Author Topic: Scharnhorst effect + EM field greater than the Schwinger limit =c value increase  (Read 8230 times)

Offline Giovanni

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The research to overcome the speed of light has so far concentrated on bending space time in the appropriate ways: http://publicationslist.org/spacetimeshortcut

But this is not the only way: there is also the 'Scharnhorst effect'. Scharnhorst believed that the virtual pairs slowed down light and that, in certain circumstances, when, for example in the Casimir effect, in a space region there were less virtual pairs than normal, the value of c grew.

His demonstration uses only the maxwell equations and the quantum mechanics but is not complete in some way (I did not understand the technicalities in that regard) anyway what happens when in an area of ​​space there is an electric field greater than the Schwinger limit?
https://en.wikipedia.org/wiki/Schwinger_limit

Theoretically an electric field so intense separates the virtual pairs ... so, since the light is no longer restrained, the value of c increases?
(The wiki does not talk about the possibility of separating virtual pairs with an electric field greater than the Schwinger limit. You will find everything here: http://www.nytimes.com/1997/09/16/science/scientists-use-light-to-create-particles.html)

Schwinger's limit is not yet reachable experimentally, but in a few decades they expect it to become .... so whoever will live will see it.
What do you think?

I summarize briefly for those who did not have time to read the whole discussion:

The main idea is as follows:
1) Virtual couples slow down the light.
2) One way to prevent this from happening is to use an electric field (perhaps electrostatic) above the Schwinger limit to separate the virtual dipoles in electrons and positrons. Since individual electrons and positron can not absorb a photon, the slowing effect is prevented.

The main objection is the following:
Quote
You seem to have separated "absorbing a photon" and "accelerated by the E field" as intrinsically separate events. In reality, these are different words for the same thing. Classical electrodynamics doesn't have the concept of photons, and QED which brings in the discrete nature is hard to explain because quantum is weird. If you aren't familiar with them, I can post the classical EM equations that can be used to show how energy and momentum would balance for an electron being accelerated by the E-field.[1] These are perfectly valid equations as long as you are operating in the regime of large numbers (avoid quantum and individual photons), which should be good for an electron in a strong, roughly uniform E-field.
« Last Edit: 09/03/2017 10:35 AM by Giovanni »
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline gospacex

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Offline Giovanni

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an interesting and peer reviewed article about the content of this discussion:
Does the speed of light depend upon the vacuum ?
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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an interesting and peer reviewed article about the content of this discussion:
Does the speed of light depend upon the vacuum ?
It doesn't appear to be pear reviewed. arXiv does not do peer reviews, and I do not see a journal that it was published in.

They make some silly statements such as
Quote
In an absolute empty vacuum the induced charges would be null because there would be no charges to be separated and the capacitance of our parallel-plate capacitor would go to zero when we would remove all molecules of the gas.
This fragrantly ignores the changes on the plates themselves, negating one of the primary motivations for their hypothesis.

They have more free parameters in their theory than needed to fudge things to match the results, so their claim of a way to calculate permittivity from other values is simply false. They managed to get within an order of magnitude, but when they need arbitrary fudge factors to get better than order of magnitude, there appears to be no actual value in their theory, since no meaning is provided for the arbitrary constants.
« Last Edit: 05/26/2017 01:13 AM by meberbs »

Offline Giovanni

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« Last Edit: 05/26/2017 07:54 AM by Giovanni »
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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arXiv does not do peer reviews
but EPJ does

The quantum vacuum as the origin of the speed of light
Peer review is imperfect, and the rest of my previous post stands.

Offline Giovanni

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If you have criticisms on Xavier's article send him an email and speak directly with him: you can improve the quality of his article.

There is another article that develops the same idea:

The quantum vacuum at the foundations of classical electrodynamics

However virtual pairs exist: it has been proven experimentally. (See the link in my first post).
If they exist, they affect the vacuum permittivity, the vacuum permeability, and the speed of light in the vacuum.

What happens if you delete them?

It's not my field of experience but reading the article from Scharnhorst I'm convinced that:
1) when the number of virtual pairs tends to zero c diverges.
2) When the value of c changes in a certain space region Loretz transformations change in agreement. So if c grows, relativistic effects weaken and the limit speed achievable with a reasonable amount of energy increases.

