![]() |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
![]()
This message is a continuation of the discussion in the thread
'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. This leads to the false belief that an electron's position is smeared out over the orbital, and that the probability function is independent of earlier observations. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. For all higher n, the relative uncertainty becomes smaller, and the classical orbit becomes an increasingly better approximation. This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. The solar system obeys the same physical laws as the atom. There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. Andrew Usher |
#2
|
|||
|
|||
![]()
Andrew Usher wrote:
This message is a continuation of the discussion in the thread 'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. Since when do logic and QM have anything to do with each other? Especially when you use a conventional (classic?) approach? That's like trying to apply the rules of algebra to pig latin. |
#3
|
|||
|
|||
![]()
Andrew Usher wrote:
This message is a continuation of the discussion in the thread 'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Res ipsa loquiter. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. Res ipsa loquiter ad nauseam. [snip[] This explains the solar system, for example, [snip further crap] -- Uncle Al http://www.mazepath.com/uncleal/ (Toxic URL! Unsafe for children and most mammals) "Quis custodiet ipsos custodes?" The Net! |
#4
|
|||
|
|||
![]()
"Andrew Usher" wrote in message
om... This message is a continuation of the discussion in the thread 'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. This leads to the false belief that an electron's position is smeared out over the orbital, and that the probability function is independent of earlier observations. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. For all higher n, the relative uncertainty becomes smaller, and the classical orbit becomes an increasingly better approximation. This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. The solar system obeys the same physical laws as the atom. There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. Andrew Usher Shabby metaphysics, at best. Here's some Gems: Placed properly, classical physics is isn't incorrect: The Hamiltonian of Quantum Mechanics contains all of classical physics. The purpose of the QM wave equation is to place Planck's constant in proper relationship to the classical Hamiltonian. [Old Man] |
#5
|
|||
|
|||
![]() "Andrew Usher" wrote in message om... This message is a continuation of the discussion in the thread 'Neutrino mass'. It is more like a reiteration of your position, already stated in that thread. I admit to not being formally educated in QM. Neither am I. But I try not to criticise things I don't understand. I am nevertheless trying to criticise a belief normally taught in such education. If you're referring to the idea of the electron being "smeared" across the orbital, then it is you who has misunderstood. "In a general paper on quantum mechanics, Schroedinger discusses and rejects the interpretation that a single quantum is somehow phyiscally "spread out" or "blurred" among the different parts of a superposition ." That is what is being taught. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. It is very useful for chemistry and nuclear physics, but it is a model and not meant to be taken as a true picture of the atom. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. This leads to the false belief that an electron's position is smeared out over the orbital, That's *your* false belief. The electron isn't "smeared out over the orbital" (just as Schroedinger's cat isn't alive AND dead). It just doesn't have a position until one has been measured (just as you don't know if the cat is alive or dead until you open the chamber), and then that position is one that is affected by the act of measuring, and is therefore not a true representation of where the electron really was, if indeed it had a position at all. That's why such an innate position is done away with entirely; it is meaningless since it can't be measured without interfering with it. and that the probability function is independent of earlier observations. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. For all higher n, the relative uncertainty becomes smaller, and the classical orbit becomes an increasingly better approximation. What difference would it make? If none, then what is the value of your version? This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. Which is exactly why QM doesn't explain it. The solar system obeys the same physical laws as the atom. Because it looks like the classic atomic model? You're not the first to see the similarity. What happens inside an atom is very different from a solar system. Or do you believe that the sun has a positive charge and the planets a negative charge? There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. |
#6
|
|||
|
|||
![]()
On Fri, 28 May 2004 23:00:20 -0500, "Old Man"
wrote: "Andrew Usher" wrote in message . com... This message is a continuation of the discussion in the thread 'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. This leads to the false belief that an electron's position is smeared out over the orbital, and that the probability function is independent of earlier observations. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. For all higher n, the relative uncertainty becomes smaller, and the classical orbit becomes an increasingly better approximation. This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. The solar system obeys the same physical laws as the atom. There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. Andrew Usher Shabby metaphysics, at best. Here's some Gems: Is anything beyond the equations 'metaphysics' to you? Do you think we should make no effort to actually understand physics? Placed properly, classical physics is isn't incorrect: The Hamiltonian of Quantum Mechanics contains all of classical physics. This is actually what I am saying. The purpose of the QM wave equation is to place Planck's constant in proper relationship to the classical Hamiltonian. [Old Man] Andrew Usher |
#7
|
|||
|
|||
![]()
"Old Man" wrote in message ...
