# Index of physics articles (P)

The index of physics articles is split into multiple pages due to its size.
To navigate by individual letter use the table of contents below.

## Index of physics articles

* 0–9
* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z

## P

* P-adic quantum mechanicsfpa
* P-factor
* P-form electrodynamics
* P-nuclei
* P-process
* P-type semiconductor
* P-wave
* P-wave modulus
* P. Buford Price
* P3M
* PACER (fusion)
* PANDA experiment
* PAR thrust
* PEPS effect
* PETRA
* PGM-19 Jupiter
* PHENIX
* PHOBOS experiment
* PHOSFOS
* PICASSO
* PIND
* PITZ
* PLATYPUS
* PLUTO reactor
* PM3 (chemistry)
* POLYGON experiment
* POVM
* PQS (chemical)
* PS210 experiment
* PSR B1828-10
* PSR B1913+16
* PSR J0737-3039
* PSR J1614–2230
* PUREX
* PVLAS
* PVT (physics)
* PWscf
* PYTHIA
* Padma Kant Shukla
* Padre Bancalari
* Painlevé paradox
* Pair-instability supernova
* Pair annihilation
* Pair distribution function
* Pair potential
* Pair production
* Pake doublet
* Pakistan Institute of Nuclear Science and Technology
* Pakistan Physics Society
* Panayotis Varotsos
* Pandemonium effect
* Panemone windmill
* Panofsky Prize
* Pantur Silaban
* Paolo Casati
* Papaloizou–Pringle instability
* Papapetrou–Dixon equations
* Papkovich–Neuber solution
* Parabolic trajectory
* Parabolic trough
* Parachor
* Paracrystalline
* Paraelectricity
* Parafoil
* Paraformer
* Parallax barrier
* Parallel Worlds (book)
* Parallel axis theorem
* Parallelogram of force
* Paramagnetism
* Parameterized post-Newtonian formalism
* Parametric array
* Parametric oscillator
* Parametric resonance
* Parasitic drag
* Parastatistics
* Parawing
* Paraxial approximation
* Parfocal lens
* Parhelic circle
* Paris' law
* Pariser–Parr–Pople method
* Parity (physics)
* Parity anomaly
* Parker Variable Wing
* Parker spiral
* Parney Albright
* Parry arc
* Parry–Daniels map
* Parson magneton
* Partial pressure
* Partial wave analysis
* Particle
* Particle-in-cell
* Particle-induced X-ray emission
* Particle-size analysis
* Particle-size distribution
* Particle (disambiguation)
* Particle Data Group
* Particle acceleration
* Particle accelerator
* Particle aggregation
* Particle astrophysics
* Particle beam
* Particle counter
* Particle decay
* Particle detector
* Particle displacement
* Particle experiments at Kolar Gold Fields
* Particle horizon
* Particle identification
* Particle image velocimetry
* Particle in a box
* Particle in a one-dimensional lattice
* Particle in a ring
* Particle in a spherically symmetric potential
* Particle number
* Particle number operator
* Particle physics
* Particle physics and representation theory
* Particle physics in cosmology
* Particle radiation
* Particle segregation
* Particle shower
* Particle size
* Particle size (general)
* Particle statistics
* Particle tracking velocimetry
* Particle velocity
* Particle velocity level
* Particle zoo
* Particulates
* Partition function (quantum field theory)
* Partition function (statistical mechanics)
* Parton (particle physics)
* Parton distribution function
* Parvez Butt
* Parviz Moin
* Pascal's barrel
* Pascal's law
* Pascal (unit)
* Paschen's law
* Paschen series
* Paschen–Back effect
* Pascual Jordan
* Pasotron
* Passive Underwater Fire Control Feasibility System
* Passive radiator
* Patch dynamics (physics)
* Path-ordering
* Path integral Monte Carlo
* Path integral formulation
* Path integral molecular dynamics
* Pati–Salam model
* Patricia Lewis (physicist)
* Patrick Blackett, Baron Blackett
* Patrick N. Keating
* Patrick Tabeling
* Patrick d'Arcy
* Patterson function
* Paul-Quentin Desains
* Paul A. Fleury
* Paul Alfred Biefeld
* Paul Auguste Ernest Laugier
* Paul Callaghan
* Paul Chaikin
* Paul Chun (professor)
* Paul Corkum
