When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Envelope (mathematics) - Wikipedia

    en.wikipedia.org/wiki/Envelope_(mathematics)

    In geometry, an envelope of a planar family of curves is a curve that is tangent to each member of the family at some point, and these points of tangency together form the whole envelope. Classically, a point on the envelope can be thought of as the intersection of two " infinitesimally adjacent" curves, meaning the limit of intersections of ...

  3. Back-of-the-envelope calculation - Wikipedia

    en.wikipedia.org/wiki/Back-of-the-envelope...

    A back-of-the-envelope calculation is a rough calculation, typically jotted down on any available scrap of paper such as an envelope. It is more than a guess but less than an accurate calculation or mathematical proof. The defining characteristic of back-of-the-envelope calculations is the use of simplified assumptions.

  4. Envelope theorem - Wikipedia

    en.wikipedia.org/wiki/Envelope_theorem

    In mathematics and economics, the envelope theorem is a major result about the differentiability properties of the value function of a parameterized optimization problem. [1] As we change parameters of the objective, the envelope theorem shows that, in a certain sense, changes in the optimizer of the objective do not contribute to the change in ...

  5. Moreau envelope - Wikipedia

    en.wikipedia.org/wiki/Moreau_envelope

    By Hopf–Lax formula, the Moreau envelope is a viscosity solution to a Hamilton–Jacobi equation. [3] Stanley Osher and co-authors used this property and Cole–Hopf transformation to derive an algorithm to compute approximations to the proximal operator of a function.

  6. Envelope (waves) - Wikipedia

    en.wikipedia.org/wiki/Envelope_(waves)

    In physics and engineering, the envelope of an oscillating signal is a smooth curve outlining its extremes. [1] The envelope thus generalizes the concept of a constant amplitude into an instantaneous amplitude. The figure illustrates a modulated sine wave varying between an upper envelope and a lower envelope. The envelope function may be a ...

  7. Lower envelope - Wikipedia

    en.wikipedia.org/wiki/Lower_envelope

    In mathematics, the lower envelope or pointwise minimum of a finite set of functions is the pointwise minimum of the functions, the function whose value at every point is the minimum of the values of the functions in the given set.

  8. Universal enveloping algebra - Wikipedia

    en.wikipedia.org/wiki/Universal_enveloping_algebra

    In mathematics, the universal enveloping algebra of a Lie algebra is the unital associative algebra whose representations correspond precisely to the representations of that Lie algebra. Universal enveloping algebras are used in the representation theory of Lie groups and Lie algebras.

  9. Two envelopes problem - Wikipedia

    en.wikipedia.org/wiki/Two_envelopes_problem

    The problem concerns two envelopes, each containing an unknown amount of money. The two envelopes problem, also known as the exchange paradox, is a paradox in probability theory. It is of special interest in decision theory and for the Bayesian interpretation of probability theory. It is a variant of an older problem known as the necktie paradox.