How Determinism Emerges from an Indeterministic World
There Was No Determinism In The Early Universe Before About 400 Million Years
The first "information structures" that formed in the universe were the elementary sub-atomic particles produced when the temperature and density of radiation fell below values where particles could be stable against immediate destruction by high-energy photons. The first particles were quarks, electrons, and baryons (atomic nuclei), and these were the only particles for about 380,000 years. At this time the temperature cooled to about 3000 degrees Kelvin, below which electrons could combine with nuclei to form the first atoms (the next "information structures").
It would be 400 million years before the temperature and density were low enough to allow the relatively weak but extremely long-range gravitational force to pull together masses large enough to become planets, stars, and galaxies following Newtonian laws of motion.
"Adequate" determinism and classical mechanics first
emerged in the early universe, but the
appearance of determinism emerges every day in bodies large enough to average over the indeterministic behavior of individual particles.
Heisenberg's indeterminacy principle
Δp Δx ≥ h tells us the indeterminacy in momentum and position. Just as relativistic effects can be ignored when the velocity of an object is arbitrarily small compared to the velocity of light (when v / c → 0), some argue that quantum effects can be ignored when Planck's quantum of action
h goes to zero.
But this is a mistake. For an object at rest, v / c = 0, but the quantum of action
h never changes. All physical systems are fundamentally quantum.
Quantum mechanics is universal. The indeterminacy in the position and
velocity of a large macroscopic object can become arbitrarily small if we replace the momentum
p with
mv and rewrite the indeterminacy relation as
Δv Δx ≥ h / m. It is when the mass
m is large and
h / m approaches 0 that quantum effects can be ignored and the object treated as
adequately determined for most practical purposes and as a "classical" object.
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