# 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.

 Type to find tags:
 lie-algebra× 249 A vector space $\mathfrak{g}$ over some field $F$ and kitted with a bilinear, antisymmetric and Jacobi-identity-fulfilling product ("Lie Bracket" or "commutator"). In physics, most often arises as the… dark-matter× 248 Matter not observed directly but inferred to exist based upon its gravitational effects spring× 247 An object such as a metal coil or air-filled tube which provides a force opposing the direction of deformation. spectroscopy× 247 the practice of separating a signal by frequency (or sometimes energy or momentum) and analyzing the resulting spectrum. dimensions× 245 for dimensions of a manifold, typically the space-time. DO NOT USE THIS TAG for dimension of a physical quantity. maxwell-equations× 245 The four fundamental fundamental equations of electromagnetism. coordinate-systems× 244 quantify location in space. air× 244 a layer of gases that surround it, permitting life and protecting life by absorbing ultraviolet solar radiation, warming the surface by retaining the heat and mitigating the temp… notation× 243 ideal-gas× 243 A gas that behaves as randomly moving, non-interacting molecules. This allows a simplified equation of state. stars× 242 astronomical bodies that are (usually) mainly composed of Hydrogen, Helium, and Lithium. They are massive enough that their gravity compresses the matter to the point where nuclear fusion oc… rotation× 241 Circular motion about a central point or axis geometry× 240 To be used for questions on geometry closely pertaining to physics. Includes differential geometry and euclidean geometry. variational-principle× 239 any of several principles that find the physical trajectory of a system by minimizing or maximizing some value computed over the proposed path (for instance geometric optics can be reproduced by insis… power× 235 The time rate of change of energy polarization× 235 Polarization characterizes the oscillations in time the electromagnetic field is doing in the plane perpendicular to the propagation direction of a wave quantum-computer× 233 solar-system× 233 The Sun plus the collection of bodies in orbit around the Sun such as planets, dwarf planets, moons, asteroids, comets, etc. quantum-optics× 231 A research field within general optical physics concerned with light and its material interaction: where light is modelled by full quantum mechanical description. drag× 231 The force on a body resulting from it's motion through a fluid (gas or liquid). This force is directly opposed to the direction of travel. interference× 229 conventions× 228 a set of agreed, stipulated, or generally accepted norms. It typically helps common efficiency or understanding but is not required, as opposed to a strict standard or protocol. fermions× 227 particles with an intrinsic angular momentum (i.e. spin) equal to a "half integer" number of fundamental units: $\frac{(2n+1)}{2} \hbar$ for integer $n$. Fermions are required to be in a … feynman-diagram× 226 gauss-law× 225 A law in Classical Electromagnetism and Newtonian Gravity. mass-energy× 223 representation-theory× 223 integration× 220 antimatter× 220 Analogous to matter, but with charge of the particles opposite to their ordinary matter counterparts. neutrinos× 216 light, uncharged leptons. The neutrino tag should be applied to question relating to neutrino properties or interactions involving neutrinos. phase-transition× 213 speed× 212 the magnitude of velocity. hamiltonian× 212 The central term in the hamiltonian formalism. Can be interpreted as an energy input, or "true" energy. geometric-optics× 210 The subfield of optics in which light propagation is approximated in terms of rays. It mainly includes reflection and refraction on surfaces. symmetry-breaking× 210 diffraction× 208