Tags
A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.
The study of the presence and flow of electric charge. Charges, currents, fields, potentials.
4052 questions
The photon is the quantum of the electromagnetic four-potential, and therefore the massless bosonic particle associated with the electromagnetic force, commonly also called the "particle of light". Us…
4037 questions
For questions about design, process, data, or analysis of experiments and observations.
3875 questions
A complex scalar field that describes a quantum mechanical system. The square of the modulus of the wave function gives the probability of the system to be found in a particular state. DO NOT USE THIS…
3819 questions
for questions relating to pressure, in the physical sciences, the perpendicular force per unit area, or the stress at a point within a confined fluid.
3663 questions
In introductory mechanics, the momentum of a particle is its mass times its velocity. In electrodynamics, the momentum of a field is proportional to the cross-product of the electric field with the ma…
3642 questions
The variables used in general relativity to describe the shape of spacetime. If your question is about metric units, use the tag "units", and/or "si-units" if it is about the SI system specifically.
3560 questions
Solid-state physics studies how macroscopic properties of solids (mechanical, electrical, optical, etc.) result from their microscopic structure. It usually deals with the scale where quantum properti…
3532 questions
It's the physical property that indicates the degree/intensity of heat present in a substance or an object. It can be expressed and measured according to various scales.
3474 questions
Quantum information is the study of the informational content of quantum states. The most common object of study is the "qubit", the information in a two-state quantum system such as spin-1/2 or photo…
3444 questions
A fundamental property of matter which causes it to experience electromagnetic forces.
3415 questions
The law of conservation of energy, which states that the amount of energy in a system is constant. For questions about Earth's environment, see the climate-science tag instead.
3409 questions
A measure of the rate at which electric charge is transported (especially through a circuit), it has units of charge/time.
3365 questions
Negatively charged particle with spin 1/2. A component of mundane terrestrial matter, and part of all neutral atoms and molecules. It has a mass about 1/1800 that of a proton. Its antiparticle is the…
3353 questions
Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts.
3330 questions
The property of an object that determines how much it responds to a force in Newtonian mechanics, and how much it interacts with gravity in the Newtonian framework. Mass also refers to the intrinsic e…
3300 questions
Symmetries play a big role in modern physics and have been a source of powerful tools and techniques for understanding theories and their dynamics. We say that something is symmetric if there is some …
3272 questions
The statement that a property of a system does not change if the system is isolated.
3139 questions
Scalar and vector potentials in electromagnetism. The scalar potential is potential energy per unit charge. For potential energy, use the [potential-energy] tag.
3131 questions
A set of numbers used to quantify location in space.
3107 questions
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus and t…
3070 questions
The rate of change of velocity of a body per unit of time.
3062 questions
The product of the force on an object and the displacement the object undergoes along the direction of the force.
3048 questions
For questions where the dynamical variables are fields, that is, functions of several variables (typically, one time coordinate and several space coordinates). Comprises both classical field theory an…
3035 questions
An important extensive property of all systems in thermodynamics, statistical mechanics, and information theory, quantifying their disorder (randomness), i.e., our lack of information about them. It …
2987 questions
Partial differential equation which describes the time evolution of the wavefunction of a quantum system. It is one of the first and most fundamental equations of quantum mechanics.
2937 questions
The speed of light is a fundamental universal constant that marks the maximum speed at which energy and information can propagate. Its value is $299792458\frac{\mathrm{m}}{\mathrm{s}}$.
2829 questions
Fundamental characteristic property of particles which together with orbital angular momentum acts as the generator of rotations and which doesn't have a classical equivalent but is sometimes compared…
2815 questions
Acoustics is the interdisciplinary science that deals with the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound. Applications of acoust…
2784 questions
The application of physical theory to celestial systems such as stars, planets, galaxies, supernovae, and black holes. Astrophysics proper is concerned with explaining phenomena more so than making ob…
2763 questions
to electrical resistance and resistors. DO NOT USE THIS TAG for non-electrical resistance.
2758 questions
The resistance a surface or object encounters when moving over another.
2743 questions
A class of theories that attempt to explain all existing particles (including force carriers) as vibrational modes of extended objects, such as the 1-dimensional fundamental string. PLEASE DO NOT USE …
2720 questions
A specific reference frame that describes its coordinates in a manner that does not depend on time and is isotropic.
2673 questions
Potential energy is the energy of a body or a system due to the position of the body or the arrangement of the particles of the system.
2650 questions
Geometric object with magnitude (length) and direction.
2600 questions