quantum acoustics
31Wave — A wave is a disturbance that propagates through space and time, usually with transference of energy. While a mechanical wave exists in a medium (which on deformation is capable of producing elastic restoring forces), waves of electromagnetic… …
32Superposition principle — In physics and systems theory, the superposition principle, also known as superposition property, states that, for all linear systems,: The net response at a given place and time caused by two or more stimuli is the sum of the responses which… …
33Acoustic metric — In mathematical physics, a metric describes the arrangement of relative distances within a surface or volume, usually measured by signals passing through the region – essentially describing the intrinsic geometry of the region. An acoustic metric …
34Defining equation (physics) — For common nomenclature of base quantities used in this article, see Physical quantity. For 4 vector modifications used in relativity, see Four vector. Very often defining equations are in the form of a constitutive equation, since parameters of… …
35Copley Medal — The Copley Medal awarded to Mendeleev in 1905 …
36Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… …
37Fluid dynamics — Continuum mechanics …
38General relativity — For a generally accessible and less technical introduction to the topic, see Introduction to general relativity. General relativity Introduction Mathematical formulation Resources …
39Helmholtz equation — The Helmholtz equation, named for Hermann von Helmholtz, is the elliptic partial differential equation:( abla^2 + k^2) A = 0where abla^2 is the Laplacian, k is a constant, and the unknown function A=A(x, y, z) is defined on n dimensional… …
40Coherence (physics) — In physics, coherence is a property of waves that enables stationary (i.e. temporally and spatially constant) interference. More generally, coherence describes all properties of the correlation between physical quantities of a wave. When… …
