Are fundamental particles singularities in the general relativistic sense?

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Point particles have mass.
Point particles are dimensionless.
Would it stand to reason that point particles are infinitely dense and, thus, singularities?
 
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It would, which is why point particles don't exist in reality, but are simply abstractions so we can simplify our calculations.

Real particles are quantically "smeared" across a given volume of space, which makes their density finite, but you're better off asking about it in the quantum mechanics forum.
 
FAQ: Is a fundamental particle a singularity in the general relativistic sense?
No. If it was, it would be a black-hole singularity. But it is believed that microscopic black holes would evaporate into photons, whereas electrons, for example, do not seem to. The time a black hole takes to evaporate becomes shorter as the black hole gets smaller. When the black hole has a mass equal to the Planck mass, which is about 22 micrograms, the lifetime becomes on the order of the Planck time (or a few thousand times greater). All known fundamental particles have masses many orders of magnitude less than the Planck mass, so there is no way they could have long lifetimes if they were black holes.
 
I asked a question here, probably over 15 years ago on entanglement and I appreciated the thoughtful answers I received back then. The intervening years haven't made me any more knowledgeable in physics, so forgive my naïveté ! If a have a piece of paper in an area of high gravity, lets say near a black hole, and I draw a triangle on this paper and 'measure' the angles of the triangle, will they add to 180 degrees? How about if I'm looking at this paper outside of the (reasonable)...
From $$0 = \delta(g^{\alpha\mu}g_{\mu\nu}) = g^{\alpha\mu} \delta g_{\mu\nu} + g_{\mu\nu} \delta g^{\alpha\mu}$$ we have $$g^{\alpha\mu} \delta g_{\mu\nu} = -g_{\mu\nu} \delta g^{\alpha\mu} \,\, . $$ Multiply both sides by ##g_{\alpha\beta}## to get $$\delta g_{\beta\nu} = -g_{\alpha\beta} g_{\mu\nu} \delta g^{\alpha\mu} \qquad(*)$$ (This is Dirac's eq. (26.9) in "GTR".) On the other hand, the variation ##\delta g^{\alpha\mu} = \bar{g}^{\alpha\mu} - g^{\alpha\mu}## should be a tensor...

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