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a reply to: DanielKoenig

I'm not going to read the wall of text but if you really want to understand a photon correctly you have to learn enough physics.

Here is the closest physical represntation, it will assume you know enough about classical physics for it to make sense.

Consider a microwave cavity with conducting edges. Then, a classical physicist may use the Maxwell equations for electromagnetism in a vacuum which are partial differential equations---this is physics, assertion about the real world.

Then 'expand' the electromagnetic field into a summation of time dependent coefficients and spatial operators as an alternative representation of the potentials/fields---that is mathematics of partial differential equations and not physics. These are known as "modes".

In classical physics the allowable values of the amplitudes of these modes can be any non-negative real number---a continuum. In quantum physics, this is not true---there is some minimum 'jump' (whose energy depends on the mode) and you go from zero to a finite (but small) value. Why? Because the world works this way---this is a physical assertion of nature and not something mathematically determinable.

Think of a volume control on a stereo, some are smoothly varying, but others change their attenuation value in small, discrete steps.

What is a photon? the electromagnetic fields and energy which is in the difference between a state of EM field X and Y where Y is the same as X except one mode has been boosted up in energy and thus field the minimum quantum.

To be more technically correct you need to understand the notion of eigenstates and that it's even more complicated because the state of nature is a wavefunction of functions and in QM you can represent reality in different "bases" and in some of them there are states with definite 'quantum number' and there are physical interactions which increase and decrease these numbers by exactly plus and minus one---the thing which is the difference is the photon.

The field of quantum optics defines all of these rigorously and completely with quantitative accuracy, but you'll need a semester of graduate quantum mechanics first before it will be understandable.

And in fact, all the rest of matter, electrons etc, work the same way---electrons are persistent excitations of the lepton field just as photons are excitations of the electromagnetic field. But because of distinct differences in the physical laws, in particular conservation laws, electrons really stick around and don't flit in and out of existence---there is a strong conservation law on their number rarely violated---but that is distinctly not the case with photons. So they look really different empirically though in the very bottom (quantum field theory) they are cousins.

originally posted by: DanielKoenig
a reply to: delbertlarson


Because if I take the statement, as being the crown, and whole, of the defining capstone of EM Radiation production and existence: The only thing we know about the generation of EM radiation is that it coincides with electron acceleration (pardon me, is it charged particle acceleration in general?

Yes.

An accelerated proton produces EM radiation? If a single quark could be accelerated would it produce EM radiation?

Yes.

You see the essence of my crux is: Where does EM radiation come from? Where and how is it produced? Does the same quantity and quality of EM radiation always exist?)

The mathematical description in the Standard Model gives all known avenues which connect other types of particles and fields to electromagnetism, the specific form and strength of the couplings determine the effects.

Then this leads me to ask something like: If you could theoretically hold a single electron between your fingers, and you existed in a vacuum in between the milky way and the nearest galaxy: And you accelerated the electron up and down up and down 1000000 times: Would you be creating EM radiation?

Yes. That's how an antenna works. By applying time varying voltage, electrons preferentially pile up on one end, and are deficient on the other end (creating a net positive charge). Oscillate the voltage and the electrons push around.

The case that you are discussing, a bare electron in vacuum comes about mostly in plasmas, and the acceleration up and down comes from incoming electromagnetic waves, which move the electron, which then re-raditates, causing changes in the observed electromagnetic fields. This is computable by the laws of physics and has experimental consequences.

When stars were first made, did they happen to be made in ores of EM radiation: and the stars like pinata's (making the distinction between baryonic matter, and EM RAdiation: When I say the star, or star, I do not mean EM radiation: I refer to only the atoms which make up the star, nucleus, electrons (we can ignore gluons for now, I hope): so imagine all these atoms, like a cage, like a net, like lattices of lattices: did this giant thick 3/4d cage of atoms, happen to big bally coelesce surrounding a huge field of ""EM Radiation"" "stuff" "substance":

That sounds like a ball of jibberish to me.

The electrons of the atoms in the stars movements would be like your finger holding the electron moving it up and down up and down, would be like taking your finger and leaning over your filled bathtub and dipping it in and out and in and out and in and out: would be like being fully submerged in the ocean and taking your hand and moving it up and down and up and down: all of these forcing the propagation of the surrounding "Stuff Medium" away from the point of your mass fingers acceleration.

