On September 14, 2015, two lengths of vacuum-sealed steel pipe — one in the Louisiana swamp, one in the Washington high desert, each four kilometers long — flexed by an amount smaller than a thousandth the width of a proton. That flex was a gravitational wave: a ripple in spacetime itself, arriving at Earth after…
How a patent clerk’s thought experiment about falling elevators became our best description of gravity, black holes, and the shape of the universe itself in the . Also read: 1905: Einstein’s miracle year In 1915, Albert Einstein handed physics a strange new idea: gravity is not a force reaching out across space. It is the…
In the spring of 1905, a twenty-six-year-old patent examiner in Bern, Switzerland, was reviewing applications for mechanical inventions during the day and rewriting the foundations of physics at night. He had no laboratory, no university post, and no research group. What he had was a stack of unresolved problems that the physics of the nineteenth…
