Old Black Holes May Have a Key to New Life

Via mysteriousuniverse.org by Paul Seaburn

Here comes another example of real life imitating science fiction life. In this case, it’s a recent movie and, fortunately, the movie isn’t Mad Max: Fury Road. A scientist in the Czech Republic proposes a new theory that life can form and possibly thrive on a planet in orbit around a black hole, albeit an old one. Did this idea come to him in the middle of a popcorn bucket consumed during Interstellar?

Tomáš Opatrný is an astrophysicist and faculty member at Palacký University in Olomouc, Czech Republic and yes, the movie Interstellar played a part in his research. Opatrný began by considering a reversal of the second law of thermodynamics (reversing a natural law is never a good thing in life nor in the movies). If life began and thrived on planet Earth in a balance between a hot sun and cold space, why not on a planet between a cold sun (a black hole) and hot space?


Opatrný’s theory requires an old black hole and a tweaking on the definitions of “hot” and “cold.” An old black hole is one that’s no longer consuming everything around it but instead is at a zero temperature except for Hawking radiation, Stephen Hawking’s theoretical black-body radiation that would give black holes a slight non-zero temperature.

When compared to “slightly above absolute zero,” everything else is scorching and that’s the second tweak Opatrný uses. Space is warmed by the residual heat from the Big Bang (cosmic microwave background ) to a temperature of 2.7 kelvin (-270 ˚C). Opatrný says an Earth-sized planet orbiting a black hole about the size of our Sun could get a spark for life from the 900 watts of power generated by the difference between almost absolute zero and nearly almost absolute zero. That’s enough for the survival of some form of life but doesn’t leave much for its evolution (and it’s not much of a movie plot either).

Should doomsday believers start searching for a wormhole and head for the nearest old black hole with Earth-sizes planets? Not so fast, Coop. According to Arizona State University theoretical physicist Lawrence M. Krauss, even old black holes never stop consuming matter and generating energy, so they’ll never get cold enough for a second law of thermodynamics balance with surrounding space. And if it really is doomsday and all of the stars have become black holes (expected to happen a mere 100 trillion years from now), the cosmic microwave background would be gone and there would be no heat to counterbalance with the cold black star.

It’s still an interesting theory. Let’s hope Opatrný keeps going to the movies.

Source