Quantum Mechanics
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Chris Maunder wrote:
Below a certain threshold the universe is fuzzy. The more you try and measure the position of a particle, the less you will be able to measure its momentum, and vice versa.
Ok, this is what I also believe, but isn't that only if WE attempt to measure or intercept a particle? The laws of physics that govern a particle or something so small are different to the laws for objects the size of, say, a human being, or Earth. So trying to measure or observe the characteristics of a particle in our real-time 'macro-verse'(?) could potentially report incorrect results, or missing or contradictory information. Are the properties of the 'fuzzy' parts of the universe not completely defined simply because we cannot measure them effectively? Don't a particles properties exist as a uniform constant regardless of the outcome that the observers best attempts had at defining them? Does a falling tree make a sound if there's no one there to hear it? :-\ Am I completely off track? I have to review every bloody sentence I write! :doh:
MichaelGallagher wrote:
nly if WE attempt to measure
I knew CPians were important - but surely not omnipotent :)
MichaelGallagher wrote:
The laws of physics that govern a particle or something so small are different to the laws for objects the size of, say, a human being, or Earth.
They;'re not different - it's just that you can ignore very small things most of the time - like you don't take into account the increase in mass of a train accellerating away from the station - because the increase in mass is tiny compared to the mass of the train - but it still happens.
MichaelGallagher wrote:
Are the properties of the 'fuzzy' parts of the universe not completely defined simply because we cannot measure them effectively
No they are fuzzy because they are not determined until a measurement happens and no that measurement isn't 'by us' but by anything -
MichaelGallagher wrote:
Does a falling tree make a sound if there's no one there to hear it?
Of course. But does a photon go through the left or right slit if nobody is watching? The answer, my friend, is blowing in the wind.
MichaelGallagher wrote:
Am I completely off track? I have to review every bloody sentence I write!
The issue is, I find, that the mathematically challenged (and by this I mean those without a Phd in the subject) have to necessarily have concepts 'dumbed down' and it is the language that confuses.
___________________________________________ .\\axxx (That's an 'M')
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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?
Hi, Quantum Mechanics is a such big topic in physics. And more important, it is the topic try to describe ALL physics system at microscopic scale. The word "predetermined" in physics, most likely means, if you have a input, then you can compute the output. The randomness in quantum physics is because of the daul features of small particles. I guess you mix the true physics with science fiction. Besides, physicists are also try to make the randomness less random. To them, the randomness is not random, it is just something they still cannot formulize yet. When you talk about predict the future and undo the past, it sound more like time travel. By right now, no one konws it can be done or not. It is only theoretic. There are something called Novikov self-consistency principle and parallel universes. You may want to read. I personally more prefer parallel universes. Regards.
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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?
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)
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MichaelGallagher wrote:
nly if WE attempt to measure
I knew CPians were important - but surely not omnipotent :)
MichaelGallagher wrote:
The laws of physics that govern a particle or something so small are different to the laws for objects the size of, say, a human being, or Earth.
They;'re not different - it's just that you can ignore very small things most of the time - like you don't take into account the increase in mass of a train accellerating away from the station - because the increase in mass is tiny compared to the mass of the train - but it still happens.
MichaelGallagher wrote:
Are the properties of the 'fuzzy' parts of the universe not completely defined simply because we cannot measure them effectively
No they are fuzzy because they are not determined until a measurement happens and no that measurement isn't 'by us' but by anything -
MichaelGallagher wrote:
Does a falling tree make a sound if there's no one there to hear it?
Of course. But does a photon go through the left or right slit if nobody is watching? The answer, my friend, is blowing in the wind.
MichaelGallagher wrote:
Am I completely off track? I have to review every bloody sentence I write!
The issue is, I find, that the mathematically challenged (and by this I mean those without a Phd in the subject) have to necessarily have concepts 'dumbed down' and it is the language that confuses.
___________________________________________ .\\axxx (That's an 'M')
Maxxx_ wrote:
The issue is, I find, that the mathematically challenged (and by this I mean those without a Phd in the subject) have to necessarily have concepts 'dumbed down' and it is the language that confuses.
Generally mathematics isn't my biggest problem. The problem is I question authority a lot, even if that authority is Einstein himself. Of course a question without an answer is just a statement. :-\ I remember reading about Einstein and how he disliked mathematics so much that he had his friends (Max Planck(?)) do the calculations for him so he could submit his formulae to the universities or other institutions. If it wasn't for my lack of understanding I wouldn't have learned a thing! Thanks to you guys i'm headed to the library this afternoon! Sure, the internet is there, but i'm sure at one point Wikipedia said Gravity didn't exist... :wtf:
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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?
