math, it falls out of it with no more human intervention than writing the equation. The same way Maxwell's equations have basic values of the electron fall out of them, not because people put it in, but because the math yields it. We describe a bird, but that does not make it an artifice.
Silver member by constant and unflinching longevity.
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I posted:
however you cannot control which dimensions you are sampling from...
as per you response
Andy Brummer wrote:
Most of what you posted doesn't even apply to the issue I'm bringing up. As I understand it, garden variety quantum mechanics measurement works like this. Given a wave function phi, the probability of observing it it in state theta is |< phi | theta >|2 end of story. It's got nothing to do with perturbing the object being measured, random number generators or any of that, it is just what taking a quantum measurement means. All the other stuff is about specific cases of the wave function. It's got nothing to do with the basic axioms of QM.
this is not a question of garden variety quantum mechanics. all measurements perturb. (see Feynmann above(he got a Nobel pertaining to the issue)) the "Axioms" (from wikipedia) Main article: Theory of incomplete measurements[^] The theory of incomplete measurements (TIM) derives the main axioms of quantum mechanics from properties of the physical processes that are acceptable measurements. In that interpretation: * wavefunctions collapse because we require measurements to give consistent and repeatable results. * wavefunctions are complex-valued because they represent a field of "found/not-found" probabilities. * eigenvalue equations are associated with symbolic values of measurements, which we often choose to be real numbers. The TIM is more than a simple interpretation of quantum mechanics, since in that theory, both general relativity and the traditional formalism of quantum mechanics are seen as approximations. However, it does give an interesting interpretation to quantum mechanics. -end wikipedia-- everything I said does in fact pertain because the original post was about a finite state machine(QIT) and the "axioms" above don't pertain to quantum information.. which
**is different then just simply measuring a wavefunction**. your "Hamiltonian" is not using the information about the finite state machine nor the entropy of the system (they don't teach this in undergrad courses) as a result you are using the wrong wavefunctionAwesome. I'll definitely read up on TIM. Are there any other good resources beyond the wiki article and links from there?
ely_bob wrote:
all measurements perturb.
Yeah, some sloppy statements on my part there. I was trying to distance my statement from an incorrect analogy to the uncertainty principle. You don't have to do a measurement on a system to see the effects, the measurement just has to be possible in principle. Most simple measurements will perturb like bouncing an electron off and atom will move the atom, but the quantum uncertainty in measurement is a more subtle effect above and beyond the simple statistical randomness we are used to thinking about.
ely_bob wrote:
sorry if my tone is a little harsh... this is razzing me.
I did call your post out as bs, as I thought it threw a bunch of random terms and thoughts together without giving a coherent explanation. Not that it is easy with QM. Human languages are horrible at describing what goes on at a quantum level, and almost every analogy to QM behavior that I've seen, has had some major flaws that end up confusing more than enlightening. It seems that equations and computations are the only real tool out there. With newton you can talk about rocks and gravity, no problem. With classical EM you can reason with field lines and the like, there are some really simple physical concepts hidden in there. Even relativity just changes the basic angles of action measure from parabolic to hyperbolic, QM is nothing like classical mechanics. Even without measurement, it doesn't even operate on the same phase space as classical mechanics. I'm not looking for a GUT or anything like that but it would be fantastic if there was one formulation for simple mechanics that had 2 parameters, c and h. Set both to 0 and you get Newtonian mechanics, just c non-zero = special relativity, just h non-zero you get the Schrodinger equation, c and h would give you relativistic QM. But from what I understand they are all different. Anyway, best of luck to you on your studies. There is definitely a part of me that is totally jealous of you.
I can imagine the sinking feeling one would have after ordering my book, only to find a laughably ridiculous theory with demented logic once the book arrives - Mark McCutcheon
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Does not the physics of QM provide for "true randomness" in the Universe? I'm debating a friend who seems to think everything is predetermined, period. My argument against, is that his proposal would be a finite machine, one which could be moved either forward or back. Additionally, my argument continues, if true randomness exists, then it can't be predetermined nor undone. Am I incorrect? Any thoughts?
There are various types of interpretation of quantum mechanics. The idea which seems to affect your thought or at least the question asked, is related to what is called stochastic quantization, which is a part of semi-classical approach. In actual practice, if you wish to interpret the results and thoughts of quantum mechanics you will have to understand that whatever interpretation you take, it should be consistent and should not have many "even-driven" constraints. At least this is what we call the natural way of thinking. Therefore instead of saying this is wrong and that is correct, I would suggest you to think in terms of speakable and non-speakable. That is, we write down certain assumptions and decide that the statements which violates these assumptions are not allowed to be made, in other words, these are unspeakable. This is no way of leaving query unanswered. In fact if there is a problem, first formulate it and ask speakable questions and it may turn out to be a solvable problem. This approach has helped the theoretical and experimental physicist in understanding most of the problems of quantum-scale physics. I will not provide a full fledged lecture on this issue, because this is not a forum of discussing physics, rather I will note down following two assumptions, a small discussion, with a note: and the note is: whatever appears in mathematics may not be directly interpretable. Only "observables" have the interpretations. Assumption (1) is related to the observation: In order to observe something you need to define a mathematical state, traditionally known as vacuum, which is a "linear combination of all possible states". All possible states defines what is called the vector space. The size of vector space can be countable-finite, uncountable-finite or simply infinite. But they cannot be continuous. For example the set of angular quantum number of an atom is finite and it is quantum-mechanical property, while the possible state of a Hydrogen atom is discrete but infinte. Assumption (2) deals with the the mechanism of observation: it defines a mathematical procedure which when applied on the mathematical state of the system, something happens to the internal arrangement of the state. The state may or may not change. The mathematical procedure is known as operators. We cannot derive an interpretation for the operators. Interpretation, as we have noted earlier, is related to observables only. Now we can define what is an observable: Mathematicaly speaking, an operator having real non-zero eige
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If someone is looking at it, they did so by bouncing a photon off it. That made it move. This isn't like listening for the sound of a tree falling. It's more like seeing if a tree has already fallen or not by hitting it with a chainsaw.
