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:
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Object moving through space due to the exertion of a force.
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a quantum field theory that is invariant under conformal transformations. In 2D, the infinite-dimensional algebra of local conformal transformations normally permits …
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the transmission of current with no resistive losses, and is one of the most active areas of condensed matter physics research.
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The tendency of a force to rotate an object about an arbitrary axis.
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The double slit experiment involves passing light through two parallel slits to demonstrate that the light from one slit interferes with that from the other.
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the unit of measurement for electronic potential, from one point location to another.
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standards of measurement used for different types of quantities.
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Change in the direction of propagation of a wave when its transmitting medium changes.
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for questions relating to what, if anything, the quantum mechanical formalism and experimental results say about the way the world works.
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A nucleus made of protons and neutrons surrounded by a cloud of electrons equal in number to the protons.
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The historical development of physics concepts: who did what and when.
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The study of the composition or dynamics of the gaseous layers around planets, often applied to questions on Earth's atmosphere but can be applicable to all planets & moons in the solar system.
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Celestial body that orbits following an elliptical path around a star or stellar remnant.
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The temperature-dependant emission of electromagnetic waves. Combine this tag with [tag:thermodynamics] for a macroscopic view or [tag:quantum-mechanics] for a microscopic explanation.
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Subdiscipline of theoretical physics which consists in the study of physics problems using numerical algorithms. PLEASE NOTE that questions about computational methods and/or programming are OFF-TOPIC…
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Use this for questions pertaining to curvature of manifolds. Does not need to be specific to general relativity, but also for curvature of e.g. a [tag:calabi-yau] manifold.
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A unitary linear operator which resolves a function on $\mathbb{R}^N$ into a linear superposition of "plane wave functions". Most often used in physics for calcalating the response of a time shift inv…
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A region of space devoid of any fluid molecules resulting in a zero pressure in ideal cases. In practice, even space has a small but finite number of molecules. In QFT, it signifies the ground state d…
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for questions seeking a single specific paper or a short, non-open-ended list of references, like "What paper first discovered X?", "Where can I find the original derivation of X?", or "W…
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for questions about the quantum mechanical measurement problem, such as e.g. the wavefunction collapse/decoherence. DO NOT USE THIS TAG for non-quantum measurements.
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"Faster-than-light", also known as superluminal velocities, refers to any sort of travel at a speed greater than the speed of light. Prohibited in mainstream physics due to the Special theory of …
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Study of macroscopic and microscopic phenomena in chemical systems in terms of physical laws and concepts [thermodynamics, statistical mechanics, kinetic theory, quantum mechanics...].
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Path integral formulation (Due to Feynman) is a major formulation of Quantum Mechanics along with Matrix mechanics (Due to Heisenberg and Pauli), Wave Mechanics (Due to Schrodinger), and Variational M…
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The four fundamental fundamental equations of electromagnetism.
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the rate of repetitive aspect in the amplitude over a given dimension.
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An object such as a metal coil or air-filled tube which provides a force opposing the direction of deformation.
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For questions about probability, probability theory, probability distributions, expected values and related matters. Purely mathematical questions should be asked on Math.SE.
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Circular motion about a central point or axis
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A gas that behaves as randomly moving, non-interacting molecules. This allows a simplified equation of state.
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is used in situations where the question is either about how some term or concept is define or where the validity of an answer depends on a subtle definition of some term or concept…
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questions concerning measurements, experiments, and activities that demonstrate physics and are safe to do at home, require at most one tool or ingredient not readily available, and can be interpreted…
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the practice of separating a signal by frequency (or sometimes energy or momentum) and analyzing the resulting spectrum.
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the quantum field theory believed to describe the strong nuclear force.