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Qkslvr
Pooh-Bah
Reged: 06/23/06
Posts: 1052
Loc: NE Ohio, US
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Quote:
What's not mentioned here is that given enough external pressure, an electron CAN be forced to merge with a proton, giving up a W-particle and creating a neutron. This is what happens during the creation of a neutron star. So there's more than just probability at work here -- there are also nuclear forces. In this case I believe it is the weak force that keeps protons and electrons apart.
Just the thing I was looking for Dave, Thanks.
I took this and looked it up in one of my physics books, it described this as "reverse Beta Decay". Now Protons are made of 2 Up quarks and one Down quark, and a Neutron is 2 Down Quarks and one Up quark. So while not necessarily directly this means that Electrons captured by a proton causes a Up quark to become a Down quark.
But all this leads me to my next question, Does Beta decay really mean that the atom captured a W- particle to initiate the decay? Also W particles have a Charge of +/-1, Does that require 2 W particles? One to cancel the electrons charge and one to cancel the protons charge?
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Mike
N8/CG-5/40D
Coming sometime/Maybe FrankenRebel
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Qkslvr
Pooh-Bah
Reged: 06/23/06
Posts: 1052
Loc: NE Ohio, US
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Quote:
Just because the math is impossible to solve does not mean the electron does not have a position. For example, an integral can represent a real physical property and yet be impossible to solve (I don't have a specific example to offer, but I believe this is common knowledge for anyone having completed integral calculus). Just because the math describing it is impossible to solve does not mean the real physical property (such as position) cannot exist.
While I understand your question, from what I've read on this, it isn't a matter of not knowing enough to solve the equation, It's that the electron doesn't even exist as a real particle until it's measured.
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Mike
N8/CG-5/40D
Coming sometime/Maybe FrankenRebel
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Pess
(Title)
Reged: 09/12/07
Posts: 1910
Loc: Toledo, Ohio
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Quote:
Does this mean that the images of individual atoms on a surface taken using a scanning electron microscope are in fact views of the outside of the probability cloud? I thought that the orbital electrons were scattering the incoming electron beam and reflecting part of it to the imaging detectors.
With a STM (Scanning tunneling Microscope) there are no 'views'.
All solids are essentially 'walls of electrons'. When you push against your bathroom wall the resistance you feel is the repulsiveness of electron clouds of the wall repelling the like charged electron clouds that make up your hand.
The tip (stylus) of the STM is sharpened to a single atom.
When this tip is lowered close to a sample, electrons in the sample surface atoms can 'tunnel' across the vacume and into the stylus.
Remember that since the electrons can be anywhere, a few will effectively 'appear' in the stylus (tunnel) and be conducted away-- creating an electric current.
The intensity of this current is directly proportional to how close the stylus tip is to the sample...ie: the closer the stylus tip the more electrons can tunnel into the tip within a given time.
Graphing this current as the tip moves across a set distance from the sample, a topographical 3D 'map' of the sample surface can be drawn.
So in a way you are drawing or mapping the outer electron shell of the atomic lattice work of the samples surface.
I think of the best analogy is to think of it like putting a tissue paper over a sample and making a 'rubbing' of it by using the side of a pencil lead.
The nucleus of the atoms making up the sample are far inside their electron clouds and are not subject to tunneling anyways..
The technology that allows STM's can also be used to pick up loose atoms and place them on a substrate by the simple expediency of turning the power to the stylus on/off as required.
IBM first accomplished this with Xenon atoms.
Neutron stars are essentially a star that has collapsed so far that the electrons and protons of its constituent atoms are crushed together to form neutrons plus neutrinos that zip away.
Pesse (A hockey puck sized piece of neutron star would make a great paper weight.) Mist
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12" RCX400
WILLIAM OPTICS 110mm APO ZENITH STAR refractor
Custom Wyorock focuser for refractor
Douglas Schwan DC
Befuddled observer, bewildered student, bemused teacher.
Purveyor of cognitive dissonance.
Todays Quote: "Answers are worthless unless the proper question has been asked."
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HiggsBoson
scholastic sledgehammer
Reged: 02/21/07
Posts: 796
Loc: Kal-li-fornia
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I brought up the photoelectric effect because Tagyon was asking about thinking of light as a wave vs. a particle. The photoelectric effect was one of the key findings which made thinking of light as a particle even possible.
In the photoelectric effect increasing the brightness of the light increased only the number of electrons not the energy of them. This suggested that the photons all contain the same amount of energy and that it is quantized. This in no way suggest that a photon is a little ball of stuff. Photons are discrete things that are described by a wave function. In this manner they are similar to electrons. This difference is one is mass-less while the other has non-zero rest mass.
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This is where the model becomes impossible to solve.
