https://aeon.co/essays/why-is-simplicity...xplanation
EXCERPTS (Johnjoe McFadden): . . . Simple scientific laws are preferred, then, because, if they fit or fully explain the data, they’re more likely to be the source of it. With more knobs to tweak, arbitrarily complex models such as Ptolemy’s astronomical system could be made to fit any dataset. As the mathematician John von Neumann once quipped: ‘with four parameters I can fit an elephant, and with five I can make him wiggle his trunk’.
Is there more to simplicity than probability? Many of the greatest scientists and philosophers were devotees of what might be called a strong version of Occam’s Razor. This claims that the world is about as simple as it can be, consistent with our existence. The theoretical physicist and Nobel Laureate Eugene Wigner’s influential paper ‘The Unreasonable Effectiveness of Mathematics in the Natural Sciences’ (1960) argued that the extraordinary ability of mathematics to make sense of the world is a puzzle. An analogous case can be made for the success of simplicity in science. Why is Occam’s Razor so unreasonably effective? Why does simplicity work so well?
[...] But could it be simpler still? Why are there 17 particles in the Standard Model of particle physics when we are composed of only a handful? If the Universe is maximally simple, why are trillions of almost massless and electrically neutral neutrinos passing through our bodies every second? Surely neutrinos are entities beyond our necessity? Another candidate for an entity beyond necessity is the mysterious dark matter, of which our Universe appears to be chiefly composed. Why does a simple universe harbour so much apparently superfluous stuff?
In fact, both dark matter and neutrinos are essential for our existence. Neutrinos are a necessary byproduct of the stellar nuclear-fusion reactions that fuse protons to make helium nuclei, plus the heat and light that make life possible. One of physics’ laws of conservation demands that the total number of leptons (electrons, muons, tau particles and neutrinos) must remain constant. This can be satisfied in the stellar fusion reaction only through the release of massive numbers of neutrinos. Similarly for dark matter. In the early Universe, it acted as a kind of cosmological clotting agent that helped to coalesce the diffuse gas that emerged from the Big Bang into the lumpy clouds that became galaxies, stars, planets and eventually us. Haloes of dark matter at the edge of galaxies also act as galactic guardians, deflecting high-speed supernovae remnants rich in the heavy elements essential for life, from shooting off into the vast empty reaches of intergalactic space.
In my latest book, I propose a radical, if speculative, solution for why the Universe might in fact be as simple as it’s possible to be. Its starting point is the remarkable theory of cosmological natural selection (CNS) proposed by the physicist Lee Smolin. CNS proposes that, just like living creatures, universes have evolved through a cosmological process, analogous to natural selection.
[...] Smolin came up with CNS as a potential solution to what’s called the fine-tuning problem: how the fundamental constants and parameters, such as the masses of the fundamental particles or the charge of an electron, got to be the precise values needed for the creation of matter, stars, planets and life. ... our region of the Universe is filled with an estimated 100 billion supermassive black holes, Smolin proposes that each is the progenitor of one of 100 billion universes that have descended from our own.
The model Smolin proposed includes a kind of universal self-replication process, with black holes acting as reproductive cells. The next ingredient is heredity. Smolin proposes that each offspring universe inherits almost the same fundamental constants of its parent. The ‘almost’ is there because Smolin suggests that, in a process analogous to mutation, their values are tweaked as they pass through a black hole, so baby universes become slightly different from their parent. Lastly, he imagines a kind of cosmological ecosystem in which universes compete for matter and energy. Gradually, over a great many cosmological generations, the multiverse of universes would become dominated by the fittest and most fecund universes, through their possession of those rare values of the fundamental constants that maximise black holes, and thereby generate the maximum number of descendant universes.
Smolin’s CNS theory explains why our Universe is finely tuned to make many black holes, but it does not account for why it is simple. I have my own explanation of this, though Smolin himself is not convinced. First, I point out that natural selection carries its own Occam’s Razor that removes redundant biological features through the inevitability of mutations. [...] Perhaps a similar process of purifying selection operates in cosmological natural selection to keep things simple. Instead of biological mutations, we have tweaks to fundamental constants of universes as they pass through black holes.
[...] Universes will compete for available resources – matter and energy – and the simplest that convert more of their mass into black holes will leave the most descendants. For both scenarios, if we ask which universe we are most likely to inhabit, it will be the simplest, as they are the most abundant. When inhabitants of these universes peer into the heavens to discover their cosmic microwave background and perceive its incredible smoothness, they, like Turok, will remain baffled at how their universe has managed to do so much from such a ‘stunningly simple’ beginning.
