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Laplace expansion (potential)

In physics, the Laplace expansion of potentials that are directly proportional to the inverse of the distance ( 1 / r ), such as Newton's gravitational potential or Coulomb's electrostatic potential, expresses them in terms of the spherical Legendre polynomials.

Version
v1 · 2026-09-28 · History
Domain-specific #
10315
Domain group
Natural Sciences
Origin domain
Physics
Subdomains
Potential Theory, Multipole Expansion → Physics

Core Idea

Laplace expansion (potential) is treated here as the recurring crossdomainmodelsstructuresrepresentations identity summarized by this source-grounded definition: In physics, the Laplace expansion of potentials that are directly proportional to the inverse of the distance ( 1 / r ), such as Newton's gravitational potential or Coulomb's electrostatic potential, expresses them in terms of the spherical Legendre polynomials. In physics, the Laplace expansion of potentials that are directly proportional to the inverse of the distance ( 1 / r ), such as Newton's gravitational potential or Coulomb's electrostatic potential, expresses them in terms of the spherical Legendre polynomials.

Scope of Application

  • By the law of cosines,. We find here the generating function of the Legendre polynomials P\ell(\cos\gamma).

  • Neumann expansion. A similar equation has been derived by Carl Gottfried Neumann that allows expression of 1/r in prolate spheroidal coordinates as a series.

  • Neumann expansion. where \mathcal{P}\ell^{m}(z) and \mathcal{Q}\ell^{m}(z) are associated Legendre functions of the first and second kind, respectively, defined such that they are real for.

  • Formulation. The function Y^m\ell is a normalized spherical harmonic function.

  • Documented setting. In quantum mechanical calculations on atoms the expansion is used in the evaluation of integrals of the inter-electronic repulsion.

Clarity

A clear use of Laplace expansion (potential) names the carrier, the operative relation, and the conditions under which the source treats the identity as present. The minimal definition is In physics, the Laplace expansion of potentials that are directly proportional to the inverse of the distance ( 1 / r ), such as Newton's gravitational potential or Coulomb's electrostatic potential, expresses them in terms of the spherical Legendre polynomials.

Manages Complexity

Laplace expansion (potential) compresses multiple crossdomainmodelsstructuresrepresentations details into a stable diagnostic relation. The source shows both the central mechanism—the Laplace expansion is in fact the expansion of the inverse distance between two points.—and the practical consequence—further r < is min(r, r′) and r > is max(r, r′). This compression makes cases comparable while leaving parameters, conventions, exceptions, and evidential quality explicit.

Abstract Reasoning

  1. Type the carrier. Identify the crossdomainmodelsstructuresrepresentations entities to which the claim applies.
  2. State the relation. Use the source-grounded identity: In physics, the Laplace expansion of potentials that are directly proportional to the inverse of the distance ( 1 / r ), such as Newton's gravitational potential or Coulomb's electrostatic potential, expresses them in terms of the spherical Legendre polynomials.
  3. Check operation and conditions. Let the points have position vectors \textbf{r} and \textbf{r}' , then the Laplace expansion is. 4.

Knowledge Transfer

Within the home domain. Knowledge about Laplace expansion (potential) transfers literally when a new case preserves the same carrier type, relation, and recognition test. We find here the generating function of the Legendre polynomials P\ell(\cos\gamma). A similar equation has been derived by Carl Gottfried Neumann that allows expression of 1/r in prolate spheroidal coordinates as a series. Beyond the home domain. No canonical parent is asserted for Laplace expansion (potential).

Neighborhood in Abstraction Space

Laplace expansion (potential) sits in a moderately populated region (46th percentile for distinctiveness): it has near-neighbors but no dense thicket of look-alikes.

Family — Continuum Mechanics & Field Models (42 abstractions)

Nearest neighbors

Computed from structural-signature embeddings · 2026-10-08