Yes, in fact the thermodynamics of warm material substances, because they are made of charged particles as part of atoms, their thermal motion produces electromagnetic radiation with a particular strength and spectrum known as 'black body radiation'. A 'substance' made out of neutral neutrinos wouldn't do this.

It is either: Something like that is the case: or not.

And the or not, would entail, that Em radiation would then be: not part of some all encompassing medium: but more similar to how atoms, an electron, nucleus, exists separate from everything else, as its own singular entity:

A local area of EM radiation in either potential, would be "separate" in that it is "different than its immediate surroundings",

Yes, because EM propagates just fine in vacuum in the absence of matter. It is in the Standard Model its own distinct separate field.

How do we as scientists and physicists approach determination, of whether Em Radiation exists like separate baseballs exist (or self propagating waving snakes: who are also made of particles!!): Or like the all encompassing ocean medium exists?

More like the ocean, except ocean goes through fish as well. Ocean is EM field and fish are persistent excitations of the fish field, very 'fishy' in certain places and in discrete clumps, and very not-fishy in other places, that's more like a matter field.

All Fundamental Fields of Nature appear to exist simultaneously and independently over all space in the Universe and superimposed everywhere on one another.

Hi all, sorry if I'm going off the current topic, but wanted to know if there was any traction within the physics community for the theory of retro-causality. I've heard it argued (Jack Sarfatti mainly) that this would explain the currently "missing" dark matter as well as the apparent paradox inherent in the double slit experiment.

Curious if this is theory is growing in popularity or considered total quackery.

a reply to: Harpua
I'm no expert on the topic but I'll offer a few thoughts. There have been some hypotheses involving retrocausality from reputable physicists, but I don't think any retrocausality has ever been sufficiently proven to convince most people, in fact as far as I know causality is still a principle of physics where we can draw light cones in space-time diagrams to show the limits of causality. Since the light cones are based on the speed of light, one implication of faster-than-light travel might be some sort of retrocausality.

NASA has a research lab working on advanced propulsion technologies, one of which is a warp drive (faster than light) and I wouldn't describe that research as quackery, but on the other hand I don't rate our chances of successfully developing a faster than light drive as very high. We know what we know and we don't know what we don't know and some of this research involves things we don't know, like the FTL drive might require a particular type of exotic matter...but does such matter exist? We don't know. The research team leader Dr White likes to point out that the properties of dark energy validated by observation are similar to the properties of the exotic matter we would need for a warp drive which suggests it might not be impossible.

Dr. White is quite candid that the warp drive research is speculative and it may never work but he seems much more optimistic about the possibility than I am.

There are various other theories that involve retrocausality, some of which have run into problems like the Wheeler–Feynman time-symmetric theory.

Some people try to interpret the delayed choice quantum eraser experiment as evidence of retrocausality, but it's really not. So is there any evidence of retrocausality?

In 2011 Daryl Bem published a paper claiming evidence of retrocausality. I don't work in his field but from what I can tell he wasn't viewed as a quack but as an accomplished professional in his field, so I was interested to read his paper and I even participated in one of the replication experiments using his methods. The article criticizing his methodology was complimentary about the detail which accompanied his paper, something sometimes lacking in that field.

If you read Bem's paper, he explains that his field is littered with claims such as these which failed to replicate and had serious flaws in methodology, and that indeed his own work could be subject to such if the results could not be replicated. Some replications were apparently successful but the methodology has been criticized by LeBel and Peters:

Fearing the Future of Empirical Psychology: Bem’s (2011) Evidence of Psi as a Case Study of Deficiencies in Modal Research Practice

In this methodological commentary, we use Bem’s (2011) recent article reporting experimental evidence
for psi as a case study for discussing important deficiencies in modal research practice in empirical
psychology. We focus on (a) overemphasis on conceptual rather than close replication, (b) insufficient
attention to verifying the soundness of measurement and experimental procedures, and (c) flawed
implementation of null hypothesis significance testing. We argue that these deficiencies contribute to
weak method-relevant beliefs that, in conjunction with overly strong theory-relevant beliefs, lead to a
systemic and pernicious bias in the interpretation of data that favors a researcher’s theory. Ultimately, this
interpretation bias increases the risk of drawing incorrect conclusions about human psychology. Our
analysis points to concrete recommendations for improving research practice in empirical psychology.
We recommend (a) a stronger emphasis on close replication, (b) routinely verifying the integrity of
measurement instruments and experimental procedures, and (c) using stronger, more diagnostic forms of
null hypothesis testing.

