Astrophysicists: Gamma-ray jets exceed the speed of light
Credit: DESY, Science Communication Lab (used with permission by Astronomy Picture of the Day, which is co-managed by Robert Nemiroff at Michigan Tech).
- Astrophysicists propose that gamma-ray bursts may exceed the speed of light.
- The superluminal jets may also be responsible for time-reversibility.
- The finding doesn’t go against Einstein’s theory because this effect happens in the jet medium not a vacuum.
According to Einstein’s theory of general relativity, nothing can travel faster than the speed of light in a vacuum. Yet in space many strange things happen, including a new proposal by two astrophysicists that blasts creating bursts of gamma rays may be able to speed up faster than light, going superluminal.
Yet, this research by the astrophysicists Jon Hakkila of the College of Charleston and Robert Nemiroff of the Michigan Technological University is not going against Einstein’s theory. What the scientists found is that while these bursts surpass the speed of light in surrounding gas clouds, that only happens in the jet mediums, not in a vacuum.
The astrophysicists also think that these superluminal jets can create the time-reversibility that can be observed in gamma-ray burst light curves.
Jet bursting out of a blazar. Black-hole-powered galaxies called blazars are the most common sources detected by NASA’s Fermi Gamma-ray Space Telescope.
NASA
Jon Hakkila likens what they found to skipping stones across the pond. If someone was to throw such a stone into the water towards you, the stone would go through the air in between hops faster than the waves that it causes are moving through the water. As it gets closer, you will see the waves that are produced by each skip in reverse order. The most recently created ones will get to you first and those from the early skips along the water would come last.
“Standard gamma-ray burst models have neglected time-reversible light curve properties,” Hakkila explained. “Superluminal jet motion accounts for these properties while retaining a great many standard model features.”
Check out the new paper here, published in The Astrophysical Journal.
