What is the Nature of Photons?

[kote]

The Bohm interpretations you speak of are non-local as well as non-relativistic... but since locality and relativity ever pervade modern models of our current theories... I am then able to conclude that Bell's belief was that the universe is non-deterministic.

Except that Bell didn't accept locality as necessary. From http://plato.stanford.edu/entries/bell-theorem/:

Although the main result of Bell [1964] is his theorem demonstrating the the impossibility of recovering the statistical predictions of quantum mechanics with a local realistic theory, Section 3 of this paper concludes with the construction of a nonlocal model — violating Remote Context Independence but not Remote Outcome Independence-- which does recover the statistical predictions of a particular entangled quantum state.​

There's also still the fact that Bell published the statement that "indeterminism [is] not forced on us by experimental facts."

Locality is certainly an important concept. But Bell did not deny determinism - he supported it.

 

[Tipi]

You would then still be describing the properties of matter, since matter would be made of the oscillations of 1-dimensional strings. And you have thus, still failed to describe the apple as "being" without describing "how it behaves."

I don't agree. Saying an apple is made of strings (beables) is a statement stronger than saying it behave like it is made of strings (observables). The difference manifest itself when you consider entangled states of QM. Beables (hidden variables) are then non-local concepts, while observable are completely local. If you want to avoid non-locality, you have to avoid statement about what things are, that is, beables. This is why I don't agree with you, since it seems you say that beables are ultimately the same things as observables.

I thought I was clear on that subtlety in a previous post... maybe it is just hard for us to communicate.

My point here was that the "cute" question seems to ask for a beable as an answer because it ask what the thing is. I then tried to argue that it is a question impossible to answer with my actual understanding of QM since then it will lead to non-local properties of things. I then suggest to answer the question in terms of the observables attached with the thing, discussing what it do instead of what it is.

If you don't agree with all that, it doesn't matter. It is just that we see things differently. Some people, as Bohm and maybe you, think only the observable have to be relativistically invariant. So, it doesn't matter to him his theory has non-local beables, since these beables lead to completely relativistic observation. That means that in bohmian mechanics, the violation of relativity is, by definition, unobservable!


TP

 

[Evolver]

Except that Bell didn't accept locality as necessary. From http://plato.stanford.edu/entries/bell-theorem/:

Although the main result of Bell [1964] is his theorem demonstrating the the impossibility of recovering the statistical predictions of quantum mechanics with a local realistic theory, Section 3 of this paper concludes with the construction of a nonlocal model — violating Remote Context Independence but not Remote Outcome Independence-- which does recover the statistical predictions of a particular entangled quantum state.​

There's also still the fact that Bell published the statement that "indeterminism [is] not forced on us by experimental facts."

Locality is certainly an important concept. But Bell did not deny determinism - he supported it.

I know, that's precisely what I'm saying. Bell argued for non-locality, but he did not offer an alternative theory as complete and thorough as say relativity or QED, which are the modern paradigms of our description of the universe. This being said, that implies that Bell's determinism only comes about via non-locality, and our models are based on relativity and locality. So since Bell disagrees with the locality of these models, his theorem then states that our understanding of the universe currently is non-deterministic. The current models result in only probabilities, and these are obviously not an accurate representation of information.

And that's precisely why I said I don't agree with this before, because I don't think you can mix Bell's theorem with our current models... a new model is required. That's all I was saying when I said Bell thought of the universe as non-deterministic.

I don't agree. Saying an apple is made of strings (beables) is a statement stronger than saying it behave like it is made of strings (observables). The difference manifest itself when you consider entangled states of QM. Beables (hidden variables) are then non-local concepts, while observable are completely local. If you want to avoid non-locality, you have to avoid statement about what things are, that is, beables. This is why I don't agree with you, since it seems you say that beables are ultimately the same things as observables.

I thought I was clear on that subtlety in a previous post... maybe it is just hard for us to communicate.

My point here was that the "cute" question seems to ask for a beable as an answer because it ask what the thing is. I then tried to argue that it is a question impossible to answer with my actual understanding of QM since then it will lead to non-local properties of things. I then suggest to answer the question in terms of the observables attached with the thing, discussing what it do instead of what it is.

