morgsboi Posted January 22, 2012 Posted January 22, 2012 Well, I don't know what to tell you guys. The electron you measure isn't a wave, it's a point, and since we are not getting infinitely continuous measurements of the point, we can not observe that the point is moving any distance over time or that it has any momentum or kinetic energy, so I guess if time stops, what is it relative to? The multi-verse theory? The multi-verse theory? And then of course multi-multi-verse and so on. It's impossible to cool an object to 0K. Would the radiation bouncing off it count?
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) The multi-verse theory? How do you get multi-verse theory from the specific annihilation of a probability wave? It's impossible to cool an object to 0K. We aren't "cooling it", it's just suddenly existing as a sudden measurement of something which has no K since it is not moving it all and has no energy to generate wave mechanics during the time it is measured. Edited January 22, 2012 by questionposter
D H Posted January 22, 2012 Posted January 22, 2012 (edited) Achieving absolute zero is impossible per the third law of thermodynamics, one statement of which is It is impossible by any procedure, no matter how idealized, to reduce any system to the absolute zero of temperature (0 K) in a finite number of operations. This is not proven fact (no scientific theory is), so let's look at the hypothesis that time stops at T=0. This is exactly backwards. Time moves fastest at T=0. Imagine a diamond of pure carbon 14. (Diamonds are forever? Not if they're made of C-14.) An observer at rest with respect to the diamond will observe the diamond decay into nitrogen 14 with a half-life of 5,730 years. A relativistic observer will observe a longer half-life. If the diamond has a non-zero temperature, the atoms in the diamond will be vibrating back and forth. An observer at rest with respect to the diamond as a whole is a relativistic observer. The mean velocity is so low that these relativistic effects are not observed, but they nonetheless do exist. These relativistic effects become smaller and smaller as T→0. The decay rate increases (by an imperceptible amount) as temperature decreases. Time moves fastest at T=0. Edited January 22, 2012 by D H
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) Achieving absolute zero is impossible per the third law of thermodynamics, one statement of which is It is impossible by any procedure, no matter how idealized, to reduce any system to the absolute zero of temperature (0 K) in a finite number of operations. This is not proven fact (no scientific theory is), so let's look at the hypothesis that time stops at T=0. This is exactly backwards. Time moves fastest at T=0. Imagine a diamond of pure carbon 14. (Diamonds are forever? Not if they're made of C-14.) An observer at rest with respect to the diamond will observe the diamond decay into nitrogen 14 with a half-life of 5,730 years. A relativistic observer will observe a longer half-life. If the diamond has a non-zero temperature, the atoms in the diamond will be vibrating back and forth. An observer at rest with respect to the diamond as a whole is a relativistic observer. The mean velocity is so low that these relativistic effects are not observed, but they nonetheless do exist. These relativistic effects become smaller and smaller as T→0. The decay rate increases (by an imperceptible amount) as temperature decreases. Time moves fastest at T=0. People said nothing could have infinite thermal conductivity and liquid helium proved that wrong. People said noble gases couldn't form compounds and xenon di-fluoride proved that wrong. People said nothing could be a super conductor but more than one substance proved that wrong. Anyway, if an electron is defined as at point, then it's not a wave, and no wave means no energy to oscillate, so what we measure is a point containing 0 energy which is why its a point and not a wave. Because if we have energy, well then there's a bunch of equations describing wave mechanics, but a point isn't a wave so a point doesn't follow wave mechanics. And since from any known point of reference the point cannot be measured traveling distance over time unless a point of reference could get infinitely continuous data measurement, it has to have 0 kinetic energy upon measurement. It's not that it's universal, it's that every point of reference is individually measuring a wave-particle the same way as to cause it to become a point upon that measurement, which suggests that there is perhaps a point of reference that can measure it as to not cause it's time to stop or have 0K. Also, doesn't something have to be moving in some way from any point of reference? I mean it doesn't have to move the same way, but I mean the speed of light is universal even though you can measure different frequencies of light, why can't other things be universal? Edited January 22, 2012 by questionposter
DrRocket Posted January 22, 2012 Posted January 22, 2012 Theoretically, if an object has 0 kinetic energy, then it would mean that it's time stops, incorrect In fact in special relativity a clock at rest with respect to a given observer, the clock which measures time in that observer's rest frame, has zero kinetic energy.
