Everything posted by swansont
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Alien origin thought experiment.
“throughout” is doing some heavy lifting here. There’s a whole lot of space. “nothing” is what’s plentiful You don’t have to actually be on earth to be noticed.
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Alien origin thought experiment.
Interplanetary travel is assumed here. Eventually you will need to replenish, and no, they are not found anywhere.
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Alien origin thought experiment.
Not even raw materials?
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"Spontaneous" freezing of bottle of Topo Chico
Several factors possibly in play - It could be supercooled, and the bubbles are the disturbances that allow freezing. - What you say about the freezing point isn’t an argument against this - if the system is at -2C, and under pressure freezes at -3 C, and you lower the pressure so the freezing point is -1 C, the liquid is suddenly below the freezing point. So it freezes - CO2 coming out of solution reduces the freezing point depression, so it might now be below the freezing point, as above.
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Does length contraction imply a superposition of particles? [answered: no]
You are free to open a thread in speculations and present evidence to support this claim. Assertions are insufficient, and this is also not in keeping with relativity, so it has no place in this discussion.
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Does length contraction imply a superposition of particles? [answered: no]
Don’t change the subject. You asked about superposition and relativity, not about the block universe interpretation. If you want to ask about the block universe, open a new thread.
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Does length contraction imply a superposition of particles? [answered: no]
Just as there are different kinetic energies; it depends on who does the measuring. Length, like kinetic energy, is a relative quantity. Two measurements by two different observers does not mean anything is in two positions at once, just as it doesn’t have two speeds at once. A superposition is measured by a single observer.
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Does length contraction imply a superposition of particles? [answered: no]
I don’t follow this. There is contraction for any observer (or frame) moving relative to it. But it’s not true, so any conclusion drawn from it is invalid. Further, the thread is about superposition in relativity; relativity is taken as being true. If you have some alternative to SR, like a concept of intrinsic length, it needs to go in a thread in speculations
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Does length contraction imply a superposition of particles? [answered: no]
You’re taking “observe” literally. It’s a frame dependent quantity. KE is a relative property, just as length is. Why do you accept one but not the other? It was incorrect.
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Does length contraction imply a superposition of particles? [answered: no]
You would be wrong. How did you get this far in discussions of relativity without knowing this? Also, I will mention again that you continue to avoid answering my question about kinetic energy Your OP said nothing about this. No, the length depends on who observes it, as it always is with relativity. There is no intrinsic length.
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Alien origin thought experiment.
If they aren't strong enough to challenge us and we are prone to be belligerent, how is it in their best interest to reveal themselves?
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For the first time in 12 years tourists are in space
Did you mean 12 weeks? Weren't there tourists in space (briefly) back in October? I know Shatner played Captain Kirk, but he still counts as a tourist.
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Alien origin thought experiment.
And how do you know "something stealthy" hasn't? Because you saw something that isn't (and has never been claimed to be) stealthy? To rebut the existence of stealth spacecraft, you have to be seeing the stealth craft. The ISS isn't one. It's like claiming that seeing a white horse proves that brown horses don't exist. I don't. That misses the point, which is it might end badly, and some people/beings might want to minimize risk. I also wear my seatbelt when I drive my car, even though I don't know that I will get into an automobile accident.
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Information Paradox
! Moderator Note Discussion on emergent phenomena has been split https://www.scienceforums.net/topic/126248-what-does-emergent-mean-in-a-physics-context-split-from-information-paradox/
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Alien origin thought experiment.
Does it? Can you know ahead of time how somebody else will react? Are you willing to ignore the mountain of evidence of such scenarios ending badly? IOW, does your self-confidence that you will be welcomed as a liberator play much of a role? That didn't work out the last time I heard that phrase.
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Alien origin thought experiment.
Sometimes is the key. If half the time you get a nice reception and the other half you get punched in the face, it's not very long before you have a bloody nose. Discretion is the better part of valor, as they say.
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Alien origin thought experiment.
Humans sometimes respond to new things with violent opposition. It's not a unique behavior.
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Alien origin thought experiment.
Where is "better" claimed? All I see is "more advanced" "The Day The Earth Stood Still" comes to mind.
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Alien origin thought experiment.
How would we know? Anyway, https://en.wikipedia.org/wiki/Misty_(satellite) That doesn't actually support the argument.
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Does length contraction imply a superposition of particles? [answered: no]
Superposition refers to quantum states, or the addition of certain quantities. Length is neither of those. To any observer, a length has a single value. A quantum superposition is a quality of the particle or system in question and choice of basis states, and does not depend on the observer. The followup to this is: Is location an eigenstate? No. So there is no quantum superposition. As I believe you've been told before, length is not an intrinsic/inherent property; you keep treating this as some length having multiple values, and I think I've pointed out to you that we can look at the kinetic energy of a particle, which is another relative value. If you're at rest with respect to the particle, it has no KE. If there is relative motion, the KE is nonzero, and that value will depend on the relative speed, so it can have any positive value. But this doesn't seem to cause any conceptual issues (or maybe it does?), while length does.
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Making Fusion Pay
The total output is 40 MW, but only about ~27 MW could be used; ~13 MW is carries away by neutrons And using any of that 27 MW would likely be counterproductive, since it would tend to cool the plasma down, requiring more input.
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The next pandemic : What have we learned ?
The US used to mandate draft registration (still does) and military service if your number came up. Seems to me putting yourself in harm’s way in service of your country would get more pushback than efforts to protect you, but this is where we are, I guess.
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Making Fusion Pay
That would be dissipated from the system, yes. It’s the energy generated from fusion. From the link I found, you’d retain about 20% of that 16 MW. The neutron losses are presumably because tritium is used
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Making Fusion Pay
I'm not following the math here How does 16 MW output produce 50 MW of waste heat? I don't think you are doing a proper accounting of the energy here. https://www.euro-fusion.org/faq/top-twenty-faq/how-much-power-is-needed-to-start-the-reactor-and-to-keep-it-working/ The power required to keep a reactor working is an interesting question. Energy input is required to keep the plasma hot, because most of the energy produced by fusion is carried away by the neutrons. However 20% is carried by the helium nuclei, which remain within the plasma, so it is possible to reach a point called ignition, at which the production of hot helium is enough to sustain the plasma and the external energy sources can be turned off. It is not clear yet however whether that will be the optimum operating regime in a power plant – being slightly below ignition may give better control of the reactor (while still producing plenty of hot neutrons). So the 16 MW output is mostly radiated away as neutrons - largely unrecoverable, and also a problem* There's no electricity produced anywhere in this process. They haven't gotten to the point of a self-sustaining reaction, where you can turn off the input thermal energy, because (from the numbers above) you'd need to generate ~120 MW for that to happen. And you need to generate more if you want to start siphoning some off to generate electricity. *fusion is sometimes touted as being clean, radiation-wise. The fuel itself will not be more radioactive, which is a leg up on fission, but these neutrons will activate the containment vessel. Yes. This is another issue not accounted for in the math. Q=1 would be a PR milestone, but not an indication that fusion power is around the corner.
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The next pandemic : What have we learned ?
I don't think this a matter of "forgetting" human rights. Governments have to be empowered to enforce isolation or even just mask mandates, and then have the fortitude to carry out the required actions, childish public reactions be damned. edit: this requires that they listen to the scientists, even when this means updating the response in light of new information.