PHYSICS is often a waiting game. Exploring the deepest foundations of reality is rarely straightforward. Take tests of relativity, for example. Gravity Probe B, which is due to deliver its initial results on relativity later this year, took 40 years to launch into space.
And LIGO, the Laser Interferometer Gravitational-Wave Observatory, begun in the early 1970s is only operational now. Even so it is unlikely to see any gravity waves, from the birth of a black hole for example, without an upgrade that is not due until 2010. In fact, we probably will not be certain about the existence of…
