In The Self-Organizing Recursive Cosmos, I discussed Lee Smolin's cosmological natural selection hypothesis presented in his book the Life of the Cosmos.
Life of the Cosmos (1997)
https://tkececi.files.wordpress.com/2009/12/the-life-of-the-cosmos.pdf
Lee Smolin's cosmological natural selection hypothesis attempts to explain why our very complex Universe is the way it is in terms of the Darwinian mechanisms of inheritance and innovation honed by natural selection. His hypothesis is a cosmic example of Universal Darwinism at work at a cosmological level and is certainly in tune with the propositions presented in The Law of Increasing Functional Information and the Evolution of Software. But in this post, I would like to extend Lee Smolin's cosmological natural selection hypothesis to include some work by J. Ambjørn and Y. Watabiki as presented in Anton Petrov's YouTube:
Study Explains Dark Energy and Inflation as Parallel Universes Colliding
https://www.youtube.com/watch?v=qg4PZst9a5g
and their recent paper:
Is the present acceleration of the Universe caused by merging with other universes?
https://iopscience.iop.org/article/10.1088/1475-7516/2023/12/011/pdf
The hypothesis that J. Ambjørn and Y. Watabiki present in the above paper is that the highly-varying expansion rate of our Universe since the Big Bang can be mathematically explained by collisions of baby Universes with more mature Universes.
Figure 1 - The expansion rate of our Universe has varied greatly over the past 13.7 billion years. For example, just after the Big Bang, our Universe went through a period of Inflation that expanded the Universe by a factor of 1026 in 10-32 seconds! It then continued to expand at a slowing rate for about 9 billion years. Then about 5 billion years ago, the expansion rate began to increase. In the above figure, this varying rate of expansion is displayed in the curvature of the envelope surrounding our Universe. Notice the dramatic expansion of the envelope during Inflation and that after 9 billion years of expansion, the envelope is now bending upwards as the expansion rate accelerates. Click to enlarge.
Currently, nobody knows why the expansion rate of our Universe has varied in such a dramatic fashion. We do not know what caused the dramatic Inflation that expanded the Universe by a factor of 1026 in 10-32 seconds or why our Universe is now expanding at a faster rate than it did 5 billion years ago. Up until 1998, cosmologists expected the expansion rate to be slowing down instead of speeding up. Some propose that 75% of our Universe is composed of a dark energy that is driving the acceleration of the expansion rate while others point to a time-varying cosmological constant in Einstein's general relativity. J. Ambjørn and Y. Watabiki propose that both of these problems can be explained by the collision of baby bubble universes colliding with more mature and larger bubble universes. But before doing that, let's review Lee Smolin's cosmological natural selection hypothesis that I discussed in
The Self-Organizing Recursive Cosmos.
Lee Smolin's cosmological natural selection hypothesis
Lee Smolin wonders why our Standard Model of particle physics is so complicated with so many "fundamental" particles arising from excited quantum fields.
Figure 2 – The Standard Model of particle physics is composed of quantum fields that we observe as particles. The matter particles are called fermions and have a spin of ½. The force-carrying particles are called bosons and they have a spin of 1. The Higgs boson has a spin of 0 and is a scalar field.
If you count the antimatter particles, the Standard Model contains 12 quarks and 12 leptons. But each of the 12 quarks comes in one of three color charges - red, green or blue. That means there really are 36 different quarks. There are also really 8 gluons because gluons have a combination of two color charges (one of red, green, or blue and one of antired, antigreen, or antiblue). So that comes to 36 quarks + 12 leptons + 13 bosons = 61 particles!
Many other physicists are also perplexed by the complexities of the Standard Model too. There just seem to be way too many fundamental particles and forces. Many physicists would like to replace our current Standard Model with a new more fundamental model that does not have so many moving parts such as string theory.
Figure 3 – Early in the 20th century, physicists were also perplexed by the very numerous fundamental elements of the Periodic Table. But atom smashers soon revealed that this very large number of fundamental elements were all simply composed of three particles - protons, neutrons and electrons. Perhaps the same could be said of the numerous particles of the Standard Model.
But Lee Smolin suggests that there might be another explanation for the complexity of our current Standard Model. Perhaps our current Standard Model is the "real deal" and its complications are the result of a long evolutionary history.
Figure 4 – Above is a simplified flowchart of the metabolic pathways used by carbon-based life. Notice that it too is a fine-tuned mess that seems to work nonetheless. However, in this case, we do know that carbon-based life actually is a fine-tuned mess that works superbly despite all of its complexity. Biologists had to come up with some mechanism to explain how such a fine-tuned mess came to be and they finally did so with Darwinian thought.
