Resumen de Dark radiation may end cosmic puzzle
If some of the dark matter in the universe is decaying into undetectable radiation, it would solve a niggling mystery about the rate at which our universe is expanding. It would also have major implications for the hunt for dark matter. Cosmologists use precise measurements of the cosmic microwave background (CMB), the radiation left over from the big bang, to calculate the rate at which the universe is expanding, called the Hubble rate. When they compare the rate as calculated based on extrapolating the CMB with the rate given by observing galaxy clusters in the nearby universe, the results are off by about 10 per cent.
