Dark energy may be distorting long-sought gravitational wave signals from distant sources in the universe, according to a paper posted to the arXiv pre-print server by astrophysicists at Penn State University. The waves may still be visible to us, the researchers say, but because of these still poorly understood effects, they could look very different from expected. Blame the expansion of the universe.
By Michael Byrne|MOTHERBOARD
A gravitational wave detection is currently one of astrophysics‘ white whales. Despite an impressive number of detection experiments currently underway worldwide, we’ve yet to actually bag a gravitational wave observation. For the past couple of weeks, the astrophysics rumor mill has been buzzing with the prospect of a detection at the United States‘ massive LIGO experiment—which is based on an interferometer stretching from Washington state to Louisiana—but no announcement has been made, nor does one seem to be forthcoming.
The difficulty in detecting gravitational waves has to do with their relative weakness. They arise as the result of some massive body, with a very large amount of gravitational attractiveness, accelerating through space and leaving faint ripples in the fabric of space-time. This is general relativity: gravity deforms space-time itself. An acceleration, a change in velocity, will cause a change in this deformation, which we should be able to experience as gravitational waves.