'Perfectly accurate clocks impossible'

The ideal clock is a myth, according to researchers who have shown that in systems with very large accelerations no clock will actually be able to show the real passage of time, known as ''proper time''. Researchers from the University of Warsaw and University of Nottingham showed that in systems moving with enormous accelerations, building a clock that would precisely measure the passage of time is impossible for fundamental reasons.

"In both theories of relativity, special and general, it is tacitly assumed that it is always possible to construct an ideal clock -one that will accurately measure the time elapsed in the system, regardless of whether the system is at rest, moving at a uniform speed, or accelerating," said Andrzej Dragan from the faculty of physics, University of Warsaw. "It turns out, howe ver, that when we talk about really fast accelerations, this postulate simply cannot apply," said Dragan.

If the disturbances affect fundamental clocks such as muons, then any other device built on the principles of quantum field theory will also be disrupted, he said. "Therefore, perfectly precise measurements of proper time are no longer possible," said Dragan.