1 Sylvia Else | An open letter to Mr. Ross A. Finlayson | Tuesday 17 December 2019 |
2 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Tuesday 17 December 2019 |
3 pats | Re :An open letter to Mr. Ross A. Finlayson | Tuesday 17 December 2019 |
4 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Wednesday 18 December 2019 |
5 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Friday 20 December 2019 |
6 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Friday 20 December 2019 |
7 Ross A. Finlayson | Re :An open letter to Mr. Ross A. Finlayson | Friday 20 December 2019 |
8 Nicolaas Vroom | Re :An open letter to Mr. Ross A. Finlayson | Monday 23 December 2019 |
9 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Tuesday 24 December 2019 |
10 Nicolaas Vroom | Re :An open letter to Mr. Ross A. Finlayson | Thursday 26 December 2019 |
11 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Friday 27 December 2019 |
12 Ehren Bates | Re :An open letter to Mr. Ross A. Finlayson | Friday 27 December 2019 |
13 Nicolaas Vroom | Re :An open letter to Mr. Ross A. Finlayson | Monday 30 December 2019 |
14 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Friday 4 January 2019 |
15 Nicolaas Vroom | Re :An open letter to Mr. Ross A. Finlayson | Saturday 5 January 2019 |
16 Nicolaas Vroom | Re :An open letter to Mr. Ross A. Finlayson | Tuesday 8 January 2019 |
17 Odd Bodkin | Re :An open letter to Mr. Ross A. Finlayson | Tuesday 8 January 2019 |
18 Nicolaas Vroom | Re :An open letter to Mr. Ross A. Finlayson | Wednesday 9 January 2019 |
19 Odd Bodkin | Re :An open letter to Mr. Ross A. Finlayson | Wednesday 9 January 2019 |
20 kenseto | Re :An open letter to Mr. Ross A. Finlayson | Wednesday 9 January 2019 |
21 Ross A. Finlayson | Re :An open letter to Mr. Ross A. Finlayson | Thursday 10 January 2019 |
22 Nicolaas Vroom | Re :An open letter to Mr. Ross A. Finlayson | Sunday 13 January 2019 |
23 Odd Bodkin | Re :An open letter to Mr. Ross A. Finlayson | Sunday 13 January 2019 |
24 tjrob137 | Re :An open letter to Mr. Ross A. Finlayson | Tuesday 15 January 2019 |
25 Chuck Oberwise | Re :An open letter to Mr. Ross A. Finlayson | Wednesday 16 January 2019 |
26 Thomas Heger | Re :An open letter to Mr. Ross A. Finlayson | Wednesday 16 January 2019 |
An open letter to Mr. Ross A. Finlayson
169 posts by 18 authors
https://groups.google.com/forum/?fromgroups=#!topic/sci.physics.relativity/Vzr4XFUJIO4
Keywords=169 posts by 18 authors
> |
I have truly enjoyed reading Mr. Finlayson’s posts to this forum. He certainly lives up to his boast “I consider > myself a pro-relativist, as a means”. He has a command of the subject matter that is unmatched in this forum; > which is quite obvious from the hands-off attitude that Dono, Bodkin, et al have adopted towards him. He > documents well and writes even weller. He slings the Latin better than any previous Latin slinger. His > paraconsistent logic is para-flawless. And he loves to hate on the muons as much as I. But this new man > Finlayson has come too far, too fast for my tastes. As astonishing an admission as it might seem, I believe him > to be threatening my primacy as the top relativity slayer around these parts.
Therefore, in order to re-establish my title (or to finally lose it once and for all) I do hereby challenge Mr. > Ross A. Finlayson to a dual as to which of us can devise the most outrageous and hilarious reductio ad absurdum > argument against Relativity, Special or General. Do you accept sir? (I hereby select Mitch as my second.) |
Alleged proofs of the falsehood of relativity posted to this group can mostly be categorised as:
A) Assume it's true, and show that this leads to a contraction.
So far, all such attempts have contained errors.
B) Assume that it's false, and show that this is consistent with its being false.
Why anyone thinks this says anything about relativity is beyond me.