What a great question, and one that carries with it some memories of a philosophy final exam written while exceedingly drunk resulting in an A+ grade. Unfortunately the instructor left on sabbatical the next day and I never got my test paper back, so I have no idea what I wrote. At my level of understanding, which I realize is only nominal, QM proposes a universe which is statistical in nature, rather than fully determinate. What your friend proposes is that, given a small piece of fairy cake, it should be possible to extrapolate the past and future of the entire Universe from the arrangement of the molecules in that cake at any given moment. If that is the case, then the Universe can be represented as a state machine. A state machine, however, can be reversed, and doing so implies in the real world, a reversal of entropy. I haven't observed that happening anytime recently, so I'm inclined to reject that view of the Universe. I have trouble with your view, as well; reality, in my experience, has branching points at which decisions are made by conscious beings which alter the path which reality travels. Some are irreversible, some are not. That's what makes life interesting. I strongly believe that we, as conscious beings, influence the course which reality travels by the choices we make, but those choices are not random. At least, they're not entirely random... Somewhere in the middle lies the real answer, but where it lies I don't know. That the laws of physics control most reactions I cannot deny; in that respect a state machine model may be appropriate. But I've seen too many things that defy that model to believe in it entirely.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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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?
I'm with your friend here, everything is predetermined. "Random" and "probability" is just mathematical methods used when you are unable to calculate the outcome due to lack of understanding or lack of data.
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MichaelGallagher wrote:
does that mean an exact state doesn't exist?
My understanding is that yes, that's exactly what it means - in the 'slit' experiment with a single photon going through the slit, its state does not exist until it is measured.
___________________________________________ .\\axxx (That's an 'M')
Maxxx_ wrote:
My understanding is that yes, that's exactly what it means - in the 'slit' experiment with a single photon going through the slit, its state does not exist until it is measured.
It's state must surely exist all the time. How else can it interact with everything else in a meaningful manner? Regardless of whether anyone is looking or not... This thing about canging models (wave or particle) and behavior depending on who (if any) is looking is just pure nonsence to me.
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Maxxx_ wrote:
My understanding is that yes, that's exactly what it means - in the 'slit' experiment with a single photon going through the slit, its state does not exist until it is measured.
It's state must surely exist all the time. How else can it interact with everything else in a meaningful manner? Regardless of whether anyone is looking or not... This thing about canging models (wave or particle) and behavior depending on who (if any) is looking is just pure nonsence to me.
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.
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Kastellanos Nikos wrote:
claiming entanglement
Nah, that's only if he kicks back simultaneously!
¡El diablo está en mis pantalones! ¡Mire, mire! SELECT * FROM User WHERE Clue > 0 0 rows returned Save an Orange - Use the VCF! VCF Blog Just Say No to Web 2 Point Oh
And only if one of you is looking at the time :)
The only thing unpredictable about me is just how predictable I'm going to be.
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MichaelGallagher wrote:
my atoms are being affected by other atoms
affected != determined :)
Luc Pattyn [Forum Guidelines] [My Articles]
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(psst VB guys .. thats .. affected <> determined) ;)
The only thing unpredictable about me is just how predictable I'm going to be.
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achimera wrote:
Does not the physics of QM provide for "true randomness" in the Universe?
If you will pardon the pun it is uncertain if that is the case. We do not know how to get from our description (which are a probability distribution of where a particle might be) to where it is - our tools do not allow it. We don't think there are 'hidden state variables' that contain more information than we are able to discern, so we currently believe that the outcome of any quantum reaction is truly random. Even if it is not truly random, we don't know what will happen, and it sure looks that way to us. It could be predetermined at some level that we don't know about, but we have no data available to us about that level. In the end, we are only able to state with certainty that we can not characterize it at anything other than a probabilistic manner. So, it is a nice argument to have, and you can say that, at our current level of knowledge, which we believe to give an almost complete understanding of 'normal' conditions (and a pretty good one of relativistic conditions) we are only able to give a statistical description of what will happen. So to us, it looks random, and we do not know more than that, or even if there is more than that to know. Maybe it is predetermined, maybe it is not, you can only know what you can know. I think it was best described as "you can't get there from here". If, on the other hand, your friend believes that God made everything, and that He predetermined everything, ask him if the Bible does not also talk about free will. God may fully know everything that will happen, while at the same time having let us do whatever we want. While we see time go by, and make our free will decisions, God seems to have a complete view of 4-D space-time at once, based on Bible reading, so, in his view, it has all 'happened'. Thinking about the motion of 4+ dimensional 'branes may be fully capable of frying brains.