Just because the math is impossible to solve does not mean the electron does not have a position. For example, an integral can represent a real physical property and yet be impossible to solve (I don't have a specific example to offer, but I believe this is common knowledge for anyone having completed integral calculus). Just because the math describing it is impossible to solve does not mean the real physical property (such as position) cannot exist.
I misspoke! The math is hard to do and sometimes impossible to solve.
Throughout the course of this conversation I have tried to limit my pronouncements to results that I actually understand.(1) The case of the universe that contains one H atom with one electron in the ground state is a case where I have a handle on the math. The more I vary from that case the greater than probability that I will commit an error. Given the non-intuitive nature of this subject I am concerned about how thin the ice gets when one speculates.
A few days ago I reviewed the single H atom in the universe and I recalled that the solution is dependant upon the electric field created by the proton. If we consider other objects in the universe I must include them explicitly or argue that they have no effect reducing the problem to the original case. I do not argue that the math can not be done only that I have not done it and do not wish to speculate about the solution of cases that I have not worked or at least studies in books.
While the solutions always exist I am not capable of solving the cases of interest here. I am clinging to the ground state because it shows that the electron is not moving and does not have a location to find(2)! This case looks wave-like. All other cases are built from wave-like cases and some look like particles. I am attempting to show that the simplest behavior is wave-like and that this description is sufficient to explain all observed electron behavior. Calling the electron or photon a particle under certain conditions adds nothing to its mathematical description. The math is wave-like. All particle descriptions are approximations, useful but approximations none the less.
If I were to describe the path of an electron in a Television Video Tube Display. I could model the electron as a little ball with a negative charge. I could compute the kinetic energy of the electrons and show how they would move with sufficient accuracy to make the ‘beam’ scan the pixels of the tube with sufficient accuracy to explain how I see the text that I write here.(3) A complete description would require that someone, not me, write down the potential as seen by the electron and jam that bad boy into Schrödinger’s equation and turn the crank. This potential would include gravity and nearby electric and magnetic fields. This would still be an approximation due to the omission of relativistic considerations.(4)
Summary:
I argue that the wave description is sufficient to gain a complete description of all that can be known about the electron. Einstein spend about 30 years hating this seeking a better description.
1) A profound limitation.
2) This creates an odd mental image of a universe consisting of one proton and electron sitting in a ground state hydrogen configuration plus one physicist clinging to the atom for fear that he will lose track of it in an otherwise empty and dark universe.
3) Yes, I am still using a Cathode Ray tube. ( Holding my head down in shame )
4) Yes, this mixture of Quantum and Relativity can be done for some limited cases. One must step carefully around a ridiculous number of infinities that will frustrate one’s efforts to gain useful results.
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Michael
ATM: 6" F/9 Newtonian Travel Scope
ATM: 12.5" F/4.5 Real Soon Now...
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Dane B
super member
Reged: 02/23/08
Posts: 120
Loc: Seattle, Wa
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Quote:
In the photoelectric effect increasing the brightness of the light increased only the number of electrons not the energy of them. This suggested that the photons all contain the same amount of energy and that it is quantized. This in no way suggest that a photon is a little ball of stuff.
"This suggested that the photons..."
Do you realize that a photon is a particle?
When I say "particle" you think "little ball of stuff". In doing so you are making a conceptual error which leads you to misunderstand and mischaracterize my statements.
The original double-slit experiment with light, performed in the early 1800s, yielded an interference pattern suggesting light was a wave. Later that century Maxwell predicted light was an electromagnetic wave, and before the end of the century this prediction was confirmed. After a century of wave theory development the particle theory of light appeared vanquished.
The observation of the photoelectric effect in the early 1900s is responsible for bringing back the particle theory of light. This effect, and Einstein's explanation of it, gave experimental and theoretical support to the idea of a photon for the first time in modern history.
So for you to shrug off the effect as something easily explained by the properties of photons is to miss the point entirely - photons and their properties were not understood before this effect was studied!
Because of the photoelectric effect light could be thought of as a particle. Not a classical particle of course, but I'm not the one mistaking a particle view of light as necessarily being classical.
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Meade DS-2130AT w/ GOTO
Nikon 12x50AEs
Without judgement what would we do? We would be forced to look at ourselves...
-Death
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Pess
(Title)
Reged: 09/12/07
Posts: 1910
Loc: Toledo, Ohio
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Quote:
.............. So there's more than just probability at work here -- there are also nuclear forces. In this case I believe it is the weak force that keeps protons and electrons apart.
Hmmm, lost me here.
The term 'probability cloud' is just another term for wave front.
The wave duality of the electron is the entire basis for the existence of the valence shell...otherwise the electron would spiral in.
Of course electrons, in t he form of plasma, can be accelerated into and caused to collide with atomic nuclei..but here the wave front is infused with so much energy it disrupts the nucleus.