If (2) is correct, interstellar journeys are at hand: simply change the c value in the space region surrounding the spaceship with an electric field greater than the Schwinger limit. The traditional propulsion is good: fusion, antimatter, ramjet or even propellantless photon rocket or em drive. The acceleration of 1g is also good.
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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If you have criticisms on Xavier's article send him an email and speak directly with him: you can improve the quality of his article.
Really not worth my time, and the main complaint is the arbitrary constants, and I somehow doubt that would change anything for them, because they are well aware they have arbitrary constants.

This new article like the last one only gets to order of magnitude. You citing these articles in this context seems to indicate that you don't really understand the point of the articles. They are not saying what you seem to think they are. They point out some interesting things, but are more suggesting a direction of thought than forming a complete theory, or one that even approaches the predictive capability of existing theories.

However virtual pairs exist: it has been proven experimentally. (See the link in my first post).
yes.
If they exist, they affect the vacuum permittivity, the vacuum permeability, and the speed of light in the vacuum.
Not necessarily true, by a longshot, and astronomical data makes this extraordinarily improbable. If you think the articles you provided show this, you did not understand what they said.

What happens if you delete them?
The translation of that question is : What happens if you have a magic wand? It should be clear why I can't give a meaningful answer to that question.

It's not my field of experience but reading the article from Scharnhorst I'm convinced that:
...
It is clear this isn't your field, since your conclusions diverge from those of the articles you cite. you may wish to read them again more carefully.

Offline Giovanni

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If you think the articles you provided show this, you did not understand what they said.
from the first article
<<We describe the ground state of the unperturbed vacuum as containing a finite density of charged ephemeral fermions antifermions pairs. Within this framework, ε0 and μ0 originate simply from the electric polarization and from the magnetization of these pairs when the vacuum is stressed by an electrostatic or a magnetostatic field respectively. Our calculated values for ε0 and μ0 are equal to the measured values when the fermion pairs are produced with an average energy of about 30 times their rest mass. The finite speed of a photon is due to its successive transient captures by these virtual particles.  >>

You look very skeptical .... but what I'm most interested in is this:
Quote
astronomical data makes this extraordinarily improbable

Could you expand this point better?



“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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If you think the articles you provided show this, you did not understand what they said.
from the first article
<<We describe the ground state of the unperturbed vacuum as containing a finite density of charged ephemeral fermions antifermions pairs. Within this framework, ε0 and μ0 originate simply from the electric polarization and from the magnetization of these pairs when the vacuum is stressed by an electrostatic or a magnetostatic field respectively. Our calculated values for ε0 and μ0 are equal to the measured values when the fermion pairs are produced with an average energy of about 30 times their rest mass. The finite speed of a photon is due to its successive transient captures by these virtual particles.  >>
The phrase "Within this framework" is very important, it shows they are not claiming evidence of how the universe works, just suggesting an interesting possibility, and give the fudge factors they need, it doesn't come close to being a better model than what we currently have unless someone comes up with a way to greatly improve upon it. Your statement of absolute fact that virtual particles determine the vacuum parameters misses the entire point.

You look very skeptical .... but what I'm most interested in is this:
Quote
astronomical data makes this extraordinarily improbable

Could you expand this point better?
We have observed spectra of stars, and other things that give us information about whether there is any variation of the speed of light, or other fundamental constants across the universe. I'll admit to wondering sometimes whether enough consideration is given to this possibility when analyzing data, but lots of smart people spend way more time than me analyzing it, and it would be foolish to think none of them ever consider such a question. I don't have time to do any thorough research right now to give you links, but I know there is research that constrains variability in the fundamental constants. I know there are some theories out there that try to fix complications with inflation using variable speed of light, but the type of speed of light variations you are discussing are different and should cause more noticeable local effects.

