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Everything posted by swansont
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Not even that long, I suspect. Dense-packing the trees seems to stimulate growth for the few years observed, but what happens as the trees (literally) branch out? Will the proximity impede growth? What happens as their root systems start interfering with each other - will you run into issues if water is scarce?
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True for a single magnet, because you induce a magnetic field in the material, but your system would induce opposite fields which would tend to cancel. i.e. the field halfway between the magnets is small, so the induced field is also small.
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So it depends on M and r. Which means one could say that mass causes gravity.
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I give up. GR can apparently only be explained using GR Every time i look into GR it’s like pulling teeth; I come away convinced that nobody does a numerical calculation because none of the math is ever presented in a way where that’s possible. I’ve read that GR reduces to Newtonian gravity, but have never been able to find a worked example of that, because nothing is ever presented but the tensor mathematics. Along the line of my frustration, I recall a seminar (on Lie algebra, IIRC) in grad school where the prof was asked what the difference was between contravariant and covariant, and the response was something like “contravariant means the indices are along the top” which is true but doesn’t do anything to advance anyone’s understanding.
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And what are the boundary conditions of those sets?
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Do inspiral charged black hole pairs radiate light?
swansont replied to md65536's topic in Relativity
The Coulomb field is static; that’s the 1/r^2 field. EMR intensity drops off as 1/r^2 from a point source, but intensity is the square of the field strength. -
How? Usually there’s only one solution for a given set of boundary conditions.
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“Allows” doesn’t mean these exist. How would one get a gravitational wave absent energy-momentum? (Maxwell’s equations allow EM waves, but classically you aren’t going to get one in a situation where you don’t have a charge somewhere) The scenario has two parts, the earth influencing geometry and the location. You only addressed the latter. Does mass cause a particular geometry to exist? It’s my understanding that it does. The geometry you have depends on whatever mass (as a first-order approximation) you have.
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That wasn’t the whole point, though. The geometry tells the mass how to move, but does it cause the mass to exist?
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Do inspiral charged black hole pairs radiate light?
swansont replied to md65536's topic in Relativity
How does your conclusion follow from the quote? What kind of radiation is it? -
Local ≠ co-located
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Isn’t the sun’s (or earth’s) field approximately a solution to the Schwarzschild geometry? They are equal, but isn’t that a static solution? And if you perturb the energy-momentum, don’t you get a lightlike fluctuation in the curvature? How is it not local? Gravitational waves are a dynamic effect, though. What if we limit ourselves to a static configuration?
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Isn’t the separation of momentum-energy and curvature lightlike? The fluctuations (gravitational waves) propagate at c What’s the curvature of the Schwarzschild solution? I’m confused. “The Schwarzschild geometry describes the spacetime geometry of empty space surrounding any spherical mass” https://jila.colorado.edu/~ajsh/bh/schwp.html
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This implies that lightlike separations are not causal.
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What is the algebraic form of that component?
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