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Origin Story

A Big History of Everything

David Christian

First annotation on . Last on .

32 quotes

world-history

Chapter 2

  • Structured flows of energy is an intuitive description rather than a piece of scientific jargon. But here’s the idea it’s getting at: Thermodynamic theory distinguishes between energy flows that are completely random and energy flows that have direction, structure, and coherence so they can do work. Structured flows of energy are known as free energy, and unstructured flows are known as heat energy. The difference is not absolute. We’re really talking about degrees of coherence or randomness. Nevertheless, the distinction between free energy and heat energy is fundamental to our origin story.Oct 5 2023 11:14AM
  • The first law of thermodynamics tells us that the total amount of energy in the universe never changes. It is conserved. Our universe seems to have arrived with a fixed potential for things to happen. So the first law is really telling us about the primordial ocean of possibilities. The second law of thermodynamics tells us that the things that emerge from the ocean of possibilities can be more or less structured, like the ripples in a stream. But we should expect most of them to be less structured and become even less structured over time. That is because most possible arrangements of matter and energy have little or no structure, and if by chance you do find structure, expect it to decay fast.Oct 5 2023 11:15AM
  • But unlike energy in general, free energy is not conserved. It’s unstable, like an uncoiling spring. As it does work, it loses both its structure and the ability to do more work.Oct 5 2023 11:15AM
  • Heat energy, like a drunken traffic cop, directs energy every which way and creates chaos. Free energy, like a sober traffic cop, directs energy down particular routes and creates order.Oct 5 2023 11:16AM
  • Free energy drove the emergence of the first large structures: galaxies and stars. The crucial source of free energy for this part of our origin story was gravity. Like a cosmological sheepdog, gravity likes to herd things. And the things it herded were the simple forms of matter created in the big bangOct 5 2023 11:23AM
  • Newton saw gravity as a universal force of attraction that operated between all masses. Two and a half centuries later, Einstein showed that energy could also exert a gravitational pull, because energy is what matter is made from.Oct 5 2023 11:30AM
  • In 2017, three of the men who contributed significantly to the project were awarded the Nobel Prize in Physics. The gravitational waves LIGO detected were generated about one hundred million years ago, when two black holes collided in a distant galaxy somewhere in the southern skies. (When they collided, dinosaurs still ruled our planet.) On Earth, each LIGO machine split beams of light in two and sent them traveling at right angles to each other up and down two four-kilometer tubes with mirrors at either end. When they returned after almost three hundred trips, they didn’t arrive at exactly the same time. Tiny gravitational waves had stretched the tubes in one direction and shrunk them in the other by a distance much less than the width of a proton.Oct 5 2023 11:32AM
  • From the point of view of gravity, the early universe was too smooth. It needed to be clumped up. This tendency of gravity to rearrange the universe explains why we can think of the early universe as having low entropy, a sort of tidiness that entropy could mess up over the next few billion years. Once it got going, gravity took just a few hundred million years to turn the smooth particle mist of the early universe into a messier and lumpier space full of stars and galaxies.Oct 5 2023 11:33AM
  • As gravity forced atoms together, they collided more often and jiggled more frenetically. That drove up temperatures in the clumpier regions, as more heat was concentrated in smaller volumes of space. (The same principle explains why a tire gets warmer when you pump it up.) While most of the universe kept cooling, the clumpy bits began to heat up againOct 5 2023 11:34AM
  • Each star has a hot core in which protons fuse together, generating energy that pushes back against gravity. Above the core, outer layers press down and supply it with proton fuel. The star’s life history will depend primarily on its birth mass: how much stuff it contains at the start. Massive stars generate more gravitational pressure, so they are much hotter than stars with less mass. This explains why they burn their fuel fast and shut down within just a few million years. Stars with less mass burn more slowly, and many small stars will keep burning for much longer than the present age of the universe.Oct 6 2023 9:55AM
  • But there’s a puzzle here. What about the second law of thermodynamics? Entropy hates structure, so why does it allow more complex things to appear?Oct 6 2023 10:05AM
  • The idea of a complexity tax helps explain an important phenomenon noted by the astrophysicist Eric Chaisson: roughly speaking, more complex phenomena need more dense flows of energy, more energy per gram per second. He estimates, for example, that the density of energy flowing through modern human society is about one million times greater than the density of energy flowing through the sun, while energy flowing through most living organisms lies somewhere between these extremes.Oct 6 2023 10:10AM
  • Hydrogen and helium were the first elements to be made because they are the simplest. Hydrogen has one proton in its nucleus, so we say it has atomic number 1. Helium has two protons in its nucleus, so its atomic number is 2. When the CMBR was emitted, about 380,000 years after the big bang, there was also a sprinkling of lithium (atomic number ) and beryllium (atomic number 4). And that was it. These were the only elements created in the big bang.Oct 6 2023 5:11PM
  • For astronomers, there is one fundamental map that brings together a huge amount of information about stars: the Hertzsprung-Russell diagramOct 6 2023 5:12PM

Chapter 3

  • In truth there are only atoms and the void. —DEMOCRITUSOct 7 2023 9:36AM
  • Chemistry is all about the trysts and the wars inside these probability mists. And there’s a lot going on. Bonds are formed and broken between protons and electrons, old ties are ended, new relationships are started, and the result is the emergence of entirely new forms of matter.Oct 7 2023 9:37AM
  • Like human lovers, electrons are unpredictable, fickle, and always open to better offers. TheyOct 7 2023 10:15AM
  • chemistry. Some electrons jump ship and head for neighboring atoms. If they do that, the atom they left will have lost a negative charge, so it may pair up with an atom that has an extra electron to form an ionic bond. This is how salt is formed from atoms of sodium, whose outermost electron is usually willing to jump, and chlorine, which is often looking for an extra electron to fill up its outer orbit.Oct 7 2023 10:17AM
  • Carbon, with six protons in its nucleus, is the Don Juan of these atomic romances. It normally has four electrons in its outer orbit, but there is room enough there for eight, so you can make a carbon atom happy by removing four electrons from its outer shell, by adding four electrons, or by letting it share four electrons with another atom. This gives it a lot of options, and that is why carbon can form complicated molecules with rings, chains, and other exotic shapes. Its virtuosity explains why carbon is so important to the chemistry of life.Oct 7 2023 10:17AM
  • Geologists divide Earth’s history into subdivisions, the largest of which is the eon. The first is the Hadean (“hell-like”) eon. This lasted from when Earth formed to about four billion years ago, when the Archean eon began. If you’d visited during the Hadean eon, you’d have found a planet still affected by the demolition derby of accretionOct 7 2023 10:34AM
  • In 1788, James Hutton wrote: “We find no vestige of a beginning, no prospect of an end.”Oct 7 2023 10:35AM

Chapter 4

  • The spooky thing about life is that, though the inside of each cell looks like pandemonium—a sort of mud-wrestling contest involving a million molecules—whole cells give the impression of acting with purpose.Oct 7 2023 10:39AM
  • Something inside each cell seems to drive it, as if it were working its way through a to-do list. The to-do list is simple: () stay alive despite entropy and unpredictable surroundings; and () make copies of myself that can do the same thing. And so on from cell to cell, and generation to generation. Here, in the seeking out of some outcomes and the avoidance of others, are the origins of desire, caring, purpose, ethics, even love. Perhaps even the beginnings of meaning, if that means the ability to discriminate between the significance of different events and signs.Oct 7 2023 10:39AM
  • But living things are different. They don’t accept entropy’s rules passively; instead, like stubborn children, they push back and try to negotiate. They don’t just lock structures in place, like protons or electrons. They don’t live off stores of energy, like stars, which munch their way through a larder of protons that was well stocked at their birth and then fall apart when the larder is empty. Living organisms constantly seek out new flows of energy from their environments in order to maintain themselves in a state that is complex but unstable.Oct 7 2023 10:40AM
  • Unlike the complex physical systems we have seen so far, the components of which behave in ways that can usually be predicted from the universe’s basic operating rules, the components in complex adaptive systems seem to have a will of their own.Oct 7 2023 10:41AM
  • Indeed, complex adaptive systems, such as bacteria, your dog, or multinational companies, act as if every component is an agent with a will of its own, so each component is constantly adjusting to the behavior of many other components. And that yields extremely complex and unpredictable behaviors.Oct 7 2023 10:41AM
  • If agents react to other agents, they are reacting to information about what is happening around them, including information about what other agents are doing. If we imagine information as a character in our modern origin story, we should think of it as working undercover or in disguise, manipulating events but staying out of the spotlight.Oct 7 2023 10:42AM
  • Energy causes change, so you can usually see it at work, but information directs change, often from the shadows. As Seth Lloyd puts it: “To do anything requires energy. To specify what is done requires information.”Oct 7 2023 10:42AM
  • One of the most famous definitions of information is “a difference which makes a difference.”Oct 7 2023 10:42AM
  • Entropy, of course, keeps a beady eye on all of this. If more complexity means more information, then when you increase complexity and information, you are reducing entropy and its accompanying uncertainty or disorder. And entropy will notice. Entropy is rubbing its hands at the thought of the energy taxes and fees it can levy as complexity and information increase. Indeed, some have argued that entropy actually likes the idea of life (and may encourage it to appear in many parts of the universe), because life degrades free energy so much more efficiently than nonlife.Oct 7 2023 10:44AM
  • Cells really are like cities. In a book on cells, Peter Hoffmann writes: There is a library (the nucleus, which contains the genetic material), power plants (mitochondria), highways (microtubules and actin filaments), trucks (kinesin and dynein), garbage disposals (lysosomes), city walls (membranes), post offices (Golgi apparatus), and many other structures fulfilling vital functions. All of these functions are performed by molecular machines.Oct 7 2023 10:45AM
  • Darwin’s idea, when linked to a modern understanding of genetics and heredity, explains life’s creativity, its ability over many generations to explore possibilities, tap new energy flows, and construct new types of structures. It explains how, in the biological realm, structures of staggering complexity can emerge through repetitive algorithmic processes as they are filtered out from myriad variations, step by step and generation by generation, over millions and billions of years.Oct 7 2023 10:47AM

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