* Paul Davies
* Paul Dirac
* Paul Drude
* Paul E. Klopsteg
* Paul Ehrenfest
* Paul Erman
* Paul Fillunger
* Paul Flory
* Paul Frampton
* Paul G. Hewitt
* Paul G. Richards
* Paul Garabedian
* Paul Gerber
* Paul Ginsparg
* Paul Halpern
* Paul Harteck
* Paul Horowitz
* Paul John Ellis
* Paul Kunz
* Paul Langevin
* Paul Lauterbur
* Paul M. Doty
* Paul Mackenzie
* Paul McEuen
* Paul Moskowitz
* Paul Neményi
* Paul O. Müller
* Paul Painlevé
* Paul Palmer (physicist)
* Paul Peter Ewald
* Paul Richard Heinrich Blasius
* Paul Rudolph (physicist)
* Paul Scherrer
* Paul Scherrer Institute
* Paul Sophus Epstein
* Paul Steinhardt
* Paul Taunton Matthews
* Paul Townsend
* Paul Ulrich Villard
* Paul Weiss (nanoscientist)
* Pauli equation
* Pauli exclusion principle
* Pauli group
* Pauli matrices
* Pauline Morrow Austin
* Pauli–Villars regularization
* Pavel Cherenkov
* Pavel Jelínek
* Pavel Petrovich Parenago
* Pavle Savić
* Pawsey Medal
* Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics
* Peak expiratory flow
* Peak kilovoltage
* Peak signal-to-noise ratio
* Peakon
* Pearl vortex
* Peccei–Quinn theory
* Peculiar motion
* Peculiar velocity
* Peder Oluf Pedersen
* Pedro Paulet
* Peierls bracket
* Peixoto's theorem
* Pelindaba
* Pelletron
* Pencil (optics)
* Pendulum
* Pendulum day
* Pendulum rocket fallacy
* Peng Huanwu
* Penguin diagram
* Penning mixture
* Penning trap
* Penrose criterion
* Penrose diagram
* Penrose graphical notation
* Penrose interpretation
* Penrose process
* Penrose transform
* Penrose–Hawking singularity theorems
* Pentamirror
* Pentaprism
* Pentaquark
* Per-Olov Löwdin
* Per Arne Rikvold
* Per Bak
* Per Carlqvist
* Percentage of the speed of light
* Percolation
* Percolation critical exponents
* Percolation theory
* Percolation threshold
* Percus–Yevick approximation
* Percy Williams Bridgman
* Peregrine soliton
* Perfect Cosmological Principle
* Perfect conductor
* Perfect fluid
* Perfect gas
* Perfect lens
* Perfect mirror
* Perfectly Reasonable Deviations from the Beaten Track
* Perhapsatron
* Perifocal coordinate system
* Perigean spring tide
* Perimeter Institute for Theoretical Physics
* Period-doubling bifurcation
* Period 9 element
* Periodic poling
* Periodic table
* Periodicity (metamaterials)
* Periodogram
* Perley Ason Ross
* Perley G. Nutting
* Perlin noise
* Permeability (electromagnetism)
* Permeability constant
* Permeameter
* Permeance
* Permeation
* Permittivity
* Perovskite (structure)
* Perpendicular axis theorem
* Perpetual motion
* Perpetual motion machine
* Perrin friction factors
* Persis Drell
* Persistence length
* Person-rem/year
* Perturbation theory
* Perturbation theory (quantum mechanics)
* Perturbative QCD
* Perveance
* Pervez Hoodbhoy
* Peskin–Takeuchi parameter
* Peter A. Sturrock
* Peter A. Wolff
* Peter Armbruster
* Peter B. Lyons
* Peter Barham
* Peter Bergmann
* Peter C. Aichelburg
* Peter Coles
* Peter Collinson (botanist)
* Peter Coveney
* Peter D. Jarvis
* Peter Debye
* Peter Demos
* Peter Dollond
* Peter Edwards (chemist)
* Peter Fowler (physicist)
* Peter Franken
* Peter Freund
* Peter Galison
* Peter Goddard (physicist)
* Peter Goldreich
* Peter Grünberg
* Peter Guthrie Tait
* Peter Haynes (mathematician)
* Peter Herbert Jensen
* Peter Heszler
* Peter Higgs
* Peter Hirsch (metallurgist)
* Peter Huybers
* Peter Hänggi
* Peter Knight (scientist)
* Peter Kramer (physicist)
* Peter Lax
* Peter Littlewood
* Peter Lu
* Peter Mansfield
* Peter Mazur
* Peter Pershan
* Peter Smith (physicist)
* Peter Stilbs
* Peter Thejll
* Peter V. E. McClintock
* Peter Wadhams
* Peter Westervelt
* Peter Woit
* Peter Zimmerman
* Peter Zoller
* Peter van Nieuwenhuizen
* Petr Beckmann
* Petr Hořava (theorist)
* Petr Paucek
* Petr Vaníček
* Petrophysics
