Universe history {cosmology}| cycles between endpoints (oscillating theory), is unchanging (steady-state theory), or began by space expansion {universe, history} {universe, origin} [Greene, 1999] [Mach, 1885] [Mach, 1906] [Rees, 1997] [Rees, 1999] [Rees, 2001] [Smolin, 2001] [Weinberg, 1972] [Weinberg, 1977 and 1993] [Weinberg, 1992] [Weyl, 1952].
before universe
Perhaps, before universe origin, there was only nothingness, there was already space and/or time, or there were also mathematical and/or physical laws.
Nothingness has properties. Nothingness has no time or space and so no dimensions. It has no ground-state, zero, or complex-number energy, because it has no dimensions and so no motions or fields. It has no matter, motions, forces, fields, radiation, energy, temperature, or pressure. It is homogeneous and has only one phase. It has no quanta. It has zero entropy. Perhaps, by uncertainty principle, nothingness can create relativistic quantum-mechanical virtual particles.
Perhaps, universes spontaneously arise from empty space, if space has negative energy, which causes space expansion.
Perhaps, mathematical/physical laws cause universes to arise, if they imply space and time.
dimensions
If universe has no time dimension and any number of space dimensions, or any number of time dimensions and no space dimension, motion, energy, momentum, and space-time do not exist.
If universe has one or more time dimensions and more than three spatial dimensions, gravity and electromagnetism strength decrease more quickly with distance, so star and planet orbits and electron orbits, respectively, are too lightly bound and are unstable. With one or more time dimensions and fewer than three spatial dimensions, gravity and electromagnetism decrease less quickly with distance, so stars and planets and electrons quickly move to center, and stars, planets, and electrons do not exist.
If universe has more than one time dimension and one space dimension, fields are unstable. If universe has more than one time dimensions and more than one space dimension, physical events are unpredictable.
Electron current, magnetic field, and atom radius define three space dimensions, so electromagnetism requires at least three infinite spatial dimensions. Space cannot have more than three infinite spatial dimensions, because then electron current, magnetic field, and atom radius have two or more independent relations for electric and magnetic fields.
String theory and brane theory require three infinite spatial dimensions and seven or eight curled-up spatial dimensions. Quantum-loop theory defines three infinite spatial dimensions.
Perhaps, dimension number, length, and geometry were or are in flux. Dimension number varies from zero to infinite. Dimension lengths vary from zero to infinite length. Dimension geometries vary from linear to curved to curled up. Perhaps, dimensions evolve by physical processes to stable numbers, lengths, and geometries. Perhaps, energy and matter distributions dynamically determine dimension number, length, and geometry. Perhaps, multiverses or different universe regions have different dimensions.
Perhaps, beginning universe had zero dimensions. Perhaps, because fewer dimensions make lower entropy, universe has four-dimensional space-time because it has lowest entropy consistent with maximum energy. Perhaps, universe has optimum number, length, and geometry of space-time dimensions to allow highest number of states, most stability, and most symmetries. Perhaps, universe is like one fiber bundle, with one n-sphere as base space.
space expansion
Universe expands at same rate at all points and in all directions equally.
At its origin, universe had maximum space expansion rate. Gravity is attractive and slows expansion rate. If universe average mass-energy density is high enough, gravity eventually stops expansion, and then universe contracts back to singularity. If expansion rate had always been smaller by 10^-10 than it was, universe collapses back to singularity in one million years.
If universe average mass-energy density is low enough, gravity never stops space expansion, and universe expands at ever slower rate. If universe average mass-energy density is even lower, gases cannot condense, and galaxies and stars do not form. If expansion rate had always been greater by 10^-10 than it was, universe is like empty space in one million years. Therefore, space expansion rate has been and will be such that universe will expand to infinity, at which expansion rate will finally be zero.
entropy
At universe origin, entropy was minimum. If early-universe entropy per baryon was more, no protogalaxies form. Universe entropy is always increasing. Perhaps, universe expansion contributes to increasing universe entropy.
density variations
At neutral-charge atom formation, with matter-radiation decoupling, 300,000 years after universe origin, if universe had too-slight mass-energy density irregularities, gravity does not form galactic clusters, no protogalaxies form, and no galaxies form. If universe had slighter mass-energy density irregularities than it does, galaxies are farther apart and have fewer and smaller stars. If universe had too-great mass-energy density irregularities, galaxies are smaller and have bigger stars, so stars become dark and cool more quickly.
