# 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:
 dark-matter× 301 Matter not observed directly but inferred to exist based upon its gravitational effects maxwell-equations× 299 The four fundamental fundamental equations of electromagnetism. mathematics× 299 just because your question involves math! If your question is on simplification of a mathematical expression, please ask it at math.stackexchange.com The mathematics tag covers non… interference× 298 air× 294 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… quantum-chromodynamics× 293 the quantum field theory believed to describe the strong nuclear force. sun× 292 an almost perfectly symmetric yellow dwarf star [spectral class G2V] which is at the center of our Solar System. tensors× 292 coordinate-systems× 292 quantify location in space. geometry× 292 To be used for questions on geometry closely pertaining to physics. Includes differential geometry and euclidean geometry. variational-principle× 291 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… stars× 291 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… notation× 289 drag× 289 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. power× 288 The time rate of change of energy lie-algebra× 286 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… gauss-law× 285 A law in Classical Electromagnetism and Newtonian Gravity. feynman-diagram× 285 conventions× 285 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. mass-energy× 284 dimensions× 283 for dimensions of a manifold, typically the space-time. DO NOT USE THIS TAG for dimension of a physical quantity. polarization× 278 Polarization characterizes the oscillations in time the electromagnetic field is doing in the plane perpendicular to the propagation direction of a wave quantum-computer× 277 solar-system× 276 The Sun plus the collection of bodies in orbit around the Sun such as planets, dwarf planets, moons, asteroids, comets, etc. quantum-optics× 275 A research field within general optical physics concerned with light and its material interaction: where light is modelled by full quantum mechanical description. fermions× 270 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 … antimatter× 269 Analogous to matter, but with charge of the particles opposite to their ordinary matter counterparts. rotational-kinematics× 267 A tag for questions about rotational motion, including angular velocity and angular acceleration. geometric-optics× 264 The subfield of optics in which light propagation is approximated in terms of rays. It mainly includes reflection and refraction on surfaces. diffraction× 263 phase-transition× 262 speed× 260 the magnitude of velocity. integration× 259 For questions about problems related to physics that involve evaluating integrals. Purely mathematical questions should be asked at math.SE. representation-theory× 258 hamiltonian× 256 The central term in the hamiltonian formalism. Can be interpreted as an energy input, or "true" energy. neutrinos× 255 light, uncharged leptons. The neutrino tag should be applied to question relating to neutrino properties or interactions involving neutrinos.