When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Perturbation theory (quantum mechanics) - Wikipedia

    en.wikipedia.org/wiki/Perturbation_theory...

    6.1 Example of first-order perturbation theory ... The first-order change in the n-th energy eigenket has a contribution from each of the energy eigenstates k ≠ n.

  3. Phase transition - Wikipedia

    en.wikipedia.org/wiki/Phase_transition

    First-order phase transitions exhibit a discontinuity in the first derivative of the free energy with respect to some thermodynamic variable. [6] The various solid/liquid/gas transitions are classified as first-order transitions because they involve a discontinuous change in density, which is the (inverse of the) first derivative of the free ...

  4. Situation calculus - Wikipedia

    en.wikipedia.org/wiki/Situation_calculus

    The situation calculus represents changing scenarios as a set of first-order logic formulae. The basic elements of the calculus are: The actions that can be performed in the world; The fluents that describe the state of the world; The situations; A domain is formalized by a number of formulae, namely:

  5. Euler method - Wikipedia

    en.wikipedia.org/wiki/Euler_method

    For this reason, the Euler method is said to be a first-order method, while the midpoint method is second order. We can extrapolate from the above table that the step size needed to get an answer that is correct to three decimal places is approximately 0.00001, meaning that we need 400,000 steps.

  6. List of first-order theories - Wikipedia

    en.wikipedia.org/wiki/List_of_first-order_theories

    Use ordinary first-order logic, but add a new unary predicate "Set", where "Set(t)" means informally "t is a set". Use ordinary first-order logic, and instead of adding a new predicate to the language, treat "Set(t)" as an abbreviation for "∃y t∈y" Some first-order set theories include: Weak theories lacking powersets:

  7. First-order - Wikipedia

    en.wikipedia.org/wiki/First-order

    First-order logic, a formal logical system used in mathematics, philosophy, linguistics, and computer science; First-order predicate, a predicate that takes only individual(s) constants or variables as argument(s) First-order predicate calculus; First-order theorem provers; First-order theory; Monadic first-order logic

  8. First-order logic - Wikipedia

    en.wikipedia.org/wiki/First-order_logic

    First-order logic also satisfies several metalogical theorems that make it amenable to analysis in proof theory, such as the Löwenheim–Skolem theorem and the compactness theorem. First-order logic is the standard for the formalization of mathematics into axioms, and is studied in the foundations of mathematics.

  9. Time constant - Wikipedia

    en.wikipedia.org/wiki/Time_constant

    First order LTI systems are characterized by the differential equation + = where τ represents the exponential decay constant and V is a function of time t = (). The right-hand side is the forcing function f(t) describing an external driving function of time, which can be regarded as the system input, to which V(t) is the response, or system output.