C) Totally incomprehensible.
Speaks for itself.
Presumably your intent is that the argument fall within A, and that it will indeed contain at least one error, since if it were a valid argument, it would be neither hilarious nor outrageous.
I don't see how one can objectively judge either how outrageous, or how hilarious, such an argument is, much less compare one combination of such with another. Your proposal does not identify the criteria to be applied.
It doesn't even state who will do the judging.
Sylvia.
> | Alleged proofs of the falsehood of relativity posted to this group can mostly be categorised as: A) Assume it's true, and show that this leads to a contraction. So far, all such attempts have contained errors. |
Yes. For this to succeed one must also show that Euclidean geometry is internally inconsistent, and that real analysis is internally inconsistent, or show an error in the proofs that the math of SR is as self-consistent as they are.
Nobody who claims SR is "inconsistent" has even recognized the need to do that.
(That's a self-fulfilling prophecy: anyone who recognizes that need already knows that SR is self-consistent.)
> | [... other ways of attempting to show SR is inconsistent] |
Yes, none of those silly attempts succeed, either.
Tom Roberts
> | On 12/16/19 10:15 PM, Sylvia Else wrote: |
> > | Alleged proofs of the falsehood of relativity posted to this group can mostly be categorised as: A) Assume it's true, and show that this leads to a contraction. So far, all such attempts have contained errors. |
> |
Yes. For this to succeed one must also show that Euclidean geometry is internally inconsistent, and that real analysis is internally inconsistent, or show an error in the proofs that the math of SR is as self-consistent as they are. Nobody who claims SR is "inconsistent" has even recognized the need to do that. (That's a self-fulfilling prophecy: anyone who recognizes that need already knows that SR is self-consistent.) |
> > |
[... other ways of attempting to show SR is inconsistent] |
> |
Yes, none of those silly attempts succeed, either. Tom Roberts |
Einstein’s theory of relativity is a theory in crisis. Of those who actually study it, approximately half come away doubting its validity in spite of the experimental evidence. This situation can’t be entirely due to misunderstanding the theory. Newton’s three laws of motion, the ideal gas law, Coulomb’s law, etc. generate nowhere near as much controversy. Clearly something somewhere is amiss in the world of Relativity.
The Theory of Relativity nearly died in infancy when it was learned in 1907 that it was useless for describing physical phenomena in non-inenertial frames of reference. And what possible use can a theory spoiled by gravity have in a universe that is permeated by gravity. Einstein’s patch for this glitch came to be known as the theory of General Relativity. General Relativity is meant to provide a glitch-free arena in which Special Relativity can successfully operate in the presence of gravity.
But does Einstein’s General Relativity actually fix Einstein’s Special Relativity? For instance, below is described a perfectly plausible physical situation in which Relativity is asked to calculate two very simple, simultaneous and equal scalar quantities—quantities that are easily calculated everyday by engineers, students and scientists where space and time are separate entities. While the same calculations in relativistic space-time have proven to be absolutely and constitutionally incapable of providing consistent values for these two scalars.
Task: calculate in newtons the magnitudes of the centrifugal force and the gravitational force observed to be acting on the Earth as it orbits the Sun, by a distant observer traveling at .9c relative to the Solar System along the line that is collinear with the Sun’s axis of rotation. And please show us your work just for the fun of it. Thanks.
In consideration of the foregoing, is it finally time to carefully scrutinize the experimental evidence for relativity? Here again we find much controversy.
> | Einstein’s theory of relativity is a theory in crisis. |
Not really, but it depends somewhat on what you mean. If you mean SPECIAL relativity in the experimentally-reachable domain today, then you are flat-out wrong. If you mean SR beyond that domain, then it is not a "crisis", it is merely the usual issue of not being omniscient. If you mean GENERAL relativity, then it is not really GR that is in crisis, but rather all of fundamental theoretical physics -- we DON'T KNOW whether it is GR, QM, or both that needs to be changed, we only know that they are incompatible. We also know that the standard model [#] is not self-consistent at some energy higher than our experiments can reach today, so it is not at all inconceivable that it is QM that must change the most, not GR. But GR is not a quantum theory, so it also seems likely that it must be replaced with something else, generically called "quantum gravity" but currently unknown.
