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posted on Jul, 8 2018 @ 10:24 AM
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originally posted by: delbertlarson
Feynman perhaps didn't like philosophy because neither he nor anyone else of his time had a satisfactory solution for what is going on. He was in good company, as the best minds for decades wrangled with the issue. The whole Copenhagen philosophy was a dodge. However, just because this problem has simmered for so long doesn't mean it isn't important.
I don't think you understand what Feynman says about philosophy and you didn't understand his example of gravity in the video I posted in your other thread, this one:



He described three different philosophical approaches to describing gravity which sound completely different, but they end up making the same predictions. Then you made some comment about something completely different from gravity which showed you didn't even seem to understand he was talking about gravity. He does care about different philosophies because he thinks one approach might give a theoretical physicist insights that he might not get from a different approach, even if they end up being equivalent. But his advice for the theoretical physicist as far as I can tell is to not get married to one philosophy, rather consider all of them, which by the way is exactly what I try to do with the subject of the interpretation of quantum mechanics discussed in the OP.

Feynman elaborates a little more on how he thinks is a good idea to keep all the different philosophical approaches in mind in this video:



He asks if approach "A" and approach "B" result in the same consequences (observations or experimental results), how are we going to decide which one is right? "No way, not by science". So far that's more or less the case with the quantum mechanics interpretations which predict the same consequences, which is why we can't use science to pick one, at least not until someone devises an experiment to distinguish between them which I think some researchers are trying to do. This is the point I was getting at in my prior reply; if they are experimentally equivalent, why would I try to pick one when it's scientifically impossible to do that (pending further experiment if that may show a difference).

1:45
"psychologically we must keep all the theories in our head, and every theoretical physicist that's any good, knows 6 or 7 different theoretical representations for exactly the same physics, and knows that they are all equivalent, and that nobody is ever going to be able to decide which one is right at that level, but he keeps them in his head hoping that they'll give him different ideas for guessing".

So Feynman does care very much about the approaches for that reason, but that's not saying he picks one when it's impossible to do that scientifically, he tries to consider them all for their different insights.

Speaking of theoretical physicists, I thought of you when I watched the question and answer session at the end of this video from the Perimeter Institute, where some theoretical physicists work.



1:35:15
Q: "Do you have any advice to offer to students considering a career in theoretical physics".

1:36:30
A: "When you go into it... you're taking on the most difficult, challenging, impossible problems. You're trying to challenge Einstein, I mean, good luck, hahaha"...."The people in this institute are playing with statistic agent math, fancy computers, you name it...every day. You're with other people who are as crazy as you, and want to challenge Einstein, and want to discover the next big thing." He makes it sound like there's a whole building full of physicists trying to challenge Einstein; i wonder if any will succeed. The main problem I have with Einstein's model is the description of an infinite density singularity in a black hole; there just has to be a better description than that using quantum mechanics, but nobody has figured that out yet and even if they do figure it out theoretically, how are we ever going to confirm the solution with observations? Even if someday we could send a probe into a black hole, I don't know how we will ever send the observations out. Maybe someone can figure out some clever trick using Hawking radiation or something.




posted on Jul, 8 2018 @ 06:21 PM
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a reply to: KrzYma

As I recall, i gave you a lengthy description of how one such detector worked... you brushed it off and said something along the lines of "You don't know how it works, its all just EM waves" without actually being coherent in your reasoning why.

Single photon counting is a well established and understood process. You have previously claimed light propagates from a source and previously have stated that light sources propagate in a spherical wave front. We pointed out soon after that lasers don't behave at all like you described. You never got back to me on that one either.

Let me give you an example. In my current work, we are characterizing the performance of single photon counting devices at deep uv wavelengths, around 170-190 nm now, this is the wavelength. We use a broad band flashlamp that produces light from around 160 to 1000nm (Xenon flash lamp) Due to the atomic structure of Xenon, the emission spectrum has lots of peaks in it, and a long underlying continuum caused by the rather large amount of energy levels and electrons the Xenon atom has.

So, we are only interested in the 180nm region so we use narrow band filters. These filters are made from tuned layers of different refractive index materials, typically in a 1/4 - 3/4 layer structure, where one layer is 1/4 wavelength thick, and the next ontop is 3/4 nm thick, and so on, and so on. So wavelength does appear to be a real thing. It is both a reflection of energy, but also takes some geometrical form too.

The flash lamp produces many many photons, the optical power is around 5 Watts at maximum pulse frequency (whole spectrum) We filter this using optical components as described above and we focus the light onto a device. By applying 4 filters, collimation, focusing and mirrors we can reduce this signal down to single photon level.

The device we are testing is a pixilated geiger mode APD, and contains a shallow junction. Why? well because photon absorption by silicon is very high in the UV, meaning that technically UV gets very readily absorbed, and you will only see a signal from the device if the photon penetrates deep enough to generate charge carriers (electrons - Holes) near to the junction such that they trigger an avalanche process in the device.

The device has some interesting features. The sensitivity of the device is directly related to the wavelength of the light imparted on it. And the signal intensity is related to the amount of photons. The way you describe things, your explanation for these effects is simply that the only property here is that of waveform intensity, and that its all about electrons not being 'at the right place?' You realize how illogical that is? How many electrons do you think there are? I can tell you that, it is quite a lot.

