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swansont

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Everything posted by swansont

  1. As long as you can avoid collisions, which is difficult. The mean free path of air molecules at room temperature is of order 100 nm. And escape velocity is << c
  2. Light bending around a massive object is predicted by the theory, as is the frequency shift of light as it climbs up or drops down a gravitational well. It doesn't have to "consider" EM, since the effects are, in a sense, orthogonal. i.e. the nature of the interaction doesn't matter. For E=mc^2, the mass of a system decreases when its energy is reduced, regardless of whether the interaction is electromagnetic or nuclear. Much like how F=ma doesn't have to specify what kind of force is involved.
  3. I think the problem here is the definition of "exist" which was not provided. The explanation of the Casimir effect that invokes virtual particles uses Feynman diagrams In both of these cases, the answer is clearer if the question were "do virtual particles have a measurable effect" because in both cases, they obviously do, and for physics, that's enough.
  4. SFN defines it a particular way. Then let’s see the model and the support.
  5. Any non-mainstream proposal is speculation here. And someone with your claimed background should know what science means by “a theory”
  6. “Circumstances” that have an impact that we can model and test. As with other “circumstances” that occur in other parts of physics (e.g. symmetries that give rise to conservation laws, circumstances of a lack of acceleration of a frame that gives rise to Newton’s laws, etc.) Relativity doesn’t care. We’ve tested it on macro “circumstances” and it keeps passing the tests.
  7. No. And scientists are not engineers. The plural of anecdote is anecdotes. Not data. The best you can do here is confirm that a scientific background doesn’t prevent you from getting rich. Science background. But not work as scientists, as CharonY notes.
  8. Not technical enough. How much uranium is there in granite, and how much energy would be released in the decays? https://en.wikipedia.org/wiki/Uranium-238 The decays of the long-lived isotopes at the top of the chain release energy at a rate of 3 microwatts per mole of U-238 (which is much more than you would likely have) from the 6.7 MeV released. The rest of the chain might release 3 or 4 times that amount, so perhaps you have 20 microwatts per mole. In short, no, this isn’t an energy source. piezo
  9. Shape and size are not phase, and speculation is not an appropriate response
  10. ! Moderator Note Posting videos alone is against the rules. Please review rule 2.7 https://www.scienceforums.net/guidelines/
  11. As joigus has already said, there is no such thing as classical entanglement. It is an inherently quantum effect.
  12. Which would have to happen on each detection. With none if these photons diffracting into different orders and only one of the photons being detected. Thousands of times.
  13. Why? Is this based on any physics? The detection rate was such that the expected photon occupancy would have been significantly less than 1
  14. No, not really. The experiment I recall (IIRC the first to claim single-photon) attenuated the light well past the point where you’d expect multiple photons, and multiple photons would have the possibility of multiple detections if they diffracted into different orders, so this could be checked. Plus the possibility of using a detection method that would have an amplitude proportional to the photon number. So care is required in setting up the experiment but not something I’d call “very difficult”
  15. ! Moderator Note No, that’s not what the thread is about, so this is a hijack. Speculations belong in the speculations forum and need to be supported. Opinions are not speculation
  16. Nobody said it was. Strange was pretty specific. But this is all off-topic.
  17. We’re in this thread, not that one. I made my comment earlier today, so a thread locked 9 months ago cannot be an issue. You need to reread the modnotes and perhaps hone your comprehension skills. So you have re-opened a closed thread, and also wish to use speculation to support your idea?
  18. ? You’re answering now. You haven’t been locked out. There was no mention of Stirling engines or coolers in this thread before this, so I don’t know how this pertains to the thread. If you think your proposal isn’t slow and inefficient, you should be able to make your case without bringing up your closed thread. (And no, that’s not an accurate summary of why the thread was closed. The subject matter had nothing to do with it)
  19. I think a device that would work as slowly and inefficiently as this is going to be safe
  20. ! Moderator Note And our rules prohibit making threads to advertise sites. You need to post the information here
  21. The pressure is the same. Increasing the area increases the force, but since energy is conserved, lifting with a 10x larger force happens at 1/10 the rate.
  22. But we're not talking about a gas, we're talking about a liquid undergoing a phase change to a solid "Must" is your requirement then. Whether that actually happens isn't determined by the requirement. After you've turned it all to ice. A mixture of ice and liquid water (allowed to come to steady-state) will be at 0ºC. (similar w/ steam and water at 100ºC)
  23. Yes, it can. But the work is part of the process of the energy removal during the phase change. It doesn't require an additional temperature drop. Before you have water at 0ºC. After you have ice, which has expanded, at 0ºC. The enthalpy of that phase change tells you the energy removal that's required to freeze the water. If you're doing extra work while it freezes, you will have to remove less energy, because the work being done removes energy from the system (as studiot points out, you have to define your system. Any object you lift is outside. Its energy goes up, so the system's energy goes down). I don't think you can conclude the temperature must drop, which would require even more energy to be extracted. OTOH, this is thermodynamics, and there's almost always more than one way to get from state A to state B; "the temperature must drop" is not the same as "the temperature can drop"
  24. This is all happening at 0º or thereabouts; it's a phase change, which happens at constant temperature.
  25. No, the virus has not been tested "longish-term" We already have seen that there are issues with people who have had COVID in the short time it's been around. We don't have a handle on what will happen in the years to come. We know, for example, that chicken pox virus can live in you for decades and flare up as shingles, which is nasty. I don't think we have assurances that COVID will not pose a danger long-term What we do know is that the longer the virus is around and the more it gets transmitted, the greater the opportunity for it to mutate into another variant that will continue propagating. edit: you might help avoid situations like this https://www.washingtonpost.com/nation/2021/05/07/oregon-peoples-church-covid-outbreak/?utm_campaign=wp_main&amp;utm_source=twitter&amp;utm_medium=social "An Oregon church sued over covid-19 restrictions. Now, an outbreak there has sickened 74"

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