[#] The standard model is the best model we have of quantum phenomena and the behavior of elementary particles.
> | Of those who actually study it, approximately half come away doubting its validity in spite of the experimental evidence. |
Just making stuff up and pretending it is true is USELESS.
There have been 1000 - 1800 Ph.D. in physics awarded in the U.S. each year (1972-2017), many more in other countries, and EVERY ONE of them understands SR without "doubting its validity". Some fraction of them understand GR as well, without you fantasized doubts. This COMPLETELY DWARFS the thiny number of vocal crackpots who do indeed doubt the validity of relativity, without understanding it.
> | [... many more unsubstantiated claims, and much nonsense] |
You need to come out of your fantasy world and join the real world. Fantasies and made-up "statistics" are USELESS.
Tom Roberts
> | The central dogma of physics is fair causality, interpreted with the scientific method. |
I have no idea what your "fair" means, but causality as a central tenet of physics died with quantum mechanics. Of course it was outrageously ambiguous long before that.
Today what physicists mean by "causality" is merely the restriction of things that can affect what happens at a given event to that event's past lightcone (including its interior). More accurately, that is called the "causal structure of spacetime".
Tom Roberts
> | Let's be clear that any "violations of causality" are _only_ hypothetical, |
This is just plain not true. The decays of unstable particles are not "caused" by anything. They most definitely are NOT "hypothetical" and are observed every day.
There are many other phenomena that can be described only via statistical techniques. For instance, when two protons collide with energy > 1 TeV, the result can be any one out of millions of different final states. Which one actually happens is not "caused" by anything.
> | [... more nonsense] |
Tom Roberts
> | On 12/20/19 12:30 PM, Ross A. Finlayson wrote: |
> > | Let's be clear that any "violations of causality" are _only_ hypothetical, |
> |
This is just plain not true. The decays of unstable particles are not "caused" by anything. They most definitely are NOT "hypothetical" and are observed every day. There are many other phenomena that can be described only via statistical techniques. For instance, when two protons collide with energy > 1 TeV, the result can be any one out of millions of different final states. Which one actually happens is not "caused" by anything. |
> > |
[... more nonsense] |
> |
Tom Roberts |
Radioactive isotopes eventually decay, to, stabler isotopes, in deep space in a vacuum.
(There's an ongoing consideration that terrene iron Fe sits in the middle of radioactive stability. https://en.wikipedia.org/wiki/Isotopes_of_iron )
That is, radioactive isotopes in neutron bombardment often transmute to elements with higher atomic weight, but, such high energy neutron bombardment is not a usual condition in deep space in a vacuum, where there are effectively no contributions to the field effects from any other system.
Here unstable or transient particles besides, a.k.a. "exotic" "particles", are part of the states of systems that have these intermediate particles as what are the decay products of high-energy reactions, as they are, for their natural tendency to equilibriate (to lower energy states as what energetic states have a tendency to change, then for naturally the symmetric and restitutive reaction for stability).
In particle theory everything's a particle. Transition states over time have them be one particle or another.
When talking about single-valued results (eg at the detector) in multi-valued systems (eg, over and past the particle's sum-of-histories in its transport as a wave), the methods to arrive at single-valued results are usually very effective and sound in the resulting match of measurement to expectation.
Decay of un-stable particles is be-cause they're un-stable.
(This is a usual principle of least action, that stable particles are stable.)
In no way ever does any real thing ever "violate causality".
I.e., if it really seems to: there theory would be one of the varieties of "wrong" (of "the" laws of physics, constant, consistent, complete, and concrete).
Causality is built into the scientific method, with falsifiability as about theory's cause.
Of course, any theory has that, of hypothetical theories, there are other theories where what it has so: are not so. The suitability of "a theory" for science with reproducibility has that breaking the theory is breaking the theory (or model).
I'll certainly agree that "hidden variables" are implicit in probabilistic theories with random variables and unknown distributions.
(I.e., that's rather the point.)