"Andrew Usher" wrote in message om... This message is a continuation of the discussion in the thread 'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. This leads to the false belief that an electron's position is smeared out over the orbital, and that the probability function is independent of earlier observations. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. For all higher n, the relative uncertainty becomes smaller, and the classical orbit becomes an increasingly better approximation. This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. The solar system obeys the same physical laws as the atom. There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. Andrew Usher Shabby metaphysics, at best. Here's some Gems: Is anything beyond the equations 'metaphysics' to you? Should we not try to actually understand the physics? Placed properly, classical physics is isn't incorrect: The Hamiltonian of Quantum Mechanics contains all of classical physics. That this must be so is what I have been saying. The purpose of the QM wave equation is to place Planck's constant in proper relationship to the classical Hamiltonian. [Old Man] Andrew Usher |
#8
|
|||
|
|||
![]() "Andrew Usher" wrote in message om... This message is a continuation of the discussion in the thread 'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. The idea that the Bohr-Sommerfeld orbits are an incorrect and an obsolete model of the atom is in fact quite correct. That approach led to a dead end and was entirely superceded by quantum mechanics about seventy years ago. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. It is in fact a completely useless and misleading idea. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. There is no such thing as a time-independent wave function. A wave is by defnition a function of space and time. The only reason why the orbitals are written as time-independent functions is because each of them has an additional implied factor exp(iEt/hbar), where E is the energy. So the orbitals are actually standing waves. This leads to the false belief that an electron's position is smeared out over the orbital, The probability density for finding the electron at a given position *is* in fact determined by the orbital. and that the probability function is independent of earlier observations. Those two lines carry no meaning that I can unambiguously discern. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. Unless you are trying to be clever by making a statement about the fact that excited states are not stable, I can't follow what you are driving at. For all higher n, the relative uncertainty becomes smaller, The uncertainty relation relating momentum and position errors is independent of the quantum number. and the classical orbit becomes an increasingly better approximation. This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. The solar system obeys the same physical laws as the atom. There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. Yes, the so-calle Rydberg states, with very high quantum numbers, do begin to approximate to the classical situation. This is a consequence of the corespondence principle. Franz |
#9
|
|||
|
|||
![]()
On Sat, 29 May 2004 08:43:34 +0200, "Laura" wrote:
"Andrew Usher" wrote in message . com... This message is a continuation of the discussion in the thread 'Neutrino mass'. It is more like a reiteration of your position, already stated in that thread. I admit to not being formally educated in QM. Neither am I. But I try not to criticise things I don't understand. I am nevertheless trying to criticise a belief normally taught in such education. If you're referring to the idea of the electron being "smeared" across the orbital, then it is you who has misunderstood. "In a general paper on quantum mechanics, Schroedinger discusses and rejects the interpretation that a single quantum is somehow phyiscally "spread out" or "blurred" among the different parts of a superposition ." That is what is being taught. What do you believe we should picture? Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. It is very useful for chemistry and nuclear physics, but it is a model and not meant to be taken as a true picture of the atom. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. This leads to the false belief that an electron's position is smeared out over the orbital, That's *your* false belief. The electron isn't "smeared out over the orbital" (just as Schroedinger's cat isn't alive AND dead). It just doesn't have a position until one has been measured (just as you don't know if the cat is alive or dead until you open the chamber), and then that position is one that is affected by the act of measuring, and is therefore not a true representation of where the electron really was, if indeed it had a position at all. True, as a matter of logic, not physics. That's why such an innate position is done away with entirely; it is meaningless since it can't be measured without interfering with it. and that the probability function is independent of earlier observations. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. For all higher n, the relative uncertainty becomes smaller, and the classical orbit becomes an increasingly better approximation. What difference would it make? If none, then what is the value of your version? That it avoids the implicit belief that the atom obeys different physical laws. This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. Which is exactly why QM doesn't explain it. QM is not necessary to explain it. The solar system obeys the same physical laws as the atom. Because it looks like the classic atomic model? You're not the first to see the similarity. What happens inside an atom is very different from a solar system. Or do you believe that the sun has a positive charge and the planets a negative charge? There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. I think you should read my last paragraph again. Andrew Usher |
#10
|
|||
|
|||
![]()
Franz Heymann wrote:
"Andrew Usher" wrote in message om... This message is a continuation of the discussion in the thread 'Neutrino mass'. I admit to not being formally educated in QM. I am nevertheless trying to criticise a belief normally taught in such education. Although I don't understand the math involved in the conventional approach, I believe that I can understand the basics in terms of logic. The false idea is that the Bohr-Sommerfeld orbits are an incorrect and obsolete model of the atom. The idea that the Bohr-Sommerfeld orbits are an incorrect and an obsolete model of the atom is in fact quite correct. That approach led to a dead end and was entirely superceded by quantum mechanics about seventy years ago. As we know, the idea of fixed orbits is not exactly correct, but that does not make it useless. It is in fact a completely useless and misleading idea. The orbitals are conventionally given as time-independent wavefunctions, and that is held to be the correct description. There is no such thing as a time-independent wave function. A wave is by defnition a function of space and time. The only reason why the orbitals are written as time-independent functions is because each of them has an additional implied factor exp(iEt/hbar), where E is the energy. So the orbitals are actually standing waves. This leads to the false belief that an electron's position is smeared out over the orbital, The probability density for finding the electron at a given position *is* in fact determined by the orbital. and that the probability function is independent of earlier observations. Those two lines carry no meaning that I can unambiguously discern. From the uncertainty principle (which states that particles occupy h^3 in phase space), this can only be strictly true for the 1s orbital. Unless you are trying to be clever by making a statement about the fact that excited states are not stable, I can't follow what you are driving at. For all higher n, the relative uncertainty becomes smaller, The uncertainty relation relating momentum and position errors is independent of the quantum number. and the classical orbit becomes an increasingly better approximation. This explains the solar system, for example, where the quantum numbers are very, very large and thus quantum effects are unobservable. The solar system obeys the same physical laws as the atom. There is one important difference, though: the electrons interact with each other to such an extent that their orbits would be chaotic even with the pure Bohr-Sommerfeld orbits. Right. Unless they all have the same direction magnetic field at the same time. The electrons must all lie in concentric, co-rotating rings for them not to interfere with each other yet still exert over the volume: http://www.petcom.com/%7Ejohn/H.GIF http://www.petcom.com/%7Ejohn/He.GIF http://www.petcom.com/%7Ejohn/Li.GIF http://www.petcom.com/%7Ejohn/Be.GIF John |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
electron radius =1.498754637*10^-22 meters | peter | Astronomy Misc | 7 | January 31st 04 10:27 PM |
Milky Way's Big Bang | Giovanni | Astronomy Misc | 30 | January 6th 04 10:32 AM |
Gravitation and Maxwell's Electrodynamics, BOUNDARY CONDITIONS | [email protected] \(formerly\) | Astronomy Misc | 273 | December 28th 03 10:42 PM |
GravityShieldingUpdates1.1 | Stan Byers | Astronomy Misc | 2 | August 1st 03 03:02 PM |