Sorry, RC, this is just a matter of terminology, and you're mistaken. Gamma-gamma pair production (two "real" photons) is indeed a real process, albeit a fairly uncommon one in laboratory circumstances. It's most commonly dealt with in astrophysics, where you get collisions between high-energy blazar photons and low-energy starlight photons, which in practice you observe as energy-dependent attenuation of blazar light. If we ever build the International Linear Collider, there's a simple modification which turns it into a photon-photon collider.
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Why is there so much crackpot physics?
- Thread starter Perpetual Student
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Sorry, RC, this is just a matter of terminology, and you're mistaken. Gamma-gamma pair production (two "real" photons) is indeed a real process, albeit a fairly uncommon one in laboratory circumstances. It's most commonly dealt with in astrophysics, where you get collisions between high-energy blazar photons and low-energy starlight photons, which in practice you observe as energy-dependent attenuation of blazar light. If we ever build the International Linear Collider, there's a simple modification which turns it into a photon-photon collider.
Reality Check
Penultimate Amazing
My point (as I emphasis in later posts) is that it is a matter of terminology.
The model that Farsight is using (Is the electron a photon with toroidal topology?) is based on actual pair production. So when he went on about gamma-gamma pair production in this thread, the context was actual pair production making him wrong.
Now we know that this gamma-gamma pair production is actually the Breit-Wheeler process. So the usage of the term is correct - the idea that this process means that electrons and positrons are photons remains a fantasy.
ETA: Whoops - I obviously do not memorize invalid crackpot papers!
The paper actually is talking about gamma-gamma pair production but never actually uses that term or the Breit-Wheeler process. Equation 2 is electron/positron annihilation with an arrow back from the photons to the particles (the Breit-Wheeler process).
Thus it looks like it is pair production that the paper implies is impossible (no extra photon is available).
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Perpetual Student
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Overwhelming evidence? Just another bold-faced bluff -- as are all your posts.
I have examined each of those links; there is no connection to the crackpot notion that an electron is a photon in some kind of a loop.
So, for the third time, show us the QF equation that describes the electron as a photon in a loop. You can't -- just admit it; you have no idea how to structure a QF equation -- a pretend one -- or real one, for that matter. Go take your pretend physics to some ignorant jungle bush man, where you can light a firecracker and make them believe your a god. Everyone here is laughing at you!
Grrrrr -- indeed!
Perpetual Student
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My understanding has been that any process like e− + e+ → γ + γ that can be rendered in a Feynman diagram is reversible by virtue of anti-particles. Is that not true?
(Farsight, this question is for those here who really understand physics, like ben m and RC. Please do not pretend to answer it.)
edd
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It seems rather rude to say ctamblyn wanted to 'do a runner' given the number of times you've posted 'look at the time', doesn't it?
I don't think I need to respond greatly given previous posts have it covered, but call it what you want. Mislabelling it is not an argument against it. I rather like the place you suggest though. I drop in on it now and again but that is due to an unrelated interest.
Kid Eager
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The first problem is the Farsight essentially made up his own meaning for the term "gamma-gamma pair production".
The "pair production" part implies the actual pair production that he has been obsessed abut in other threads (thus the pair production answers).
The entire term means the production of pairs of gamma rays.
What he is actually talking about is the Breit-Wheeler process which is the collision of photons in high intensity laser beams than produce electron/positron pairs.
There is no connection between this process or pair production and Farsight's model which is the Is the electron a photon with toroidal topology? paper which came up over 3 years ago and is fundamentally flawed. This was explained to Farsight in the Relativity+ / Farsight's thread, e.g. OK, I've read the Williamson and van der Mark
paper again. (they should have got a charge of zero for an electron).
Farsight has been blindly denying the science for over three years now!
The paper mentions pair production. The authors and Farsight have no real mechanism where a toroidal topology magically appears and traps a photon. They do draw pretty pictures though!
The first problem with the model is above - it predicts that an electron has no charge. So we can shop there!
The next problem is that their pair production does not need a nucleus and so does not conserve momentum. In fact the paper does not mention the need to interact with a nucleus to conserve momentum at all.