If you don't agree with all that, it doesn't matter. It is just that we see things differently. Some people, as Bohm and maybe you, think only the observable have to be relativistically invariant. So, it doesn't matter to him his theory has non-local beables, since these beables lead to completely relativistic observation. That means that in bohmian mechanics, the violation of relativity is, by definition, unobservable!TP

You're right, I don't agree because you are attempting to avoid non-locality. I'm not saying non-locality is right, but I'm not saying it's wrong either. There are many great physicists that support non-locality, Bell and Bohm among them... but the real problem comes with science's limited grasp of QM. Richard Feynman said he didn't understand Quantum Electrodynamics and he invented the theory. Einstein, Bohr, Bohm, Bell, Von Neumann and many others all sought to discuss locality and non-locality and among them they came up with incredibly different opinions. The problem is we are arguing two sides of an undefined coin. Neither of us can prove anything and therefore this thread is nothing more than individual philosophy.

 

[Tipi]

You're right, I don't agree because you are attempting to avoid non-locality. I'm not saying non-locality is right, but I'm not saying it's wrong either. There are many great physicists that support non-locality, Bell and Bohm among them... but the real problem comes with science's limited grasp of QM. Richard Feynman said he didn't understand Quantum Electrodynamics and he invented the theory. Einstein, Bohr, Bohm, Bell, Von Neumann and many others all sought to discuss locality and non-locality and among them they came up with incredibly different opinions. The problem is we are arguing two sides of an undefined coin. Neither of us can prove anything and therefore this thread is nothing more than individual philosophy.

I deeply respect your point of view. I studied it two years and put my conclusions in a master thesis : I saw no "real" contradiction between realistic quantum mechanics and relativity. However, at the end, I was strongly convinced that the actual formalism of quantum theory has to be interpreted in a non-realistic way, i.e. that it is constructed in such a way that it can make statement only about results of measurements. I think the "realist" point of view is not suitable for the actual formalism, but it could be for something else to come.

So, I think teachers should adopt a strong instrumentalist point of view (no statement about what things are) to avoid contradicting what is said in other courses (e.g. all nature is invariant under the Poincaré group...), and that the realist point of view should be kept for researchers, or very initiated peoples.

Cheers,

TP

 

[Evolver]

I deeply respect your point of view. I studied it two years and put my conclusions in a master thesis : I saw no "real" contradiction between realistic quantum mechanics and relativity. However, at the end, I was strongly convinced that the actual formalism of quantum theory has to be interpreted in a non-realistic way, i.e. that it is constructed in such a way that it can make statement only about results of measurements. I think the "realist" point of view is not suitable for the actual formalism, but it could be for something else to come.

So, I think teachers should adopt a strong instrumentalist point of view (no statement about what things are) to avoid contradicting what is said in other courses (e.g. all nature is invariant under the Poincaré group...), and that the realist point of view should be kept for researchers, or very initiated peoples.

Cheers,

TP

This I do agree with. ;)

 

[Entropee]

I don't think you will be satisfied with the answer. "Pure form of energy" is more of a science fiction concept than a scientific one. Science can say "a photon is the thing that behaves in this way (and then list its properties)", but it sounds like you will find that answer unsatisfactory.

Note that no matter what you are talking about, you can eventually get to this point. What is water? What is air? "Yes, but what is it really" is a question that ultimately has only the answer, "the thing with these properties".

I was going to reply to this thread but you took the words out of my mouth haha.
Lots of scientists are too afraid to admit "we don't really know" what a photon is, we know ALL about them, but have no idea what they are because we can't quite comprehend them, kind of like 1D.

 

[RUTA]

I'll beg to differ with science answering the question "why?". Yes, it's a small semantic point but a very important one. Science asks "how" not why. Why implies some unknown motivations. The sky is blue rather than red because blue was God's favorite color. How the sky appears blue is a different question, having to do with the scattering of light and HOW that occurs.

So for now there is light and how it behaves. Beyond that it's open season. Think of it like the old problem of the motion of the planets when the Earth is regarded as the center of the universe. You can develop complex mathematical systems that actually predict what is going on to a degree, but they are not the model you are looking for because the complexity keeps you from understanding. But a simple shift of point of view can suddenly produce the model that provides great insight into HOW it all works (not why!)

"The ideal of scientific explanation is a matter of logical deduction, given a unified set of deep explanatory principles that are themselves accepted, for the time being, without explanation. But of course the ideal of scientific explanation is one for ongoing improvement. Perhaps from the fundamental laws of microphysics, by some consistency criterion, it will turn out that the constants of nature are tightly constrained or even uniquely determined. But even then we would still have the task of explaining the laws themselves at a still more fundamental level. At some stage scientific explanations always turn into descriptions—‘that’s how it is folks’—there is no ultimate terminus in science for the awkward child who persists in asking why! I do not believe the aim of some self-vindicating a priori foundation for science is a credible one." Redhead, M. (1990). “Explanation” in Explanation and Its Limits, edited by Dudley Knowles, Cambridge University Press, Cambridge, pp. 135-154.

