swansont

The ratio of the frequency from E=hf and your calculation should be an integer.

Maxwell doesn’t tell you how many photons you have. But there have to be an integral number, so you can check to see it’s at least consistent.

What’s the problem? A 1 keV electron being stopped can give you a photon of maximum 1 keV. Its frequency would be given by hf

If you converted all the energy, then KE = hbar*omega. It would represent the maximum frequency in case there were losses. But you have to have a situation where you only get one photon.

A B field won’t stop an electron, and would not represent a constant acceleration. Also, a photon in a cavity is a different problem from Bremsstrahlung.

And if we had a different definition for the second, the value would be different. The value of c is arbitrary.

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Everyone would see it as full if that could happen, and it wouldn't be intermittent. As Ghideon has said, earthshine is too weak of an effect.

Only when they are moving? Nope. Maxwell's equations work for static charges. The divergence of E is still proportional to the enclosed charge. The current only shows up in Ampere's law. Using your example: Maxwell's equations describe both static and dynamic systems. It's not junk science. It's physics. An extension of your thought process is that a bar magnet does not exhibit magnetism since there are no moving charges, which is clearly nonsense.

An atomic transition is described by the wave function of the atom, not the wave function of a photon, and isn't presented as an EM field. Not sure how you conclude that. You don't know what the wave function was before the measurement, and I don't know what "released intact" means. It's dubious to say an AFM image is the measurement of the wave function. It's a measurement of electron position.

The meter is not "based on 10s". The SI prefixes are, but you can talk about kilomiles, millifortnights and megapounds if you want to. Our standard measures are arbitrary.

I think a lot of older folks have a hard time with the concept. One underlying issue is that we're taught some basic stuff in school, but the actual science is more complicated and subtle. We see it here all the time, in less socially-charged situations, when people insist on something based solely on e.g. classical/Newtonian physics, and ignore the fact that relativity and QM exist. They don't appreciate the fact that they are ignorant, and have no concept of the depth of their ignorance. Even though I have some difficulty in appreciating some of the subtlety surrounding sex and gender, I have heard smart people explain it, so at least I recognize that "X chromosome, Y chromosome" is not the end-all, be-all of the discussion, and that this is real: it's a spectrum, rather than being binary. But that's partially because I know this "you only learn the tip of the iceberg in high school" to be true about physics, so it's not hard to recognize it must also be true in biology. However, I have no idea if that is the source of Ms. Rowling's position, since other effects can come into play, such as religious teachings crowding out and/or ossifying capability for processing new and better information.

Why all the mummies, then?

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It’s based in how we study and teach physics. You might think otherwise, but non-mainstream science should be discussed in speculations. Open a thread there and explain how the physics of static charges doesn’t fall under “electricity” in the study of “Electricity and Magnetism”

I'm trying to point out that it doesn't matter. The second in defined in terms of a Cesium-133 atom experiencing no external effects (no fields, at 0K) and yet we are still able to realize the second, because we make corrections, so we know what the frequency would be under the idealized conditions. Gravity can be corrected for as well. (We do it relative to the geoid already. It's just a matter of changing the reference for the correction) The gist of the OP would be similar to claiming that rulers are no good because the material they are made from has a temperature coefficient, and no ruler is going to be at the exact temperature where the length was precisely defined. And the answer would be the same: we can correct for that if we need to, and in any event the effect is small.

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——— Another way of quantifying the effects would be gravitational redshift of light. "As an example, take the white dwarf star Sirius B, with a gravitational field ~100,000 times as strong as the Earth’s." — the redshift is 3 x 10^-4 http://astronomy.swin.edu.au/cosmos/G/Gravitational+Redshift Depends on what you mean by high, but yes. The kinematic effect depends on v, the gravitational effect depends on the change on gravitational potential. If you put a clock in the center of a hollow planet, it would run slow, even though gravity would be zero in there. Because it would take energy to remove the clock and get it to an infinite distance away (i.e. the reference we use for gravitational PE)

I'm not sure how this matters. The clock shift depends on the potential. Zero force does not equate to zero potential.

We have equations that allow us to calculate the effect. Clocks are affected by more than gravity, and we do the same thing in realizing the length of the second — e.g. you measure the temperature and the magnetic field present, and remove the shifts from the frequency (blackbody and Zeeman, respectively). You can do the same thing for gravity. You could calculate that e.g. your clocks are running slow by a part in 10^10 relative to a point far away from a source of gravity and make that correction. Again, you would only do this if it mattered, and the shift is going to be small. Small is compared to the size of the effect you are measuring. If you are measuring the orbit of extrasolar some planet, and it's about one earth year, then the number I used would mean you are off by around a part in 10^17, which is almost certainly small relative to the precision of the measurement Again, these effects are quantifiable, and any discussion of this should include that. No, it's equal to the gravitational potential, and then divided by c^2. Near earth, the effect is around a part in 10^16 per meter of elevation. (GM/rc^2) The black hole at the center of the galaxy has a big mass, yes, but r is also very large. If we were much closer to the galactic center, this would start to become a large effect. Clocks are affected by our non-circular orbit about the sun, as they sample different gravitational potentials. You can leverage this to confirm aspects of general relativity. But you need good clocks to try, because the effect is small. Except it's not zero gravity that's important. It's zero gravitational potential that would be the reference. But as I said before,w e can measure the effect, since we can measure gravity and distance, so we can correct for it, if we need to.

The OP was basically a link to the NYT article, a quote and a very short summary of one aspect of it, so no.

The energy of a harmonic oscillator is (n+1/2) hbar*omega — energy is there even in the n=0 state. It's consistent with the HUP, of course, as it must, but the zero point energy drops directly out of the solution. It's not something that was added on because of the HUP (which is how "introduced" makes it sound, to me)

Yes, but we can measure the local effect, and, if need be, correct for it. In any event, it's small.

ag400002 has been banned for repeated, persistent thread hijacking