I'm not familiar with Sarfatti's theory or how it could explain dark matter, but I consider this somewhat of a black mark on his record: "My personal professional judgment as a PhD physicist is that Geller demonstrated genuine psycho-energetic ability at Birkbeck, which is beyond the doubt of any reasonable man, under relatively well controlled and repeatable experimental conditions."

He somewhat redeemed himself by later retracting that after seeing James Randi perform the same illusion, however that wasn't enough for him to regain his reputation as a skeptical professional in my mind.

originally posted by: DanielKoenig
a reply to: joelr

define energy: "Again it's all just energy... and some of the vast energy inside each atom is released...Much of the energy is released as photons. "

How is the energy released in photons?:

Each Atom.

In what form does 'vast energy' exist in Atom?

In what way, in what form, does 'vast energy', as it exists in the answer to question above, 'release', 'become' photons?

Atoms have mass which is equivalent to energy.

When the atoms ate vibrated too much they can no longer remain stable and hold their energy content. Because of the law of conservation of energy the energy has to go somewhere and much of it goes into the EM quantum field.
This allows for the creation of photons.

originally posted by: DanielKoenig
"The fields for all of the particles are already everywhere in space-time. " psychotic video game child statement

You would need to be more specific as to how quantum field theory is related to psychosis, video games and children...?

Then maybe back up and start with if you have a problem with classical field theories (our most successful theories of nature besides quantum theories) also?

QFT can resolve issues with particle creation and annihilation and with relativity that even relativistic quantum theories have trouble with. So maybe you can give some ideas as to why quantum fields solve so many issues but are really false theories? Instead of stringing 4 random words together as a reply?

If the moon was obliterated by an asteroid or by some other means, will the oceans go through any kind of violent events or changes?

a reply to: Arbitrageur

Thank you... there have been some articles recently that made it sound like a possibility and it got me excited.

a reply to: mbkennel

The field of quantum optics defines all of these rigorously and completely with quantitative accuracy.

Except for when it is off by roughly 100 orders of magnitude.

All kidding aside, thanks for your excellent layman's overview of QFT. As I think you may know, I have been pursuing a different approach.

originally posted by: wickd_waze
If the moon was obliterated by an asteroid or by some other means, will the oceans go through any kind of violent events or changes?

If the moon disappeared it would be bad because a lot of water would drop and probably cause large waves. If it was hit just hard enough to break it apart then it could just clump back together and the mass would still be there to produce tidal forces.
But if it was hit really hard and all the pieces were scattered into space and into different Earth orbits (some terminal) then there would be a big effect on the oceans.

I've been thinking about the big bang and I've got a poorly researched and reasoned idea that the very idea of "something from nothing" requires dimensions we cannot experience. My reasoning comes down to 2 points.

A sphere going through a 2D universe would start at a singular point seemingly from nothing and then disappear back into nothingness.

Also, if time was created at the big bang there needs to be another way to differentiate when changes happen otherwise whatever caused the big bang could not happen in the first place.

Which leads me to my question...

Is it provable or disprovable that the physics we live by are a subset created by a higher level of physics?

a reply to: Krahzeef_Ukhar
Superstring theory posits 10 dimensions, M-Theory posits 11 dimensions, and bosonic string theory posits 26 dimensions but the extra dimensions are small so you wouldn't see a spherical object like a bowling ball passing through our three dimensions "start at a singular point seemingly from nothing and then disappear back into nothingness".

String theory has a level of popularity but it also has critics who say string theorists have been hypothesizing for decades but still don't have any experimental evidence to confirm "string theory" which should probably be called string hypothesis instead since it lacks the support of our other theories. See my signature for context.