* Petrov classification
* Petrus Peregrinus de Maricourt
* Petzval field curvature
* Pfeiffer Effect
* Pfund series
* Phantom energy
* Phase-coherent holography
* Phase-contrast imaging
* Phase (matter)
* Phase (waves)
* Phase Noise
* Phase compensation
* Phase contrast microscope
* Phase contrast microscopy
* Phase distortion
* Phase factor
* Phase noise
* Phase offset modulation
* Phase plane
* Phase portrait
* Phase problem
* Phase retrieval
* Phase space
* Phase space formulation
* Phase switch
* Phase transition
* Phase velocities
* Phase velocity
* Phased-array optics
* Phased array
* Phased array ultrasonics
* Phenomenology (particle physics)
* Phi meson
* Phil Williams (Welsh politician)
* Philip Abelson
* Philip Beckley
* Philip Burton Moon
* Philip Dee
* Philip J. Dolan
* Philip J. Morrison
* Philip L. Roe
* Philip M. Morse
* Philip Morrison
* Philip Russell (physicist)
* Philip Saffman
* Philip Warren Anderson
* Philipp Carl
* Philipp Lenard
* Philipp von Jolly
* Philippe Guyot-Sionnest
* Philippe Nozières
* Philippine Nuclear Research Institute
* Philo of Byzantium
* Philolaus
* Philosophical Magazine
* Philosophical Transactions of the Royal Society A
* Philosophical interpretation of classical physics
* Philosophiæ Naturalis Principia Mathematica
* Philosophy of physics
* Philosophy of space and time
* Philosophy of thermal and statistical physics
* Phobos (experiment)
* Phon
* Phonomotor
* Phonon
* Phonon drag
* Phonon noise
* Phononic crystal
* Phosphor
* Phosphor thermometry
* Phosphorescence
* Phosphoroscope
* Phoswich detector
* Phot
* Phot. Nano. Fund. Appl.
* Phot Nano Fund Appl
* Photo-Carnot engine
* Photo-Dember
* Photobleaching
* Photochromic lens
* Photoconduction
* Photoconductive atomic force microscopy
* Photoconductivity
* Photodetector
* Photodisintegration
* Photodissociation
* Photoelastic modulator
* Photoelasticity
* Photoelectric effect
* Photoelectric efficiency
* Photoelectric sensor
* Photoelectrochemical processes
* Photoemission spectroscopy
* Photoexcitation
* Photofission
* Photographic lens design
* Photographic magnitude
* Photographic plate
* Photoinduced charge separation
* Photoinduced phase transitions
* Photoionisation
* Photoionisation cross section
* Photolithography
* Photoluminescence
* Photomagnetic effect
* Photomagnetism
* Photomagneton
* Photometer
* Photometric redshift
* Photometry (optics)
* Photomixing
* Photomultiplier
* Photon
* Photon-in-photon-out
* Photon-intermediate direct energy conversion
* Photon Doppler velocimetry
* Photon Factory
* Photon diffusion
* Photon entanglement
* Photon epoch
* Photon gas
* Photon induced electric field poling
* Photon noise
* Photon polarization
* Photon sphere
* Photonic-crystal fiber
* Photonic crystal
* Photonic integrated circuit
* Photonic metamaterial
* Photonics
* Photonics Letters of Poland
* Photonics Society of Poland
* Photonics and Nanostructures
* Photonics and Nanostructures: Fundamentals and Applications
* Photophoresis
* Photorefractive effect
* Photoresist
* Photosensitive glass
* Photosensitizer
* Photothermal effect
* Photothermal optical microscopy
* Photothermal spectroscopy
* Photovoltaic effect
* Photovoltaics
* Phugoid
* Phun
* Phyllis S. Freier
* Phys.Org
* Physica (journal)
* Physica A
* Physica B
* Physica C
* Physica D
* Physica E
* Physica Scripta
* Physica Status Solidi
* Physica Status Solidi A
* Physica Status Solidi B
* Physica Status Solidi C
* Physica Status Solidi RRL
* Physical Biology
* Physical Chemistry Chemical Physics
* Physical Review
* Physical Review A
* Physical Review A: General Physics
* Physical Review E
* Physical Review Focus
* Physical Review Letters
* Physical Science Study Committee
* Physical Society of Japan
* Physical Society of London