And if we ignore that problem then we have pair production happening spontaneously whenever there are photons with enough energy. This is not observed.
Okay - thanks! Saw the subsequent digression into the photons colliding bit, but from what I looked up, that's not what Pair Production typically refers to.
Interestingly (or perhaps not for you boffins) I also came across a paper where they broke down an electron into two particles, neither of which was a photon. This would appear to kill the loopy photon hypothesis of the electron. See here:
http://www.nature.com/nature/journal/v485/n7396/full/nature10974.html
edd
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Well that's talking about quasi particles, so it's not quite the same kind of thing. A better point would be that the electron engages in weak interactions, so you can have electrons turning into a neutrino and W- particle, or interacting with Z bosons rather than photons (subject to the usual conservation laws).
MINISTERofTRUTH
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Why is there so much crackpot physics?
Perhaps smoking crack and pot is on the uprise.
Perhaps smoking crack and pot is on the uprise.
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I do not mind saying that I do not understand gamma-gamma pair production, and now it turns out that you are more less inventing the term yourself. I trust Ben when he says that it exists, but that the terminology is misleading.
And I would like to add that you are doing us all a favour by providing us with a real-life example of a crackpot who displays all the characteristics of the stereotype. Your bombardment with irrelevant Wikipedia articles whenever you are cornered is particularly illuminating, as is your "blah blah" comments when you are cornered.
I am also fascinated that you actually believe you have the upper hand
ArmillarySphere
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As far as my understanding goes, the two-photon pair production process is simply the time-reversed equivalent of electron-positron annihilation, so any link describing the one automatically applies to the other.
However, since the cross-sections are vastly different, I imagine there's a mathematical difference. I haven't studied QM for far too long to attempt a calculation.
However, since the cross-sections are vastly different, I imagine there's a mathematical difference. I haven't studied QM for far too long to attempt a calculation.
Several posts have been removed to AAH. Do not insult other members, and do not derail threads. Note that the topic of this thread is "Why is there so much crackpot physics?". There is already a thread to discuss Farsights specific claims here.
Replying to this modbox in thread will be off topic Posted By: Cuddles
Actually, Richard Feynman got a Nobel Prize for working out what you think that he rejected.
An elementary particle's propagator is the amplitude for creating a particle in one position and then destroying it in another position. In momentum space, it has a pole at the particle's mass value. It goes to infinity when the magnitude of the 4-momentum equals the square of its mass (or minus the square of its mass, depending on the metric signature one uses).
If you wish to calculate a photon's propagator in a photon-electron system, you start off with a bare photon propagator, then add in the effects of electron interaction. The lowest-order electron interaction is a one-loop diagram:
A photon is created and it turns into an electron and a positron. The two particles then run into each other, making a photon again, and it then gets destroyed.
The next step up is two-loop diagrams. One of them is two electron-positron loops, and the other is one electron-positron loop with the electron and positron exchanging a photon.
If you calculate the strength of the photon propagator from that, it diverges. But RF and others worked out how to make it well-behaved. That is by defining the bare propagator as having a strength with a divergence in the opposite direction, a divergence that cancels out the the calculated divergence. That's what's called renormalization, and it got RF a share of a Nobel Prize.
The same sort of calculation can be done with electrons, with a one-loop electron propagator having the electron emit then re-absorb a photon. Divergences appear here also, and they can be handled in the same sort of way.
Needless to say, other physicists have extended this sort of calculation far beyond photon-electron interactions, far enough to encompass the Standard Model and various proposed extensions and GUT's.
That's not it Robo. I give evidence to support my case, others say they have overwhelming contrary evidence when they don't, and then when I challenge edd to explain a well-known experimental phenomenum and say "Do you think it's magic?" he says "Yep". Then he follows it up with essentially it surpasseth all human understanding. There's no place for that on a skeptics forum, and no place for that in science.
That's not the issue, and note that the experiment predates the theory. Pair production goes back to Carl Anderson in 1932.
