- panspermia, 1
- parallel realities, 1
- particles
- instantaneous influence, 1
- location vs momentum, 1, 2
- nature’s most fundamental, 1
- in two places at once, 1
- wave-like behaviour, 1
- see also alpha particles; electrons; neutrinos; neutrons; photons; positrons; protons; quarks
- Pauli, Wolfgang, 1, 2
- Pauli effect, 1
- Pauli exclusion principle, 1
- Payne, Cecilia, 1
- Penrose, Roger, 1
- Penzias, Arno, 1
- Pérignon, Dom, 1
- Perrin, Jean Baptiste, 1
- phases, 1
- photocells, 1
- photoelectric effect, 1, 2
- photons
- behaviour, 1, 2, 3
- Big Bang photons, 1, 2, 3
- and dark matter, 1
- and electromagnetism, 1
- infrared, 1
- lack of rest mass, 1
- non-locality, 1
- Planck, Max, 1
- Planck length, 1
- Planck temperature, 1
- plasma, 1
- plum-pudding model, 1
- Pluto, 1
- plutonium, 1, 2
- Podolsky, Boris, 1, 2
- Poe, Edgar Allan, 1, 2
- polonium, 1
- positrons, 1
- potassium, 1
- Pouillet, Claude, 1, 2
- probability waves, 1
- probes see Von Neumann probes
- proton chain, 1
- protons
- composition, 1
- and hydrogen fusion, 1, 2
- as nuclear building blocks, 1
- Prout, William, 1, 2
- pulsars, 1