Fighting entropy
Chapter 1 - Worldview
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Welcome to the Fighting entropy page
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Living organisms like you and me are structured, organised networks of cells. We live together in organised groups. But entropy favours disorder over order; it seeks to break down these structured, organised networks of cells and people. In other words, entropy is the driving force behind ageing and death. You can fight it and stave it off for a time, but you can never defeat it.
You can't defeat entropy. The ending is written in stone from the second you enter the game. Because we can't beat entropy, our goal is to fight it.
An even more fundamental question is why and how life defeats entropy.
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Core idea
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The need for low-entropy energy
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| Fighting entropy |
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| How did complex systems emerge from chaos? Physicist Sean Carroll explains. |
| https://www.youtube.com/live/Sz1n0RHwLqA |
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A fundamental reality feature is that disorder increases. Batteries run out, cream and coffee mix, and ice cubes melt. If the one thing that reality does is move closer and closer to complete disorder, how did something as exquisitely organised as a human being come about?
Things tend to go from orderly to disorderly just because there are many more ways to be disorderly. This is a deep-down law of nature. It implies what we call the 'Heat death of the Universe': that all the stuff you see, the engines, the burning stars, the living beings, all represent systems that are increasing the overall entropy of the Universe. The Universe will reach an 'equilibrium': a state of maximum chaos in which nothing interesting happens anymore.
One issue with understanding the second law of thermodynamics is that it can be easy to confuse simple with complex and orderly with disorderly. The truth is that these are two different axes, two different ways of thinking about something.
- The increase in entropy indicates that we go from orderly to disorderly
- But it does not say anything about simple versus complex
What is the journey from low entropy to high entropy like, and how are the laws of physics affected so that the actual path it takes leads to complex structures? How did life emerge?
One of the difficulties in figuring out how life on Earth came into being is that it's not just a random complex system. It's very specific. Life as we know it now involves different aspects, all of which are important.
- You need replication
- You need Darwinian evolution. We have DNA. We have a genome that gets replicated, not perfectly, but pretty well
- You need compartmentalisation. Every cell has a cell wall so that you can separate the living cell from the rest of the world
- You also need metabolism. You need fuel; you need that low-entropy energy that we can use to keep ourselves going and then expel to the world in a higher-entropy form
Explaining the beginning of complex structures is always tricky because they all seem to depend on each other. The replication-first camp in the origin of life studies literature says, "Look, the genetic information is necessary to call it life; that must have come first, and it must have hooked up to an energy source." The metabolism-first camp says, "Look, it doesn't matter if you have information sitting there. If it's not going somewhere, if it's not doing anything, if it's not moving around and metabolising, you can't call it life." The nice thing about the metabolism-first point of view is that you can see how it might arise out of purely physical, non-biological processes because it maintains orderliness and complexity.
- Living beings need to increase the Universe's entropy; therefore, they need to feed on low-entropy energy.
So this was an idea that a number of biologists and geologists had. And on the basis of it, they made predictions. Life is not going to form in some warm pond. Darwin's idea was that you just put all the stuff together, all the ingredients, and eventually, a little bug crawls out. Or a little bacterium. And they said, look, that's never going to happen because there's no increasing entropy.
You need just the right biochemical and geological arrangement to have these long, sophisticated, complex reactions happen, which can then be captured into the first living organism. Geologists found the geochemical conditions that had been hypothesised to be possible places where life could have formed at the bottom of the Atlantic Ocean.
Does that mean it's right? No, but there is evidence that it could be on the right track.
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Negentropy
Negentropy, negative entropy (sometimes also called syntropy), is the entropy that an organism exports to keep its entropy level low. Negentropy is a central concept in the theory of entropy and life. The concept of negative entropy was first used in 1943 by Erwin Schrödinger in his book 'What Is Life?' Later, this term was shortened to negentropy by Léon Nicolas Brillouin to remove the negative connotation.
Negentropy is a portmanteau of “negative” and “entropy” and describes the difference between the energy in a system and the maximum possible energy in that system (at equilibrium, i.e., when it has its maximum possible entropy).
Erwin Schrödingerː "A meaningful interpretation of negentropy is that it measures the complexity of a physical structure in which quantities of energy are invested, e.g., buildings, technical devices, organisms but also atomic reactor fuel, the infrastructure of a society. In this sense organisms may be said to become more complex by feeding not on energy but on negentropy."