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) incorrect In fact in special relativity a clock at rest with respect to a given observer, the clock which measures time in that observer's rest frame, has zero kinetic energy. I understand that a clock could "appear" at rest, but truthfully it logically can't be at rest because there are practically infinite factors moving it and effecting it. In fact, any clock on Earth that seems at rest is just moving at too slow of a speed or has vibrations occurring too fast or too slow to measure with your eyes that it's not at rest and is actually moving around the galaxy while the Earth is rotating. Again, exact speed isn't universal, but the fact that something is moving is. Just like the speed of light is universal but the frequency you measure it at isn't, or maybe the fact that time flows everywhere but it doesn't flow at the same rate everywhere. Edited January 22, 2012 by questionposter
DrRocket Posted January 22, 2012 Posted January 22, 2012 I understand that a clock could "appear" at rest, but truthfully it logically can't be at rest because there are practically infinite factors moving it and effecting it. In fact, any clock on Earth that seems at rest is just moving at too slow of a speed or has vibrations occurring too fast or too slow to measure with your eyes that it's not at rest and is actually moving around the galaxy while the Earth is rotating. Again, exact speed isn't universal, but the fact that something is moving is. Just like the speed of light is universal but the frequency you measure it at isn't, or maybe the fact that time flows everywhere but it doesn't flow at the same rate everywhere. Certainly a clock can be at rest. Just pick the rest frame of the clock. There is no such thing as absolute motion. The fact that something moving is most emphatically NOT universal.
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) Certainly a clock can be at rest. Just pick the rest frame of the clock. There is no such thing as absolute motion. The fact that something moving is most emphatically NOT universal. So if nothing is universal, then from some point of reference I should be able to measure light not traveling at the speed of light, or that something is traveling faster than light, or that gravity get's weaker by the cube of the distance rather than the square of the distance, or that energy=mass times the speed of light quintupled... If I pick up a clock, the vibrations generated by my heartbeat move it, even if it's not noticeable. So do the vibrations from motion within the Earth's crust as well as random neutrino and cosmic-ray hits and all the particles HAVE to be moving because they don't have 0K when your not measuring them, which means the particles of the clock are in some way "moving back and forth" due to kinetic energy and definitely due to unnoticeable vibrations that are proven to exist. Edited January 22, 2012 by questionposter
D H Posted January 22, 2012 Posted January 22, 2012 (edited) So if nothing is universal, then from some point of reference I should be able to measure light not traveling at the speed of light, or that something is traveling faster than light, The speed of light is the same to all observers. What this means is that velocities don't add the way you think the do. Suppose you see two spaceships moving straight away from you in opposite directions, each going at 3/4 the speed of light. The people in either of those spaceships will see you as moving away from their spaceship at 3/4 the speed of light. They will not see the other spaceship as moving at 3/2 the speed of light. They will instead see it as moving at 24/25 the speed of light. or that gravity get's weaker by the cube of the distance rather than the square of the distance, or that energy=mass times the speed of light quintupled... You are leaping to conclusions based on a false premise. In fact, [math]E=mc^2[/math] (better said: [math]E^2 = (pc)^2 + (m_0c^2)^2[/math]) is a direct result of relativity. Before leaping to more conclusions, you should study physics a bit more. Edited January 22, 2012 by D H
swansont Posted January 22, 2012 Posted January 22, 2012 I don't even remember what theory, I think it just might have been something I heard from a high school teacher for an either physics or chemistry class, but I guess there isn't much that actually happens at absolute 0. But basically, the logic is that since everything is always moving in some way, if something didn't move at all in any way, it would have to mean time has stopped. Center-of-mass motion stops at 0K, but atoms would not collapse — the electron structure is intact. The measurement going on in an atomic clock is of the electronic structure. Motion of the atoms decreases the precision of clocks, so there has been a push to reduce it by cooling the atoms or ions being used. That results in better measurements, not the stoppage of time. There's an easy way to sidestep the issue of 0K and that is to consider a clock using a single ion. That ion is at rest in its own frame, and as a single particle it has no temperature one need worry about. The clock still works. Time does not stop.