Classical theory can work in some situations such as one billiard ball hitting another analogy but one must resort to quantum mechanical theory to pick up the slack.
Pesse (Is the center of a blackhole singularity one giant quark?) Mist
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12" RCX400
WILLIAM OPTICS 110mm APO ZENITH STAR refractor
Custom Wyorock focuser for refractor
Douglas Schwan DC
Befuddled observer, bewildered student, bemused teacher.
Purveyor of cognitive dissonance.
Todays Quote: "Answers are worthless unless the proper question has been asked."
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HiggsBoson
scholastic sledgehammer
Reged: 02/21/07
Posts: 796
Loc: Kal-li-fornia
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Dane
The two slit experiment suggest that light is a wave. The photoelectric effect suggest that it is a particle. Later we recognized that it is quantized and best described by a wave-function.
Electrons behavior is generally consistent with a particle and was later observed to behave like a wave a low energies. Later we recognized that it is best described by a wave-function.
The phrase particle-wave duality is the name given to the discussion on this matter at the end of the 19th century. Now we understand that wave mechanics provides our best understanding of both these types of objects. We know call both ‘particles’ because the word ‘wavlicales’ is awkward. In quantum electrodynamics both electrons and photons are described by the same equation. The difference is the mass term is set to zero with the photon. The charge term is multiplied by the mass term hence photons are charge-less.(1)
When modern physicist refer to a particle they simply understand that this refers to something described by a wave-function and does not imply a ‘little ball of stuff’ in the classical sense.
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Do you realize that a photon is a particle?
While the answer is yes, I do not understand the intent of the question. The issue is weather you intended the classical meaning of particle or the QM jargon which is common usage among physicist. The Standard Model of Particle physics includes mass-less particles such as photons and gluons.
1. Since charge determines the coupling of something to photons, the fact that the photon has no charge implies that photons do not interact with each other. Also since the sign of the charge determines if one is dealing with a particle or its anti-particle the charge-less photon becomes its own anti-particle.
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Michael
ATM: 6" F/9 Newtonian Travel Scope
ATM: 12.5" F/4.5 Real Soon Now...
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Dane B
super member
Reged: 02/23/08
Posts: 120
Loc: Seattle, Wa
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When modern physicist refer to a particle they simply understand that this refers to something described by a wave-function and does not imply a ‘little ball of stuff’ in the classical sense.
Are you being facetious? I thought I acknowledged this in my last post. Particle does not mean little ball of stuff, but you seem bent on speaking to me as if I think this way.
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Do you realize that a photon is a particle?
While the answer is yes, I do not understand the intent of the question.
You were making the argument that the photoelectric effect is not evidence of a particle nature of light; but the photoelectric effect provided the experimental and theoretical evidence for photons. Photons are particles. Thus the photoelectric effect is evidence of a particle nature of light.
Again, if you are tempted to lecture me on how photons aren't a little ball of stuff save your time. This is nothing new to me. I haven't at any point in this discussion confused the concepts of particles and little balls of stuff. You are the only person talking about little balls of stuff.
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Meade DS-2130AT w/ GOTO
Nikon 12x50AEs
Without judgement what would we do? We would be forced to look at ourselves...
-Death
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HiggsBoson
scholastic sledgehammer
Reged: 02/21/07
Posts: 796
Loc: Kal-li-fornia
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Dane
I am sorry if I misunderstood you. I did not intend to suggest that the photoelectric effect is not indicative of the ‘particle’ nature of light. In fact I assert just the opposite in the second sentence of the post to which you replied. It is unfortunate that in this medium we must communicate without the feed back of seeing the face of the other person or even the ability to see a head nod of understanding. I was concerned that you did not understand the difference between the meaning of the word particle as used by physicist and the ‘little ball of stuff’ that I refer to as the classical definition due to your question which I did not understand.
Additionally I am mindful of others who do not post are reading this thread and I try to explain myself as clearly as possible for the benefit of those who do not know the subject as well as you do.
I am sorry about the misunderstanding. I will attribute it to jet lag.
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Michael
ATM: 6" F/9 Newtonian Travel Scope
ATM: 12.5" F/4.5 Real Soon Now...
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 10438
Loc: Amargosa Valley, NV, USA
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Let's not let mis-communication imply personal slight. If we must assume anything, let's assume the best of intentions on the part of the other, and respond in kind.
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"S.O.E." (Sauron's Other Eye) 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Next Project: The "Eye of Sauron" Observatory!
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Qkslvr
Pooh-Bah
Reged: 06/23/06
Posts: 1052
Loc: NE Ohio, US
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All of this chatting about photons coupling to electrons and such, reminds me that we all know what macro scale couplers look like, Radio Antennas.....
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Mike
N8/CG-5/40D
Coming sometime/Maybe FrankenRebel
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