Parallel Universes.
The perfect crime tool: Researchers work on ‘event cloak’ By Agence France-PresseMonday, November 15, 2010 22:54 EDT PARIS — Jewelry robbers, magicians, exam cheats and practical jokers everywhere will have an interest in an offbeat idea launched by physicists on Tuesday: to make the passage of time invisible.
The scientists have conceived of a “spacetime cloak” which manipulates light and, in essence, conceals whole events from a viewer. The theory is based on censoring the flow of events, which we perceive as a stream of light particles, also called photons, that strike the retina. Even a Glass of Water Is a Mystery to Physicists. With rendition switcher Question: What are some of the great questions in physics today?
David Albert: Sure. Wave function collapse. When the Copenhagen interpretation was first expressed, Niels Bohr postulated wave function collapse to cut the quantum world from the classical.[5] This tactical move allowed quantum theory to develop without distractions from interpretational worries.
Mathematical description[edit] Mathematical background[edit] The quantum state of a physical system is described by a wave function (in turn – an element of a projective Hilbert space). This can be expressed in Dirac or bra–ket notation as a vector: The kets.