The sampling, observation, and measurement effects are of aptly more than one cause, in all the unknowns, besides as that for one unknown there's only one cause.
> | On 12/20/19 12:30 PM, Ross A. Finlayson wrote: |
> > | Let's be clear that any "violations of causality" are _only_ hypothetical, |
> |
This is just plain not true. The decays of unstable particles are not "caused" by anything. They most definitely are NOT "hypothetical" and are observed every day. |
Particle decay in https://en.wikipedia.org/wiki/Particle_decay is described as: "Particle decay is the spontaneous process of one unstable subatomic particle transforming into multiple other particles."
Radioactive decay in https://en.wikipedia.org/wiki/Radioactive_decay as: "Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation."
Of specific reading are paragraph 7 "Changing decay rates" and par 8 "Theoretical basis of decay phenomena" You claim "that the decay of a particularly unstable particle has no cause" I would claim "that the cause of the decay of a particularly unstable particle is not known, but most probably is triggered by other particles"
> | There are many other phenomena that can be described only via statistical techniques. For instance, when two protons collide with energy > 1 TeV, the result can be anyone out of millions of different final states. Which one actually happens is not "caused" by anything. |
Rutherford scattering in https://en.wikipedia.org/wiki/Rutherford_scattering
is described as:
"However, the intriguing results showed that around 1 in 8000 alpha particles
were deflected by very large angles (over 90°), while the rest passed through
with little deflection.
From this, Rutherford concluded that the majority of the mass was concentrated
in a minute, positively-charged region (the nucleus) surrounded by electrons."
What this means that results of certain collision experiments can be very significant.
Generally speaking, before you play a ball in a game of snooker it can not
be predicted in advance which ball will be moved and which not.
After you played this will be known and which ball caused a different ball
to move.
The actual result depends on the force, position and angle involved of the
initial strike. The total configuration of all the balls in the game
is also important.
What this means that if you want to actually win a game you must be an
experienced player.
Nicolaas Vroom
> | I would claim "that the cause of the decay of a particularly unstable particle is not known, but most probably is triggered by other particles" |
Such GUESSES are useless. We do know experimentally that no known particles induce decays (if they did they would not be called "decays"). We also know that if any "extra" particle does induce what we call a particle decay, then it must have energy and momentum consistent with zero, because particle decays are observed to conserve 4-momentum.
> | [...] snooker [...] |
That is a deterministic but chaotic system. That's QUITE DIFFERENT from a quantum system (which is not deterministic).
Tom Roberts
> | By particle decay I mean pions, muons, and all the unstable particles listed in the PDG handbook. Nuclear decays cannot be measured nearly so precisely, and some are ambiguous: electron capture is clearly not a decay of the nucleus but is a decay of the atom, etc. |
Your original claim is
> | The decays of unstable particles are not "caused" by anything. |
Nicolaas Vroom
> | Your original claim is |
>> | The decays of unstable particles are not "caused" by anything. |
> | But if that is the case, can they be described by Feynman diagrams? |
Certainly. Google is your friend.
Tom Roberts
> | On 12/26/19 1:32 PM, Nicolaas Vroom wrote: |
>> | Your original claim is |
>>> | The decays of unstable particles are not "caused" by anything. |
>> | But if that is the case, can they be described by Feynman diagrams? |
> |
Certainly. Google is your friend. |
google is evil.
> | On 12/26/19 1:32 PM, Nicolaas Vroom wrote: |
> > | Your original claim is |
> >> | The decays of unstable particles are not "caused" by anything. |
> > | But if that is the case, can they be described by Feynman diagrams? |
> |
Certainly. Google is your friend. Tom Roberts |
I did a google search with: decay unstable particle Feynman diagram One of the results was this link: http://www.physbot.co.uk/particle-physics.html
At roughly 50% of this document there is a discussion about: Annihilation = When a particle and antiparticle meet, converting their mass into energy. Pair production = With enough energy, a photon can turn into a particle/ anti-particle pair both involve an e+ and an e- particle. The question is what do they mean with energy. IMO it always has to do with the state/condition of something, in this case the state of a photon.
