Physicist Sabine Hossenfelder has posted a video about a new paper on arxiv.org, titled “How to Make a Universe” by Paolo Bassani and João Magueijo, which proposes that small random changes to the “constants of nature” (perhaps one should call them parameters rather than constants) – such as the strength of gravity, the strength of the electromagnetic interaction, the masses of particles, and the speed of light – would eventually cause them to reach a settled state of equilibrium where they no longer vary, in pockets of the cosmos. The initial random changes in the constants of nature would allow energy conservation to be violated, and would therefore permit the creation of matter out of nowhere, without needing to appeal to the notion of a hypothetical “inflaton field” (for which there is no experimental evidence). It should be noted that the authors of the paper do not propose that our universe is uniquely optimal. All they are attempting to explain is why the constants of nature aren’t changing now. The authors’ proposal bears some resemblance to Lee Smolin’s hypothesis of “cosmological natural selection”, which postulates that new universes are created inside black holes. The authors make no appeal to black holes in their paper. However, they write (bolding is mine – VJT): “As in biological natural selection, some random mutations produce Universes with matter, others do not, or worse, produce negative energy/matter. One therefore needs the mutation game to be turned off and stability to establish itself to make sure any possible gains are preserved.”

Hossenfelder acknowledges that the authors of the paper still have some explaining to do: “They just assume that the constants can change somehow.” Nevertheless, when commenting on the work of one of the authors (João Magueijo), she adds: “I don’t know if he’s on the right track with this, but still it deserves being taken seriously.”

The authors summarize their conclusions as follows (bolding is mine):

So, in view of all of this: how to make a Universe? Here’s a prescription that complies with some myths and philosophy, as well as the speculations of some respectable physicists, as discussed in the Introduction. Three stages could be distinguished. At each of these stages randomness plays a different role, as discussed in more detail in Section VI. We may summarize them as follows.

• Stage 1: Complete chaos, undefined and incomprehensible. By the nature of the beast, there is no need to “model” anything about this stage or explain how it evolved to the next stage.

• Stage 2: The first structures appear, namely spacetime, a foliation, a metric structure and conceptual separation between matter and gravity. They are described in Secs II-V. Hence concepts such as diffeomorphism invariance, time (in the unimodularlike sense), deterministic time (in)-dependence of the laws, start to make sense; but are not yet realized. Instead, random mutations in the evolution potentials and in the Hamiltonian dominate, as described in Secs. VI-VIII.

• Stage 3: Some of these processes are fortunate enough to evolve to a stage where random evolution stops, deterministic evolution is heavily suppressed (constant β potentials), and the underlying Hamiltonian is nearly diffeomorphism invariant. They correspond to the absorbing state of the Markov higgledy-piggledy chain. They also have matter, created along the chain, to be kept by the Universe from then on.

What do readers think of the new proposal? And if a Divine Being were creating a cosmos containing some life-permitting universes, would it need to follow a similar path? (I’m assuming here that the Creator doesn’t magically “just know” which constants are right for life but has to somehow figure them out, as I can make no sense whatsoever of the notion of someone “just knowing” a fact, without any need for justification.) Over to you.