Cosmic microwave background radiation has variations over space. Cosmic microwave background radiation polarization has fundamental frequency and wavelength, as well as C1-dipole, C2-quadrapole, and C3-octopole multipoles. Dark energy makes ecliptic C2 and C3 multipoles align with equinoxes and solar-system-motion direction, not be random as required by inflation theory. Dark energy makes some C2 and C3 multipoles align with Milky-Way-and neighboring-galaxy supergalactic plane, not be random. Dark energy makes some C2 and C3 multipoles lower intensity than higher-C multipoles, though inflation theory requires that all multipoles have same intensity. Dark energy makes cosmic-microwave-background-radiation intensity variation over space separations greater than 60 degrees not correlate with that at smaller separations, though inflation theory requires that all separation distances have same intensity variation.
gravitation
Gravity binding-energy-to-rest-mass ratio is 10^-5, so gravity is weak. If ratio was higher, matter clustering is so great that gravity is stronger than dark energy, soon overcomes initial space expansion, and contracts matter into giant black holes. If ratio was lower, gravity is too weak to cluster matter, no galaxies or stars form, and space expands faster forever.
If dark energy was too little and gravity was too much, universe quickly re-collapses. To prevent quick contraction, matter and dark matter must be less than three times universe dark energy. If dark energy was too much and gravity was too little, universe expands before atoms can form or galaxies can form. To allow galaxy formation, dark energy must be less than 140% of universe mass.
Quantum gravity or other combination of gravitation and quantum mechanics determines universe origin. Perhaps, universe origin involved quantum-mechanical tunneling.
gravity: internal pressure
Mass m has energy E: E = m * c^2, where c is light speed. Mass can convert to kinetic energy, which causes external pressure. Increased kinetic energy increases temperature, and increased temperature pushes particles farther apart against gravity, increasing positive potential energy and making positive internal pressure. In general relativity, at space-time points, gravity G depends on mass-energy density M plus three times internal pressure P: G ~ M + 3*P. Solids do not change volume at constant temperature, so they have zero internal pressure. Hot gas has more positive potential energy than cold gas and so has more internal pressure and more gravity. Photons have zero rest mass but have radiation pressure that makes internal pressure P one-third mass-energy density M, so gravity doubles: M + 3 * (M/3) = 2*M.
electromagnetism
Electromagnetic radiation can transport energy over infinite distances. Electromagnetism determines inorganic-and-organic-chemical bonding and reactions. If electromagnetic force was stronger, electrons fall into protons, and atoms do not form. If electromagnetic force was weaker, electrons are too fast for capture in atom orbits, and atoms do not form. For example, if electromagnetism was only 4% weaker, hydrogen atoms cannot form.
If protons were 0.2 percent more massive, protons decay to neutrons. If electron and proton charge was slightly different, electrons cannot orbit protons, and atoms do not form.
strong force
Strong nuclear force holds atomic-nucleus protons together and determines fission and fusion reactions. Strong-nuclear-force strength determines star energy radiation and atomic-nuclei radioactivity levels. If strong force was stronger, only large atomic nuclei form, and no hydrogen persists. For example, if strong nuclear force was only several percent stronger, carbon cannot form from beryllium and helium. If strong nuclear force was 2% stronger, protons cannot form from quarks. If strong force was weaker, only small atomic nuclei form. For example, if strong nuclear force was 2% weaker, small nuclei are unstable.
strong nuclear and electromagnetic forces
Universe strong nuclear force and electromagnetic force have relative strengths that allow stable deuterium, stable carbon, few radioactive atoms, stable stars, and weak gravity. If strong nuclear force was stronger and electromagnetic force was same, stars explode. If strong nuclear force was weaker and electromagnetic force was same, deuterium is unstable. If strong nuclear force was same and electromagnetic force was stronger, carbon is unstable. If strong nuclear force was stronger and electromagnetic force was stronger, all atoms are radioactive.
weak force
Weak nuclear force determines fission and fusion reactions, radioactivity from nuclei, and planet melting. If weak force was stronger, nuclear fusion is faster, stars live shorter, and heavy elements cannot form. If weak force was stronger, universe has less dark matter, because, in first second of universe, dark matter stays in equilibrium with other matter longer. If weak force was weaker, nuclear fusion is slower, stars live longer, and hydrogen cannot form. If weak force was weaker weak, universe has more dark matter.
force unity
At 10^-43 seconds (Planck time) after universe origin, with universe at 10^32 K, all forces and interactions have Planck time, so all forces are the same {unity of forces}. Higher temperature makes gravitation increase greatly in strength (because internal pressure is more), weak force increase in strength (because average distance is smaller), electromagnetism change little (because radiation can have any frequency), and strong force decrease in strength (because average distance is smaller). Therefore, at universe origin, with highest temperature, all forces become equal in strength (and in other properties). Space expansion cooled universe and broke symmetry, so first strong force separated, and then electromagnetism and weak force separated.
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Date Modified: 2022.0224