Specific the description of pair production is interesting because this means, that to cause pair-production, a certain amount of energy has to be added to the state of an existing photon. So my guess is that maybe two photons are involved.
Almost at the bottom of this document 7 Feynman diagrams are discussed. Specific of interest are the Feynman three diagrams 3, 4 and 6. Diagram 3 shows positron decay, which is the subject of this discussion. The reason why I selected these 3 examples is because of the left side (which in all cases involve a p and an n particle) is the same but the right side not. The question is what causes one of these three options to happen? Just above two different concepts are discussed: Fundamental forces, which mention forces, and Conservation Rules: In quantum mechanics (and particle physics) many values must be 'conserved' for an interaction to make sense e.g. in thermodynamics energy is always conserved, it is never created (out of nothing) or destroyed.
My best guess "what causes one of these three options to happen?" are photon interaction.
Nicolaas Vroom
> | The question is what do they mean with energy. |
This is particle physics, in which "energy' ALWAYS applies to an object, and is the time component of its 4-momentum projected onto the inertial frame of interest (almost always the lab frame).
> | Specific the description of pair production is interesting because this means, that to cause pair-production, a certain amount of energy has to be added to the state of an existing photon. So my guess is that maybe two photons are involved. |
Your guess is wrong. You SHOULDN'T need to guess, you ought to be able to READ about this and know what it is. You chose a poor webpage [#].
"Pair production" means a single photon interacts with a heavy charged particle (nucleus) to produce an e+ e- pair (the nucleus acts as a momentum sink, because the bare interaction cannot conserve 4-momentum by itself -- it only appears in higher-order diagrams than your referenced webpage shows [#]). There is a single photon in the initial state, and it must start out with sufficient energy to be above the energy threshold for this interaction. No "adding" is involved -- indeed it simply is not possible to "add" energy to a photon, there can only be interactions with it, which possibly create a new, higher-energy photon.
[#] That webpage shows impossible "Annihilation" and "Pair Production" diagrams. Some diagrams on that webpage are mislabeled, and some are never observed. That webpage is intended for beginning students, and is not a reliable source for details.
> | The reason why I selected these 3 examples is because of the left side (which in all cases involve a p and an n particle) is the same but the right side not. The question is what causes one of these three options to happen? |
That is a random process with multiple possible outcomes. No "cause" is present in the theory.
NOTE: one reads such diagrams from initial to final state; these were drawn to be read bottom to top, not left to right.
> | My best guess "what causes one of these three options to happen?" are photon interaction. |
Again, you SHOULDN'T need to guess, you can READ about this.
Photon interactions are involved, but are not "causes". In quantum phenomena the notion "cause" simply does not apply.
> | On 12/30/19 9:39 AM, Nicolaas Vroom wrote: |
> > |
Specific the description of pair production is interesting because this means, that to cause pair-production, a certain amount of energy has to be added to the state of an existing photon. So my guess is that maybe two photons are involved. |
> |
Your guess is wrong. You SHOULDN'T need to guess, you ought to be able to READ about this and know what it is. You chose a poor webpage [#]. |
Remember I 'asked' you to show me a relevant webpage.
> |
"Pair production" means a single photon interacts with a heavy charged
particle (nucleus) to produce an e+ e- pair (the nucleus acts as a
momentum sink, because the bare interaction cannot conserve 4-momentum
by itself -- it only appears in higher-order diagrams than your
referenced webpage shows [#]). There is a single photon in the initial
state, and it must start out with sufficient energy to be above the
energy threshold for this interaction. No "adding" is involved -- indeed
it simply is not possible to "add" energy to a photon, there can only be
interactions with it, which possibly create a new, higher-energy photon.
[#] That webpage shows impossible "Annihilation" and "Pair Production" diagrams. Some diagrams on that webpage are mislabeled, and some are never observed. That webpage is intended for beginning students, and is not a reliable source for details. |
(The webpage also discusses concepts like E^2, which I found rather tricky.)