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) <br class="Apple-interchange-newline"> The speed of light is the same to all observers. Then from any point of reference, one will observe a photon traveling at C, and this is because it is the inherent physics of the universe for it to act so, and it is also the inherent physics of the universe for us to measure particles the way we do. You are leaping to conclusions based on a false premise. In fact, [math]E=mc^2[/math] (better said: [math]E^2 = (pc)^2 + (m_0c^2)^2[/math]) is a direct result of relativity. Before leaping to more conclusions, you should study physics a bit more. No, it's pretty straight-forward. If nothing is universal, then not even physics itself should be constant. But as you said earlier, physics is, so there are some things that are universal. Center-of-mass motion stops at 0K, but atoms would not collapse — the electron structure is intact. The measurement going on in an atomic clock is of the electronic structure. Motion of the atoms decreases the precision of clocks, so there has been a push to reduce it by cooling the atoms or ions being used. That results in better measurements, not the stoppage of time. There's an easy way to sidestep the issue of 0K and that is to consider a clock using a single ion. That ion is at rest in its own frame, and as a single particle it has no temperature one need worry about. The clock still works. Time does not stop. Ok, now there's a conflict, because in the same page I have "0K is impossible" and "0k is completely possible". The objects making up something in a center-of-mass system are made out of atoms, and atoms are constantly moving in some way because they have energy, so if they have no energy, there would be no wave...oh wait, a point, it's not a wave, and we can't infinitely continuously measure that the point moves distance over time, so how is the point not having 0 kinetic or really 0 of any energy? When I say time stops, I don't mean the time of the universe stops, I mean just the time of one point of reference, either us from the point of reference of the particle, or the particle from the point of reference of us, stops. This notion of time stopping is really simple. Everything is always moving in some way from a point of reference, so if something wasn't moving from a point of reference, then it has to mean that from our point of reference that we're measuring it from that time has stopped for it. But, with a particle, since a measurement from our point of reference doesn't last forever, things will continue to go along. Edited January 22, 2012 by questionposter
immijimmi Posted January 22, 2012 Posted January 22, 2012 (edited) I was gonna put a post here about how it's impossible to measure a 0 in motion because it would mean inertia compared to everything else, and that we should be focusing on a zero in temperature. However something just ocurred to me: physicists used to think that motion was relative to the universe itself, right? Well, we know that light is always moving at c. To maintain this constant speed it cant really be moving relatively to anything, can it? We also think that it appears to move slower at times to to gravity, etc. curving spacetime around it. We've applied this to how black holes absorb light. If it appears to slow down when crossing an area containing a different 'density' of spacetime, then it's moving relative to that. In light of this, why aren't we measuring motion relative to the fabric of spacetime? that would mean that you have to take into account movement compared to this substance (if it can be called a substance) as well as temperature, if you want to stop an object's time. Or you could just flood the area with gravitons. Edited January 22, 2012 by immijimmi
questionposter Posted January 22, 2012 Author Posted January 22, 2012 Actually I have a whole nother realm of a question: If a photon hits an electron and get's re-emitted and head's towards an observer, is the location of where the photon hit the electron "recorded" within the photon, or is the location that we measure the electron at uncertain within the photon that we measure? In other words, is it predetermined where we will measure an electron at within a photon?