Silver member by constant and unflinching longevity.
4D? Only 4? I think you'll find you need a few more dimensions than that :(
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MichaelGallagher wrote:
If you knew the position of every single atom in existence at any one point in time , 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....
I believe Socrates already debated that particular argument thousands of years ago. As I understand it, QM provides the exact state of an atom cannot be determined, it can only be estimated or predicted. If so, then there is never any certainty -- thus the uncertain portion would lead to "randomness", would it not?
Actually I have to say that's one aspect that I've never quite grasped (among the many in QM that make my brain bleed). I've always wondered whether the fact that exact state can not be determined is a true indication of whether that state actually exists. If the state exists but some property of the system makes it impossible for us to determine or whether state just isn't known (even to itsself). Excellent, I started off this post understanding what I thought I understood .. until I examined it .. (spooky).
The only thing unpredictable about me is just how predictable I'm going to be.
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And only if one of you is looking at the time :)
The only thing unpredictable about me is just how predictable I'm going to be.
Nah! If you're looking it can't do 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.”
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MichaelGallagher wrote:
If you knew the position of every single atom in existence at any one point in time , 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....
I believe Socrates already debated that particular argument thousands of years ago. As I understand it, QM provides the exact state of an atom cannot be determined, it can only be estimated or predicted. If so, then there is never any certainty -- thus the uncertain portion would lead to "randomness", would it not?
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.”
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Kick him in the shin, they say "Hey! I'm sorry, you were right all along, it's all predetermined, I couldn't prevent it". Then see what he says ...
The universe is random fundamentally, but emergently ordered macroscopically because it is bounded by probability. What I mean by that is that at the quantum level there's nothing to stop a particle from ceasing to be here and spontaneously appear over there, it's just very unlikely. In fact quarks and anti-quarks spontaneously appear and anhillate each other all the time. We like to think of an electron as a point. A solid particle. It's not. It's a fuzzy potential field around an atom. Everything in this universe is probability nothing more.
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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?
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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)
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I'm with your friend here, everything is predetermined. "Random" and "probability" is just mathematical methods used when you are unable to calculate the outcome due to lack of understanding or lack of data.
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Yeah that sounds quite logical, but just because an exact state can't be determined, does that mean an exact state doesn't exist? I'll have to read up on Socrates, sounds really interesting. The thing I love about science is that a lot of fundamentals were uncovered by guys in the last couple thousand years, without all the technical abilities and tools we have today, because the principles are all around us, in nature, in many forms, and to have a fundamental understanding of them you don't really need to understand the mathematics, just picture the process in your head. In fact, they may have had an advantage over others today; not having been already brainwashed with certain "facts" about our universe and not having the preassure of religion telling them they are unequivocally wrong (well, not all the time). So simple, yet so complex! Einstein, what a legend.
Actually yes, it does mean that an exact state does not exist. Until an 'observation' causes the probability wave to collapse into something real. The really weird side effect is that some things can only happen when they're not being observed. Don't peek or the universe stops working. The one that depressed me is that above a certain number particles become self observant. So for instance you couldn't really put Schrodinger's cat into a state of flux. Too many atoms. I do still have hopes for creating an entangled cat though. :cool:
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MichaelGallagher wrote:
If you knew the position of every single atom in existence at any one point in time , 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....
I believe Socrates already debated that particular argument thousands of years ago. As I understand it, QM provides the exact state of an atom cannot be determined, it can only be estimated or predicted. If so, then there is never any certainty -- thus the uncertain portion would lead to "randomness", would it not?
thus the uncertain portion would lead to "randomness", would it not? <<<br mode="hold" /> Within limits. The limit is the boundary between the micro and macro perspective. At some point, as we increase in scale from the subatomic level, stoichastic processes become bounded by their peers, in effect becoming statistical rather than real. As has been stated previously, the illusion of determinism isn't really an illusion above a certain scale. Randomness just fades into the background noise. The source of confusion is uncertainty as to where that boundary exists, as well as human inability to perceive it. Without specialized apparatus, we're unable to become privy to the randomness underlying it all, and so all we perceive is the Newtonian reality.