by STUART KAUFFMAN
A note: By accident, the present post should have been posted last week, and last week's post should have been posted today. It may be useful to read the present post, and then, should you wish, read last week's post and my comments there for increased, I hope, clarity. — S. Kauffman
The universe is vastly complex. In my previous blog I pointed out that the fine tuning of the 23 constants of nature in the Standard Model and General Relativity were, perhaps, a necessary, but not a sufficient condition for our universe to have become complex.
We have no adequate theory for why our universe is complex. Indeed, I will say that we can have no such complete theory. But we can link fragments that may grow in time to a more integrated web of theory and observation.
To begin at the beginning, assuming the Big Bang. The universe started extremely hot, dense, and essentially uniform, or isotropic. Perhaps all four forces, Electro-Magnetic, Weak, Strong and Gravity really were united into a single unified force. A first essential to a complex universe is that it expanded and cooled. By cooling symmetries can be broken. Probably the first ones to be broken were those separating the four forces. If we accept Inflation in the very early universe, exponentially rapid expansion of early space solves the problem of why regions out of causal contact with one another due to the finite speed of light, and causal contact, are essentially uniform - the famous Horizon problem. Quantum fluctuations just before that Inflation are believed to lead to the 1/10,000 inhomogenieties in mass density that later congeled into first generation stars and galaxies that outlive their stars. Supernovae in some stars, and the nuclear reactions from hydrogen to all the heavier elements created the atomic distribution of atomic species in the universe.
Eric Chaisson’s Cosmic Evolution is a wonderful discussion of these processes. And in the last blog I noted his view, well supported, that the energy density per gram universe per second has increased over the course of cosmic, biological and cultural evolution. Energy per unit time is a “power”, so the power density per gram universe has gone up. A deep issue is how can this have happened? What would be a prototheory to account for this?
At present, I can only glimmer fragments. I hope they will build, either in these blogs or beyond, usefully.
I begin with the precient, brilliant insight of Schrodinger in “What is Life”, 1944, and before Shannon and Kolmogorov begat Information theory. Neither Shannon nor Kolmogorov tell us what information IS, only how much of it we have, where information came from in the evolution of the universe, nor what the semantics of that information is. All this disembodied information appears deeply mysterious, along with matter and energy. I think Shannon and Kolmogorov, brilliant, boarded the wrong boat.
Schrodinger wondered at the stability of life and the character of the gene. It had to be based on quantum mechanics, for the statistics of ink diffusing in a petri plate would not account for the heritable stability of life. So genes must be “solids”. Then Schrodinger lept: The gene would not be a “periodic crystal”. “Too dull”, is all he says. “Rather, the gene will be an “aperiodic crystal that contains a microcode for the organism.” How very right: DNA is exactly such an aperiodic crystal and contains, with the rest of the cell, a microcode for the organism.
Two immediate features of Schrodinger’s wonderful guess are of interest to me:
The microcode is EMBODIED in the organism as a whole and BUILDS, in general, another organism, bacterium or fruit fly. Building requires real physical WORK to be done. Note that Shannon’s Information theory and Kolmogrov’s information theory are utterly devoid of information coming into existence, embodiment, or work. Nothing is built.
A note: By accident, the present post should have been posted last week, and last week's post should have been posted today. It may be useful to read the present post, and then, should you wish, read last week's post and my comments there for increased, I hope, clarity. — S. Kauffman
The universe is vastly complex. In my previous blog I pointed out that the fine tuning of the 23 constants of nature in the Standard Model and General Relativity were, perhaps, a necessary, but not a sufficient condition for our universe to have become complex.
We have no adequate theory for why our universe is complex. Indeed, I will say that we can have no such complete theory. But we can link fragments that may grow in time to a more integrated web of theory and observation.
To begin at the beginning, assuming the Big Bang. The universe started extremely hot, dense, and essentially uniform, or isotropic. Perhaps all four forces, Electro-Magnetic, Weak, Strong and Gravity really were united into a single unified force. A first essential to a complex universe is that it expanded and cooled. By cooling symmetries can be broken. Probably the first ones to be broken were those separating the four forces. If we accept Inflation in the very early universe, exponentially rapid expansion of early space solves the problem of why regions out of causal contact with one another due to the finite speed of light, and causal contact, are essentially uniform - the famous Horizon problem. Quantum fluctuations just before that Inflation are believed to lead to the 1/10,000 inhomogenieties in mass density that later congeled into first generation stars and galaxies that outlive their stars. Supernovae in some stars, and the nuclear reactions from hydrogen to all the heavier elements created the atomic distribution of atomic species in the universe.
Eric Chaisson’s Cosmic Evolution is a wonderful discussion of these processes. And in the last blog I noted his view, well supported, that the energy density per gram universe per second has increased over the course of cosmic, biological and cultural evolution. Energy per unit time is a “power”, so the power density per gram universe has gone up. A deep issue is how can this have happened? What would be a prototheory to account for this?
At present, I can only glimmer fragments. I hope they will build, either in these blogs or beyond, usefully.
I begin with the precient, brilliant insight of Schrodinger in “What is Life”, 1944, and before Shannon and Kolmogorov begat Information theory. Neither Shannon nor Kolmogorov tell us what information IS, only how much of it we have, where information came from in the evolution of the universe, nor what the semantics of that information is. All this disembodied information appears deeply mysterious, along with matter and energy. I think Shannon and Kolmogorov, brilliant, boarded the wrong boat.
Schrodinger wondered at the stability of life and the character of the gene. It had to be based on quantum mechanics, for the statistics of ink diffusing in a petri plate would not account for the heritable stability of life. So genes must be “solids”. Then Schrodinger lept: The gene would not be a “periodic crystal”. “Too dull”, is all he says. “Rather, the gene will be an “aperiodic crystal that contains a microcode for the organism.” How very right: DNA is exactly such an aperiodic crystal and contains, with the rest of the cell, a microcode for the organism.
Two immediate features of Schrodinger’s wonderful guess are of interest to me:
The microcode is EMBODIED in the organism as a whole and BUILDS, in general, another organism, bacterium or fruit fly. Building requires real physical WORK to be done. Note that Shannon’s Information theory and Kolmogrov’s information theory are utterly devoid of information coming into existence, embodiment, or work. Nothing is built.
The aperiodic crystal contains a high diversity of microconstraints which are boundary conditions that ENABLE a HIGH DIVERSITY OF ORGANIZED PROCESSES to happen in the universe.
In make my own leap, I claim that information IS such constraints that enable a diversity of organized processes to occur, and the simple “semantics” of the contraint is the process it enables. (Once we get to life and natural selection, the semantics will become the coordinated specific diversity of organized processes enabling life to propagate and improve by natural selection. The “semantics” broadens out to be the biological function of a given constraint enabled organized process.
Next, step: Where to asymmetric crystals and other things come from? By breaking symmetries. The universe started highly symmetric. So for assymetries to arise, those initial symmetries must have been, and even today, continue to be broken.
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Read more here/Leia mais aqui: NPR
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NOTA DESTE BLOGGER:
É aqui que Marcelo Gleiser publica primeiro, em inglês, seus artigos traduzidos publicados depois na Folha de São Paulo.
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