Please try this video: https://www.youtube.com/watch?v=hk1cOffTgdk It is from Fermilab: "Fans of particle physics often encounter a series of doodles called Feynman diagrams. These mystifying scribbles were invented by Richard Feynman and they encode information on how particle physics collisions unfold. But they have an even deeper significance. In this video, Fermilab’s Dr Don Lincoln gives you a peek into the deeper meaning of these important scientific pictograms."
This document discusses specifically the scattering of two photons. These scatterings can be very complicated because many photons can be involved. So my guess above is not that strange.
> > | The reason why I selected these 3 examples is because of the left side (which in all cases involve a p and an n particle) is the same but the right side not. The question is what causes one of these three options to happen? |
> |
That is a random process with multiple possible outcomes. No "cause" is present in the theory. NOTE: one reads such diagrams from initial to final state; these were drawn to be read bottom to top, not left to right. |
Dr Don goes from left to right.
> > | My best guess "what causes one of these three options to happen?" are photon interaction. |
> |
Again, you SHOULDN'T need to guess, you can READ about this. |
Maybe I should have written: "How do we explain which of these three options to happen"
> | Photon interactions are involved, but are not "causes". In quantum phenomena the notion "cause" simply does not apply. |
Maybe it is possible by means of different experiments to select the outcome which of the three possibilities will happen. If that is the case you are closer to answer the question: which is the cause for each specific possibility
Thanks for your comments.
(Dr Don's other videos are also of interest)
Nicolaas Vroom
> |
Please try this video: https://www.youtube.com/watch?v=hk1cOffTgdk It is from Fermilab: |
This video discusses " the doodles called Feynman diagrams".
> | This document discusses specifically the scattering of two photons. These scatterings can be very complicated because many photons can be involved. So my guess above is not that strange. |
The way in which Dr Don Lincoln explains the Feynman diagrams goes into 3 steps. First, he describes the physical behaviour of an experiment For example the collision of two electrons (they bounce off) Secondly, the Feynman diagram which is applicable for this experiment Third the equation that describes the same. (All of this seems rather straight forward starting from the physical behaviour)
Next, he remarks how difficult it is to solve such an equation. I don't know what he means with solving such an equation but my guess is if you start with an equation it is impossible to predict the physical behaviour. The reason is that there can be a certain amount of information loss between step 1 and step 2. The problem is that the path followed by each electron towards the point of collision is not symmetric. One electron can be in front compared with the other, being behind. That means the electron in front will issue a photon and the electron behind, will receive the photon. That means the path of the photon is not vertical (instantaneous) but with a slope (inclined?) indicating a duration
What this document so specific makes it that even such a simple experiment (the collision, bouncing off, of two electrons) studied at more detail, can be physical so complex. In some sense, I'm not amazed. If you draw the path of an electron in 3D as a horizontal line, a point on this line as the point of collision and a sphere as the starting point of both electrons towards the point of collision, then you can imagine that there are thousands of physical possibilities how such a collision can evolve, leading to different physical results. (specif as other particles or photons are involved)
My point is that it is not mathematics that is the driving force behind all different types of processes but the physical details of the processes studied.
Nicolaas Vroom
> | On Sunday, 5 January 2020 17:55:33 UTC+1, Nicolaas Vroom wrote: |
>> |
Please try this video: https://www.youtube.com/watch?v=hk1cOffTgdk It is from Fermilab: |
> |
This video discusses " the doodles called Feynman diagrams". |
SKIP
> |
My point is that it is not mathematics that is the driving force
behind all different types of processes but the physical details of
the processes studied.
Nicolaas Vroom |
Actually no. You’ve misrepresented what the challenges actually are.
To get a feel for what Don Lincoln is calling the hard part, you’re going to have to read, not just watch his videos. Those are not the way to learn the challenges.
-- Odd Bodkin — Maker of fine toys, tools, tables
> |
Nicolaas Vroom |
> > |
The way in which Dr Don Lincoln explains the Feynman diagrams goes into 3 steps. First, he describes the physical behaviour of an experiment For example, the collision of two electrons (they bounce off) Secondly, the Feynman diagram which is applicable for this experiment Third the equation that describes the same. (All of this seems rather straight forward starting from the physical behaviour) |
Skip
> |
Actually no. You’ve misrepresented what the challenges actually are.