MigL Posted January 22, 2012 Posted January 22, 2012 Re-read the whole discussion. It seems you are confused about what happens when a measurement is made on a Quantum Mechanical system. By your misunderstanding, the collapse of the wavefunction when an observation is made, implies that the wave nature of the system becomes an actual point particle. That is NOT the way it works. Wave function collapse is an 'interpretation' to allow for the multitudes of possibilities represented by the wavefunction and the single observed result. The wavefunction does not collapse to a particle, and time certainly does not stop.
immijimmi Posted January 22, 2012 Posted January 22, 2012 Actually I have a whole nother realm of a question: If a photon hits an electron and get's re-emitted and head's towards an observer, is the location of where the photon hit the electron "recorded" within the photon, or is the location that we measure the electron at uncertain within the photon that we measure? In other words, is it predetermined where we will measure an electron at within a photon? ...What? The reason we see things which photons have bounced off is that the photons that are not absorbed are of a specific frequency or frequencies, which gives us the colour of the object. Put all the photons that enter your eyes together and you get an image. The photons that reached us don't carry an image of the incident. They won't have changed at all. We can't measure anything from this lone photon you're talking about unless we know some other details of the incident. (for example, we could measure when it happened if we knew where, by calculating distance/speed).
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) Re-read the whole discussion. It seems you are confused about what happens when a measurement is made on a Quantum Mechanical system. By your misunderstanding, the collapse of the wavefunction when an observation is made, implies that the wave nature of the system becomes an actual point particle. That is NOT the way it works. Wave function collapse is an 'interpretation' to allow for the multitudes of possibilities represented by the wavefunction and the single observed result. The wavefunction does not collapse to a particle, and time certainly does not stop. Except I'm not talking about the wave of a particle, I'm talking about that-which-you-measure, which is a point or single exactly defined result. When you measure a particle, even though the particle itself is a wave, the thing your measuring or seeing is a point, your not actually seeing an entire undefined wave, your somehow only seeing something as a point. Why doesn't someone just see what happens when they plug in "energy=0" for a wave mechanics equation? I'm pretty sure no energy means no wave anyway. So if what we are measuring matches what is generating by what happens when you plug in "energy=0", that what we are measuring is what happens when you plug in "energy=0" Maybe time doesn't stop from a point of reference, but nothing actually has 0K, so what else happens at 0K and what else is happening that turns a measurement from a wave to a point? Also, even though something can have a point of reference from itself, is Swan actually suggesting that every object relative to itself has achieved absolute 0? Why are there so many people that say absolute 0 is impossible if its that simple? Edited January 22, 2012 by questionposter
D H Posted January 22, 2012 Posted January 22, 2012 Also, even though something can have a point of reference from itself, is Swan actually suggesting that every object relative to itself has achieved absolute 0? Why are there so many people that say absolute 0 is impossible if its that simple? Individual atoms do not have a temperature. Temperature is a macroscopic phenomenon, not a microscopic one. You are still mis-mixing and mismatching a number of different concepts. There is no such thing as absolute rest or absolute motion. Get those notions out of your mind.
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) Individual atoms do not have a temperature. Temperature is a macroscopic phenomenon, not a microscopic one. You are still mis-mixing and mismatching a number of different concepts. There is no such thing as absolute rest or absolute motion. Get those notions out of your mind. Ok, but kinetic energy is different than temperature. Temperature is the measure of the average kinetic energy. A single atom doesn't have an average kinetic energy, but it does have just plain kinetic energy. Also, I'm not saying that you can't measure different motions from different points of reference, but every atom has some kind of kinetic energy. Just how light always travels at C but you can measure different frequencies. A property of kinetic energy is just that it causes things to move in some way shape or form just as a property of gravity is that it gets weaker by f=y/x^2 or a property of electro-magnetism is that it has parity or a property of light is that it travels at C. Some things are just beyond relativity. And again, why are there so many people who say 0K is impossible if all you have to do is pick up a clock to prove something has 0K? Actually, because of the uncertainty principal, there HAS to be motion because there will always be uncertainty about a particle's momentum, so a particle can't actually have 0K without I guess either time having been stopping or it just not existing at least as a wave any more. Also a distinction that somehow people still aren't recognizing is between an actual particle and a measurement. A measurement is different than a particle, that's why they have different definitions in the dictionary. The measurement you make is a point which is not traveling distance over time, where the measurement of a point came from is a particle which does travel distance over time. A measurement doesn't travel distance over time and therefore cannot have kinetic energy or even momentum which is why we don't observe a measurement as a wave, since you need energy to generate a wave. Edited January 22, 2012 by questionposter
D H Posted January 22, 2012 Posted January 22, 2012 Ok, but kinetic energy is different than temperature. Not really. The temperature of an object (if it has one) is just a measure of the average kinetic energy of the individual atoms/molecules in that object. You said so yourself: Temperature is the measure of the average kinetic energy. So which is it: Is temperature something different than kinetic energy, or a measure of the average kinetic energy? You can't have it both ways. One of the key moves afoot in metrology is to make several of the currently measured physical constants into defined constants. Example: The speed of light is now a defined constant. The latest meeting of the CGPM proposed making the Boltzmann constant k a defined constant, along with several others. Making the Boltzmann constant a defined value would explicitly tie temperature to kinetic energy, by definition. You appear to still be hung up on the idea of absolute motion. Drop that notion. Galileo (not Einstein) showed that this concept has limited validity. Einstein showed that it has no validity. None, zero, zip, nada. You need to drop this Aristotelian notion before you can make any progress in understanding the physics of the last 400 years.