One problem in testing what the media has called the "big bang" conditions tested at the LHC is that is somewhat misleading since the LHC energies don't reach the energies of the earlier part of the big bang which we believe goes beyond the physics we now understand. So how much more energy would a collider need to test for the extra dimensions? That depends on how large the higher dimensions are:

Will the LHC be able to test String Theory?

The strings can become excited to higher modes, which is a prediction specific to string theory and in principle observable. The energy necessary to make these excitations depends on the radius of string theory’s extra dimensions: The smaller the radius the larger the energy necessary to excite the strings. The most natural scenario puts the radius of the extra dimensions at the string scale: on the order of 10^19 GeV, give-or-take. In this case, testing string theory is hopelessly out of reach of the LHC, which reaches ~10^4 GeV at maximum, even with the recent upgrade.

In the case that string theory’s additional dimensions are quite large and in the range testable by the LHC, they would make themselves distinctly noticeable. The production of tiny black holes is one of the predictions. This process becomes possible because the extra dimensions make gravity on short distances much stronger than General Relativity with only three space dimensions predicts. For the same reason also the production of gravitons, the quanta of gravity, would become possible at the LHC if the extra dimensions were large. These phenomena give rise to specific observables that have been computed in great detail.

Additional dimensions by themselves would not tell us that string theory is correct, because this is only one ingredient of the full theory. However, if we were able to find evidence for extra dimensions it would speak very strongly for string theory and one also would expect true string phenomenology, that might reveal itself for example in string balls or fuzz balls, to be not too far away. Extra dimensions are the best-case scenario to test string theory at the LHC.

Physicists thoroughly scanned the previous LHC runs for signatures of black holes or graviton production that would speak for extra dimensions. They found exactly nothing. The possibility still exists that the somewhat higher energy of the upcoming run will deliver the sought-after evidence, which is a convoluted way of saying I don’t believe it but some of my colleagues refuse to give up hope.

Like the author of that article, I don't believe the LHC will have enough energy, and of course the gap between an energy of 10^4 GeV at the LHC and the hypothesized string theory energies of 10^19 GeV is enormous. How large would the collider need to be and where would it get the energy to test that? Regardless of the specific answer it's far beyond the capabilities of the LHC and even the proposed larger collider in China.

originally posted by: delbertlarson
a reply to: mbkennel

The field of quantum optics defines all of these rigorously and completely with quantitative accuracy.

Except for when it is off by roughly 100 orders of magnitude.

There is no fundamental theory of the cosmological constant that is well accepted, and seeing the 100 orders of magnitude in being 'off', that's a signal that you're going down a really wrong path (aka, "Hello?! McFly?") , especially if you consider the 'zero point' energy to not actually be at the physically relevant zero.

a reply to: joelr

Hey, was I on or off target on my description of quantum fields? It's not really my specialty at all---I'm pretty sure you know more.

a reply to: Arbitrageur

Cheers.
Are you saying that it's a possibility but it's beyond our ability to test?

a reply to: Krahzeef_Ukhar
I thought what I posted was pretty clear, but to sum up what it says is:

1. If the extra dimensions in string theory (or related superstring or m-theories) were large enough, they might be detectable by the LHC.
2. No evidence of #1 has yet been observed so if the extra dimensions exist they must be smaller than what the LHC is capable of detecting.
3. The expected size of the extra dimensions is so much smaller than what the LHC can detect that yes, it's a possibility but it's beyond our ability to test at the present.

The reason for the clarification is that we do have the ability to test for larger extra dimensions to the extent explained in my prior post, and have tested for them, and found nothing, but if they are as small as some string theorists think, they are very far beyond our ability to test now or at any time in the foreseeable future. However the testing might not be beyond the capability of a Type II civilization on the Kardashev scale, but we are a long way from that.

a reply to: mbkennel

The Cosmological Constant problem is not the only problem with quantum field theory. Renormalization and running couplings are also things that were of great concern to the founders of QED. In the forward by Schwinger on his book on QED he laments the situation quite clearly. And then there is this from Feynman:

The shell game that we play ... is technically called 'renormalization'. But no matter how clever the word, it is still what I would call a dippy process! Having to resort to such hocus-pocus has prevented us from proving that the theory of quantum electrodynamics is mathematically self-consistent. It's surprising that the theory still hasn't been proved self-consistent one way or the other by now; I suspect that renormalization is not mathematically legitimate.