Offline Giovanni

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The article speaks about transit time fluctuations:

<<We note that the fluctuations vary as the square root of the distance L of vacuum crossed by the photons and are a priori independent of the energy of the photons. [....] The strongest direct constraint from astrophysical observations is obtained with the very bright GRB 090510, detected by the Fermi Gamma-ray Space Telescope [8], at MeV and GeV energy scale. [....] Assuming that the observed width is correlated to the emission properties, this sets a limit for transit time fluctuations σT of about 0.3 f s m−1/2 [....] The very fact that the predicted statistical fluctuations should go like the square root of the distance implies the exciting idea that experiments on Earth do compete with astrophysical constraints since we expect fluctuations in the femtosecond range at the kilometer scale. An experimental setup using femtosecond laser pulses sent to a 100 m long multi-pass vacuum cavity equipped with metallic mirrors could be able to detect this phenomenon. With appropriate mirrors with no dispersion on the reflections, a pulse with an initial time width of 9 fs (FWHM) would be broadened after 30 round trips in the cavity, to an output time width of ∼13 fs (FWHM). An accurate autocorrelation measurement could detect this effect.>>

so direct experimental observation is possible....it may seem obvious but it would be very important to do an experimental test considering the implications of the article.
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline Giovanni

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There is another experimental test described in the first version of the article: (but not in the second version)
With an electric (and magnetic) field you can increase the life time of virtual pairs and this affects the speed of light.

Summarizing briefly:
1) With an electric and / or magnetic field, the lifetime of virtual pairs increases and this results in a reduction in the speed of light.
2) However, if the field is higher than Schwinger's limit, virtual dipoles break into electrons and positrons. Since a single electron or positron can not absorb a photon, the photons move in the vacuum without interacting: the value of c increases.

Point 1 is in article "Does the speed of light depend upon the vacuum ?".
Point 2 is my hypothesis: the only thing tried experimentally is that with a field larger than the Schwinger limit electrons and positrons appear in the vacuum.

Another topic related question: what is the density of virtual pairs? Looking in the internet the only estimate I found is in this article: ZPE and Relativity
You also find this book: Natural Philosophy Alliance, vol 9, 2012

The article says: << Even in a very small volume of space, the number of virtual particle pairs is enormous. From the "jiggling" of electrons and their Compton frequency, it can be deduced that one cubic meter contains at least 10 42 virtual particle pairs. >>
Unfortunately, there is no derivation in the article of the reported number.

If you found any mistakes in the information provided and/or non-physical assumption please tell me: I am particularly concerned with errors in point 2. Thank you.
« Last Edit: 06/01/2017 05:14 PM by Giovanni »
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline Giovanni

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Some other speculations:
Reading articles here and there I realized that:
1) Pulling virtual pairs from the vacuum creates negative energy
2) Negative energy repels gravitationally matter
If 1 and 2 are correct then extracting electrons and positrons from the vacuum is possible to obtain a propulsion based on a gravity-like force. This implies that you can separate the two variables:
1) Acceleration perceived by passengers. (Which can be fixed at 1g)
2) The actual acceleration of the ship. (Which can have any value having enough energy to extract enough pairs)

Gravity-like propulsion and FTL travel: they are both needed for a mature interstellar flight technology and both point in the same direction. (Extract positron electron pairs from the vacuum  with an electric field greater than the Schwinger limit)
« Last Edit: 06/03/2017 11:08 AM by Giovanni »
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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so direct experimental observation is possible....it may seem obvious but it would be very important to do an experimental test considering the implications of the article.
If it is as simple of an experiment as they described, I find it odd that unless I somehow misread the paper, they did not actually numerically state the constraints imposed by existing experiment.

Summarizing briefly:
1) With an electric and / or magnetic field, the lifetime of virtual pairs increases and this results in a reduction in the speed of light.
2) However, if the field is higher than Schwinger's limit, virtual dipoles break into electrons and positrons. Since a single electron or positron can not absorb a photon, the photons move in the vacuum without interacting: the value of c increases.

Point 1 is in article "Does the speed of light depend upon the vacuum ?".
Point 2 is my hypothesis: the only thing tried experimentally is that with a field larger than the Schwinger limit electrons and positrons appear in the vacuum.
...
If you found any mistakes in the information provided and/or non-physical assumption please tell me: I am particularly concerned with errors in point 2. Thank you.
The reduction of speed of light part in part 1 is also a hypothesis.