* Physical acoustics
* Physical body
* Physical constant
* Physical cosmology
* Physical geodesy
* Physical law
* Physical objects
* Physical optics
* Physical paradox
* Physical phenomenon
* Physical property
* Physical quantity
* Physical Review E: Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics
* Physical strength
* Physical substance
* Physical system
* Physical theories modified by general relativity
* Physicist
* Physicist and Christian
* Physics
* PhysicsWeb
* Physics (American Physical Society journal)
* Physics Abstracts
* Physics Abstracts. Science Abstracts. Series A
* Physics Abstracts - Series A
* Physics Abstracts - Series A: Science Abstracts
* Physics Abstracts Series A
* Physics Analysis Workstation
* Physics Education
* Physics Letters
* Physics Letters A
* Physics Letters B
* Physics Reports
* Physics Today
* Physics and Astronomy Classification Scheme
* Physics and Chemistry of Liquids
* Physics and Chemistry of Minerals
* Physics and Star Trek
* Physics and engineering explorations
* Physics beyond the Standard Model
* Physics education
* Physics envy
* Physics equations
* Physics in Medicine and Biology
* Physics in medieval Islam
* Physics of Fluids
* Physics of Life Reviews
* Physics of Plasmas
* Physics of computation
* Physics of firearms
* Physics of glass
* Physics of skiing
* Physics of the Impossible
* Physics of the Solid State
* Physics Today
* Physikalisch-Technische Bundesanstalt
* Physikalische Blätter
* Physikalische Zeitschrift
* Pi Josephson junction
* Piara Singh Gill
* Picard horn
* Picarin
* Picotechnology
* Picture (string theory)
* Piermaria Oddone
* Piero Giorgio Bordoni
* Pierre-Gilles de Gennes
* Pierre-Michel Duffieux
* Pierre-Simon Laplace
* Pierre Aigrain
* Pierre Angénieux
* Pierre Auger Observatory
* Pierre Bertholon de Saint-Lazare
* Pierre Bouguer
* Pierre Curie
* Pierre Goldschmidt
* Pierre Henri Hugoniot
* Pierre Hohenberg
* Pierre Louis Dulong
* Pierre Louis Maupertuis
* Pierre Perrault (scientist)
* Pierre Polinière
* Pierre Prévost
* Pierre Ramond
* Pierre Victor Auger
* Pierre Weiss
* Pierson–Moskowitz spectrum
* Pieter Kok
* Pieter Rijke
* Pieter Zeeman
* Pieter van Musschenbroek
* Piezoelectric coefficient
* Piezoelectricity
* Piezoresistive effect
* Piezoresponse force microscopy
* Pilot wave
* Pin group
* Pinch (magnetic fusion)
* Pinch (plasma physics)
* Pincushion distortion
* Pink noise
* Pinning force
* Piola-Kirchhoff stress tensor
* Pion
* Pion decay constant
* Pioneer anomaly
* Pionium
* Pipe flow
* Pipe network analysis
* Pis'ma v Astronomicheskii Zhurnal
* Piston (optics)
* Pit (nuclear weapon)
* Pitch-up
* Pitch drop experiment
* Pitching moment
* Pitot tube
* Piyare Jain
* Planar array radar
* Planar laser-induced fluorescence
* Planck's law
* Planck (spacecraft)
* Planck angular frequency
* Planck charge
* Planck constant
* Planck current
* Planck density
* Planck energy
* Planck epoch
* Planck force
* Planck impedance
* Planck length
* Planck mass
* Planck matter
* Planck momentum
* Planck particle
* Planck postulate
* Planck power
* Planck pressure
* Planck radiation
* Planck scale
* Planck temperature
* Planck time
* Planck units
* Planck voltage
* Plane mirror
* Plane of incidence
* Plane of reference
* Plane wave expansion method
* PlanetPhysics
* Planetarium hypothesis
* Planetary and Space Science
* Planetary nebula
* Planetary nebula luminosity function
* Planets beyond Neptune
* Plasma (physics)
* Plasma Physics Laboratory (Saskatchewan)
* Plasma Science Society of India
* Plasma Sources Science and Technology
* Plasma acceleration
* Plasma channel
* Plasma cleaning
* Plasma containment
* Plasma cosmology
* Plasma diagnostics
* Plasma facing material
* Plasma fountain
* Plasma gasification
* Plasma globe
