Photo: Albert Einstein |
Photo: Roman Mager via Unsplash |
Though most of us would sell our in-laws to achieve a tenth of what he did, his science wasn’t perfect either: while he was a founder of what came to be called Quantum Mechanics, he disagreed with other scientists about what it all meant, and he once thought he had proved that gravitational waves could not exist (an anonymous reviewer of his paper found his mistake and set him straight). Yet Einstein did create one thing that, as far as we can tell, is as correct as anything can be in science. That is his theory of gravity, called General Relativity.
He presented the theory to the world over four consecutive Wednesdays in November 1915 in lectures at the Prussian Academy of Sciences. Einstein was by then well respected in European physics circles, and one can imagine more than one person in the audience that November thinking that he’d gone bonkers. Einstein’s theory purported to replace the hugely successful 1687 gravity theory of Isaac Newton, which posited gravity as an attractive force between masses, with one where gravity was a result of the curving and warping of space and time by massive objects. And the evidence for this new theory? It managed to account for a tiny discrepancy of 120 kilometers per year in the spot where Mercury makes its closest approach to the Sun. The concepts behind this new theory were so radical and unfamiliar that it was said that only three people in the world understood it.
Yet a few people, like David Hilbert in Germany, Willem de Sitter in the Netherlands, and Arthur Eddington in England grasped the startling implications of this theory...
Will this perfect record hold up? We do know, for example, that the expansion of the universe is speeding up, not slowing down, as standard general relativity predicts. Will this require a radical new theory of gravity, or can we make do with a minimal tweak of general relativity? As we make better observations of black holes, neutron stars and gravitational waves, will the theory still pass the test? Time will tell.
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Source: OUPblog