 

[kote]

"I do not believe the aim of some self-vindicating a priori foundation for science is a credible one." Redhead, M. (1990). “Explanation” in Explanation and Its Limits, edited by Dudley Knowles, Cambridge University Press, Cambridge, pp. 135-154.

Wait, what? If he is happy with science being arbitrary, answering no fundamental questions, and not serving any purpose... then how on Earth would he ever be in a position to write about science? I agree with everything said up until the last sentence. Whether he does science out of curiosity, for a paycheck, to be a good citizen, because he doesn't know what else to do... no matter what the reason, that reason is his self-vindicating a priori foundation without which he would have literally no reason to do any science at all.

The idea that we can do anything without some conscious or unconscious motivation is just unintelligible, as is the idea that we can seek scientific knowledge without some concept of what knowledge is and why we should have it.

 

[alxm]

Wait, what? If he is happy with science being arbitrary, answering no fundamental questions, and not serving any purpose...

That's not what he said at all. What he said is essentially "there will always be a 'why?'".

 

[ViewsofMars]

Replying to the question, "What exactually is a Photon?"

From NASA’s COSMICOPIA Glossary:
Proton
"The positively charged part of an atom. The number of protons determines which element the particle is. It is part of the nucleus."
http://helios.gsfc.nasa.gov/gloss_op.html

More about "Proton Composition" can be learned from the link below.
http://helios.gsfc.nasa.gov/compos.html#proton

I highly recommend NASA's COSMICOPIA Glossary. I like it. And I love NASA!

 

[RUTA]

That's not what he said at all. What he said is essentially "there will always be a 'why?'".

Exactly. I'm not sure I agree with Redhead on this point, but I do agree with a previous post that as of now, science provides "how" not "why." I think it's possible to avoid the dilemma posed by Redhead if, for example, we admit a priori that the entire enterprise is one of self-consistency. Then the ultimate expression would not be something "at the bottom," begging for justification from something yet "deeper," but a mathematical/formal articulation of the self-consistency criterion for the process as a whole.

 

[ViewsofMars]

Just wishing to add some depth to this conversation pertaining to the how, why, what, etc. Questions are often asked and scientists reply. (Review the "Ask a Scientist" archives.
http://www.Newton.dep.anl.gov/archive.htm).
A good example of such:

From Ask A Scientist from Astronomy Archive.

Why stars?
Author: chelsea
Why are there stars?

Response #: 1 of 1
Author: samuel p bowen
Good question. Matter attracts itself to other matter. So stuff collects
in blobs. If the blobs contain nuclei that can be transformed into more
stable nuclei and give off energy, then a star is formed. The star "burns"
the little nuclei of hydrogen and makes helium. The energy that is left
over makes starlight.
http://www.Newton.dep.anl.gov/Newton/askasci/1995/astron/AST153.HTM

 

[kote]

That's not what he said at all. What he said is essentially "there will always be a 'why?'".

Explain the sentence I actually objected to then. I agree with the part about how there will always be a why in science, and I said as much.

"I do not believe the aim of some self-vindicating a priori foundation for science is a credible one."​

Self-vindicating a priori is redundant. He might as well have said, "I do not believe the aim of a foundation for science is a credible one." Without a foundation there literally is no point.

 

[alxm]

Self-vindicating a priori is redundant. He might as well have said, "I do not believe the aim of a foundation for science is a credible one." Without a foundation there literally is no point.

First: No, it's not at all redundant. You're ignoring important words here and turning what was written into something else. What I believe he meant by "self-vindicating, a priori" is that, you cannot assume that the final 'axiom' of total reductionism (if such a thing is achievable) is actually 'self-evident'. Science cannot justify itself that way, and it cannot assume it will reach that conclusion. So what? Neither can math.

Second: There is no foundation, and that doesn't mean there isn't a point. Epistemology is no more a matter of 'fact' than any other metaphysics. There's no reason to believe that we can know anything to begin with. You can't refute the statement "You can't really know anything for sure". You can point to the fact that it's logically inconsistent (how could you be sure of that statement?), but on the other hand, there's no reason to assume things have to be logical. The fact that the universe does follow logic and self-consistency is itself an empirical observation.

That doesn't mean there isn't a point to Science. It means that piddling about with metaphysics is unproductive. Science cannot prove itself any more than Math can. (And famously, math has essentially proved it can't prove itself)

 

[RUTA]

Explain the sentence I actually objected to then. I agree with the part about how there will always be a why in science, and I said as much.

