General relativity, quantum mechanics, cosmology, and logic contribute to theories of how universe began {universe-origin theories}. The universe had no beginning or began as white-hole space-time singularity, as quantum foam, as quantum branes or loops, or from nothing [Adams, 2002] [Barrow and Tipler, 1986] [Greene, 1999] [Greene, 2003] [Kauffman, 1993] [Mach, 1896] [Mach, 1906] [Price, 1996] [Rees, 1997] [Rees, 1999] [Rees, 2001] [Sklar, 1977] [Smolin, 1997] [Weinberg, 1972] [Weinberg, 1992] [Weinberg, 1993] [Weyl, 1952].
energy
By observation and calculation, at universe origin, space had smallest volume, same total energy as now, and highest energy density. Highest energy density made greatest space curvature, which is consistent with smallest 3-sphere volume. Because beginning universe was smallest volume, distances were shortest, and potential energy was lowest, so kinetic energy and temperature were highest.
energy: conservation in closed universe
By observation, universe has no energy influx from outside universe or energy outflow to outside universe. Universe total energy is constant.
energy: positive
Universe attractive forces, mainly gravity, cause positive energy, so objects have positive potential and kinetic energy. Local positive energy density varies with both rest-mass and relativistic-mass distributions.
energy: dark energy
By observation (Brian Schmidt) [1998], universe has repulsion that is expanding space, so space has negative intrinsic energy. Negative-energy causes uniform space expansion and so does work to add intrinsic negative energy to added space. Because space-expansion volume varies directly with intrinsic-energy work, space has constant negative intrinsic-energy density. Therefore, space has had constant dark-energy density since universe began. By calculation, universe has 70% dark energy and 30% matter. The future will disclose what dark energy is.
energy: amount is arbitrary
Because only energy changes have physical significance, absolute energy amount has no physical meaning. Energy level is arbitrary, so energy level is only relative, not absolute. Any physical state can be set to zero energy, and other states differ in energy from that state. For example, in earth's gravitational field, potential energy can be zero at Earth's surface or zero at infinite distance. If physical states can have arbitrary energy levels, total universe energy amount is arbitrary.
By special and general relativity, energy amounts are relative to reference-frame observer velocity. For example, for high-velocity observers, kinetic energy can be zero. If reference frame is arbitrary, total universe energy is arbitrary.
Photon energy varies directly with electromagnetic-wave frequency. Moving relative to light sources changes wave frequency and so observed photon energy. For observers moving away from source at high velocity, frequency red-shifts to near zero. For observers moving toward source at high velocity, frequency can blue-shift to arbitrarily high values. Because observer reference frame is arbitary, total universe photon energy is arbitrary.
energy: space vacuum
By observation, universe space curvature is close to zero, so universe average energy density is close to zero, meaning positive average mass-energy density and negative average intrinsic-energy density are close to equal. Closed universes do not change total energy, so average positive energy density and average negative energy density stay close to equal for closed universes.
Empty space has no energy from mass or relativistic mass, so space vacuum is set to zero average energy density. Other-states energy densities are relative to vacuum-state energy density.
energy: highest
Because shortest quantum-mechanical wavelengths mean highest frequencies, shortest spaces and times require highest energy (uncertainty principle), and universe began with shortest diameter, so universe began with highest energy density.
Universe has wide number ranges. Gravitational force has no limit in distance or amount. Strong force to gravitational force ratio is about 10^40. Because forces have wide ranges, universe can have wide energy ranges.
In empty space, positive energy density and negative energy density can be arbitrarily high, as long as positive energy density equals negative energy density so that energy density is zero. Universe can have arbitrarily high energies and energy fluctuations. Energy fluctuations can temporarily reach energy densities great enough to make particles.
general-relativity singularity
Because energy density, internal pressure, and gravity were highest, general relativity theorizes that universe began as a space-time singularity. Universe was a point both in and out of space-time. Singularities have smallest space volume and greatest space curvature. Singularities have perfect symmetry, homogeneity, unity, and order. Perhaps, all universes are similar.
quantum-mechanics closed universe
Because empty-space distances are shortest, space vacuum has uncertainty-principle energy fluctuations that can be large enough to make particles. Because both closed universes and space vacuum have zero energy flux, zero average energy density, and high energy-density variance, closed universes can arise spontaneously and randomly from space vacuum. Boundary conditions determine universe properties.
multiverse
If closed universes arise spontaneously from existing space vacuum, the number of space points is infinite. An infinite number of universes, with different laws and properties, can arise. Alternatively, each universe that has cosmic inflation has an infinite number of space points at which sub-inflations can spontaneously arise. Because space expands rapidly and separates them, the universes are independent.
quantum field theories
Quantum field theories show how particles and antiparticles arise in strong force fields, how virtual particles make force fields, and how space and time arise.