* Plasma lamp
* Plasma modeling
* Plasma oscillation
* Plasma parameter
* Plasma parameters
* Plasma propulsion engine
* Plasma recombination
* Plasma scaling
* Plasma source
* Plasma speaker
* Plasma stability
* Plasma stealth
* Plasma torch
* Plasma weapon
* Plasma window
* Plasmaron
* Plasmasphere
* Plasmat lens
* Plasmoid
* Plasmon
* Plasmonic cover
* Plasmonic metamaterials
* Plasmonic solar cell
* Plastic-clad silica fiber
* Plastic Fantastic: How the Biggest Fraud in Physics Shook the Scientific World
* Plastic bending
* Plastic deformation in solids
* Plastic magnet
* Plastic moment
* Plasticity (physics)
* Plastometer
* Plate tectonics
* Plateau–Rayleigh instability
* Platinum Metals Review
* Plato
* Platteville Atmospheric Observatory
* Plebanski action
* Plekton
* Pleuger rudder
* Plug flow
* Plum pudding model
* Plume (hydrodynamics)
* Plummer model
* Plus minus method
* Plutonium
* Plutonium(IV) oxide
* Plutonium-238
* Plutonium-239
* Pneumatic barrier
* Pneumatic circuit
* Pneumatic cylinder
* Pneumatic flow control
* Pneumatic motor
* Pockels effect
* Pohlmeyer charge
* Poincaré Seminar
* Poincaré Seminars
* Poincaré group
* Poincaré map
* Poincaré recurrence theorem
* Poincaré–Bendixson theorem
* Poincaré–Lindstedt method
* Poinsot's ellipsoid
* Point charge
* Point mass
* Point particle
* Point source
* Point source (light)
* Point spread function
* Poise
* Poisson's equation
* Poisson's ratio
* Poisson bracket
* Poisson–Boltzmann equation
* Pol Duwez
* Pol Swings
* Polar cyclone
* Polar mesosphere summer echoes
* Polar moment of inertia
* Polar orbit
* Polar vortex
* Polar wander
* Polar wind
* Polarimetry
* Polariton
* Polariton superfluid
* Polarity (disambiguation)
* Polarizability
* Polarizable vacuum
* Polarization-division multiplexing
* Polarization (waves)
* Polarization density
* Polarization in astronomy
* Polarization mode dispersion
* Polarization spectroscopy
* Polarized target
* Polarizer
* Polaroid (polarizer)
* Polaron
* Polhode
* Polyakov action
* Polyamorphism
* Polychromatic
* Polychromator
* Polykarp Kusch
* Polymer Bulletin
* Polymer physics
* Polymer science
* Polymer solar cell
* Polymeric liquid crystal
* Polyphase coil
* Polyphase system
* Polytrope
* Polytropic process
* Polywater
* Polywell
* Pomeranchuk Prize
* Pomeron
* Ponderomotive energy
* Ponderomotive force
* Pons-Fleischmann experiment
* Pontecorvo–Maki–Nakagawa–Sakata matrix
* Poole–Frenkel effect
* Pople notation
* Population I Cepheid
* Population I Cepheids
* Population inversion
* Poromechanics
* Pororoca
* Portevin–Le Chatelier effect
* Posidonius
* Position and momentum space
* Position operator
* Position space
* Positive displacement meter
* Positive energy theorem
* Positive pressure
* Positron
* Positron emission
* Positron emission tomography
* Positronium
* Positronium hydride
* Post-Hartree–Fock
* Post-Newtonian expansion
* Post Office Box (electricity)
* Postulates of special relativity
* Potassium titanyl phosphate
* Potential
* Potential difference
* Potential energy
* Potential energy surface
* Potential flow
* Potential gradient
* Potential temperature
* Potential theory
* Potential vorticity
* Potential well
* Potentiometric surface
* Potsdam Denkschrift
* Potts model
* Poul la Cour
* Pound–Rebka experiment
* Powder-in-tube
* Powder diffraction
* Power-law fluid
* Power-law index profile
* Power-to-weight ratio
* Power (physics)
* Power density
* Power history
* Power number
* Power optimizer
* Powered hang glider
* Poynting's theorem
* Poynting vector
* Pp-wave spacetime
* Prabhakar Misra
* Prabhu Lal Bhatnagar
* Pran Nath
* Prandtl-Glauert method
* Prandtl number
* Prandtl–Glauert singularity
* Prandtl–Glauert transformation
* Prandtl–Meyer expansion fan
