Universe Self-Replication Cosmology - a compelling option that doesn't get the attention it deserves

 

This drawing is from Alan Guth, MIT Dept. of Physics.
It is what physicists call an 'embedding diagram'.  It represents three-dimensional space as a two-dimensional surface that is 'bent' or curved by gravity.  This diagram depicts one of the basic ways that an existing universe (e.g., the one we live in) can generate, via quantum tunneling, an entirely new and separate child universe.

Currently known and accepted laws of physics appear to allow this -- a quantum 'phase change' of a small 'seed' of matter (just a few grams) into a peculiar state called a 'false vacuum' or something like it, which has negative pressure, and can therefore expand into a whole universe at an astounding rate.

 The diagram depicts the moment that the 'umbilical cord' (wormhole or Ellis Drainhole) connecting the parent and child universe snaps, and the child universe becomes a completely separate new universe.
See Farhi, Guth, and Guven (Nuclear Physics B, Volume 339, Issue 2, 30 July 1990, Pages 417-490) for all the detail.

(last updated 30 Nov 2024)

This post is devoted to the simple, hard, physical argument of whether and how a universe with the physical laws that ours has can self-replicate, the three main ways this can occur based on the known laws, and the far-reaching consequences that seem to inevitably result.

Question 1:  Can a universe with the physical laws that our universe has self-replicate?

Answer:  We have no experimental evidence that this has happened, but also no evidence that it is impossible.  Not only do the laws of physics as we currently understand them seem to allow it, but there seem to be at least three different ways that it can happen.  In at least in two of these ways, an experiment can be performed that could confirm it.

Question 2:  What are the three ways that our currently accepted physical laws permit this to happen?

First way:  a natural, spontaneous quantum tunneling.  It seems to require very high density and high energy, perhaps to levels only found in black holes.  Lee Smolin has discussed the black hole option in his Cosmological Natural Selection theory, which, unfortunately has been latched-onto by a lot of crackpot web sites.  (Please note that my own post, Firestorm in the Universe, is of that ilk, being full of speculation and unbridled enthusiasm without sufficient logical or scientific constraint.  But also, please note that I am a PhD research Atmospheric Scientist who worked for NASA for 25 years.)  The discussion in this post is intended to scrupulously stick with what can be confirmed via theoretical calculations that are also falsifiable and potentially testable by experiment.  Details of the current status of Smolin's theory will be presented later in this post.  In general, there is no theoretical prohibition for such a quantum tunneling event to take place in 'normal' space, i.e., not beyond the event horizon of a black hole.  It may be such an extremely low-probability event that no currently practical experiment could ever hope to detect it, however theoretically, by the laws of quantum physics, anything that is possible is inevitable.  Again, further discussion will follow as this post is developed.

Second way:  Production of child universes in a laboratory or Particle Collider.  This is the scenario discussed in the 1990 Nuclear Physics B article mentioned in the caption to the introductory image at the top of this post.

Third way:  Simulation.  Current computer power allows scientists to simulate selected physical systems in great detail, but such calculations fall far short of being capable of simulating processes in sufficient detail to address some of the fundamental questions that we do not yet have answers to, such as how life emerged and how self-aware 'intelligent' beings emerged.  But there does not seem to be any obstacle that would prevent us from someday being capable of answering such deep questions via simulation.  If future technology makes such robust simulations possible, and because our known universe contains only a finite amount of information, there is no known physical or philosophical reason to expect that we could not someday create a simulated subset of our universe that could pass any pre-established arbitrarily test of 'adequacy'.  The first such simulation is likely to focus on an individual 'AI being' that will surpass human intelligence and will profess to be conscious, and this may not be more than a few years or decades away.

Question 3:  What are the consequences if universes like ours can self-replicate?

Answer:  Analysis of the potential consequences of this cosmology have been sparse.  Three of these consequences are of particular note:

First:  Our universe came from a 'preceding' parent universe.  If self-replication is occurring, then it is nearly certain that it is the explanation of the origin of the particular universe that we observe.  Our universe, with all its complexity, was not original - not cut from whole cloth, so to speak.

Second:  The 'Fine Tuning' question: In the cases where self-replication occurs in the 'open' universe, i.e., not inside the event horizon of a black hole, and particularly in any of the set of scenarios where intelligent beings (or even simple forms of life) are present to interact with or direct the replication process, there is a potential for the laws of physics in the offspring universes to be skewed favorably toward the living forms involved.  This could provide a natural explanation of what has been called the 'Fine Tuned Universe' conjecture or hypothesis or question, which asks why or how our universe seems to be so well-suited for the development of life, when such an outcome is estimated (by the majority of physicists) to have a prohibitively low probability within the range of possible sets of governing laws and constants.

Third:  Evolutionary processes, analogous to those that pertain to the development of complex life forms from simple ones, if operative during universe self-replication, would push back the difficult question of the ultimate origin of reality (e.g., the mechanism or process that produced the "Big Bang") into a veil of obscurity that might be as difficult to unravel as the question of abiogenesis--the means by which life emerged from the approximately 92 natural elements of the Periodic Table, as generated by cosmic and/or stellar nucleosynthesis.