Concepts in physics

Electromagnetic or Magnetic induction is the production of an electromotive force or voltage across an electrical conductor due to its dynamic interaction with a magnetic field.

In classical statistical mechanics, the equipartition theorem is a general formula that relates the temperature of a system with its average energies.

In physics, a symmetry of a physical system is a physical or mathematical feature of the system (observed or intrinsic) that is preserved or remains unchanged under some transformation.

Supercooling, also known as undercooling, is the process of lowering the temperature of a liquid or a gas below its freezing point without it becoming a solid.

A physical law or scientific law is a theoretical statement "inferred from particular facts, applicable to a defined group or class of phenomena, and expressible by the statement that a particular phenomenon always occurs if certain conditions be present.

In mathematics, a Green's function is the impulse response of an inhomogeneous differential equation defined on a domain, with specified initial conditions or boundary conditions.

Plasma (from Greek πλάσμα, "anything formed") is one of the four fundamental states of matter, the others being solid, liquid, and gas.

A thought experiment considers some hypothesis, theory, or principle for the purpose of thinking through its consequences.

In the physical sciences, a phase is a region of space (a thermodynamic system), throughout which all physical properties of a material are essentially uniform.

A scalar in physics is a physical quantity that can be described by a single element of a number field such as a real number, often accompanied by units of measurement.

In physics, a field is a physical quantity, typically a number or tensor, that has a value for each point in space and time.

In the theory of relativity, time dilation is a difference of elapsed time between two events as measured by observers either moving relative to each other or differently situated from a gravitational mass or masses.

The Arrow of Time, or Time's Arrow, is a concept developed in 1927 by the British astronomer Arthur Eddington involving the "one-way direction" or "asymmetry" of time.

In mathematics and theoretical physics, an invariant is a property of a system which remains unchanged under some transformation.

In physics, heat is energy that spontaneously passes between a system and its surroundings in some way other than through work or the transfer of matter.

The second law of thermodynamics states that the total entropy of an isolated system always increases over time, or remains constant in ideal cases where the system is in a steady state or undergoing a reversible process.

An electromagnet is a type of magnet in which the magnetic field is produced by an electric current.

The first law of thermodynamics is a version of the law of conservation of energy, adapted for thermodynamic systems.

Cherenkov radiation, also known as Vavilov–Cherenkov radiation, is electromagnetic radiation emitted when a charged particle (such as an electron) passes through a dielectric medium at a speed greater than the phase velocity of light in that medium.

The kinetic theory describe a gas as a large number of submicroscopic particles (atoms or molecules), all of which are in constant rapid motion that has randomness arising from their many collisions with each other and with the walls of the container.

In physics, a conservation law states that a particular measurable property of an isolated physical system does not change as the system evolves over time.

In nuclear physics and nuclear chemistry, a nuclear reaction is semantically considered to be the process in which two nuclei, or else a nucleus of an atom and a subatomic particle (such as a proton, neutron, or high energy electron) from outside the atom, collide to produce one or more nuclides that are different from the nuclide(s) that began the process.

In mathematics, a partial differential equation (PDE) is a differential equation that contains unknown multivariable functions and their partial derivatives.

A Majorana fermion (/maɪəˈrɒnə ˈfɛərmiːɒn/), also referred to as a Majorana particle, is a fermion that is its own antiparticle.

Superfluidity is the characteristic property of a fluid with zero viscosity which therefore flows without loss of kinetic energy.

In particle physics, the weak interaction (the weak force or weak nuclear force) is one of the four known fundamental interactions of nature, alongside the strong interaction, electromagnetism, and gravitation.

In quantum mechanics, a parity transformation (also called parity inversion) is the flip in the sign of one spatial coordinate.

The wave equation is an important second-order linear partial differential equation for the description of waves—as they occur in physics—such as sound waves, light waves and water waves.

The Cauchy momentum equation is a vector partial differential equation put forth by Cauchy that describes the non-relativistic momentum transport in any continuum.

In fluid dynamics, the Euler equations are a set of quasilinear hyperbolic equations governing adiabatic and inviscid flow.

In numerous fields of study, the component of instability within a system is generally characterized by some of the outputs or internal states growing without bounds.

Noether's (first) theorem states that every differentiable symmetry of the action of a physical system has a corresponding conservation law.

In solid-state physics, the work function (sometimes spelled workfunction) is the minimum thermodynamic work (i.e. energy) needed to remove an electron from a solid to a point in the vacuum immediately outside the solid surface.