"I do not believe the aim of some self-vindicating a priori foundation for science is a credible one."​

Self-vindicating a priori is redundant. He might as well have said, "I do not believe the aim of a foundation for science is a credible one." Without a foundation there literally is no point.

Essentially, he's referring to the idea that scientists will find a bottom that justifies itself and, therefore, requires no "deeper" justification, i.e., there would be no more "why." For example, all theories of physics have a foundation, i.e., set of axioms/postulates at bottom. In special relativity, one of the postulates is "everyone measures the same speed of light, regardless of their relative motions." Now, despite the great successes realized by following the consequences of that assumption, many physicists still ask, "why is it that everyone measures the same speed of light?" It's an empirical fact and it "works," so why don't all physicists accept this postulate as "self-vindicating?" He's saying that he doesn't believe physicists will ever have a foundation that they accept as "self-vindicating," so that no matter what the foundation is at any given time, we will still want to know "why that particular foundation?"

 

[kote]

That doesn't mean there isn't a point to Science. It means that piddling about with metaphysics is unproductive. Science cannot prove itself any more than Math can. (And famously, math has essentially proved it can't prove itself)

The statement "science is productive" is a foundational a priori statement. The statement "there is a point to science" is an a priori statement that gives science a foundation. One cannot deny an a priori foundation of science without denying the statement "there is a point to science." Science doesn't give itself a point. It can't give itself a foundation. Its foundation must be a priori.

Self-vindicating and a priori are redundant in that a priori principles can be reduced to statements in which no deeper explanation is possible.

I agree with RUTA about what was probably actually meant.

 

[enotstrebor]

I beg to differ: science can answer quite a lot of 'why's. For example, it can answer why the sky is blue, why water is transparent, etc. In your case, the question of why the photon forms, and how it actually forms is well known (has been known for decades). The answer, unfortunately, must be given in terms of more advanced concepts which you may/may not have an intuitive understanding of, and the answers provided in the previous posts may have appeared mystifiying, as a result. But, I assure you, the 'why' the 'what' and 'how' of a photon is well known.

What is the behavior of the photon, for example as it effects matter is well understood and these behaviors are well modeled by the mathematics.

However, one can't even say if maxwell's equations or any other photon mathematical model, is the behavior of the photon or the behavior of the reaction to the photon.

One might note that the four dimensional E,B matrix has the same sign form as the four dimensional gyroscopic matrix. So these `fields' may actually be the two gyroscopic reaction modes of the particle to a single force (of course this requires another real spin like behavior from what is viewed as non-real spin object).

Once your recognize that all present models are interaction models without separate uniquely defined sources as opposed to uniquely defined situational behaviors (photon-photon, photon-matter, matter-matter) then you understand that the present models can not tell you what (what is the photon, what is the electron) and thus can not tell you how and thus can not say why.

 

[lightarrow]

Replying to the question, "What exactually is a Photon?"

Proton
"The positively charged ...

It was to test the readers' attention?

 

[ViewsofMars]

March 23, 2008 - NASA

Aurora From Space
What do auroras look like from space? From the ground, auroras dance high above clouds, frequently causing spectacular displays. The International Space Station (ISS) orbits just at the same height as many auroras, though. Therefore, sometimes it flies over them, but also sometimes it flies right through. The auroral electron and proton streams are too thin to be a danger to the ISS, just as clouds pose little danger to airplanes. ISS Science Officer Don Pettit captured a green aurora, pictured above in a digitally sharpened image. From orbit, Dr. Pettit reports, changing auroras can appear to crawl around like giant green amoebas. Far below, on planet Earth, the Manicouagan Impact Crater can be seen in northern Canada. Credit: Don Pettit, ISS Expedition 6, NASA
http://www.nasa.gov/multimedia/imagegallery/image_feature_44.html

The image is awesome. Be sure to click open that link. I like that mint tulip green.

Don't forget to read my messages 40 and 42 if you haven't already.

 

[Entropee]

that picture is amazing :O

 

[ViewsofMars]

Yeah, it's incrediable, and what a time to be alive. Check this out from The International Space Station. Click the music video on the upper right of their screen. I feel like I'm there with them ~ ~~ ~ Loving it..."We are the experiment"
http://www.nasa.gov/externalflash/ISSRG/index.htm

 

[Entropee]

yeah that was tight, i want to experience zero gravity someday..

 

[RUTA]

yeah that was tight, i want to experience zero gravity someday..

You could jump on a trampoline, you'd be experiencing zero g as soon as you left the surface on each jump. For a longer time at zero g you could do a bungee jump. There are some amusement park rides that give you a brief free fall experience.