Quantum electrodynamics shows how time arises in strong force fields. Strong electromagnetic and weak-force fields make non-linear-wave time quanta (instanton), lasting for one electronic transition or one quantum tunneling.
Quantum gravity shows how space arises in strong gravitational fields. Strong gravitational fields make non-linear-wave space quanta, over one Planck distance, area, or volume, from no space and no time, and so start spaces with zero average energy density.
Therefore, strong fields can make space and time quanta and so start universes. Boundary conditions determine universe properties.
quanta
Universe space, time, energy, and momentum have non-zero minima and increase by discrete amounts (quanta). Particle energy quanta vary directly with quantum-mechanical resonating-wave harmonic frequencies (and particle momentum quanta vary inversely with quantum-mechanical resonating-wave harmonic wavelengths). Lowest-energy quanta associate with fundamental frequency. Because they have higher energy, higher-frequency quantum states have lower probability.
quanta: discrete non-zero energy levels
If protons and electrons can have zero-energy states, electrons can spiral into atomic nuclei, preventing atoms from existing. Particles and waves exist for long times and so have non-zero minimum energy.
If protons and electrons can have energy states that vary continuously, orbits can continuously decay, and electrons can spiral arbitrarily close to atomic nuclei, preventing atoms from existing. Discrete states maintain orbits, because moving from lowest orbit to no orbit cannot conserve energy, momentum, and angular momentum simultaneously. Particles and waves exist for long times and so have discrete energy levels.
If energy can vary continuously, particles and waves can have infinitesimal energy increases, each with the same small finite probability, so total energy can become infinite with measurable probability (ultraviolet catastrophe). If energy can vary only by discrete amounts, higher-energy increases have lower probability, so infinite total energy has zero probability. Higher-energies have lower probabilities, so particles and waves have discrete energy levels.
virtual particles
Physical-mathematical operators that conserve quantities, such as energy conservation, have average quantity zero. For commutative operators, operation order does not matter, so they have one more symmetry: variance quantity zero. Non-commutative operators that conserve quantities have average quantity zero but variance quantity non-zero. Action in physics multiplies energy and time non-commutatively, so action has energy fluctuations with zero averages but positive or negative variances (uncertainty principle). Space vacuum has short distances and high momenta, and short times and high energies. Therefore, space vacuum can have high enough positive or negative energy fluctuations to spontaneously create short-time energy quanta (virtual particles). Because particles are numerous, even low-probability high-energy-density states occur within moderate times, so space vacuum makes numerous virtual particles.
By observation, two positive-energy virtual particles (particle-pair) can arise spontaneously and simultaneously from empty space. Two particles allow charge and momentum conservation. The virtual particles have zero or opposite charges.
By observation, after short lifetime over small distance, virtual particles interact with zero-charge or opposite-charge virtual particles and spontaneously and simultaneously disappear, making two photons of electromagnetic energy.
The creation-and-annihilation process conserves mass-energy over long enough times and wide enough lengths.
In quantum mechanics, energy fields are streams of virtual-particle zero-rest-mass photons, zero-rest-mass gravitons, massive strong-force bosons, or massive weak-force bosons emitted from charges, masses, quarks, or leptons, respectively. Photons and gravitons are zero-rest-mass bosons that both propagate at light speed, so electromagnetism and gravity have effects over infinite distances.
antiparticles
By observation, when a particle meets its antiparticle, the particles annihilate, canceling electric charge and converting all mass to photons of electromagnetic energy. All quantum numbers become zero. Therefore, antiparticles always have charge opposite to that of their particles.
Both matter and antimatter have positive mass and attractive gravity. Antimatter does not have antimass or repulsive antigravity. Because they are the exact opposite of particles, antiparticles must have the same mass as their particles.
By special relativity, particles can only move forward in space-time. When a particle moving forward in space-time meets its antiparticle, momentum cancels, mass cancels, and only energy remains. Because particles and antiparticles have same mass and speed, momentum cannot cancel if antiparticles move forward in space-time, so antiparticles move backward in space-time. Because a particle and its antiparticle annihilate, a particle moving forward in space-time is equivalent to its antiparticle moving backward in space-time.
