Everything posted by swansont
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Ground speed of moon on earth
It’s covering more distance by a lot. A geostationary orbit is ~35,800 km in altitude (~42,200 km from center) as opposed to the 6400 km radius. As Janus says, that’s 6.6 times further out, so it covers a circumference 6.6 times as big in the same time - it’s moving 6.6 times faster. But its ground speed is basically zero.
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How to Convert Diffusion Rate to Hertz
Frequency is the reciprocal of period. To have a period, it needs to be periodic. Just because there are units of inverse seconds, it doesn’t mean there is a frequency.
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Can I delete such folders from C disk, example "02eeb6d92f89e33ba2ea06"
Or you change the file name (e.g. append ‘A’ to it) to see what happens, which is easily changed back if there’s a problem with a program.
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Which of these is the best propulsion for Von Neumann probes?
It’s likely that the propulsion system, like these probes, has not yet been realized.
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Which of these is the best propulsion for Von Neumann probes?
Vaporizing liquid microthruster https://www.sciencedirect.com/science/article/abs/pii/S0924424799003891 “Experimental testing produced thruster force magnitudes ranging from 0.15 mN to a maximum force output of 0.46 mN” That’s not very much thrust. AFAIK resistojets are used for station-keeping, not propulsion. Why does it have to be a Non Neumann probe? Is that in any way relevant? https://beyondnerva.com/resistojet-electrothermal-thrusters/
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Is CPT symmetry still valid for macroscopic physics?
The left target gets no light. The target on left was the target on the right before you apply the P transformation. It was absorption. It become emission.
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is RFID blocking wallet a gimmick?
I know I didn’t make the charges, and reported them to the card issuer. They investigated, and refunded the money. And I said waiter, not bartender. It was at a restaurant. —- “There has still to this day not been a report of a single real-world crime that an RFID blocking product would have stopped.” https://www.digitaltrends.com/cool-tech/are-rfid-blocking-products-worth-your-money-we-asked-an-expert/ —- I just read that zero liability is now US federal law. Not sure when that was enacted. Also, RFID transactions are encrypted, so you’d need to use your skimmed info quickly, or the code wouldn’t be correct. Right. Which is why a method that doesn’t require you to hand over your card to someone was developed.
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is RFID blocking wallet a gimmick?
IIRC, I had no liability when someone stole my credit card info (waiter at a restaurant was the likely culprit)
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Gravitational waves (split from Wave-Particle Duality)
Yes, you can have as many nonexistent photons as you want. Dirac’s quote is from 1927, so it’s not like the whole idea of bosons had been developed very much.
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is RFID blocking wallet a gimmick?
And you aren’t liable for most of it, in the US. You’d owe at most $50 per card, and some cards have zero liability. That puts the burden on the credit card companies to have decent security measures. One card I have texts me for approval if the purchase breaks a pattern
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Is astrology a science
The Greek right to bear serpents.
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Is CPT symmetry still valid for macroscopic physics?
Why would there be stimulated emission under time reversal?
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Is astrology a science
I’m a Gemini, so I never know what to expect
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Is CPT symmetry still valid for macroscopic physics?
No. With the t reversal, the excited atom in the target emits a photon.
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NANOGrav announces evidence of gravitational wave background
That suggests that they dissipate, which is probably the wrong way to view the classical field A static field exists. Perturbations/fluctuations happen, which are variations in time. No change unless the source of the field was somehow changed. Waves obey superposition.
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Is CPT symmetry still valid for macroscopic physics?
That’s only time reversal symmetry. You haven’t applied the parity transformation.
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Can I delete such folders from C disk, example "02eeb6d92f89e33ba2ea06"
I believe they are asking if deleting the files will cause a problem, e.g. if they are necessary for some program or the operating system.
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Is CPT symmetry still valid for macroscopic physics?
You have asserted this, but I don’t see how you get there from transforming x —> -x That transform would flip the experiment - its mirror image. IOW, I don’t think you’ve done the P transform properly. Repeating your conjecture is not sufficient.
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is RFID blocking wallet a gimmick?
Yes, because of pushback from customers who put convenience above security.
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is RFID blocking wallet a gimmick?
That’s probably why it’s not seen there, since the PIN wouldn’t be something you can scan. In the US, AFAIK PINs are not required. Yet. It used to be that transactions at the self-checkout at my grocery store were limited to $50 and they checked your ID if you went to the regular checkout, but they stopped doing that after a few years. (edit: if I want cash back with my transaction, the self-checkout wants a PIN if I use the chip)
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NANOGrav announces evidence of gravitational wave background
One of the things I read is that the pulsars are only measured every few weeks, which works because the GW frequency is so low. That way they can monitor multiple pulsars with their telescope time. Also explains why it took years to get the data, since the period of a 31.5 nHz wave is a year.
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is RFID blocking wallet a gimmick?
I’ve read that UK/European standard is to have a PIN you enter for these transactions. Is that correct?
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Why Is Paganism Rising?
Also depends on how the poll is worded.
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Why Is Paganism Rising?
I think that any small category of people have benefitted from the ability to connect. You have disaffected people in the majority or plurality group going through the motions who become aware there is an alternative that’s a better fit. It’s a bit like buyer’s remorse, but you’re finding out after the fact, and you can trade in your religion (or belief). Also the fact that you can do so online means you don’t face the same pressures of IRL interaction until (possibly) after locating a group that fits you. If you have somewhere to go, being shunned by your former group might be palatable.
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OceanGate Submersible Goes Missing During Titanic Dive
Why would it be momentarily huge? It’s not going to be bigger than the external pressure. If any remains were recovered, I suspect they would be kept away from the public eye.