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Fundamental Physics. or. Wolfram vs. Einstein, Podolsky, Rosen, Bell, Schrödinger, Bohr, Heisenberg, Planck, Born, Minkowski, Schwarzschild, Misner, Thorne, Wheeler, …. A Few Simple Constraints. It’s all in the definition…. Wolfram’s Alternatives. Cellular Automota Networks
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Fundamental Physics or Wolfram vs. Einstein, Podolsky, Rosen, Bell, Schrödinger, Bohr, Heisenberg, Planck, Born, Minkowski, Schwarzschild, Misner, Thorne, Wheeler, …
Wolfram’s Alternatives • Cellular Automota • Networks • Multidimensional Substitution Systems • Mobile Automota • Multiway Systems
Thermodynamics • The first law of thermodynamics says you can’t win. (Conservation of mass-energy) • The second law says you can’t even break even. (Entropy can never decrease reversible processes must have no change in entropy)
Wolfram Inconsistencies • Demands an explanation for why the 2nd law of thermodynamics must be true, but is willing to accept 1st law. • Will discard cellular automata that violate reversibility, but not those that violate the 2nd law.
Conserved Quantities • Demonstrates systems that conserve various features. Cellular automata should only be considered models – conserved quantities can be considered mass-energy, 4-momentum, lepton number, etc. (Electron number is not conserved!) • Does not demonstrate systems that conserve more than one feature at a time, e.g., mass-energy and 4-momentum.
Nature of Space • Do not confuse Wolfram’s constraint to only consider systems with three connections with Wolfram claiming that these are the only systems possible.
Relationship of Space and Time • If universe is really a mobile automata, we do not need to invoke a master clock to keep track of time. Each node sees changes since last visit as happening simultaneously. • This predicts significantly different results than special relativity, but it’s only one example!
Sequencing of Events • Considers several type of substitution systems. • First substitution: the first possible substitution is used. • All substitution: all possible substitutions are used. • Random substitution: of all possible substitutions, one is chosen at random. • What does random mean in this context?
Sequencing of Events • Investigates rules where differing orders of replacement do not produce different causal networks to deal with lack of a global clock. • These rules also have a concept of simultaneity that differs from special relativity.
Uniqueness and Branching in Time • Wolfram’s multiway system almost matches the many-worlds interpretation of quantum mechanics. • More paths leading to a state increase the number of universes experiencing that state.
Evolution of Networks • Uses a LRU algorithm • Addresses tie-breaking conflicts by examining rules that are order independent
Space, Time and Relativity • Fundamental concept of relativity is that the universe can be divided into five sections, relative to an event • Time-like past • Light-like past • Space-like • Light-like future • Time-like future
Space, Time and Relativity • Wolfram’s causal networks divide the universe into three sections, relative to an event • Events that caused this event (directly or indirectly) • Events that are independent of this event (might have common causes or effects) • Events caused by this event (directly or indirectly)
Space, Time and Relativity • Nearby means events that can be reached in a small number of hops • If one considers something a meter away to be nearby, then small means ≤ 1035 • If two events separated by a second to be nearby, then small means ≤ 1043 • EPR pairs might then be considered to have a wormhole between them! (This is not the typical interpretation.)
Space, Time and Relativity • An approximate definition of relative simultaneity can be constructed by: • Picking an event that simultaneity will be defined relative to. (Event A) • Choosing an event far in the future of event A. (Event B) • Finding all events that are the same number of hops from event B as event A. These events approximate simultaneity relative to event A. None of these events can cause or be caused by A. • As event B approaches an infinite number of hops from event A, this approximation approaches true relative simultaneity.
Elementary Particles • Hand-waving and resorting to authority • Provides some very high-level interesting concepts, but shows no way of exploring them – even in the notes • Mentions lots of technical details that have been derived by others, seemingly to imply that all of them can be explained by his model
Gravity • Discusses several possible geometries, but mainly more hand waving • Still resorts to tensors in the notes • Does have the consistent effect that his elementary particle postulates would naturally imply distortion of space-time
Quantum Phenomena • Suggests that quantum phenomena are deterministic • In order to explain basic results, seems to contradict hand-waving on elementary particles
EPR Pairs • His solution to EPR pairs seems to involve a virtual wormhole between pairs – this violates the standard theory which suggests that no information can be communicated “faster than light” with these pairs
Bell’s Inequalities • Seems to believe that experiments violating Bell’s inequalities are flawed • Closely related to quantum computing