The second point seems like it is related to your next post "1) Pulling virtual pairs from the vacuum creates negative energy" Pulling electron-positron pairs from the vacuum would require energy, but the conclusion that negative energy would appear doesn't actually follow. Because of relativity, being above the Schwinger limit actually requires multiple photons. The multiple photons breaks the"can't be absorbed" rule, as does the fact that the electron and positron would be in close proximity after they separate. Negative energy does have all sorts of interesting applications in general relativity, but we have seen no evidence of it existing. Getting to claiming negative energy is created requires multiple large logical leaps.

Offline Giovanni

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The Casimir effect is tied both to decreasing the number of virtual pairs in a certain space region and to creating negative energy.

Harold Puthoff's article speaks of the Casimir effect as a means of creating negative energy:

EXPERIMENTAL CONCEPT FOR GENERATING NEGATIVE ENERGY IN THE LABORATORY

But the article that explains it better is that of John G. Cramer:

FTL PHOTONS

<< Thus, the more closely the plates are spaced, the broader becomes the spectrum of virtual photons that are suppressed, and the vacuum between the plates becomes "emptier" of vacuum fluctuations and lower in energy density.
Since the energy density of normal vacuum is defined as zero, the vacuum between the metal plates actually becomes a region of negative energy density. >>

so  "emptier" of vacuum fluctuations => lower in energy density => negative energy density region




**** Hypothesis: ****

Another way of seeing the main topic: (Breaking Schwinger limit and negative energy)

Virtual pairs are created for a temporary violation of energy conservation.

With such a large electrical field, it becomes a permanent violation, generating positive mass (ie positive energy).

There must be a more general conservation law requiring that even negative energy be generated to compensate.

Add this:

Quantum vacuum is a black box with associated some known properties including energy.

So this mysterious ' more general ' principle of conservation of energy is: the energy of the vacuum is preserved. (energy of created pairs + energy of vacuum = constant)

Suppose the energy of a certain vacuum region is E0. When it is created a pair with energy Ep (kinetic + mass energy) the energy of the vacuum becames E0-Ep.

When the pair becomes annihilated the vacuum energy returns E0.

Obviously, if the couple is not annihilated (for the strong electric field), the vacuum energy remains  E0-Ep.

As in physics   E0 = 0 E0-Ep is negative.

(i admit: this hypothesis realy need an expert check....someone must do a complete energy balance including E field energy)
« Last Edit: 06/03/2017 08:14 PM by Giovanni »
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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**** Hypothesis: ****

Another way of seeing the main topic: (Breaking Schwinger limit and negative energy)

Virtual pairs are created for a temporary violation of energy conservation.

With such a large electrical field, it becomes a permanent violation, generating positive mass (ie positive energy).

There must be a more general conservation law requiring that even negative energy be generated to compensate.
...
There is already a general energy conservation law (until you get to curved space-time, then things get messy)

You seem to be ignoring the fact that the E-field can and will transfer energy to the particles. There is no energy violation that needs negative energy to account for it, because electromagnetic fields are transferring energy to the system, and you are just drawing the box of what you are considering too small to see that whatever generates the electric field would lose energy.

Casimir effect is a different beast all together, and I am not up to trying to explain that one right now.

Offline Giovanni

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Quote
There is no energy violation that needs negative energy to account for it, because electromagnetic fields are transferring energy to the system
Perhaps there are so efficient ways of converting energy into an electric field (superconductors?) that the energy demands to power a field higher than the schwinger limit is less than the energy of the pairs created.
Are there any theoretical considerations that can exclude with certainty that possibility?

and returning to the topic "Scharnhorst effect + EM field greater than the Schwinger limit =c value increase"

can you explain better:

Quote
Because of relativity, being above the Schwinger limit actually requires multiple photons.


and

Quote
The multiple photons breaks the"can't be absorbed" rule, as does the fact that the electron and positron would be in close proximity after they separate.

