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Showing content with the highest reputation on 07/12/22 in all areas

  1. The event horizon is a null surface, and as such has a coordinate area, not volume. I'm not sure of the relationship between this area and its angular momentum, all else being equal. Yes, a rotating black hole (Kerr metric) contains a ring singularity. A charged black hole (Reissner-Nordsrom metric) cannot have its charge exceed its mass. So no additional charge can be added to one that is sufficiently close. The mass in unaffected by this, and the event horizon 'radius' is determined by the mass. If there is a black hole with charge equal to its mass, you get a naked singularity, which is a singular solution to the metric. So (just thinking out loud here, not an authority), if you have a super-positive charged black hole near this limit, a negatively charged particle would be more attracted to it than a neutral particle. Thus I would think there would be a second charged event horizon for the negatively charged thing that is further out than that of say a neutrino. Also, the EM potential would be so steep that it would probably rip apart (an EM 'tidal' effect) neutral things like a neutron, pulling it into charged components and accepting only the one.
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  2. But it doesn't blow the rest of the gas away. For example, our sun has much more mass in it than just the core, which has only about 10% of the sun's mass in it. Radiation pressure is relatively weak; you need a large photon scattering rate to cause appreciable acceleration. So you will blow gas away, but it depends on the luminosity of the star and what the gravitational acceleration is. At some luminosity you blow gas away at some distance from the star because gravity drops off, but gas inside that point still feels a net attraction. "The Eddington limit is the point beyond which a star ought to push itself apart, or at least shed enough mass to reduce its internal energy generation to a lower, maintainable rate. The actual limit-point mass depends on how opaque the gas in the star is, and metal-rich Population I stars have lower mass limits than metal-poor Population II stars." https://en.wikipedia.org/wiki/List_of_most_massive_stars#Eddington_mass_limit
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  3. I presume it's supposed to turn despite no net torque applied. That can't work. Sure, you have a force at application points pushing it counterclockwise, but the torque applied between the plate and same points of application balance that, pushing it clockwise. No motion will result. Rule 1: Perpetual motion machines violate physics. Can't be done.
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  4. I did begin with a card scraper before starting my 4-5 hour sanding session with headphones full of music and nostrils full of fresh air.
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  5. I think it primarily means if the actual pregancy is causing physical medical harm to her life. Not sure if suicidal ideation as the result of one is covered under that law. It seems that none do. 5 make no exception for rape or incest. https://www.politico.com/news/2022/06/24/abortion-laws-by-state-roe-v-wade-00037695 I think one of the real issues will be women who miscarry and are subject to an invasive investigation under suspicion of voluntary induction rather than a tragedy for them until proven as naturally caused. Either way, involuntary or voluntary, it's a serious state breach of bodily autonomy.
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