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Everything posted by swansont
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What is the marker? A line is not a physical object.
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Things you know should be in the trash bin, but you can't put them there.
swansont replied to grayson's topic in The Lounge
The trash bin is for topics that are also rules violation of some sort. Not for failed proposals. -
You’d have to have something in the space to be able to observe behavior in order to tell.
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PE is not only for gravity. Any conservative force will work, i.e. there is no dissipative force, such as friction. Electrostatic forces and springs are two prominent examples
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The conversion of PE to KE (or vice-versa) depends on the internal force that’s present. An object under constant acceleration will convert at a different rate than acceleration from an inverse-square relation. You should be able to solve for KE or PE as a function of time, for whatever circumstance you have
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It’s the slope of the function, y = f(x)
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Safety note: these green lasers can “bleed” a lot of IR if there is no IR filter and can be an eye danger since your eyes don’t have a blink reflex for the IR, and there’s a lot of IR power relative to the green light. https://www.technologyreview.com/2010/08/12/121205/the-danger-of-green-laser-pointers/
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This is moot, since fusion does not deal with significant amounts of bulk material. It also depends on the material and wavelength. Some materials are quite transparent at certain laser wavelengths. Fiber optics depends on this But you don’t want the EM radiation to penetrate, you want it to exert pressure. “NIF does this by amplifying and focusing 192 laser beams onto a tiny hollow metal cylinder at the centre of which is a peppercorn-sized capsule containing the hydrogen isotopes deuterium and tritium. X-rays generated from the walls of the cylinder blast off the outer surface of the capsule, forcing the rest of it inwards thanks to momentum conservation and causing the deuterium and tritium nuclei within it to fuse – in the process releasing alpha particles (helium nuclei), neutrons and lots of energy.”
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It may be difficult to tie a single event to climate change, much like you can’t tell for sure that seatbelts saved a life in certain accidents. But it becomes clearer when you look at the statistics of all the events.
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Reintroduction of Quantum Field Theory into modern science
swansont replied to RossJ's topic in Speculations
It’s the gravitational potential - the height change is the major contributor, not the change in g - and atomic clocks don’t rely on radioactive decay. -
Growth rate has been slowing for decades https://www.statista.com/chart/28744/world-population-growth-timeline-and-forecast/
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Derivation of neutrino mass from neutrino scattering...
swansont replied to Orion1's topic in Speculations
That tells you where the scattering event occurred. It doesn’t tell you the neutrino path, because you don’t know where the neutrino originated. You might estimate the angle, but how do you know the momentum of the neutrino? When I was a postdoc, we did an experiment where we knew where the originated, because they came from beta decay in a magneto-optic trap, so the source was localized to a small volume. We couldn’t detect them, though, but could deduce their momentum by detecting the beta, the daughter nucleus, and any orbital electrons that were ionized in the decay process, for decays where all the particles were co- or counter-propagating. -
! Moderator Note Responses to inquiries need to be mainstream science, rather than pet theories, which can only be discussed in their own thread in speculations
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! Moderator Note A. It’s their thread, and B. It’s brought up in the OP
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Why have a fight with a language model that has only a casual relationship with the truth? (And I should take my own advice)
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Planetary Defense: Shielding Earth from Asteroids
swansont replied to Panoptic Perceptions's topic in Science Education
The conditions are not the same, so you won’t get that result. Are you being deliberately obtuse? We weren’t discussing the crew. No, that’s not what the article says. On the other hand, when it’s on the side when our planet completely blocks out the sun, the thermometers plummet to minus 250 degrees Fahrenheit (-157 degrees Celsius). -157 is not in the dark side in sunshine -
Derivation of neutrino mass from neutrino scattering...
swansont replied to Orion1's topic in Speculations
There’s nothing inherent in the equations that says the zero-mass particle must be a photon. i.e. it applies to all zero-mass particles. -
Planetary Defense: Shielding Earth from Asteroids
swansont replied to Panoptic Perceptions's topic in Science Education
The Webb isn’t in LEO You have no reference for “they don't want them to get cold” -
Planetary Defense: Shielding Earth from Asteroids
swansont replied to Panoptic Perceptions's topic in Science Education
And your reference for this is...? What's the point of discussing things if you're just going to make stuff up? -
Planetary Defense: Shielding Earth from Asteroids
swansont replied to Panoptic Perceptions's topic in Science Education
That's not accessible now, though. That's a lander that's not returning. I've seen a study where DNA was stored at temperatures below -20ºC and was stable for 24 months. The units that have only recently been available to the ISS don't get that cold. Once the temperature issue gets solved for LEO, the next issue is radiation. -
Planetary Defense: Shielding Earth from Asteroids
swansont replied to Panoptic Perceptions's topic in Science Education
And how accessible is the moon? -
Planetary Defense: Shielding Earth from Asteroids
swansont replied to Panoptic Perceptions's topic in Science Education
Yes. Perhaps you need to refresh your memory of it. You can’t stay in the shade, and even mirrors heat up. You have to get away from earth to leverage the cold of space. In LEO, where it’s relatively accessible, it’s difficult to maintain something cold. Out where you have the Webb telescope, you can. What’s the point of storing it where you can’t get it?