Friday, 16 February 2018

Before and after Isaac Newton

Lent 2018: Day Three

"With Newton, we became disenchanted, and entered modernity," writes Stuart A. Kauffman, quoting sociologist Max Weber. The Enlightenment was indeed a hinge of history. It led directly to the Industrial Revolution (which couldn't have happened without Science, empirical, repeatable, objective) and the modern age. A modern age offering modern man more than we need.

Isaac Newton's thinking did not emerge from a vacuum. It was based on the observations and measurements of Pythagoras, Euclid, Archimedes, Plato, (then after a pause for the Dark Ages) Copernicus, Galileo and Descartes. The Newtonian revolution was the birth of classical physics. "The conceptual framework invented by Newton is stunning in its brilliance, for its pervasive brilliance and for the hold it retains over our minds. Newton remains our dominant model for how to do science.

Defining the universal law of gravity, Newton used differential equations of motion, allowing scientists to deduce the forward trajectories of moving bodies such as planets and their satellites. Newtonian physics holds that the the Universe is causally closed. Taken further, French mathematician Pierre-Simon Laplace postulated a 'demon' who knew the positions and momenta of all particles in the universe. Such a demon could calculate, on the basis on Newton's differential equations, the entire future and past history of the Universe.

Fundamental laws, standing outside the Universe, that "just are."

This changed Mankind's view of God. From a deity that intervenes in our day-to-day lives, sending hurricanes, pestilence, earthquakes or other tribulations to try us, God became the Creator that wound up the Universe, set its immutable laws... and stood back.

For the Church, the birth of modern science was a challenge to its authority. I have written about this in my 2013 Lenten series of essays (Tischner-Żakowski, click for link). As  Kauffman puts it: "With Newton, all that changed: we are entirely law governed." Fundamental laws, that can be scientifically measured, determine how things are, were and will be - not a God with a long white beard. This is what Alexander Pope had in mind when he wrote "God said let there be Newton, And all was Light."

But the deterministic Newtonian world view would begin to fracture within a couple of centuries. The uncertainty inherent in quantum mechanics denied Laplace's demon the ability of calculate anything at all in the sub-atomic world. And not long before the birth of quantum physics, Henri Poincaré developed the chaos theory in mathematics - dynamic systems that are highly sensitive to initial conditions. The weather is one such example of a chaotic system. "Two 'infinitely close' initial positions and momenta can follow trajectories that veer apart becoming 'exponentially' more distant with time... determinism no longer implies predictability, for we cannot measure initial conditions to infinite accuracy," explains Kauffman.

And so although the Newtonian order was already being undermined in mathematics and in physics, Newton's reductive materialism maintained a powerful hold on our minds "by the mid-20th century, we found ourselves in a meaningless universe. Consider Steven Weinberg, Nobel physicist, who wrote not long ago, "The more we know of the universe, the more meaningless it appears"," says Kauffman, pointing out that Weinberg's Dream of a Final Theory shows him to be a believer in the triumph (one day) of reductive materialism in which everything is entailed by natural laws." In philosophy, the mid-20th century existentialism of Sartre and Camus depended on a meaningless Universe.

Along came quantum mechanics. Kauffman explains the concept of light - photons - being waves and particles at the same time, something first shown in Thomas Young's double-slit experiment (1801!). This is sufficiently important to be expanded over five pages. I, however, would merely suggest you have a look at the Wikipedia page about the experiment - the notion that photons, particles which can be waves have no mass and move at the speed of light is quite amazing to ponder over.

Quantum mechanics also gave us Heisenberg's Uncertainty Principle (1927), which states that the more precisely the position of some particle is determined, the less precisely its momentum can be known, and vice versa. And the similar Observer Effect, which posits that simply observing a situation or phenomenon necessarily changes that phenomenon - in other words, that measurements of certain systems cannot be made without affecting the system.

Now, if uncertainty reigns in the subatomic world - how does that square with the determinism of Newton's reductive materialism?

Wikipedia warns us against going too far in rejecting Newtonian determinism: "[the uncertainty principle and observer effect] findings have led to a popular misconception that observation by a conscious mind can directly affect reality, though this has been rejected by mainstream science. This misconception is rooted in a poor understanding of the quantum wave function ψ and the quantum measurement process."  Despite him quoting parapsychologist Dean Radin, Kauffman is not going to let himself go down the road of New Age mysticism. Kauffman's aim is rather to question the "rampant scientism that plagues us and blinds us", railing against "'the hard-headed realist' stance in a world now devoid of mystery... I admire reductive materialism; I seek... not to deny it, but to destroy its hegemony over our minds and set  us free."

More soon!

This time last year:
Historical turning point: which way now?

This time two years ago:
Coincidence and consciousness 

This time four years ago years ago:
North-east of Warsaw West revisited

This time five years ago:
Looking for answers

This time six years ago:
Fresh powder in Warsaw's parks

This time eight years ago:
Another Lent starts

This time ten years ago:
Okęcie dusk

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