* Prandtl–Meyer function
* Praveen Chaudhari
* Pre-echo
* Pre-main-sequence star
* Precession
* Precision Array for Probing the Epoch of Reionization
* Precision tests of QED
* Predhiman Krishan Kaw
* Predictability
* Predrag Cvitanović
* Preferential concentration
* Preferred frame
* Pregeometry (physics)
* Premelting
* Preon
* Preon star
* Present
* Presentism (philosophy of time)
* Pressure
* Pressure-correction method
* Pressure-fed engine (rocket)
* Pressure-gradient force
* Pressure-sensitive paint
* Pressure coefficient
* Pressure drop
* Pressure exchanger
* Pressure experiment
* Pressure head
* Pressure measurement
* Pressure volume diagram
* Press–Schechter formalism
* Primakoff effect
* Primary field
* Primary flow element
* Primitive cell
* Primitive equations
* Primon gas
* Primordial black hole
* Primordial isocurvature baryon model
* Primordial nuclide
* Primum Mobile
* Princeton Plasma Physics Laboratory
* Princeton ocean model
* Principal axis (mechanics)
* Principal quantum number
* Principle of Calorimetry
* Principle of corresponding states
* Principle of inertia (physics)
* Principle of least action
* Principle of locality
* Principle of material objectivity
* Principle of maximum entropy
* Principle of maximum work
* Principle of minimum energy
* Principle of relativity
* Principles of Quantum Mechanics
* Prism (optics)
* Prism compressor
* Probability amplitude
* Probability current
* Probing Lensing Anomalies Network
* Proca action
* Proceedings of SPIE
* Proceedings of the Physical Society
* Proceedings of the USSR Academy of Sciences
* Process function
* Prodicus
* Prof. Eleftheriades
* Professor Eleftheriades
* Progress in Electromagnetics Research
* Progress in Materials Science
* Progress in Optics
* Progress in Physics
* Progress of Theoretical Physics
* Progress of Theoretical Physics Supplement
* Project Mohole
* Project Tuva
* Projectile motion
* Projection method (fluid dynamics)
* Projective superspace
* Prompt critical
* Prompt gamma neutron activation analysis
* Prompt neutron
* Prony equation
* Propagation constant
* Propagation delay
* Propagator
* Propellant mass fraction
* Proper acceleration
* Proper frame
* Proper length
* Proper motion
* Proper orbital elements
* Proper time
* Proper velocity
* Proportional counter
* Propulsion
* Propulsive efficiency
* Prosper-René Blondlot
* Protogalaxy
* Proton
* Proton-to-electron mass ratio
* Proton Synchrotron
* Proton Synchrotron Booster
* Proton decay
* Proton emission
* Proton spin crisis
* Protonium
* Proton–gyromagnetic ratio
* Proton–proton chain reaction
* Protoplanetary nebula
* Protostar
* Proximity effect (atomic physics)
* Proximity effect (audio)
* Przybylski's Star
* Pseudo-Anosov map
* Pseudo-Euclidean space
* Pseudo-Goldstone boson
* Pseudo-Riemannian manifold
* Pseudo Stirling cycle
* Pseudogap
* Pseudophakic photic phenomena
* Pseudopotential
* Pseudorapidity
* Pseudoscalar
* Pseudoscalar meson
* Pseudotensor
* Pseudovector
* Pseudovector meson
* Psi meson
* Psychic determinism
* Psychoacoustics
* Psychrometrics
* Ptychography
* Pucadyil Ittoop John
* Pulsar
* Pulsar kicks
* Pulsatile flow
* Pulse (physics)
* Pulse forming network
* Pulse height analyzer
* Pulsed EPR
* Pulsed field gradient
* Pulsed laser deposition
* Pulsed power
* Pulsometer steam pump
* Pump
* Pumplinx
* Purcell effect
* Purdue University Reactor Number One
* Pure bending
* Pure gauge
* Pure shear
* Pure spinor
* Pure state
* Purity (gas)
* Purity (quantum mechanics)
* Pwpaw
* Pyotr Kapitsa
* Pyotr Lebedev
* Pyotr Valentinovich Trusov
* Pyranometer
* Pyrgeometer
* Pyroelectric crystal
* Pyroelectric fusion
* Pyroelectricity
* Pyrometer
* Pyrometry
* Pythagoras
* Pythagorean hammers
* Pål Brekke
* Péclet number
* P–n junction