Everything posted by exchemist
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Internal and External IP Address Query
Thanks, that seems clear enough. I have found the internal and public addresses of the laptop. For completeness, do you know how I can get the IP address of the router?
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What is the behavior of a magnet floating in a superfluid that rotates indefinitely?
The induction is due to the magnet, right? So the magnet will lose energy. If the fluid is frictionless, the vortex can continue, since the slowing down of the magnet will not slow down the rotation of the fluid.
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The United Nations and I both believe in renewable energy.
What? There has not been a literal passing of infinite time, according to the dominant cosmological model. The universe is thought to be ~14bn years old: https://en.wikipedia.org/wiki/Age_of_the_universe
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Was Einstein a Christian?
I had always thought "German Physics" was specifically antisemitic and that's why it was anti-relativity - and suspicious of QM. Wasn't Heisenberg labelled a "white Jew" at one stage, because of QM?
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Was Einstein a Christian?
The Szilard letter, warning Roosevelt not about fission but specifically of the danger of Nazi Germany getting an atom bomb, was written by Leo Szilard, in collaboration with Edward Teller and Eugene Wigner. Szilard persuaded Einstein to sign it, correctly believing that would carry more weight with Roosevelt and those advising him. Far from warning of the dangers of nuclear fission, the letter insisted it was vital the USA should start its own bomb programme. This became the Manhattan Project, which took over from the already existing but underfunded British Tube Alloys programme. Einstein ran from the Nazis because he was Jewish, as did so many eminent other physicists in continental Europe. Hitler stupidly created a massive brain drain of scientific talent. So that was simply rational self-preservation on Einstein's part. I'm not sure where you get this about him uniting people. How do you think he did that?
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The United Nations and I both believe in renewable energy.
But the universe is a closed system, surely? After all, there is nothing "outside" it. So while Schrödinger's remarks make perfect sense, they don't tell you anything about the universe as a whole. The argument you cite about gravity looks wrong to me. No gravitational process reduces net entropy, so far as I can see. I wonder if the author of the Noema article has confused entropy with simple "disorder" in distributions of matter. Entropy is "disorder" of a specific kind, namely disorder in the way energy is distributed. Gravitational attraction may pull things together, but this converts potential energy to kinetic, which ultimately is converted to heat, which dissipates, increasing the disorder in the energy involved. I have never heard of gravity being described as anti-entropic. Do you have a source for that?
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The United Nations and I both believe in renewable energy.
If you read your Wiki link, you will see why this c.19th “paradox” does not trouble modern cosmology. According to the current model, the universe is not infinitely old, and so it has not had time to “run down” to thermodynamic “heat death”. So the laws of thermodynamics are fine.
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What is the behavior of a magnet floating in a superfluid that rotates indefinitely?
Because the induction will act as a brake on the rotating magnet. Just like regenerative braking on a locomotive or an electric vehicle. The bulb radiates electromagnetic energy, which comes from the kinetic energy of rotation of the magnet. So it will slow down and stop.
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Was Einstein a Christian?
I think this is a bit naïve. You seem to be thinking that because Einstein's life, actions and writings were (mostly*) thoughtful and honourable, he displays Christian values. But we see around us every day evidence that many people who consider themselves good Christians support all manner of unworthy causes and actions. One example that springs to mind is the US Evangelical support for Trump, who is quite obviously a thoroughly evil man. So I can't see that the correlation between personal goodness and Christian belief is particularly strong, as rule. *Einstein had affairs while married.
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WHO declares mpox epidemic public health emergency of international concern
I see the WHO has been at pains to point out this is not another Covid. The disease seems to be contagious, so won’t be passed without physical contact.
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The United Nations and I both believe in renewable energy.
Don't neglect ammonia. This is being heavily researched for ships. You can burn it, producing water and nitrogen. Considering planes, it can be stored much more easily than hydrogen as at room temperature it liquefies at a pressure of only 10bar, whereas hydrogen has to be stored as a very highly compressed gas, adding to the weight. Issues to be managed are toxicity of the gas and potential NOx emissions when burnt. Ammonia would be generated from green hydrogen, so in effect it's really just an alternative form of hydrogen that is easier to store.
