Thursday, September 19, 2013

Maybe Space-Time is an Illusion

From Mother Jones:
Via Alex Tabarrok, Quanta magazine reports on a decades-long effort that has recently produced a radically simplified way of calculating quantum interactions. Instead of adding up millions or billions of terms, you simply sum the volumes of the pieces of a multi-dimensional jewel-like object called a "positive Grassmannian." Its inventors call this object an amplituhedron:
The amplituhedron is not built out of space-time and probabilities; these properties merely arise as consequences of the jewel’s geometry....Encoded in its volume are the most basic features of reality that can be calculated, “scattering amplitudes,” which represent the likelihood that a certain set of particles will turn into certain other particles upon colliding.

....The 60-year-old method for calculating scattering amplitudes — a major innovation at the time — was pioneered by the Nobel Prize-winning physicist Richard Feynman....“The number of Feynman diagrams is so explosively large that even computations of really simple processes weren’t done until the age of computers,” Bourjaily said....In 1986, it became apparent that Feynman’s apparatus was a Rube Goldberg machine....MORE