Asked by: Christopher Linden, Poole
Predicted almost a century ago by Einstein, gravitational waves are ripples in the fabric of space and time triggered by massive events like the collision of black holes. Calculations suggest the waves themselves are incredibly feeble, however; as a result, they’re the only major consequence of Einstein’s theory of gravity yet to be directly confirmed. That said, it would be little surprise if Einstein proved right – not least because there’s already indirect evidence for the existence of gravitational waves from studies of massive neutron stars in orbit around each other.
Much more important would be confirmation that current technology really is capable of detecting the incredibly feeble wobbles predicted when gravitational waves pass through the earth – amounting to movements smaller than the diameter of a proton. That would encourage efforts to build super-sensitive detectors able to pick up the waves generated by the birth of our universe – and perhaps, whatever came before.
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