Not-directly-observable particles {virtual particle}| can exist for times shorter than force-interaction time. According to quantum-mechanics, virtual particles can spontaneously appear in space and then interact before observable time or space.
cause
In vacuum, mass, energy, and electric charge average zero. In space and in baryons, according to quantum-mechanics, mass, energy, and electric charge have random fluctuations above and below zero over time and space.
pairs
Virtual particles arise as pairs: quark-antiquark pairs, electron-positron pairs, photon pairs, and graviton pairs. To make average momentum be zero, zero-rest-mass virtual particles must form in same-particle pairs that travel in opposite directions. To make average charge be zero, virtual particles with mass must form in pairs, one with positive charge and one with negative charge. To make average energy be zero, virtual particles with mass must form in pairs, one with positive energy and one with negative energy.
antiparticles
Uncertainty principle allows virtual particles to move faster than light, and relativity requires that particles that move faster than light must go backward in time. By relativity and quantum mechanics, charge moving backward in time is equivalent to opposite charge moving forward in time. Particles and antiparticles must have opposite charges. Virtual particles go forward in time. Virtual antiparticles move backward in time.
As an electron moves through space-time, moving observers see different electron velocities, and some see electron moving backward in space-time.
As an electron moves through space-time, it can change velocity twice. This is equivalent to an electron-positron virtual-particle pair arising at the second velocity-change point, the virtual positron going backward in time to annihilate the original electron at the first velocity-change point, and the virtual electron continuing on from the second velocity-change point as a real electron.
objects
All protons, neutrons, atoms, and molecules have virtual particles at all times. In atoms, virtual negative charges stay closer to positively-charged nucleus, and virtual positive charges stay closer to negatively-charged electron orbits. Because virtual particles continually spontaneously appear and then annihilate, all objects always have virtual-particle distributions and complicated mass, energy, and/or charge distributions. Dirac's relativistic-quantum-mechanics equations can account for all virtual-particle distributions, to any accuracy degree, by including primary, secondary, tertiary, and/or higher levels of virtual-particle creation and annihilation. The virtual-particle distribution accounts for most proton, neutron, atom, molecule, and object mass, so quarks and electrons are only a small part of object mass.
energy
By uncertainty principle, more-energetic virtual particles have shorter times. Long-lived-virtual-particle energies have lifetimes of 10^-8 seconds, so long-lived-virtual-particle energies are 1.22 * 10^-16 GeV, or 6 x 10^-13 electron masses. Times can be as short as Planck time, 10^-43 seconds, so short-lived-virtual-particle energies are 1.22 * 10^19 GeV, or 6 x 10^22 electron masses. Higher energies are more infrequent. By uncertainty principle, total energy is finite but very high, equal to 10^120 times universe mass-energy. To make vacuum energy average zero, space vacuum must have negative energy (dark energy) almost equally high, to cancel. This space energy makes space expand.
conservation laws
Because, by uncertainty principle, short times and small spaces have high energies and momenta, virtual particles do not necessarily conserve energy and momentum.
experiments
Exciting hydrogen atoms with microwaves moves electrons from s to p orbitals (Lamb shift), and electromagnetic-field quantum fluctuations make virtual particles. In mass-173-atom nucleus, strong electric field can produce real particle from virtual particle.
theory
Perhaps, real particles are detectable parts of virtual-particle clouds around particles.
theory: infinities
In quantum mechanics, because virtual particles can arise spontaneously at any point and time, for any particle process the number of possible particle paths is infinite. In particular, electron mass and charge become infinite. In quantum electrodynamics, quantum chromodynamics, and electroweak theory {Weinberg-Salam theory}, renormalization cancels infinities. In quantum-gravity theories, masses and their secondary interactions can be large, so renormalization is not always possible. (In string theories, strings have vibration states, with no infinities.)
Physical Sciences>Physics>Matter>Particle
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Date Modified: 2022.0224