In more recent years the modern-day sophists earn comfortable livings promoting QFT and the qualms expressed by the founders are frequently set aside. But there are some of us who still find the situation troubling.

One of the early motivations for QED was the difficulty of having the Laplacian operator within the radical if we straight-forwardly just use the exact high-velocity energy equation and then make the obvious substitutions. However, at least for stationary states, this problem can be overcome by rearranging the equation and squaring both sides which results in an equation that can be treated numerically. This should, in principle, allow for a non-perturbative quantum solution for many interesting physical problems. I posted a thread about this in July 2016 (see here). You responded with some solid points back then. Since then I've published the paper in the reviewed journal Physics Essays. The reviewer raised some of the same objections raised by members here, which led to an improvement of the work as I put in several sufficient explanations in the way of comments that the reviewer found persuasive. I hope to put the whole thing (including comments) online at InfoGalactic in the next few months, as the editor of Physics Essays has kindly allowed me to do so once six months have passed after publication. I will of course let everyone here know when it is available, or if the desire is more imminent anyone can purchase the work here.

The bottom line for the present discussion is: 1) QFT predicts zero point energies that are not observed and QFT also involves "shell games" and "hocus-pocus" (quoting Feynman) that should really not be a part of physics; 2) if we set QFT aside we need another way to treat high-velocity quantum mechanical problems where Schrodinger no longer applies; 3) I have proposed a new approach that is similar to Schrodinger, but is correct at high-velocity; 4) the new approach does not require a quantization of the vacuum, but rather, allows for individual quantum entities to exist on their own and not as a part of a field; which 5) does away with the need for the field and hence does way with the universal zero point energies of the vacuum, does away with the need for renormalization, and allows for a return of a more classical understanding of our world.

A second motivation for QFT rather than my approach is that my approach is not relativistic. However, that objection is easily set aside if we simply return to Lorentz or to a modification of Lorentz that I published many years ago.

a reply to: Krahzeef_Ukhar

They have been testing quantum mechanics assumptions for decades. I remember back in 1962 they let some civilian llamas design a nuclear bomb to use in civil defense projects. Produced 100 times more radioactive fallout then it needed to, and the fallout cloud polluted a huge area northeast of Iowa. This is what actually happened.


www.youtube.com...

Borrowed from Intrptr..

So i have a question.

Sith can shoot lightning bolts out of their hands. This would imply that via the force they can summon and control EM. If so shouldnt they also be able to conjure along with electrons photons and positrons. So realistically sith should be able to shoot lasers and positron beams out their hands too right?

a reply to: BASSPLYR
I like science fiction but a lot of science fiction has some really bad science in it, or the science is completely lacking. One exception is Star Trek which hired scientific consultants to review the scripts. Being fictional of course they didn't actually have to explain how the Heisenberg Compensator worked, but at least they knew it was necessary for the transporter to work.

The science in Star Wars is embarrassing at times. One famous scene people like to make fun of is Hans Solo saying the Millenium Falcon made the Kessel Run "in less than 12 Parsecs" implying it was fast. The problem is that a Parsec is a unit of space, not of time. Then George Lucas made some screwball comment about how that was supposed to make scientific sense, so some boffin decided to investigate to see if that was possible and he seems to conclude here that the attempt by Lucas fails just as miserably as the more common interpretation, maybe even worse:



So my advice: Don't even try to make sense out of nonsense like that. But if the show had a scientific consultant like Star Trek, I think those guys are still alive so you could e-mail them and ask them what they were thinking. One thing I heard them say is that sometimes they would point out a problem with the science and the creative staff would keep it in the script anyway since it was a necessary plot device for which they didn't have a solid scientific substitute, so it's not perfect as they will tell you, but overall I think it's got better science than a lot of other science fiction shows because of the expertise they hired.

What would be the theoretical computer (processing power) required to render a 1920x1080 HD resolution screen at 1.855e+43 frames per second?

I'm very curious as to what some of the responses might be on this even if there isn't any possible answers.

Thanks.