Widdekind Posted January 22, 2012 Posted January 22, 2012 (edited) I understand, that "wave-function collapse to a point" is, rigorously, an exaggeration, which has never, actually, been observed. For example, in double slit experiments, the incident photon / electron wave-function "collapses", into one of many phosphor grains, coating the detector screen. But, those phosphor grains are [math]\approx 1 \mu m[/math] in size, characteristically. Thus, the wave-function "collapses", from a macro- or meso-scopic scale, to a micro-scopic scale, but, by no means, to "a point". I also understand, that the Schrodinger Wave Equation, is an approximation, to the more rigorous, and relativistically accurate, equations (e.g. Dirac equation, Klein-Gordon equation). Thus, the SWE implicitly embodies simplifying assumptions, whose omission could cause confusion. In particular, in the full relativistic equations, a particle's rest-mass-energy (mc2) defines that particle's intrinsic phase frequency. That could be included in the SWE, as [math]E \rightarrow E + mc^2, \omega t \rightarrow \left( \omega + \frac{mc^2}{\hbar} \right) t[/math]. Thus, a particle with zero KE, or even a negative bonding energy, still has a positive frequency (unless the negative bonding energy exceeds its rest-mass energy, which only occurs, in relativistically deep gravity wells). I understand, that that phase frequency is physically real, as the phase of wave-functions can be measured, e.g. Aharonov-Bohm effect. Thus, the wave-function, of a particle at rest, is still "spinning its phase", even if "its just sitting there", e.g. in its own rest-frame. Edited January 22, 2012 by Widdekind 2
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) Not really. The temperature of an object (if it has one) is just a measure of the average kinetic energy of the individual atoms/molecules in that object. You said so yourself: So which is it: Is temperature something different than kinetic energy, or a measure of the average kinetic energy? You can't have it both ways. One of the key moves afoot in metrology is to make several of the currently measured physical constants into defined constants. Example: The speed of light is now a defined constant. The latest meeting of the CGPM proposed making the Boltzmann constant k a defined constant, along with several others. Making the Boltzmann constant a defined value would explicitly tie temperature to kinetic energy, by definition. Having an average of kinetic energies is way different than looking at the kinetic energy of an individual atom. I'm not saying a specific kinetic energy is constant, I'm saying the fact that there is kinetic energy is constant, which is just like "the force of gravity is not constant, but the fact that all mass-particles have gravity is constant". You could even say that the gravity of Pluto on planet Earth is 0 because you can't feel it even though by the laws of gravity the gravity of Pluto has to be effecting us in some way. I understand, that "wave-function collapse to a point" is, rigorously, an exaggeration, which has never, actually, been observed. For example, in double slit experiments, the incident photon / electron wave-function "collapses", into one of many phosphor grains, coating the detector screen. But, those phosphor grains are [math]\approx 1 \mu m[/math] in size, characteristically. Thus, the wave-function "collapses", from a macro- or meso-scopic scale, to a micro-scopic scale, but, by no means, to "a point". I also understand, that the Schrodinger Wave Equation, is an approximation, to the more rigorous, and relativistically accurate, equations (e.g. Dirac equation, Klein-Gordon equation). Thus, the SWE implicitly embodies simplifying assumptions, whose omission could cause confusion. In particular, in the full relativistic equations, a particle's rest-mass-energy (mc2) defines that particle's intrinsic phase frequency. That could be included in the SWE, as [math]E \rightarrow E + mc^2, \omega t \rightarrow \left( \omega + \frac{mc^2}{\hbar} \right) t[/math]. Thus, a particle with zero KE, or even a negative bonding energy, still has a positive frequency (unless the negative bonding energy exceeds its rest-mass energy, which only occurs, in relativistically deep gravity wells). I understand, that