gravitational waves

Our physics color commentator Rob Sheldon has this to say: — I’ve been a skeptic of the gravity wave observations from the very beginning. The noise is ONE MILLION times stronger than the signal, which in every other field of science, pretty much excludes the opportunity of seeing the signal. Making this worse, no one knows what the signal looked like, having never seen a gravity wave before. At best, we make models of what we think it might look like, but how can one be sure? Finally and perhaps the killer, LIGO’s method of signal extraction is borrowed from RADAR analysis, where “matched filters” are used. Only radar engineers actually know what the signal looks like since they sent it, Read More ›

The 2015 find may have been an illusion: The Laser Interferometer Gravitational-Wave Observatory collaboration, better known as LIGO, switched on its upgraded detectors on 12 September 2015. Within 48 hours, it had made its first detection. It took a few months before the researchers were confident enough in the signal to announce a discovery. Headlines around the world soon heralded one of the greatest scientific breakthroughs of the past century. In 2017, a Nobel prize followed. Five other waves have since been spotted. Or have they? That’s the question asked by a group of physicists who have done their own analysis of the data. “We believe that LIGO has failed to make a convincing case for the detection of any Read More ›

Not if you go by results from the gravitational waves collision. While last year’s discovery of gravitational waves from colliding neutron stars was earth-shaking, it won’t add extra dimensions to our understanding of the universe—not literal ones, at least. University of Chicago astronomers found no evidence for extra spatial dimensions to the universe based on the gravitational wave data. Their research, published in the Journal of Cosmology and Astroparticle Physics, is one of many papers in the wake of the extraordinary announcement last year that LIGO had detected a neutron star collision. It appears for now that the universe has the same familiar dimensions—three in space and one of time—even on scales of a hundred million light-years. But this is Read More ›

From John Timmer at Ars Technica: LIGO’s detection of gravitational waves came almost exactly a century after Einstein had formulated his general theory of relativity and an ensuing paper mathematically describing the possibility of gravitational waves. Or at least that’s the story as it was presented to the public (including by yours truly). And in some ways, it’s even true. But the reality of how relativity progressed to the point where people accepted that gravitational waves are likely to exist and could possibly be detected is considerably more complicated than the simple narrative described above. In this week’s Nature Astronomy, a group of science historians lays out the full details of how we got from the dawn of relativity to Read More ›