Guest blog by Liam McAllister, Cornell University.The BICEP2 team has just announced a remarkable discovery (FAQ): they argue that they have detected, at very high significance, the imprint of primordial gravitational waves on the polarization of the cosmic microwave background. Moreover, the signal they see is very strong. If they are right, this is The Big One.
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| BICEP on site at the South Pole |
BICEP's map of the CMB:
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| Vorticity in the CMB according to BICEP |
How should we interpret this result, and what are its implications?
If the BICEP measurement really is a detection of primordial gravitational waves, and if we interpret this finding in the context of the overwhelmingly favored theory for producing primordial gravitational waves — namely, inflation — then the implications of this finding are staggering. I find it hard to imagine a more powerful, more transformative experimental result anywhere in fundamental physics, short of a discovery of extra dimensions or of a violation of quantum mechanics.
Let me now temper this excitement with a number of cautionary remarks, and then explain why a detection of inflationary gravitational waves would be so important.
