Gravity Probe B – testing the null hypothesis that the spin axis of a gyroscope will stay aligned with a distant reference point when it’s in a free fall orbit. General relativity says it won’t.
There’s a line out of an early episode of The Big Bang Theory series, where Gravity Probe B is described as having seen ‘glimpses’ of Einstein’s predicted frame-dragging effect. In reality, it is not entirely clear that the experiment was able to definitively distinguish a frame-dragging effect from a background noise created by some exceedingly minor aberrations in its detection system.
Whether or not this counts as a glimpse – frame-dragging (the alleged last untested prediction of general relativity) and Gravity Probe B have become linked in the public consciousness. So here’s a quick primer on what Gravity Probe B may or may not have glimpsed.(…) Read the rest of Astronomy Without A Telescope – Gravity Probe B (703 words)
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(C) Steve Nerlich for Universe Today, 2011. | Permalink | No comment | Add to del.icio.us Post
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