Even if the two particles are in close proximity you can make the probability of the interaction with the photons as small as you want simply increasing the field.

more intense the field => less time the two particles are close enough to absorb the photon
« Last Edit: 06/04/2017 08:09 AM by Giovanni »
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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Quote
There is no energy violation that needs negative energy to account for it, because electromagnetic fields are transferring energy to the system
Perhaps there are so efficient ways of converting energy into an electric field (superconductors?) that the energy demands to power a field higher than the schwinger limit is less than the energy of the pairs created.
Are there any theoretical considerations that can exclude with certainty that possibility?
Yes, conservation of energy (and momentum) is built directly into Maxwell's equations. This applies to any time force is applied to a charged particle. The energy will always be perfectly balanced, although in a real system with resistances and such, some more energy than goes into the particle will be converted to heat as well.

and returning to the topic "Scharnhorst effect + EM field greater than the Schwinger limit =c value increase"

can you explain better:

Quote
Because of relativity, being above the Schwinger limit actually requires multiple photons.

the wikipedia article on the Schwinger limit explains this fairly simply, but basically, since all reference frames are equivalent, you can always convert to a reference frame where the single photon has less energy, which also reduces the field strength. With 2 photons travelling in different directions, there is now a minimum energy reference frame (center of momentum frame)


Quote
The multiple photons breaks the"can't be absorbed" rule, as does the fact that the electron and positron would be in close proximity after they separate.

Even if the two particles are in close proximity you can make the probability of the interaction with the photons as small as you want simply increasing the field.

more intense the field => less time the two particles are close enough to absorb the photon
I don't see how the probability of interaction could ever change from 100%. No matter how strong the external field, the field of the particles will still be able make them interact with each other, allowing an energy and momentum balance to be created. That is without the fact that once you add in quantum (which you have to do at this scale) wave-particle duality means that these particles probably start out literally overlapping.

Offline Giovanni

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I don't see how the probability of interaction could ever change from 100%. No matter how strong the external field, the field of the particles will still be able make them interact with each other, allowing an energy and momentum balance to be created. That is without the fact that once you add in quantum (which you have to do at this scale) wave-particle duality means that these particles probably start out literally overlapping.

I am not convinced. Thanks anyway for writing time. A brief summary of my topic:
We define a time interval τ such as the interval between the birth of the virtual couple tstart and the moment when it loses its ability to capture a photon tend. This instant tend is defined as the time when one of the following two things happens:
1) annihilation: positron and electron come into contact.
2) separation: the distance between the positron and the electron exceeds (due to a field above the Schwinger limit) the value L0 for which they are a dipole capable of absorbing a photon. (Such a value L0 must exist otherwise every positron electron pair in the universe is a dipole capable of absorbing a photon)
This τ will be a function of the field in which the pair is located. A growing function for E values ​​below Schwinger's limit (in this case increasing E retards annihilation) and decreasing for E values ​​above Schwinger's limit (in this case increasing E anticipates separation).
The probability that a photon interacts with a dipole in the time interval dt will be a function of the virtual pairs density ρ, τ, c0 (the speed of light in the 'true vacuum') and dt. Note that fixed ρ, c0 and dt p (τ) has the properties p(0) = 0 and p is continuous so p(τ) = 1 for each τ > 0 is to be excluded. In addition τ -> 0 => p(τ)->0.

I think I'll contact some other physicist, maybe the authors of 'Does the speed of light depend upon the vacuum ?' and I'll hear what they think.
Thanks again and excuse the many questions: I hope I have not stressed too much.
« Last Edit: 06/04/2017 06:04 PM by Giovanni »
“The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of the infinity, and it was not meant that we should voyage far.” ― H.P. Lovecraft
Job 12:22 "He reveals the deep things of darkness and brings utter darkness into the light."

Offline meberbs

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A couple other things to consider, separation simply won't happen unless energy is absorbed to allow it, making part of your reasoning circular.

Also, I should have mentioned before that while an electron in free space cannot fully absorb a photon, it would typically scatter a photon, absorbing some energy from it, and effectively replacing the photon with a lower energy one travelling at a different angle. See Compton Scattering for the math. (Compton scattering is typically in the context of an atom, but high enough energy photons are assumed so that the electron is treated as a free particle, and the math is done as if it was a single photon-electron collision in free space.)

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