The cosmological razor idea has one further startling implication. It suggests that the fundamental law of the Universe is not quantum mechanics, or general relativity or even the laws of mathematics. It is the law of natural selection discovered by Darwin and Wallace. As the philosopher Daniel Dennett insisted, it is ‘The single best idea anyone has ever had.’ It might also be the simplest idea that any universe has ever had... (MORE - missing details)
EXCERPTS (Johnjoe McFadden): . . . Simple scientific laws are preferred, then, because, if they fit or fully explain the data, they’re more likely to be the source of it. With more knobs to tweak, arbitrarily complex models such as Ptolemy’s astronomical system could be made to fit any dataset. As the mathematician John von Neumann once quipped: ‘with four parameters I can fit an elephant, and with five I can make him wiggle his trunk’.
Is there more to simplicity than probability? Many of the greatest scientists and philosophers were devotees of what might be called a strong version of Occam’s Razor. This claims that the world is about as simple as it can be, consistent with our existence. The theoretical physicist and Nobel Laureate Eugene Wigner’s influential paper ‘The Unreasonable Effectiveness of Mathematics in the Natural Sciences’ (1960) argued that the extraordinary ability of mathematics to make sense of the world is a puzzle. An analogous case can be made for the success of simplicity in science. Why is Occam’s Razor so unreasonably effective? Why does simplicity work so well?
[...] But could it be simpler still? Why are there 17 particles in the Standard Model of particle physics when we are composed of only a handful? If the Universe is maximally simple, why are trillions of almost massless and electrically neutral neutrinos passing through our bodies every second? Surely neutrinos are entities beyond our necessity? Another candidate for an entity beyond necessity is the mysterious dark matter, of which our Universe appears to be chiefly composed. Why does a simple universe harbour so much apparently superfluous stuff?
In fact, both dark matter and neutrinos are essential for our existence. Neutrinos are a necessary byproduct of the stellar nuclear-fusion reactions that fuse protons to make helium nuclei, plus the heat and light that make life possible. One of physics’ laws of conservation demands that the total number of leptons (electrons, muons, tau particles and neutrinos) must remain constant. This can be satisfied in the stellar fusion reaction only through the release of massive numbers of neutrinos. Similarly for dark matter. In the early Universe, it acted as a kind of cosmological clotting agent that helped to coalesce the diffuse gas that emerged from the Big Bang into the lumpy clouds that became galaxies, stars, planets and eventually us. Haloes of dark matter at the edge of galaxies also act as galactic guardians, deflecting high-speed supernovae remnants rich in the heavy elements essential for life, from shooting off into the vast empty reaches of intergalactic space.
In my latest book, I propose a radical, if speculative, solution for why the Universe might in fact be as simple as it’s possible to be. Its starting point is the remarkable theory of cosmological natural selection (CNS) proposed by the physicist Lee Smolin. CNS proposes that, just like living creatures, universes have evolved through a cosmological process, analogous to natural selection.
[...] Smolin came up with CNS as a potential solution to what’s called the fine-tuning problem: how the fundamental constants and parameters, such as the masses of the fundamental particles or the charge of an electron, got to be the precise values needed for the creation of matter, stars, planets and life. ... our region of the Universe is filled with an estimated 100 billion supermassive black holes, Smolin proposes that each is the progenitor of one of 100 billion universes that have descended from our own.
The model Smolin proposed includes a kind of universal self-replication process, with black holes acting as reproductive cells. The next ingredient is heredity. Smolin proposes that each offspring universe inherits almost the same fundamental constants of its parent. The ‘almost’ is there because Smolin suggests that, in a process analogous to mutation, their values are tweaked as they pass through a black hole, so baby universes become slightly different from their parent. Lastly, he imagines a kind of cosmological ecosystem in which universes compete for matter and energy. Gradually, over a great many cosmological generations, the multiverse of universes would become dominated by the fittest and most fecund universes, through their possession of those rare values of the fundamental constants that maximise black holes, and thereby generate the maximum number of descendant universes.
Smolin’s CNS theory explains why our Universe is finely tuned to make many black holes, but it does not account for why it is simple. I have my own explanation of this, though Smolin himself is not convinced. First, I point out that natural selection carries its own Occam’s Razor that removes redundant biological features through the inevitability of mutations. [...] Perhaps a similar process of purifying selection operates in cosmological natural selection to keep things simple. Instead of biological mutations, we have tweaks to fundamental constants of universes as they pass through black holes.
[...] Universes will compete for available resources – matter and energy – and the simplest that convert more of their mass into black holes will leave the most descendants. For both scenarios, if we ask which universe we are most likely to inhabit, it will be the simplest, as they are the most abundant. When inhabitants of these universes peer into the heavens to discover their cosmic microwave background and perceive its incredible smoothness, they, like Turok, will remain baffled at how their universe has managed to do so much from such a ‘stunningly simple’ beginning.
The cosmological razor idea has one further startling implication. It suggests that the fundamental law of the Universe is not quantum mechanics, or general relativity or even the laws of mathematics. It is the law of natural selection discovered by Darwin and Wallace. As the philosopher Daniel Dennett insisted, it is ‘The single best idea anyone has ever had.’ It might also be the simplest idea that any universe has ever had... (MORE - missing details)