To get a feel for what Don Lincoln is calling the hard part, you’re going to have to read, not just watch his videos. Those are not the way to learn the challenges. -- Odd Bodkin — Maker of fine toys, tools, tables |
To make your point, you should give more detail.
Nicolaas Vroom
> | On Wednesday, 8 January 2020 20:35:36 UTC+1, Odd Bodkin wrote: |
>> |
Nicolaas Vroom |
>>> |
The way in which Dr Don Lincoln explains the Feynman diagrams goes into 3 steps. First, he describes the physical behaviour of an experiment For example, the collision of two electrons (they bounce off) Secondly, the Feynman diagram which is applicable for this experiment Third the equation that describes the same. (All of this seems rather straight forward starting from the physical behaviour) |
> |
Skip |
>> |
Actually no. You’ve misrepresented what the challenges actually are. To get a feel for what Don Lincoln is calling the hard part, you’re going to have to read, not just watch his videos. Those are not the way to learn the challenges. -- Odd Bodkin — Maker of fine toys, tools, tables |
> |
To make your point, you should give more detail. |
I’m not going to shortcut for the lazy.
What’s your reason for not reading books?
> |
Nicolaas Vroom |
> |
Nicolaas Vroom |
> > | On Wednesday, 8 January 2020 20:35:36 UTC+1, Odd Bodkin wrote: |
> >> |
Nicolaas Vroom |
> >>> |
The way in which Dr Don Lincoln explains the Feynman diagrams goes into 3 steps. First, he describes the physical behaviour of an experiment For example, the collision of two electrons (they bounce off) Secondly, the Feynman diagram which is applicable for this experiment Third the equation that describes the same. (All of this seems rather straight forward starting from the physical behaviour) |
> > |
Skip |
> >> |
Actually no. You’ve misrepresented what the challenges actually are. To get a feel for what Don Lincoln is calling the hard part, you’re going to have to read, not just watch his videos. Those are not the way to learn the challenges. -- Odd Bodkin — Maker of fine toys, tools, tables |
> > |
To make your point, you should give more detail. |
> |
I’m not going to shortcut for the lazy. |
That means that Odd doesn’t know any more detail....he only make assertions.
> | On Wednesday, 8 January 2020 20:35:36 UTC+1, Odd Bodkin wrote: |
> > |
Nicolaas Vroom |
> > > |
The way in which Dr Don Lincoln explains the Feynman diagrams goes into 3 steps. First, he describes the physical behaviour of an experiment For example, the collision of two electrons (they bounce off) Secondly, the Feynman diagram which is applicable for this experiment Third the equation that describes the same. (All of this seems rather straight forward starting from the physical behaviour) |
> |
Skip |
> > |
Actually no. You’ve misrepresented what the challenges actually are. To get a feel for what Don Lincoln is calling the hard part, you’re going to have to read, not just watch his videos. Those are not the way to learn the challenges. -- Odd Bodkin — Maker of fine toys, tools, tables |
> |
To make your point, you should give more detail. Nicolaas Vroom |
Quantum Electrodynamics and Feynman's motivations for and success of Feynman diagrams, or tunneling diagrams, should be for a general notion of always tunneling as through space.
Here this involves a dichotomy of scattering and tunneling of the particles for as where they're waves.
I'm not particularly attached to this notion but it seems a complement of the interpretation. Where it works out that it's not a necessary abstraction, it's yet informative.
Diagrams generally are useful for operations in diagrams as operations on what they (partially) model.
Feynman's most striking contribution seems to be the path integral for sum-of-histories. Where the diagrams are (partial) models of the results, it helps a lot to be able to add them up as for their primary impulse, even if they run out and aren't then necessarily connected to the underlying model.
> >> |
Actually no. You’ve misrepresented what the challenges actually are.