In quantum mechanics, all possible particle and antiparticle trajectories have wavefunctions and probabilities, and space-vacuum quantum energy fluctuations make virtual particles and antiparticles with measurable probabilities. By observation, a real particle can disappear at one location, and then a real particle can re-appear at the same time at a nearby location. Space-vacuum quantum energy fluctuations made the particle's virtual antiparticle arise earlier in space-time where the particle re-appeared. The virtual antiparticle went backward in space-time to where the particle disappeared and annihilated it at the observed time, the same time as the particle re-appeared at the nearby location.
antiparticles: antimatter
At universe beginning, because matter and antimatter have same physical laws and processes, universe had equal matter and antimatter amounts. Matter-antimatter annihilations made radiation, which is part of cosmic microwave background radiation. During annihilation, weak-force parity-and-time asymmetries left one part matter (and no antimatter) after every billion annihilations, so universe has only some matter: one proton for every billion radiation photons.
electric charge
At universe origin, very high temperature unified the strong force, weak force, and electromagnetism, so quark creation and lepton creation coupled. That coupling balanced positive and negative charge creation, so universe has no net charge.
dark matter
By calculation, stars move faster in their galactic orbits than galaxy visible and non-visible ordinary matter can make them move, and galactic-cloud ordinary-matter mass does not make enough gravity to form galaxies, so galaxies must have more matter (dark matter) than just ordinary matter. By calculation, universe has nine times more dark matter than ordinary matter. Dark matter is invisible, because it does not interact with electromagnetic radiation. The future will disclose what dark matter is.
time
Universe began a definite time ago, and observations indicate that universe will keep expanding indefinitely, so past time was not infinitely long ago, but future time will be or approach infinite time.
space
By observation, space is isotropic and homogeneous and probably began that way.
By calculation and observation, universe began with finite volume, and space has expanded ever since. Space expansion has reduced object gravitational attraction, space curvature, and outward kinetic energy. By observation, space expansion rate is increasing, so space will expand faster. Universe has large volume now and will approach infinite volume.
space: curvature
By general relativity, positive space curvature reduces distances, and negative space curvature increases distances. Because observed cosmic-microwave-background-radiation irregularities equal expected cosmic-microwave-background-radiation irregularities [1997], space on average has no curvature.
By calculation, universe average mass-energy density (positive and attractive) equals average dark-energy density (negative and repulsive), so space on average has no curvature.
space-time
Space and time unite in continuous space-time. By special relativity and experiment, time dimension relates to space dimensions by light speed: time-dimension time times light speed is space-dimension length. All objects move through space-time at light speed. Space-time has no time flow or direction, so space-time represents all previous and future times in the same way as spatial dimensions represent all points in all directions.
space-time: why was space three-dimensional?
Space is where energy is, so energy makes space. More space dimensions means more energy but less energy density. Zero space dimension has no energy and no energy density. One space dimension makes energy be one-dimensional longitudinal waves, so energy is too low and energy density is too high. Two space dimensions make energy be longitudinal and one-plane-transverse waves, so energy is too low and energy density is too high. Three space dimensions make energy be longitudinal and two-coordinate transverse waves, so energy density not too low or too high. Four space dimensions make energy be longitudinal and three-coordinate transverse waves, so energy is too high and energy density is too low.
Continuous four-dimensional space-time is stable and allows motion, potential, and energy. Space-time is unstable with more than three spatial dimensions and/or more than one time dimension, because gravity is too weak. With two or fewer space dimensions, kinetic energy is too small, and space does not expand. With four or more space dimensions, kinetic energy is too great, and space expands rapidly to make near vacuum.
space: expansion
At universe origin, although energy density and internal pressure were highest and so gravity was highest, space had smallest possible volume, and random-motion kinetic energy was highest and overcame gravity greatest, so space expansion rate was highest. However, because gravity was highest, expansion-rate decrease rate was greatest.
entropy
Planck-size discrete units have information bits. At universe origin, volume was smallest, so entropy was lowest.
Beginning universe had smallest volume, fewest allowable number of dimensions, fewest states, fewest information bits, most force symmetries, no matter, highest energy, and highest temperature, all of which make entropy lower, so total universe entropy was lowest.
Continuous systems have infinitesimal energy increases, each with the same small finite probability, and so infinitely many possible states. Discrete systems have lower-probability higher-energy states, so entropy is lower.
entropy: fractal processes
Perhaps, to minimize volume and dimension number, beginning universe had fractal processes. Fractal processes have high order and so low entropy. Moreover, fractal processes can make unlimited energy and energy ratios, because they repeat indefinitely.
symmetries and conservation laws
At universe origin, space-time, general relativity, quanta, and quantum mechanics began. Beginning universe had deterministic physical laws with time, space, and handedness symmetries.
Because physical laws are the same for forward and backward time (isochrony), space-time has energy conservation (least action over time), so universe total energy stays constant.
Because physical laws are the same for any space direction (isotropy), space-time has momentum conservation (least action over distance), so universe has no net motion.
Because physical laws are the same for right-handed and left-handed systems (symmetry), space-time has angular-momentum conservation (least action over rotation), so universe has no net rotation.
Future physical theories will account for all universe properties, including universe origin and its properties.
Physical Sciences>Astronomy>Universe>Cosmology
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Date Modified: 2022.0224