A shear stress, denoted τ (Greek: tau), is defined as the component of stress coplanar with a material cross section.

The cross section is an effective area that quantifies the intrinsic likelihood of a scattering event when an incident beam strikes a target object, made of discrete particles.

Newton's laws of motion are three physical laws that, together, laid the foundation for classical mechanics.

The Standard Model of particle physics is a theory concerning the electromagnetic, weak, and strong nuclear interactions, as well as classifying all the subatomic particles known.

Quantum numbers describe values of conserved quantities in the dynamics of a quantum system.

Specific gravity is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.

Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material.

In particle physics, a fermion (a name coined by Paul Dirac from the surname of Enrico Fermi) is any particle characterized by Fermi–Dirac statistics.

In thermodynamics, the volume of a system is an important extensive parameter for describing its thermodynamic state.

Entropy is a measure of the energy of a system that is unavailable for doing useful work.

In physics, quantization is the process of transition from a classical understanding of physical phenomena to a newer understanding known as quantum mechanics.

A spectrum (plural spectra or spectrums) is a condition that is not limited to a specific set of values but can vary infinitely within a continuum.

Thermal conduction is the transfer of heat (internal energy) by microscopic collisions of particles and movement of electrons within a body.

In physics, spacetime is any mathematical model that combines space and time into a single interwoven continuum.

In physics (particularly in electromagnetism) the Lorentz force is the combination of electric and magnetic force on a point charge due to electromagnetic fields.

A physical constant, sometimes fundamental physical constant, is a physical quantity that is generally believed to be both universal in nature and having constant value in time.

Linearity is the property of a mathematical relationship or function which means that it can be graphically represented as a straight line, that is, that one quantity is simply proportional to another.

In thermodynamics, a heat engine is a system that converts heat or thermal energy—and chemical energy—to mechanical energy, which can then be used to do mechanical work.

In probability theory, a probability density function (PDF), or density of a continuous random variable, is a function that describes the relative likelihood for this random variable to take on a given value.

The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics.

Scale of temperature is a way to measure temperature quantitatively.

The quantum electrodynamic vacuum or QED vacuum is the field-theoretic vacuum of quantum electrodynamics.

In particle physics, the strong interaction is the mechanism responsible for the strong nuclear force (also called the strong force, nuclear strong force), and is one of the four known fundamental interactions, the others are electromagnetism, the weak interaction and gravitation.

Vacuum is space void of matter.

In statistical mechanics, Maxwell–Boltzmann statistics describes the average distribution of non-interacting material particles over various energy states in thermal equilibrium, and is applicable when the temperature is high enough or the particle density is low enough to render quantum effects negligible.

In physics, the Navier–Stokes equations /nævˈjeɪ stoʊks/, named after Claude-Louis Navier and George Gabriel Stokes, describe the motion of viscous fluid substances.

Photon polarization is the quantum mechanical description of the classical polarized sinusoidal plane electromagnetic wave.

In physics, the term observer effect refers to changes that the act of observation will make on a phenomenon being observed.

The path integral formulation of quantum mechanics is a description of quantum theory which generalizes the action principle of classical mechanics.

Paramagnetism is a form of magnetism whereby certain materials are attracted by an externally applied magnetic field, and form internal, induced magnetic fields in the direction of the applied magnetic field.

Tensors are geometric objects that describe linear relations between geometric vectors, scalars, and other tensors.

In thermodynamics, the Gibbs free energy (IUPAC recommended name: Gibbs energy or Gibbs function; also known as free enthalpy to distinguish it from Helmholtz free energy) is a thermodynamic potential that can be used to calculate the maximum or reversible work that may be performed by a thermodynamic system at a constant temperature and pressure (isothermal, isobaric).

The term observer has a number of non-equivalent uses in science.

The covariant formulation of classical electromagnetism refers to ways of writing the laws of classical electromagnetism (in particular, Maxwell's equations and the Lorentz force) in a form that is manifestly invariant under Lorentz transformations, in the formalism of special relativity using rectilinear inertial coordinate systems.

The quantum potential or quantum potentiality is a central concept of the de Broglie–Bohm formulation of quantum mechanics, introduced by David Bohm in 1952.

The intent of this article is to highlight the important points of the derivation of the Navier–Stokes equations as well as the application and formulation for different families of fluids.

The mathematics of general relativity are complex.