Lee Smolin is an astrophysicist who studied string theory and moved on to explore other avenues, such as loop quantum gravity, of reaching a unified field theory. A unifying field theory is the holy grail of physics. It’s where the theory of relativity and quantum mechanics no longer conflicts and the mathematics perfectly intertwine.
Thus far the answer has eluded us, and the most favored branch of science working to solve the problem is String Theory. Proponents of loop quantum gravity and String Theory often clash, as the below video excerpt will invariably show:
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Does The Concept Of Natural Selection Expand Beyond The Boundaries Of Biology?
This article will offer you zero insight as to which of these theories is more promising. What it will do however is to explore, what to my mind, is Lee Smolin’s most elegant and interesting theory called Cosmological Natural Selection. The theory surmises that a collapsing black hole gives birth to a new Universe on the other side. These inflating Universes would have similar, but not have precisely the same fundamental constants of physics as their parent Universe. What follows is natural selection on the cosmological scale bearing a strong resemblance of how natural selection operates on the biological scale.
When Stars Collapse
It stands to reason, within the context of Lee Smolin’s theory, that black holes are absolutely necessary for a Universe to give birth to others. Black holes form when a massive star, over ten solar masses – a solar mass being equivalent to the mass of our own Sun – reaches the end of its lifespan.
Nuclear chain reactions at the core of a star keeps it relatively stable and burning brightly, but eventually the fuel to continue these reactions is exhausted and the star dies. If the star is massive enough the iron at its core will cause the star to collapse in on itself to form a black hole. Particularly colossal stars can turn into a super novae, which can still result in a black hole, and are one of the most spectacularly powerful of events that occur in our cosmos.
We Are Made of Stardust: A Meaningless Platitude Or An Inescapable Truth?
In the core of a star elements are fused together from the nuclear reactions and extreme heat and pressure. When Iron is fused it does not release energy and does not fuse into heavier elements, but remains iron, and hence it builds up over time within the core of the star. This is a minor tangent, but when you hear the phrase, ‘we’re made of star stuff’, it’s literally true, and it’s thanks to the super novae.
The mind bending explosion is hot enough to create the rarer elements and spreads them across galaxies in gas clouds that, thanks to gravity, eventually condense into planets. Another common phrase that perhaps isn’t appreciated enough is ‘stars die so people can live’, though one could doubt there was any intent involved on the part of the star.
A Black Hole: The Womb Of A Parent Universe ?
Once we have stars gravity takes over to eventually assemble galaxies. Once we have galaxies, the potential for what we currently comprehend as life exists. This demonstrates that the same cosmological constants necessary for stars, and eventually life to form, are the same cosmological constants that are required for black holes to form.
Universes where the physical laws don’t allow for massive enough stars to form are then impotent to produce offspring Universes with similar properties. In turn, the Universes that have the right physical properties for abundant black holes are more likely to spawn other flourishing Universes. If this is the case, we should not be surprised to find ourselves living in so finely tuned a Universe as to allow humans to evolve and to observe it.
The Anthropic Principle
Theists will argue the physical parameters of our Universe are so fine tuned that there’s no other explanation than an all powerful being having created it. In a Multiverse – be it Lee Smolin’s Theory or String Theory, the anthropic principle handles this problem. Simply put, even if the parameters of physics existing in a Universe to allow for the formation of stars, galaxies and life were extraordinarily rare, with seemingly endless Universes, those few with the necessary parameters would be, by definition, the only capable of being observed by life that evolved within it. Lee Smolin’s theory has the added elegance of evolving Universes in a fashion as to make it ever more increasingly probable that future generations of Universes will also be able to support life. This is not the most popular cosmological theory in play, and some insist that String Theory is the only game in town as far as a unified theory of everything is concerned, but it is a beautifully elegant hypothesis that’s worth being aware of.
I think it would be fair to let Lee Smolin weigh in on the subject, with it being his theory and all.
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