2
" Even if a particle could travel backward in time, information could not. Retrocausality will be replaced by something more sophisticated. There are no perfect symmetries, there is no pure randomness everything is an approximation of something else. Information may appear in a digital form but meaning never does. Spacetime is built up from approximations, not discrete ones and zeros, and the only constant may be ratios. Quantum entanglement and geometry; if we think of a particle as being at one pole of an expanding sphere that is not perfectly symmetrical, this surface would be " rippling" like the surface of the ocean (in the audio world this is called dithering), at the other pole is the entangled particle's pair and it is a property of the sphere that gives the illusion of connectivity. This is not a physical geometry, it is a computational geometry. Is spacetime a product of entanglement? Renate Loll believes that time is not perfectly symmetrical. Her computer models require causality. Possibly some form of quantum random walk in state space. If a photon is emitted by an electron inside of a clock on Earth and it travels to a clock four light years away, time stops for the clock on Earth and time jumps forward eight years for the distant clock also, the electron that will capture the photon becomes infinitely large relative to the photon but the electron that emitted it does not become infinitely small therefore, time is not perfectly symmetrical. "
11
" Evolution endowed us with intuition only for those aspects of physics that had survival value for our distant ancestors, such as the parabolic orbits of flying rocks (explaining our penchant for baseball). A cavewoman thinking too hard about what matter is ultimately made of might fail to notice the tiger sneaking up behind and get cleaned right out of the gene pool. Darwin’s theory thus makes the testable prediction that whenever we use technology to glimpse reality beyond the human scale, our evolved intuition should break down. We’ve repeatedly tested this prediction, and the results overwhelmingly support Darwin. At high speeds, Einstein realized that time slows down, and curmudgeons on the Swedish Nobel committee found this so weird that they refused to give him the Nobel Prize for his relativity theory. At low temperatures, liquid helium can flow upward. At high temperatures, colliding particles change identity; to me, an electron colliding with a positron and turning into a Z-boson feels about as intuitive as two colliding cars turning into a cruise ship. On microscopic scales, particles schizophrenically appear in two places at once, leading to the quantum conundrums mentioned above. On astronomically large scales… weirdness strikes again: if you intuitively understand all aspects of black holes [then you] should immediately put down this book and publish your findings before someone scoops you on the Nobel Prize for quantum gravity… [also,] the leading theory for what happened [in the early universe] suggests that space isn’t merely really really big, but actually infinite, containing infinitely many exact copies of you, and even more near-copies living out every possible variant of your life in two different types of parallel universes. "
― Max Tegmark , Our Mathematical Universe: My Quest for the Ultimate Nature of Reality