A Satellite Mishap Is Letting Physicists Test Einstein's Theory of Relativity

When life gives you lemons, make lemonade, right? That, at least, is the motto the European Space Agency seems to have embraced with respect to two wayward satellites, which are being repurposed to provide the most accurate assessment yet of how gravity affects the passage of time. »11/14/15 5:30pm11/14/15 5:30pm


Yes, Time Travel Is Possible; Here's How

Time travel's been one of man's wildest fantasies for centuries. It's long been a popular trend in movies and fiction, inspiring everything from Charles Dickens' A Christmas Carol to H.G. Wells' The Time Machine to the Charlton Heston shrine that is The Planet of the Apes. And with the opening of Interstellar »11/05/14 6:28pm11/05/14 6:28pm

A Brief History of Scientists Hunting for Time Travelers

Time travel is possible—or at least a lot of serious physicists say so. It's probably not possible to pull it off in a souped-up Delorean, but there are wormholes, Tipler cylinders, and other Einstein-inspired theories for how it could work. Which raises the question: Why haven't we met any visitors from another time? »10/09/14 3:39pm10/09/14 3:39pm

In Cosmos, The Only Thing More Important Than Evidence Is Imagination

The universe, they say, isn't just stranger than we imagine. It's stranger than we can imagine. After three episodes focused on matters solar and mundane, from the evolution of life to the orbital dynamics of comets in our little flat circle of spacetime, episode four tackles the limits of cosmic reality far beyond… »3/31/14 12:20pm3/31/14 12:20pm