Rinse & Repeat :)

 Olena Shmahalo for Quanta Magazine

Yours truly loves quantum mechanics and the two laws of thermodynamics, at lay level of course, as complexity and operating limits apply to the vagaries of reality including black holes, notions one and all brilliantly described in a wonderful Quanta Magazine article provocatively titled In New Paradox, Black Holes Appear to Evade Heat Death.

To whit ...

Heat death held a morbid fascination for Victorian-era physicists. It was an early example of how everyday physics connects to the grandest themes in cosmology. Drop ice cubes into a glass of water, and you create a situation that is out of equilibrium. The ice melts, the liquid chills, and the system reaches a common temperature. Although motion does not cease — water molecules continue to reshuffle themselves — it loses any sense of progress, and the overall distribution of molecular speeds doesn’t change. 

The 19th-century founders of thermodynamics realized that the same goes for the universe as a whole. Once the stars all burn out, whatever is left — gas, dust, stellar corpses, radiation — will come to equilibrium. “The universe from that time forward would be condemned to a state of eternal rest,” Hermann von Helmholtz wrote in 1854. Modern cosmology has not altered this basic picture.

Unless you look closer as quantum jitters apply in the guise of superposition and entanglement.

When an ice cube melts and attains equilibrium with the liquid, physicists usually say the evolution of the system has ended. But it hasn’t — there is life after heat death. Weird and wonderful things continue to happen at the quantum level. “If you really look into a quantum system, the particle distribution might have equilibrated, and the energy distribution might have equilibrated, but there’s still so much more going on beyond that,” said Xie Chen, a theoretical physicist at the California Institute of Technology.

The black hole at the heart of the M87 galaxy as originally seen in 2017 (left) and after recent data processing by a machine learning algorithm (right).

Medeiros (Institute for Advanced Study), 

D. Psaltis (Georgia Tech), T. Lauer (NSF’s NOIRLab), and F. Ozel (Georgia Tech)

Rinse & Repeat applies :)

Not letting the lack of a rigorous proof stop them, Susskind and Brown suggested in 2018 that the steady growth of complexity qualifies as a new law of nature, the second law of quantum complexity — a quantum analogue of the second law of thermodynamics. The second law of thermodynamics holds that closed systems increase in entropy until they reach thermal equilibrium, the state of maximal entropy. According to Susskind and Brown, the same happens with complexity. A system increases in complexity for eons after it reaches thermal equilibrium. But it does eventually plateau, reaching “complexity equilibrium.” At that point, a quantum system has explored every possible state it is capable of and will finally lose any sense of progress.

The Heisenberg Uncertainty principle to the rescue. :)

We cannot know the exact momentum and position of a particle simultaneously.

Then the system reaches complexity equilibrium, where complexity hits a ceiling. Although the system continues to change, it can no longer be said to evolve — it has no sense of directedness, but wanders among equal states of maximal complexity.

The last stage is called recurrence, where the system stumbles back into its original simple condition. For this to happen by accident is highly improbable. But eternity is a long time, so it ultimately does happen, after a period of time that is not merely exponential, but an exponential of an exponential. The whole process then repeats.

Photo by Linus Mimietz on Unsplash