Maupertuis' Principle - Mathematical Formulation

Mathematical Formulation

Maupertuis' principle states that the true path of a system described by generalized coordinates between two specified states and is an extremum (i.e., a stationary point, a minimum, maximum or saddle point) of the abbreviated action functional


\mathcal{S}_{0} \ \stackrel{\mathrm{def}}{=}\
\int \mathbf{p} \cdot d\mathbf{q}

where are the conjugate momenta of the generalized coordinates, defined by the equation


p_{k} \ \stackrel{\mathrm{def}}{=}\ \frac{\partial L}{\partial\dot{q}_{k}}

where is the Lagrangian function for the system. In other words, any first-order perturbation of the path results in (at most) second-order changes in . Note that the abbreviated action is not a function, but a functional, i.e., something that takes as its input a function (in this case, the path between the two specified states) and returns a single number, a scalar.

Read more about this topic:  Maupertuis' Principle

Famous quotes containing the words mathematical and/or formulation:

    As we speak of poetical beauty, so ought we to speak of mathematical beauty and medical beauty. But we do not do so; and that reason is that we know well what is the object of mathematics, and that it consists in proofs, and what is the object of medicine, and that it consists in healing. But we do not know in what grace consists, which is the object of poetry.
    Blaise Pascal (1623–1662)

    In necessary things, unity; in disputed things, liberty; in all things, charity.
    —Variously Ascribed.

    The formulation was used as a motto by the English Nonconformist clergyman Richard Baxter (1615-1691)