To get a feel for what Don Lincoln is calling the hard part, you’re going to have to read, not just watch his videos. Those are not the way to learn the challenges. -- Odd Bodkin — Maker of fine toys, tools, tables |
> > |
To make your point, you should give more detail. |
> |
I’m not going to shortcut for the lazy. What’s your reason for not reading books? |
I read as many articles and books as possible. What is more important I also try to review them To get an idea please select this link: https://www.nicvroom.be/book_review.htm
Nicolaas Vroom
> |
I read as many articles and books as possible.
What is more important I also try to review them
To get an idea please select this link:
https://www.nicvroom.be/book_review.htm
Nicolaas Vroom |
Also, I notice that you did not list any basic physics books that teach the essentials of mechanics, reference frames, etc. And others are just popularizations like Hawking’s Brief History of Time. Why are you not learning the basics first before diving in over your head?
> | "the doodles called Feynman diagrams". |
That's a JOKE. Feynman diagrams are not really "doodles", they just LOOK like doodles. Feynman diagrams are a graphical method of identifying and summing the many terms in a perturbation expansion of the amplitude for some specific process, described by the Lagrangian of a quantum field theory. Each diagram corresponds to an integral, and the amplitude of the process is computed by summing the values of all the integrals. There are precise rules about what elements appear in the diagrams, and one must come up with ALL possible combinations of those elements that obey the rules -- that is a difficult combinatorial problem, and using diagrams is MUCH easier than the algebraic methods used before they were invented. (The rules are determined by the mathematical structure of the Lagrangian.)
So you can find images that use "+" and "-" signs between diagrams, because each diagram actually represents a complex number (the value of an integral).
For instance, in QED one classifies the diagrams by how many vertices they have, because each vertex corresponds to multiplying the integral by a factor ~ 1/137. With enough additional vertices the contribution to the overall amplitude becomes negligible, because the integrals also usually get smaller when there are more vertices.
That doesn't work in QCD, because the vertex factor is of order 1, and the integrals don't systematically get smaller. So other tricks are used to collect diagrams such that the various members of each collection cancel each other. For instance, one theoretical argument that there are exactly three generations of quarks and leptons is that if there were any other number of generations then certain collections would not cancel, and that would introduce non-renormalizable infinities.
There are more complications and subtleties (e.g. renormalization, Fermi and Bose-Einstein statistics, ...), but that's the gist.
Tom Roberts
> | On 1/8/20 9:22 AM, Nicolaas Vroom wrote: |
>> | "the doodles called Feynman diagrams". |
> |
That's a JOKE. Feynman diagrams are not really "doodles", they just LOOK like doodles. Feynman diagrams are a graphical method of identifying and summing the many terms in a perturbation expansion of the amplitude for some specific process, described by the Lagrangian of a quantum field theory. Each diagram corresponds to an integral, and the amplitude of the process is computed by summing the values of all the integrals. There are precise rules about what elements appear in the diagrams, and one must come up with ALL possible combinations of those elements that obey the rules -- that is a difficult combinatorial problem, and using diagrams is MUCH easier than the algebraic methods used before they were invented. (The rules are determined by the mathematical structure of the Lagrangian.) So you can find images that use "+" and "-" signs between diagrams, because each diagram actually represents a complex number (the value of an integral). |
bring me to your leader.
> |
Just making stuff up and pretending it is true is USELESS.
There have been 1000 - 1800 Ph.D. in physics awarded in the U.S. each year (1972-2017), many more in other countries, and EVERY ONE of them understands SR without "doubting its validity". Some fraction of them understand GR as well, without you fantasized doubts. This COMPLETELY DWARFS the thiny number of vocal crackpots who do indeed doubt the validity of relativity, without understanding it. |
I have doubts in SRT, too.
My main point of critique: SRT (from 1905) contains a HUGE number of errors.
I counted above two-hundred errors of all kinds in 'On the electrodynamics of moving bodies'.
The large number itself deserves an explanation, since it would raise questions like: was there EVER any review process of SRT?
Possible explanation: these errors are no errors, since the text is part of 'education' of - for instance - these 1800 Ph.Ds per year (in the USA alone). And they should learn, but nothing useful (the 'real deal' comes later).
Similar observation stem from other scientific texts.
Some are quite good, but some authors seem to assume, the reader does not understand anyhow and actually should not.
TH
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