Recent content by Matterwave

  1. Matterwave

    Random Thoughts part 6

    I'll just quote wikipedia: "Any period of ten years is a decade, and there is no 'official' legal nor administrative start or end point,[1][2] so it can be any arbitrary span of ten years. " "The frequently used method to refer to decades is the cardinal method, which groups years based on...
  2. Matterwave

    Random Thoughts part 6

    Eh, the delineation of a "decade" is somewhat arbitrary anyways. Since most people refer to the decade as 10-19 inclusive (the 2010's) then I think I'm good :D
  3. Matterwave

    Random Thoughts part 6

    "next decade" - FTFY
  4. Matterwave

    A Three Body Problem - Statistical (almost) Solution

    "Solved" is maybe too strong a word for that paper... DNN's are trained to approximate the functions produced by numerical integrators. This leads to a constant-computational cost approximate solution. As far as I can tell anyways...
  5. Matterwave

    What is the role of schools and universities?

    A lot of negativity on the internet suggesting this is not the case...(but I have no idea about the statistics - just remarking on what I see around on the internets these days)
  6. Matterwave

    I Moving frames

    My impression, and I could certainly be totally wrong on this, is that the OP was asking for a mathematical derivation that says that Maxwell is consistent with relativity (i.e. starting from Maxwell's equations, derive that they give a constant speed ##c## for EM waves in all inertial reference...
  7. Matterwave

    I Moving frames

    Although I agree with your conclusion, I don't think this answers OP's question. Unless I'm misreading, this statement simply assumes Maxwell's equations agree with experimental fact, which they do, but the OP is asking why they do.
  8. Matterwave

    I Bohr on measurement

    Sometimes, if you are referring to very old texts (e.g. Bohr) you might notice a big difference between the language and frameworks used there and that used in modern physics. A lot has changed in the last 100 years. There's not just concepts which were proven wrong (e.g. the Bohr atom), but...
  9. Matterwave

    B Basic questions about astronomy

    1. This is easily google-able, see here: https://earthsky.org/space/does-our-sun-reside-in-a-spiral-arm-of-the-milky-way-galaxy 2. In between the galaxies is mostly just empty space. The inter-galactic medium exists (a very diffuse gas), there are dwarf galaxies, and there could be a few stars...
  10. Matterwave

    I Gradients of the Energy tensor

    There's no general answer to this question...##\partial_\beta T_{\mu\nu}## depends on the stress energy tensor and the coordinates you chose...it's like asking "what's ##d\vec{v}/dt##?" without specifying anything about ##\vec{v}##. It's hard to figure out what you're trying to get at. At most...
  11. Matterwave

    B Gravitational Redshift and its effects on Photon

    Can you explain where the quote "Light doesn't lose energy as it ascends. It was emitted with less energy at a lower elevation." comes from? Is that your own hypothesis, or did you read it in a book or lecture somewhere? On the face of it, that statement appears to be simply false - but I might...
  12. Matterwave

    I Proper time?

    I think in a more advanced treatment of SR/GR, that would not be a helpful way to think about proper time, but in elementary treatments (like Serway), this treatment is pretty common. I think it mostly stems from the Newtonian bias of treating coordinate time as a legitimate measure of time...
  13. Matterwave

    I Proper time?

    I think you are confusing the statement that a "geodesic between two events measures maximum proper time" with OP's statement about "shortest measurement of time for two given events". There are many ways one could travel from event A to event B - if one travels along a geodesic then the proper...
  14. Matterwave

    I Proper time?

    Don't get into the "John will see David's clock...and David will see John's clock..." kind of arguments - they will just serve to confuse the issue. The two events in this scenario are "David leaves Earth" and "David arrives on the Moon". For John, the two events happen at two different places...
  15. Matterwave

    Publishing as a citizen scientist

    The minimum of the function is obviously at (0,0)...not sure that's a great goal... :P I don't know if I agree with the (0,0) origin though...It seems a lot of people who have 0 experience in a field nevertheless think they are experts.
Top