Penrose interpretation

From Wikipedia, the free encyclopedia

This article or section is in need of attention from an expert on the subject.
Please help recruit one or improve this article yourself. See the talk page for details.
Please consider using {{Expert-subject}} to associate this request with a WikiProject

The Penrose interpretation is an interpretation of quantum mechanics formulated by Sir Roger Penrose. This theory is a possible step toward Quantum gravity, as it describes quantum mechanics in terms of General relativity. It states that a system requires energy to allow it to exist in more than one location. A macroscopic system, such as a human, cannot exist in more than one position because its significant gravitational field requires it to have a large amount of energy to sustain, and will settle into one position within a trilionth of a second. However a microscopic system or particle (such as an electron) has an insignificant gravitational field, and therefore requires so little energy that it could exist in more than one location almost indefinitely; This is called superposition.

In Einstein's theory, any object that has mass causes a warp in the structure of space and time around it. This warping produces the effect we experience as gravity. Penrose points out that tiny objects, such as dust specks, atoms and electrons, produce space-time warps as well. Ignoring these warps is where most physicists go awry. If a dust speck is in two locations at the same time, each one should create its own distortions in space-time, yielding two superposed gravitational fields. According to Penrose's theory, it takes energy to sustain these dual fields. The stability of a system depends on the amount of energy involved: the higher the energy required to sustain a system, the less stable it is. Over time, an unstable system tends to settle back to its simplest, lowest-energy state: in this case, one object in one location producing one gravitational field. If Penrose is right, gravity yanks objects back into a single location, without any need to invoke observers or parallel universes.

Penrose hypothesised that the transition between macroscopic and quantum begins on the scale of dust particles, which could exist in more than one location for as long as one second (a very long time compared with that of larger objects). An experiment has been developed to test this theory, in which an X-ray laser in space is directed toward a tiny mirror, and fissioned by a beam splitter from thousands of miles away, with which the photons are directed toward other mirrors and reflected back. One photon will strike the tiny mirror moving en route to another mirror and move the tiny mirror back as it returns, and according to some interpretations of quantum mechanics, that the tiny mirror exists in two locations at one time. If gravity affects the mirror, it will be unable to exist in two locations at once because gravity holds it in place.

However, because this experiment would be difficult to set up, a table-top version has been proposed instead.