Jane Williams wrote:
If someone is looking at it, they did so by bouncing a photon off it.
Hey, I thought the concept that our eyes somehow interact with the world, rather than receiving emitted lights got disproved around the time of Ancient Egypt, but, like creationism, I guess there's always someone willing to believe the old models.
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Jane Williams wrote:
If someone is looking at it, they did so by bouncing a photon off it.
Hey, I thought the concept that our eyes somehow interact with the world, rather than receiving emitted lights got disproved around the time of Ancient Egypt, but, like creationism, I guess there's always someone willing to believe the old models.
Well, if you need it spelled out... Photon (from unknown and irrelevant source) hits particle. Moves particle. Photon leaves particle, travels to eye. Eye says "ooh, look, particle is over there". It's wrong.
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Randomness must be defined with respect to predictability. If you have a good random-number generator, you won't be able to predict the numbers, and it will be random. BUT, if you get the algorithm used by the random-number generator, you WILL be able to predict them, and THEY WILL NO LONGER BE RANDOM. If you knew the state of every particle in the universe, you could predict everything. In a sense everything is predetermined. But since in reality we don't have that predictability, everything's random for all practical purposes.
Sorry but very wrong! Heisenberg... (You can't know the states of all particles...)
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My verbage isn't that great, but I think I get my point accross ok... Every action has an equal and opposite reaction. This can be taken as true in any form from an atomic level to a macro level (solar systems and galaxies). As far as I know, you can safely say that each molecule affects the molecule next to it, to some degree, and in the same regard each atom reacts from interaction with other atoms around it. Like a game of marbles, each flick of a marble has an impact on all the other marbles near it; you project the marble with force, and based on so many variables such as gravity, speed, acceleration, mass, velocity, surface area, etc, etc, it hits another marble sending it moving along it's OWN course. Obviously losing energy through other resistances such as friction the second marble may hit a third marble, repeating these effects, but to a lower degree, until all that energy is disipated and the marbles no longer move. You could say that throwing that marble a billion times will NEVER render the exact same results; there will always be some kind of "randomness" associated with the event, and this is completely true. Throw it forever, and you will no doubt never see the same outcome. However, this does not mean that true randomness exists in our universe. Say we were using the big bang as a point of origin for an event. Similar to the marbles, the explosion sends debris, rocks, elements, gasses, energy, etc eminating, rather speeding away from the event horizon heading out into the universe (or as some presume, CREATING the universe itself by expanding at the speed of light). Now at a macro level these bits and pieces hitting each other cause enormous explosions and other major disruptions in space-time, which in turn ricochet off on their own courses, causing more explosions, et al. Imagine, however, what is happening at an atomic level. Atoms changing, breaking apart(?), forming molecules, etc, but importantly, the path of each individual atom is governed entirely by the forces and resistances surrounding it, and of course in large part by other atoms hitting it (or coming close and deterring them electromagnetically(?)). If you knew the position of every single atom in existence at any one point in time :wtf: , you could without error predict the movement of the entire universe, or the exact, and i mean EXACT path of a marble that has been hit by another marble, that was itself hit by a marble being flicked.... You could predict EXACTLY the movement of the leaves on a tree, an
No! What you are talking about is CLASSIC Mechanic - there everything is dertermined in the way you explained, but thats not true for QM!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! So your tree experiment is not possible (even theoretical!) (I studied Physics...)
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There are various types of interpretation of quantum mechanics. The idea which seems to affect your thought or at least the question asked, is related to what is called stochastic quantization, which is a part of semi-classical approach. In actual practice, if you wish to interpret the results and thoughts of quantum mechanics you will have to understand that whatever interpretation you take, it should be consistent and should not have many "even-driven" constraints. At least this is what we call the natural way of thinking. Therefore instead of saying this is wrong and that is correct, I would suggest you to think in terms of speakable and non-speakable. That is, we write down certain assumptions and decide that the statements which violates these assumptions are not allowed to be made, in other words, these are unspeakable. This is no way of leaving query unanswered. In fact if there is a problem, first formulate it and ask speakable questions and it may turn out to be a solvable problem. This approach has helped the theoretical and experimental physicist in understanding most of the problems of quantum-scale physics. I will not provide a full fledged lecture on this issue, because this is not a forum of discussing physics, rather I will note down following two assumptions, a small discussion, with a note: and the note is: whatever appears in mathematics may not be directly interpretable. Only "observables" have the interpretations. Assumption (1) is related to the observation: In order to observe something you need to define a mathematical state, traditionally known as vacuum, which is a "linear combination of all possible states". All possible states defines what is called the vector space. The size of vector space can be countable-finite, uncountable-finite or simply infinite. But they cannot be continuous. For example the set of angular quantum number of an atom is finite and it is quantum-mechanical property, while the possible state of a Hydrogen atom is discrete but infinte. Assumption (2) deals with the the mechanism of observation: it defines a mathematical procedure which when applied on the mathematical state of the system, something happens to the internal arrangement of the state. The state may or may not change. The mathematical procedure is known as operators. We cannot derive an interpretation for the operators. Interpretation, as we have noted earlier, is related to observables only. Now we can define what is an observable: Mathematicaly speaking, an operator having real non-zero eige
Amen! :rose: