Growing up in the Milky Way Galaxy (with apologies to Timothy Ferris)
Watching the stars was the way Humanity figured out where it was in the cosmos.
You can't tell if you don't look
Science is an ever growing body of knowledge that continues to expand exponentially. This points to a singularity sometime in the near future. We've built machines that can imitate speech (passing the Turing test[A] soon.) And it all started with a singularity in the past where Humanity learned to speak.
When did science start? Did it start in pre-history? Before people could write? Does science include the ability to make stone tools and slowly improve them so they are easier to use and more efficient? Of course. Science is the observation of objective reality and the ability to construct models with reproducible predictions. Take two rocks of a certain type and shape and bang them together this way and you get a hand axe. It’s magic! Not a miracle but real magic. An incantation with the right ingredients can use the recipe to get a predetermined outcome. Real Magic.
Granted, it’s not very complicated Magic. Two types of stone and one procedure to figure out where to knock them together. Any old monkey could do this. It probably doesn’t require any complicated language to make these simple hand tools. These tools are the earliest example of science that have survived to the present day. These tools evolve very slowly without changes for hundreds of thousands of years. The changes are glacial at this first attempt at technology [3.3 M yrs ago, possible Australopithecus, but certainly Homo Habilis, ancestors of Homo Erectus, Mode 1, Oldowan ]
The rate of evolution is slow. Almost as slow as the evolution by natural selection of our ancestors. And it proceeded by the same process, small random changes, like a game of telephone tag over the ages.
The ancestors that created there tools were not our current species, Homo Sapiens, they were Homo Erectus and they spread all over the world from Africa. The first stone tools are found about two and a half million years ago. And they slowly evolve for about a million years, we find and are able to date them all over the world. About a million years ago the rate of change of new tools starts to exponentially speed up. It's obvious at this point that we can talk. Not just name things, but actually converse. [Homo Erectus Mode 2, Acheulean tools, which are much more complicated, require complex planning and make butchering much simpler.]
Then the next few modes of stone tools come quickly. This is all still during pre-history, before we can write, but after we could talk. [Mode 3, Shaft connected heads, pikes and arrows in modern parlance]
This seems like the beginning of science to me. The slow growth through practice and observation of the ability to understand and control the environment by using a constructed apparatus: a tool. People are still nomadic at this point. Homo sapiens migrate to North America around 30,000 years ago and continue to evolve stone technology [Clovis points] separately from the rest of the world. It’s still a pre-literate society at this point. Everything is passed down by word of mouth. Game is plentiful. Counting coupe is useful. All is well.
The next innovation to occur, that changed how we defined ourselves as human beings, was the domestication of plants and animals. Farming. Ranching. (Eventually Feudalism: domestication of people.) [Sometimes we forget what has changed and how much it has changed.] owning and controlling land was now valuable and could be used to support many more people than before domestication. And defense is easier than offense. You need about three times the number of attackers to defenders to ensure victory. So large settlements became larger for their own survival.
Above the size of a few hundred people a small town could run without anyone in charge except one priest being literate enough to resolve inheritance issues but a city needed to have records, taxes, tithes, laws, rights, ownership, responsibilities and duties. They needed a way to record these transactions, debts and payments, interest rates and money. Accounting was required to run a city. Accounting had to be reliable and reproducible, just like science. It’s a tracking of the promises made, kept and owed between human beings.
It’s marks on a slate. How much are your taxes this year? Ten bushels of wheat to be delivered on October 15th at the central Grainery. And if you didn’t deliver it, you got fined. You couldn’t deny your bill, it’s right there in front of you, a picture that tells you what you have to deliver. This one small thing makes large permanent cities possible. They start in the Middle East and spread this system around the world.
Not just accounting, but also literacy. A recording of the rules that govern a citizens rights and duties. Literacy allows the Magic to be written down and accumulated in books. What is this Magic? It’s the formal system of universal computation. How to write down the information needed to complete any recipe for a predicted outcome from baking a cake to building a car to designing a government to specifying a moral or legal code. There’s an incantation on how to do it right and fairly. Science is the same way, but science is limited to the investigations and observation of objective reality. There are three branches of science: the study of atoms (models of objective reality), the study of life (emergent behavior) and the study of formal systems (possible models.)
Accounting continues to evolve to become more sophisticated. Double entry bookkeeping becomes the norm. [reference] except for accounting, the ancient Greeks attribute everything to the gods. Zeus throws thunderbolts. Neptune makes the winds blow. It’s an easy explanation… except things happen in cycles. There are up to four distinct seasons everywhere. The moon cycles overhead every thirty days. There are eight other lights in the sky that move along the same general path. These wanderers (or planets [reference from Greek]) follow their own cycles. And there were eclipses. And they suggested patterns. There are hints that stone henge and other historical buildings recognize the alignment of the stars and the seasons.
It was critical to know when to plant and when and how to fertilize and harvest. This has only gotten more sophisticated over the centuries including further domestication of plants and animals through the direct modification of their genes. Farmers use satellite photos supplemented by ground measurements to determine pesticide, water and fertilizer dosage. The methods of Science play a huge part in this progressive drive to make our live’s more efficient.
But science is more than that. The scientific method is a way to translate measurements into meaning. Or at least into predictions that allow you to argue about the meaning. The first recorded use of the “Accounting” method of explanation was in 2000 BCE [reference Greek? Macedonian?] by Anaximander where he proposed the rain cycle and what causes earthquakes.
He was basically correct in the first instance and deeply wrong (wind) on the second. But it was a model, a blameless model (Not that one of their gods did it, which was their previous explanation.) It’s amazing that the first models were wrong half the time. Actually science is almost always wrong. It just gets more accurate as time moves on. Aristotle. Copernicus. Kepler. Newton. Galileo. Laplace. Einstein.
This the beginning of Science with a capital S. Financed by city-states, more for war than anything else. Increasing the “kill-radius” of weapons to the ridiculous point of destroying the entire planet! Finally in the 80s the realization of nuclear winter got everyone to stop practicing nuclear explosions in the open air. See, humans can be sensible sometimes!
What makes up the Scientific method? It’s a model of the ‘situation’ or formally a theory is a set of universal laws, recipes, or formulas that can be used to make predictions. The genius Newton showed us how to build a model from scratch. How to define the terms, define the experiments, the measurements and predictions and publish his formulas so that anyone can use them to reproduce his results and generate new results. And he showed that his predictions were more accurate than the old Greek system (which was pretty damn accurate.) The giant’s shoulders that Newton stood on included Kepler.
But the real giant was Copernicus. [reference] He took the model presented by the Greeks, that was highly accurate, by the way, (as demonstrated by the Antikythera [reference]) and proposed it was not the simplest way to look at the solar system. Humanity was not at the center of the universe, there were no spheres within spheres within spheres (although that was an ever more complicated but quite accurate model.) The simpler view was that the Earth was a planet like all the wanderers and they all circled the sun.
And furthermore, the Earth was a top, always pointing in one direction. To first order it explained everything. The seasons. [diagram] But it wasn’t as accurate as the old Greek model. Careful measurements showed significant deviations (Circles vs. ellipses, for instance.) Measurements made by Tyco Brahe were used by Kepler to propose his three laws of planetary motion. He examined the data and noticed systematic deviations that could be explained by assuming that the orbits were ellipses not circles. This is a replacement of the Greek model centered on the Earth. It was a solar centric model. Brahe had his own model where the sun went around the earth and all the other planets went around the sun. The interesting thing is they are all correct. The math works out wherever you pick the center to be. Some choice of coordinate systems are more illustrative than others. There’s just one objective reality and you can assume the universe rotates around any point in it, or not.
That’s not to say that scientists weren’t proponents for their own views. Tycho made his observations without the aid of any optics. He used accurate timing and long deep shafts to determine the angle to make accurate measurements. He may be the first scientist in the modern sense of the word. He was financed by the city-state, as was Kepler.
Kepler had the years of Brahe’s measurements to use and he had optical telescopes to verify and reproduce the measurements. Brahe’s measurements were accurate up to one arcminute. That’s about a thirtieth of the width of the moon or about the amount the moon moved in one minute. Kepler proposed three laws of planetary motion based on Brahe’s measurements of Mars.
1. The planets orbit the sun, which is at the focal point of the elliptical orbit.
2. Equal areas are swept out over equal times.
3. The orbital period squared is proportional to the semi-major axis cubed.
Kepler presented his results at the Royal society in London and was heralded as a great triumph of astronomy. Newton reads the published laws and derives them using mathematics he invented for the purpose (calculus) but doesn’t bother to publish the discovery, he’s a poor graduate student and can’t afford to. Halley (of Halley’s Comet) hears this and offers to pay to publish the greatest scientific work of all time: the Principia Mathematica that explains the first Scientific theory: Newtons laws of motion. He showed that all three of Keplers laws could be deduced in his system from one fact: that bodies attract each other proportional to their mass and inversely proportional to the square of the distance between them.
This theory of gravity proposed by Newton is highly accurate, but not exact. As almost all physics theories are incorrect in some small form or manner. There were nagging questions about how much did gravity affect starlight and how fast mercury’s orbit preceded that told us it wasn’t exact. It took the genius of Einstein to build a more accurate model that looked like Newton’s law in all known physical situations, and in other weird situations (high speeds, large masses) it looked different and it explained all the anomalies and predicted a bunch more things tangential to gravity. Einstein’s theory of gravity has been tested to an amazing degree and it has never been found to be wanting.
As in the most respected physics theories. It’s eminently falsifiable. And like the best theories, it has passed all of its tests. Everywhere we look we see Einstein’s theory playing out in the cosmos. Before Einstein’s time the naked eye and an accurate clock we’re used to make astronomical measurements. All you can see are planets and stars, maybe some meteoroids or comets, just photons and nothing else.
Astronomy has gone far beyond just photons. First we noticed that there are things beyond stars. Other galaxies like our Milky Way galaxy, full of stars, and that they were traveling away from us, the further away, the faster they were going. The universe was at least a million times, if not a billion times bigger than we had ever imagined. Here’s the galaxies the Hubble Space Telescope sees in an area the size of a dime held at arms length.
Galaxies seen by the Hubble Space telescope in a patch of sky the size of a dime at arm's length.
And if you extrapolate back in time, at one point all the galaxies are on top of each other in one ‘Big Bang’ as the theories biggest opponent described it, attempting to ridicule the idea (Fred Hoyle, a distinguished astronomer, scientist and popularizer of the day.) We measure how far away these galazies are and how fast they are traveling and find the distance is proportional to the velocity. The only way to explain this is to assume the Big Bang actually happened.
Cosmic Microwave background, differences from a perfect black body.
Deviations from the perfect black body radiation curve.
[A] https://en.wikipedia.org/wiki/Turing_test
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