By your own reasoning you seem to suggest that, if it is a geometry affect 'being in the right place' depending on the waveform, we could test this by using a polarized laser, this allows us to control the polarization of the waveform and the wavelength very precisely. And let me tell you that... single photon counting in a device as discussed above, behaves in a Poissonian manner, meaning the signal being generated is due to a discrete quantized source. This behaviour does not change using a polarized laser source.

So if you take planck equation and do a similar calculation as you have seen in above posts, you can, given a light source wattage, calculate the number of photons for a given wavelength. You can apply neutral density filters to reduce the amount of light at all wavelengths by equal amounts. SO if you take a source that is producing of light at a single wavelength and apply lets say neutral density filters that give you a factor of 10000x reduction in signal, resulting in what theoretically should be 10 photons emerging (on average) from the filter, you measure this using a device with independently calibrated and it says, "I see a signal equivalent to 10 photons" the wavelength of your source is 500nm.

Now, you switch the source for a different one... this time it is at 200nm, you apply the same 10000x reduction and your detector has calibrated efficiency meaning its efficiency is equal at 200nm as 500nm. So what is your signal? By your own logic you state that single photons are not a thing, so you expect your signal to look the same regardless of wavelength. What you actually see is your detector telling you that you see 4 photons. Why?

Well because E = hc/lambda, at 500nm the photon has a theoretical energy of 2.47eV, so your 10 photon signal is 24.7 eV worth of energy. Now the other light source, at 200nm each photon is about 6.2eV but the source power is the same right? well the number of photons is actually not the same, despite the power being the same.

The above experiment isn't fantasy, iv done it, you can do it too, (though you'd need equipment that is expensive and not really worth buying to just do that experiment) and i can confirm the above behavour... and not what you seem to suggest which is that 1) single photon counting isnt a thing and 2) wavelength/wattage relations are also not a thing.



posted on Jul, 9 2018 @ 12:48 AM
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Lol looks like a case of GIGO. But be my guest and believe as you please.
While you are at it chk out some videos of astronauts on the moon and gauge the speed of their speech.



posted on Jul, 9 2018 @ 07:00 AM
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a reply to: Arbitrageur

I watched the Feynman three-ways-to-do-gravity video again. I looked for it in my absolute and real thread but did not see it there - perhaps I scanned too quickly or perhaps it was in some other thread. While I didn't find my response, I do recall that it had to do with the magnetic dipole interaction, which has a different force fall off than 1/r*2. That response came about because at 10:01 of the video, Feynman states something about how nature is so exquisitely balanced, and I thought he was going beyond gravity at that point in the discussion to refer to something more general. I thought so because at 10:10 he refers to the "laws of nature" (plural) not the "gravitational law" or "law" (singular). Also, at 10:44 he refers to modifying the laws, again in the plural. Coulomb is also 1/r*2, and I believe that much of his arguments about gravity also pertain to Coulomb, so I thought he was making a general statement about all physical laws at the end. (F = dp/dt is the same for gravity and Coulomb too, as well as for all laws.) But some forces (like the magnetic dipole) are not 1/r*2, so I thought that was relevant to the discussion.

I may still be missing your point concerning the Feynman gravity video. I thought your point was that we could look at physics from different points of view, and that until experiment can decide between those points of view, we must admit that different views are possible. If your point is/was something else, please let me know.

The main issue for me philosophically is realism. I believe that once we give that up we've given up any grounding whatsoever. We can throw down whatever math we want to model experimental results, but I think we lose a lot when we do so. If we aren't attempting to describe a real, objective, reality, then what are we trying to describe?

Thanks for your further clip from Feynman, as it shows that he did value different philosophical approaches. It also in a way supports my view, since the Mayan astronomer was just using math, but the person with the realist interpretation behind the math had an important contribution. But of course, we can't question Feynman now, we can just reply to each other, and I was replying to this:



Until I see some problem with the approach that time is what atomic clocks measure, the definition seems to work as far as i can tell. I have yet to see any experimental results that show a problem with that approach, and I'm not much interested in philosophical nuances personally, though I know some people have an interest in that. As Feynman said, more experience should cure people of the disease of getting too hung up on specific philosophical approaches, and I think he had a point


The main point is this:

Both the quantum collapse problem and the cosmological constant problem can be addressed if we set relativity aside and return to absolute theory. Those are the experimental results that show a problem with treating time as what atomic clocks measure. Quantum collapse can be easily understood as an instantaneous collapse once absolute simultaneity is recovered by proposing absolute time (moving atomic clocks run slow), and using Absolute Quantum Mechanics instead of QFT goes a long way toward solving the cosmological constant problem.

edit on 9-7-2018 by delbertlarson because: improvement



posted on Jul, 9 2018 @ 04:59 PM
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a reply to: Arbitrageur

What I was trying to get across to kryzma is that if you use analogies from water flow and hydraulics to explain electricity for example there will always be a point where the analogy breaks down and won't give accurate results.

I think that could be the issue he is having.

On another note, thank you for writing the explanations that you did. You answered questions i had always had about radio and radio signals. I'm still processing what you said and reading links, but I'll come back a ask questions at some point I'm sure.




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