The black hole charlatans

When you read the Einstein digital papers, you understand how gravity works. Einstein said things like “the curvature of light rays occurs only in spaces where the speed of light is spatially variable”. Note that he never abandoned this, and he never said light curves because it follows the curvature of spacetime. Instead he said a gravitational field is a place where space is “neither homogeneous nor isotropic”, he referred to Huygen’s principle, and he talked about “the refraction of light rays by the gravitational field”. So did Newton, see…

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Misconceptions in gravitational physics

I think it’s safe to say that there are some misconceptions in physics. The issue of course, is how many. That’s where I part company with your average physicist. He’ll tell you that whilst we don’t understand everything, we do understand some things, such as black holes. Only he doesn’t. Take a look at the Wikipedia black hole article. It says this: “a black hole is a region of spacetime exhibiting gravitational acceleration so strong that nothing - no particles or even electromagnetic radiation such as…

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The information paradox

The information paradox was first mooted by Stephen Hawking in 1976. For an introduction to the subject, see Brian Koberlein’s black holes tell no tales or do they? Then see Hawking’s paper on the breakdown of predictability in gravitational collapse. Hawking said information is lost down a black hole because the quantum emission is completely random and uncorrelated. He also said “this means there is no S matrix for the process of black-hole formation and evaporation”. The S-matrix is the scattering matrix which is to do…

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The Hawking papers

You can find a list of Stephen Hawking’s publications on the Hawking.org website. It starts with his 1965 PhD thesis. This is said to have “borrowed from Roger Penrose's theorem which described a 'spacetime singularity' being present in the centre of black holes”. Penrose was one of Hawking’s PhD examiners. Seven out of Hawking’s first ten papers concerned singularities. Singularities and the geometry of spacetime One of Hawking’s early papers was singularities and the geometry of spacetime dating from 1966. At 91 pages it’s curiously long.…

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Hawking radiation

Everybody knows about Hawking radiation. It’s been on TV. See the YouTube clip from the Channel 4 documentary Stephen Hawking: master of the universe. That’s where Kim Weaver of NASA says black holes offer an ultimate test of the physics of the universe. She says they’re cauldrons of heat and light with jets and particles coming out at half the speed of light, and an enormous amount of stuff going on. She finishes up saying and that’s exciting. I absolutely agree. Because yes, I think black…

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