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swansont

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Everything posted by swansont

  1. swansont replied to beecee's topic in The Lounge
    ! Moderator Note Not science news. Moved
  2. In classical physics, one can often ascribe a trajectory to the solution using energy. Not so much with QM. The kinematics equation s = v0t + 1/2 at^2 explicitly has a velocity in it, but there is no corresponding QM equation.
  3. Not really. Look at how many times he cites himself. That can be a sign of bootstrapping nonsense. When you're building up a house of cards it doesn't matter if you have one or two solid pieces in the foundation.
  4. There is generally no interaction between entangled particles. It’s not obvious to me that gravitational time dilation would have any effect on the entanglement.
  5. Ferrying water into space is not evaporation. You would be moving a relatively small amount of thermal energy, that won’t cool anything, at the cost of a lot of propulsion energy. Escape velocity is ~11 km/s, so you need 1/2 v^2 of energy, minimum, to get 1 kg of mass away from the earth. Roughly 6 x 10^7 joules. Moving a kg of water doesn’t cool anything off - no reduction in temperature. If you remove a bucket of water from a pool, the pool isn’t any cooler. It’s marginally easier to heat up for the same energy being added. You would have to heat the water up, and at 4.18 kj/kg-C, it’s going to be a lot less than the energy cost of the propulsion.
  6. Bad stretch of weather? Pollution? Smoke of a distant fire?
  7. Not motion, as such. There’s no trajectory information there. Location and momentum (probabilities) and energy and angular momentum (eigenvalues) can be found.
  8. The Google results for "Spin Conjugate Dynamics" gives ~10 results and the top 3 are from the author of the paper (and I think that other hits are referencing the paper). That's...not good. IMO it's not the writing quality, as such, it's fiction vs non-fiction.
  9. I've not run across these terms before. The Google results for them suggest they are made up.
  10. No. There's no physics there, just some terminology tossed together, devoid (as far as I can tell) of any real meaning.
  11. And there's a limit to what we can "see" and that may or may not tell us what something "looks like" (which is what the OP asked) e.g. the size of electron from scattering experiments is smaller than (IIRC) 10^-18m. We can't measure a smaller number We can get an image from sonar or radar, but again, the size and shape we reconstruct may not reflect reality. It wouldn't tell us what color the object is (Something that doesn't preferentially absorb a particular wavelength range of photons isn't going to have a color). It doesn't tell us what it looks like, which is a visual limitation. "What does it look like" is a quasi-classical inquiry, and like other aspects of classical physics, it loses meaning at small scales.
  12. Not only are the trio of orbitals symmetric, but you don't have a preferred axis in the absence of some external field. So the orbitals can be oriented in any direction in space. You can't say which p orbital the electron is in, so it's in all of them until you measure. IOW, you don't have an intrinsic electric dipole moment, as I posted earlier. Going back to the OP, these particles don't really "look" like anything since we can't form an image of them. Even the Sr ion doesn't "look" like anything based on the light it's giving off. A neutral Sr atom is a few hundred pm in radius, but the light being emitted is around half a micron. You wouldn't be able to determine the size based on that light. What it "looks" like really only makes sense for objects where diffraction is not important. We can use other particles that can have much shorter wavelengths, e.g. electron microscopes, in order to form an image. We can get other information by reconstructing what happens with e.g. scattering experiments. But because of quantum mechanical effects, everything will have a wave behavior, and the notion of what it "looks" like loses meaning. We talk about how it behaves — how it interacts — and what its properties are. Elementary particles are depicted as balls in diagrams because that's a way to visualize interactions. You could look at Feynman diagrams to see various interactions between particles. But it's like a schematic of a circuit — that's not necessarily what the actual circuit looks like,
  13. In the US, the EPA classified CO2 (back around 2007, confirmed by supreme court ruling) as a pollutant and therefore had the authority to regulate it, but there was pushback. The supreme court ruled in 2014 that the EPA could regulate carbon emissions. But there was never any will to do anything for the environment under the Trump administration. Trump reversed Obama policies on the matter (as he did on so many issues)
  14. I don't see any physics in there. It's word salad.
  15. Relativity is a notion in physics that some variables depend on the frame of reference in which they are measured. Einstein developed the theories of special and general relativity to deal with mechanics and its dependence on reference frames (GR incorporates gravity) As a theory it makes predictions and has been extensively tested, and is supported by these experimental results. It's not an ideology.
  16. The electric dipole moment of a neutral atom in zero field is zero https://journals.aps.org/pr/abstract/10.1103/PhysRev.174.125 "The observation of an electric dipole moment (EDM) in an atomic system of well-defined angular momentum would be direct evidence for violations of both parity and time-reversal invariances."
  17. Vacuums do not pull matter. Colloquially put: pumps don't suck. The atmosphere blows.
  18. No, it doesn't. It might reflect more on the business, if the green product is less profitable, and that's why it is not being offered. Again, no evidence presented for your narrative. "lying for the environment" seems to be your description here (so you'd be guilty of the same hyperbole you are decrying), and you have not shown it has crept into research - no links to actual journal articles, as far as I can see. You've shown it has crept into PR, and I'm wondering why anyone is shocked that PR uses hyperbole. It's true in the US, too, as far as my experience goes. There's this myth that "the market will provide" and people that preach market solutions for problems, rather than government solutions. But the pure capitalism that some worship only cares about maximizing profits. I think it's a failure of having large corporations and conglomerates. A small company might see value in an incremental increase in profits from one product, while a large company is less likely to. Also, if you already have a large market share, you might be less inclined to care about consumer loyalty, if there aren't alternatives to your product. Tying in with the topic: Tesla is an example of a company making a (potentially) "green" product, but they had to start up on their own, probably because existing car companies didn't want to cannibalize their own sales. But we see that people will buy such products if offered. Hybrids, too, but they were introduced because the US government forced the issue by raising gas mileage standards, and companies needed some cars with great mileage to bring the average up. And lo and behold, they sell. Demand is there. Tesla had a multi-year waiting list for their cars at the beginning; demand far exceeded supply. Hybrid electric + EV sales keep increasing
  19. Scuffing your feet on the carpet while holding a fluorescent bulb is another way to pass the time leveraging static electricity (My childhood was pre-Star Wars, so we didn't know to pretend it was a light saber)
  20. ! Moderator Note How about we return to the topic, and not post otherwise
  21. That’s not how taxes work.
  22. Closing on 1000 posts and 5 years here; that’s hardly a newcomer. And there’s plenty of quality science given in response to dubious claims. The main issue is that the feedback wasn’t incorporated into the discussion.
  23. swansont replied to Uvindu's topic in Physics
    The question was “Does Energy depend on frames of reference?” not whether it’s conserved within a frame of reference. Yes, total energy depends on the reference frame.

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