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Photons and light
Britannica disagrees:https://www.britannica.com/science/light As I said earlier in the thread, the term light is not used only to denote a perceived sensation but also to refer to the radiation itself.
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Photons and light
In science the term “light” refers to EM radiation in the visible region of the spectrum, not just the sensation we perceive. So light is composed of photons.
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WHO declares mpox epidemic public health emergency of international concern
This may be one case where being old helps. I’ve been vaccinated against smallpox, which I gather confers some protection.
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Explanation of Raised Plateaux Inland from Ocean Margins
That’s interesting. So the basic idea is not entirely new, then. I suspect the novelty is the idea of this rolling vortex propagating away from the spreading centre due to this Raleigh-Taylor instability that they have modelled. Perhaps that takes care of the heat flow issue you refer to.
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Radiacode: pocket-sized radiation detectors. Is it worth it?
How interesting. Jolly useful if a Russian invites you to tea! Could be interesting to see how much one is exposed to in the streets of Aberdeen, or in the basements of houses in Cornwall. Although, thinking about it, if this thing only detects gamma radiation it might not help in those contexts.
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My 21st Century Automobile Dream: Preston Tucker had his dream and Big Three shot it down.
Because you scornfully ask whether EVs have not to be fun to drive, and must be cramped, rough-riding “econoboxes”. You are implying that is what they are like and dismissing them as unattractive on that basis. You have not checked your facts and are merely reciting ill-informed prejudices. There are electric versions of a large number of cars these days and there are some, e.g. models from Tesla, that are luxurious, silent, and offer neck-snapping acceleration.
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Help Figuring out a Physics Brain Teaser... Closed Loop Pulse Propulsion
Being offensive is no substitue for understanding physics. Your attitude is so obnoxious that I don’t see any point in pursuing this bullshit. I’m out.
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Rock salt...
I would expect salt to draw moisture out of any living cells it comes into contact with by osmosis, killing them. It would thus have some antiseptic action against bacterial cells, but I suppose it would also do some damage to the tissue exposed in the wound. Whether that would materially slow down healing I don't know.
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My 21st Century Automobile Dream: Preston Tucker had his dream and Big Three shot it down.
OK so it’s yet another thinly disguised attempt to pour scorn on the change to a non-fossil fuel dependent society. What a tosser you are. There are plenty of high-performance and luxurious EVs, though naturally not built nearly as badly, as unsafe, or handling as diabolically as some of the dreadful American models you mention. Just go on any car maker’s website.
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My 21st Century Automobile Dream: Preston Tucker had his dream and Big Three shot it down.
So what?
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anyone having trouble posting, quoting, etc due to aggressive ads?
Yes, this was explained to us before as being something euphemistically termed a "vignette" ad. The idea is it intrudes into what you are trying to do, to force you to cancel it in order to get back to where you were. Bloody rude and irritating: a classic example of Cory Doctorow's concept of enshittification in action: https://doctorow.medium.com/my-mcluhan-lecture-on-enshittification-ea343342b9bc "We’re all living through the enshittocene, a great enshittening, in which the services that matter to us, that we rely on, are turning into giant piles of shit."
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Help Figuring out a Physics Brain Teaser... Closed Loop Pulse Propulsion
That should not amaze you. You have not described the setup very clearly, especially the part concerning the “tether system”, which is where I think your analysis is in error. The capturing of these slugs and redirecting them will create an impulse on the spacecraft that will cancel the recoil due to the railguns (or coilguns - you are not consistent in your use of terms) and create a reaction that will move the spacecraft back again in the opposite direction. But one doesn’t really need to analyse each step since as @swansont points out, applying the principle of conservation of momentum to the whole system tells you there will be no net change in velocity once the cycle is complete. If you think this is wrong or misses the point then I suggest explaining in more detail how this “tether system” is meant to function and we can analyse that, as I feel sure this is where the mistake arises. This business about 20m and 1m is not explained at all - what’s going on?
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Explanation of Raised Plateaux Inland from Ocean Margins
Yes it isn’t that easy to follow, but the diagrams in Fig 6 help a lot. Take a look at those.
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Explanation of Raised Plateaux Inland from Ocean Margins
This is not about escarpments adjacent to a rift. It is about elevated plateaux that lie far inland from an opening ocean. If you look at the diagrams it may become clearer.