Jump to content

swansont

Moderators
  • Joined

  • Last visited

Everything posted by swansont

  1. Oobermensch has been banned for being oober-insufferable
  2. This assumes there are light sources, and that the scientists are so clueless as to not realize this. You don't even give them the benefit of doubt that they'd realize this and turn light sources off, even though I already told you that one would do this. (Plus the fact that if you're doing this with an optical fiber, it's really hard for extraneous light to get in) And possibly enclose the experiment, if needed. I've had setups that did this, so the room lights could be on. Light doesn't get into the box. So I will ask again, what light? I'm telling you there isn't any.
  3. ! Moderator Note Off-topic. This isn’t the place to whine about how you’ve been wronged.
  4. You really should use a search engine for such basic inquiries https://www.ligo.caltech.edu/page/what-are-gw https://en.m.wikipedia.org/wiki/Gravitational_wave
  5. You haven’t explained where these trillions of photons have been conjured from.
  6. swansont replied to Photon Guy's topic in Physics
    Fourth power of the temperature (Stefan-Boltzmann law), but the net power depends on what the reservoir is radiating back at the object. You can’t spontaneously transfer heat to a body at a higher temperature (there has to be work done), per the second law If you have an object at room temperature, it will not transfer heat to the room (regardless of the actual temperature of the room) because there must be a difference in temperature to transfer heat. True for radiation, conduction and convection.
  7. Our physics descriptions are valid back to about 10^-43 sec. Not to zero.
  8. swansont replied to Photon Guy's topic in Physics
    Depends on the temperature difference. Which is why it becomes less efficient with each stage of trying to recover energy.
  9. I used to teach the folks running the reactor. If you actually knew more your son would be in violation of national security laws for having divulged classified material to you, and he’d lose his clearance, and probably his job and pension. You don’t need to separate them; most are irrelevant. They would be thermal photons that don’t trigger the photodetectors. If these are near-visible or visible wavelength photons being entangled and you’re worried about contamination, there are wavelength filters and also the very technologically sophisticated step of turning the room lights off during the experiment. There’s also the coincidence measurement I mentioned, which is a filter in the time domain.
  10. Why do you need to separate the photon? How does this relate to the scenario under discussion?
  11. Yes, that was the revelation of Einstein’s relativity, back in 1905. We perceive length visually, geometrically. Time, not so much. There’s no physics that describes time standing still and contracting length to zero. The equations fail under that scenario. Before the big bang is another thing that physics can’t describe.
  12. Again, your idea of what’s going on isn’t how the experiment is run. It’s done under controlled conditions so there’s virtually no other candidate photons, and you do coincidence measurement to screen out extraneous signals. If you do e.g. spontaneous parametric down-conversion, the entangled pairs are emitted in a particular direction. The bottom line is the folks doing these experiments understand what’s going on, as opposed to some hecklers in the peanut gallery. Declaring that “this can’t work” and the insinuation that you know more than the scientist who have performed the experiments isn’t a good look in light of the fact that this does work.
  13. Length changes, too, under those circumstances
  14. Or perhaps you just don’t know how any of this works. It doesn’t fit with your mental model of what’s going on, but it’s your model that’s wrong, not the experiment. (iow this is argument from incredulity, which is a fallacy; things aren’t wrong simply because you don’t undertand) The light passes through the cube. Straight through for one polarization, at 90 degrees for the other. Which path it takes tells you the polarization. All you have to do is put a photodetector at each path to tell you where the photon went.
  15. So does USNO, via GPS. Time from USNO and NIST typically agree to better than 100ns (often much better); there’s a memorandum of understanding that dictates how well. How is this different from other base unit standards, like length, which is defined in terms of how far light travels in a second? They’re all conventions.
  16. Directional charge? Charge is a scalar. ! Moderator Note Piling nonsense on top of nonsense, and repeating assertions instead of addressing issues. A hand-wave is not a model. We’re done here. Don’t bring this up again.
  17. ! Moderator Note The next step needs to be addressing the many problems that have been pointed out, rather than building on top of a flawed foundation
  18. But without the BH, there is no appreciable gravity. Certainly not enough to do what you claim. And: a dipole? What would the electric dipole moment be?
  19. Depends on the experiment, but you know where the photons are coming from and the wavelengths, so it’s not difficult to do. It’s a cube, 1/2” or 1” on a side. Exactly. And that’s why you need statistics of several photons, as you pointed out.
  20. You’d probably send the light through an optical fiber, which can be coiled up, and the measurement takes much less than a second. Because you entangled the photons. As you’ve been told, if it’s just a random photon there’s no way to tell if it’s entangled Again, as you’ve been told, you need multiple photons to do this. You really need to read the replies in the thread.
  21. Because that’s trivially known, if you’re familiar with atomic physics. Your tone suggests that you think it hasn’t been done. I’ve done it. One way is to send it through a polarizing beam-splitter cube. If the polarization is in one direction it goes straight through. If it’s orthogonal it gets reflected. Knowing which way it goes tells you the polarization I have no idea of the context of this question, but spacetime means you’re talking about relativity, and entanglement is a quantum effect. So you need to explain the connection.
  22. The issue that’s all to common is that interested amateurs watch a video but it’s not saying what they think it’s saying. Saying that the whole lecture is fascination isn’t the issue here - what is in the video that pertains to this particular discussion. It’s unlikely that all 50 minutes are.
  23. It’s unreasonable for you to expect anyone to watch a 50 min video and sort through the arguments, which is why we have a rule against it to add to this: measuring one photon doesn’t even tell you it’s entangled It could possibly rule out entanglement, since the correlation could come out wrong. But that’s it
  24. You can ask questions of the original poster as long as it’s on-topic

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.