that phase frequency is physically real, as the phase of wave-functions can be measured, e.g. Aharonov-Bohm effect. Thus, the wave-function, of a particle at rest, is still "spinning its phase", even if "its just sitting there", e.g. in its own rest-frame. With general relativity, it can't be spinning according to it's own frame of reference, from it's frame of reference everything else would be moving around it. That's why people thought stars revolved around the Earth. I know that a particle does have to be oscillating and moving in order for it to even exist as it does, but that's one of the problems here. This is where QM and GR for some reason don't mix. Anyway, we can't directly measure things as a wave, which only leaves things as a defined point, unless there's some other shape I'm missing. When you refer to the dimensions of the phosphorus, you are referring to when a photon effects phosphorous atoms and phosphorous atoms themselves occupy 3 dimensional space, but not the measurement of a photon bouncing off of that phosphorous atom itself. A measurement doesn't occupy space, it doesn't move distance over time, it's technically not even a real thing, because by the time you would measure the location of an electron, the electron had already gone into a state in which it has no defined location, unless somehow the measurement and the photon and the electron are still entangled...maybe. I suppose time stopping isn't logical even if people weren't understanding that I wasn't saying the time of the universe is stopping, but there is a difference between an object and the measurement of that object. Edited January 22, 2012 by questionposter
MigL Posted January 22, 2012 Posted January 22, 2012 But we don't measure to a dimensionless point... There is a limit to accuracy we can acheive, and it is fairly 'smeared out'. Also as Widdekind has explaned, put an EM wave through a double slit. Do you measure a point ??? Wish I had more time, gotta run.
questionposter Posted January 22, 2012 Author Posted January 22, 2012 (edited) But we don't measure to a dimensionless point... There is a limit to accuracy we can acheive, and it is fairly 'smeared out'. Also as Widdekind has explaned, put an EM wave through a double slit. Do you measure a point ??? Wish I had more time, gotta run. If you put an EM wave through a double slit, you technically don't even measure the phosphorous, you measure a photon, which is why there should be a distinction between a measurement and the object you measure. A point I think also occupies one dimension. Edited January 22, 2012 by questionposter
DrRocket Posted January 23, 2012 Posted January 23, 2012 So if nothing is universal, then from some point of reference I should be able to measure light not traveling at the speed of light, or that something is traveling faster than light, or that gravity get's weaker by the cube of the distance rather than the square of the distance, or that energy=mass times the speed of light quintupled... Your logic is flawed (non-existent) and your conclusion is false. If I pick up a clock, the vibrations generated by my heartbeat move it, even if it's not noticeable. So do the vibrations from motion within the Earth's crust as well as random neutrino and cosmic-ray hits and all the particles HAVE to be moving because they don't have 0K when your not measuring them, which means the particles of the clock are in some way "moving back and forth" due to kinetic energy and definitely due to unnoticeable vibrations that are proven to exist. The term "clock" in relativity, and in physics in general, does not refer to any specific device, or in fact to any device at all, but rather any means, real or idealized, for measuring time. "Time is what clocks measure". So, yes, if you have a physical device that is your "clock" then the elementary particles of which it is composed will each be in some quantum state and that state will not be one of 0 energy even if the clock is at 0K -- not all (in fact no two) fermionic particles in a system, according the Pauli exclusion principle, can be in the same quantum state, so they cannot all have 0 energy. But they can be in the lowest allowable set of states and that is what is meant by absolute zero.
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