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Deep dive
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Key take-aways from the deep dive
- ecosystem designs that capture a previously untapped energy source persist
- there is a connection between thermodynamics and information processing
- the knowledge embedded in the most fundamental physical principles ensures development
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Maximum power principle
Alfred James Lotka (March 2, 1880 – December 5, 1949) was a Polish-American mathematician, physical chemist, and statistician famous for his work in population dynamics and energetics. Lotka proposed that natural selection was, at its root, a struggle among organisms for available energy.
Lotka's principle states that organisms that survive and prosper capture and use energy more efficiently than their competitors.
Lotka extended his energetics framework to human society. In particular, he suggested that shifting reliance from solar to nonrenewable energy would pose unique and fundamental challenges to society.
Lotka proposed that the Darwinian concept of natural selection could be quantified as a physical law. The law he suggested was that the selective principle of evolution favoured the maximum useful energy flow transformation.
The general systems ecologist Howard T. Odum later applied Lotka's proposal as a central guiding feature of his work in ecosystem ecology. Odum called Lotka's law the maximum power principle.
| "The maximum power principle can be stated: During self-organization, system designs develop and prevail that maximize power intake, energy transformation, and those uses that reinforce production and efficiency." |
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| Howard T. Odum - 1995 |
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| The principle of natural selection reveals itself as capable of yielding information which the first and second laws of thermodynamics are not competent to furnish. The two fundamental laws of thermodynamics are, of course, insufficient to determine the course of events in a physical system. They tell us that certain things cannot happen, but they do not tell us what does happen. |
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| A. Lotka - 1922 |
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| ...the maximum power principle ... states that systems which maximize their flow of energy survive in competition. In other words, rather than merely accepting the fact that more energy per unit of time is transformed in a process which operates at maximum power, this principle says that systems organize and structure themselves naturally to maximize power. Systems regulate themselves according to the maximum power principle. Over time, the systems which maximize power are selected for whereas those that do not are elected against and eventually eliminated. ... Odum argues ... that the free market mechanisms of the economy effectively do the same thing for human systems and that our economic evolution to date is a product of that selection process. |
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| Gilliland - 1978 |
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| The maximum power principle is a potential guide to understanding the patterns and processes of ecosystem development and sustainability. The principle predicts the selective persistence of ecosystem designs that capture a previously untapped energy source. |
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| T.T. Cai - 2006 |
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The deep relationship between physics and information theory
The thermodynamics of computation is a research focus of physicist David Wolpert, who collaborated with Artemy Kolchinsky to understand better the connection between thermodynamics and information processing in computation. If a person inputs “2+2” into a calculator and then hits “enter,” the computer outputs the answer: 4. At the same time, the machine loses information about the input since not only 2+2 but also 3+1 (and other pairs of numbers) can produce the same output. From the answer alone, the machine can’t report which pair of numbers acted as input. And if you erase a bit of information, you have to generate a little bit of heat.
Kolchinsky and Wolpert found a fundamental relationship between thermodynamic irreversibility, the case in which entropy increases, and logical irreversibility, the case in computation in which the initial state is lost. In a sense, they’ve strengthened the second law of thermodynamics.
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Constructor Theory
Constructor theory statesː
- If a task, a transformation, is impossible, it must be because there is some law of physics that makes it impossible
- Conversely, if there isn't a law of physics that makes it impossible, then it's possible
There is no third possibility. What does possible mean? In the overwhelming majority of cases, though some things are possible because they happen spontaneously,
- Things that are possible are possible because the right knowledge embodied in the right physical object would make them happen
Since the dichotomy is between that which is forbidden by the laws of physics and that which is possible with the right knowledge, and there isn't any other possibility.
This is counterintuitive. It's contrary to conventional wisdom, and it's contrary to our intuitive or at least culturally intuitive way of looking at the world. I find myself grasping for a third possibility. Isn't there something that we can't do even though there's no actual law of physics that says we won't be able to do it? Well, no, there can't be.
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| Constructor Theory |
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| What tasks are possible, what are impossible, and why |
| https://www.constructortheory.org/ |
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Constructor Theory of life
In her paper, Chiara Marletto explores the constructor theory of life, addressing how the appearance of purposive design in living organisms can arise without intentional design. Neo-Darwinian evolutionary theory fully explains this phenomenon: certain properties must exist in the laws of physics that allow for gene replication and natural selection without encoding biological adaptations. Under no-design laws, self-reproduction, replication, and natural selection are possible, with the primary condition being that these laws allow for the physical instantiation of digital information. Marletto shows that an accurate replicator requires a "vehicle" to form a self-reproducer under no-design laws.
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| Chiara Marletto - Constructor theory of life - The Royal Society - 2015 |
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