I call it science too. Edd called it magic. We do physics to understand the world, not to roll over and give up on understanding.
edd
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Well, I agreed somewhat with my tongue in my cheek to your suggestion. I certainly am ok with going along with
but I don't actually think that's magic. I could also be wrong about what actually happens on very small scales about that, but I don't think that the interactions a particle can engage in give an indication that one particle must have another as its underlying building block. I'm certainly happy to say I don't think we have a better idea of what happens than to say they pop in or out of existence.
I've not given up on understanding, but I'm certainly not drawing the same conclusions about nature as you are, and I'm ready to accept that I might not aesthetically like the answers I get.
godless dave
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Where?
Linking to articles about aspects of the standard model doesn't support your case.
Reality Check
Penultimate Amazing
Farsight, I was pointing out some of your ignorance of the physics involved. Getting back to the OP - your statements do evoke some reasons why there is so much crackpot physics.
There are people who just cannot believe the results of experiments, i.e. dismiss scientific results as just "bumps on graphs" because they have existing beliefs that no experimental data can change.
Then there are the people who only know a part of the science and think that is all of the science. An example are the Electric Universe people who basically ignore the magnetic part of electromagnetism. Or the plasma cosmology people who know the importance of plasma physics in space on small scales and think that applies to cosmological scales.
Then there are the people who just cannot express themselves coherently. They are not true cranks because with a bit of education they get better. But they can be confusing, e.g. by citing references to one phenomena while mentioning another.
W.D.Clinger
Philosopher
Reality Check's signature links to a book review written by Ben Monreal. Generalizing some excerpts by replacing the book's author by X, with italics as in the original:
To consider a broader issue in physics crackpottery, many physics crackpots have an aversion to complicated mathematics, even though it's an essential part of many important theories.
It could simply be that many of them don't understand it, but they give other reasons, like math not being capable of expressing meaning or whatever.
Some physics crackpots do use math, however, if rather simple math: those who attempt to derive values of various fundamental constants, like the ratio of proton to electron masses and the fine structure constant, by mashing together lots of numerical values. Small integers and pi and so forth.
But in the Standard Model, they are not truly fundamental. Most of nucleons' masses come from the kinetic energy of the quarks and gluons that they contain. The electromagnetic interaction is a result of electroweak symmetry breaking, including the value of its interaction strength. Etc.
So one would have to look at what's at GUT energies and quantum-gravitational energies, and even then, that method won't tell us anything.
It could simply be that many of them don't understand it, but they give other reasons, like math not being capable of expressing meaning or whatever.
Some physics crackpots do use math, however, if rather simple math: those who attempt to derive values of various fundamental constants, like the ratio of proton to electron masses and the fine structure constant, by mashing together lots of numerical values. Small integers and pi and so forth.
But in the Standard Model, they are not truly fundamental. Most of nucleons' masses come from the kinetic energy of the quarks and gluons that they contain. The electromagnetic interaction is a result of electroweak symmetry breaking, including the value of its interaction strength. Etc.
So one would have to look at what's at GUT energies and quantum-gravitational energies, and even then, that method won't tell us anything.
Kwalish Kid
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I can see how obtuse moderation on supposedly scientific forums could support crackpot activity.
ctamblyn
Data Ghost
One of those people was, regrettably, Arthur Eddington, though his mathematical ability would easily have surpassed most of the crackpottery we've been discussing around here.
For the benefit of anyone who doesn't know the story, in the 1930s Eddington used a numerological argument to "prove" that 1/α = 136 exactly (at the time, this was consistent with experimental data). He went on to "prove" that the number of protons in the universe must be exactly 136 × 2256.
When experiments showed that the true value was closer to 137, he miraculously discovered that the original proof was mistaken, and came up with another that 1/α was the integer 137.
As more data came in, it became apparent that 1/α is not an integer at all. In fact, according to NIST's CODATA values of the fundamental physical constants, the current recommended value is 137.035999074(44).
That doesn't seem to deter physics crackpots from trying to "derive" α though. There seems to be an irresistible temptation to believe it must be expressible in terms of integers, Euclidean-geometrical arguments, natural logarithms and so on, and that pure reason can reveal the derivation.