Living things are incredible examples of highly improbable fine-tuned systems, and this fine-tuning was accomplished via the Darwinian mechanisms of inheritance and innovation honed by natural selection. Along these lines, Lee Smolin proposes that when black holes collapse they produce a white hole in another universe, and the white hole is observed in the new universe as a Big Bang. He also proposes that the physics in the new universe would essentially be the same as the physics in the parent universe, but with the possibility for slight variations to arise when a black hole reaches the Planck density. In this view, the seemingly fixed and immutable laws and constants of our Universe are no more so than the fixed and immutable species of a pre-Darwinian biosphere. For Lee Smolin, a universe that had the physics that was good at creating black holes would tend to outproduce universes that did not. Thus, a selection pressure would arise that selected for universes that had a physics that was good at making black holes, and so, a kind of Darwinian natural selection would occur in the Cosmic Landscape of the Multiverse. Over an infinite amount of time, the universes that were good at making black holes would be found to dominate the Cosmic Landscape. He calls this effect cosmological natural selection.
Figure 5 - In Lee Smolin's the Life of the Cosmos he proposes that the black holes of one universe puncture the spacetime of the universe, causing white holes to appear in new universes.
Figure 6 – As the white holes expand.
Figure 7 – They eventually pinch off to form new baby Universes.
Figure 8 – Forming an eternal Multiverse of bubble Universes of varying ages and sizes that self-replicate like a never-ending recursive function in a program that keeps calling itself over and over.
In their paper, J. Ambjørn and Y. Watabiki propose that the dramatic expansion of our Universe after the Big Bang during the very brief Inflation period resulted when our baby Universe bubble collided with a much larger and older Universe bubble. This collision splattered our baby Universe bubble over the surface of a much larger bubble Universe like a bug hitting the windshield of a much larger car. Our bubble Universe then continued to expand much more slowly as the bubble Universe that we had just joined continued to expand. The expansion of this much larger bubble universe was further driven by the absorption of a huge number of other baby bubble universes that it continued to scoop up.
Figure 9 – As a bubble universe collides with other bubble universes it continues to expand. The expansion rate is determined by the rate of absorption of other bubble universes.
Figure 10 – The end result is an eternal Multiverse that has always existed and is composed of an infinite number of bubble universes of varying ages and sizes.
Now according to the cosmological natural selection hypothesis, each bubble universe inherits the physics of its parent universe but also with the possibility of some slight mutations. In this new model, perhaps only bubble universes with the same or very similar physics can merge. If that were the case perhaps our bubble Universe looks more like a sample of granite formed from rock-forming silicate minerals.
Figure 11 – When granitic magma cools it forms granite composed of silicate minerals formed from silica tetrahedrons with a net charge of -4 mixed with various amounts of positive K+, Na+, Ca++, Mg++, Fe++, Al+++ and Fe+++ cations in rock-forming minerals.
Figure 12 – There are many ways to chain silica tetrahedrons together to form rock-forming minerals. They can form chains, double chains, sheets and 3D-networks. The grains of silica sand are composed of the mineral quartz which is a very tough 3D-network of pure silica tetrahedrons. Other silicate minerals mix in positive cations amongst the silica tetrahedrons to neutralize the negative charge of the silica tetrahedrons.
As you move through the granitic matrix of a granite rock sample, the mineral chemistries vary slightly, but the rock still holds together. Perhaps bubble Universes might have a similar texture of crystals of similar but varying physics. Our universe could then be deeply buried in one of these crystals. We would never be able to see any of the other grains of our bubble universe because they would all be far beyond our Hubble radius.
Figure 13 – The "Observable Universe" is now about 46 billion light years away from us. But the current Hubble radius is now only about 13.7 - 14.5 billion light years away. The current Hubble radius is where spacetime is currently expanding away from us faster than the speed of light. So the Hubble radius is the furthest distance that we could now reach traveling at the speed of light and the light from objects beyond the current Hubble radius will never reach us.
So, like all of the other hypotheses that attempt to explain the evolutionary history of the expansion of our Universe, this new model also lacks observed confirmational data. The best that we may be able to do is to create hypotheses that explain all of our current observations, do not contradict themselves and do not contradict the known physics of the day. But if this new model is somewhat true, then we may be faced with trying to unravel the details of a bug splattered on a windshield.
Figure 14 - The cosmic microwave background may be all that is left of a bug splattered on a windshield.
Comments are welcome at
scj333@sbcglobal.net
To see all posts on softwarephysics in reverse order go to:
https://softwarephysics.blogspot.com/
Regards,
Steve Johnston
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