Kepler Watches White Dwarf Warp Spacetime 58
astroengine writes "The Kepler space telescope's prime objective is to hunt for small worlds orbiting distant stars, but that doesn't mean it's not going to detect some extreme relativistic phenomena along the way. While monitoring a red dwarf star — designated KOI-256 — astronomers detected a dip in starlight in the Kepler data. But it wasn't caused by an exoplanet. After some careful detective work, the researchers found that the red dwarf was actually in orbit around a binary partner — a white dwarf. As the white dwarf passed in front of the red dwarf, the starlight was enhanced by microlensing — a phenomenon caused by an intense gravitational field focusing light from behind. This had the counter-intuitive result of causing the starlight to dim when the white dwarf passed behind the red dwarf and then brighten as the white dwarf passed in front. This is one of the first discoveries of a binary partner through microlensing. 'Only Kepler could detect this tiny, tiny effect,' said Doug Hudgins, Kepler program scientist at NASA Headquarters, Washington. 'But with this detection, we are witnessing Einstein's theory of general relativity at play in a far-flung star system.'"
Re:FTL travel = impossible (Score:5, Informative)
It's entirely true that faster than light travel is forbidden by general relativity. However, geometries with closed timelike curves, which can behave very much like time-machines, are not forbidden. It remains to be seen if such curves can be created and controlled. If they can, then a more complete model would be needed to include the effects of such phenomenon. As it stands, such curves could behave in several ways. In one formulation, self consistency would always be required. In another, such curves could be through another dimension, leading to self-inconsistent histories.
Most importantly, closed timelike curves are sufficiently rare that we have not observed natural occurrences. So, although such possibilites are interesting to consider, they are, ultimately, far beyond our current technologies.
Re:Laws of Physics (Score:5, Informative)
I think that Kepler is looking only at stars in our galaxy, a few hundred or thousand light years away/ago, so the time ago is not that great - within prehistory if not history, We can be pretty confident that laws of physics have not changed much since mammals evolved. This star is apparently 1,828 light years away,
Re:A question for the Astronomers (Score:4, Informative)
So does the doppler method, but I believe there can be a little more difference in the angle, as a doppler shift is slightly easier to measure than a bightness shift, but I am not an expert, I just think I read that somewhere.
Also, IIRC, the astrometry method, which is not very useful requires the solar system to be at about a 90 degree angle in relation to ours.