Big Rip

In physical cosmology, the Big Rip is a hypothetical cosmological model concerning the ultimate fate of the universe, in which the matter of the universe, from stars and galaxies to atoms and subatomic particles, is progressively torn apart by the gravitational influence of dark energy at a certain time in the future, such that distances between particles infinitely increase. According to the standard model of cosmology, the scale factor of the universe is accelerating, and, in the future era of cosmological constant dominance, will increase exponentially. But this expansion is similar for every moment of time (hence the exponential law—the expansion of a local volume is the same number of times over the same time interval), and is characterized by an unchanging, small Hubble constant, effectively ignored by any bound material structures. By contrast, in the Big Rip scenario the Hubble constant increases to infinity in a finite time. According to recent studies, the universe is set for a constant expansion and heat death, because the equation of state parameter w = −1. The Big Rip is only possible if the universe contains phantom energy, a hypothetical form of dark energy with implausible physical properties.