Symplectic representation

Symplectic representation

In mathematical field of representation theory, a symplectic representation is a representation of a group or a Lie algebra on a symplectic vector space ("V", "ω") which preserves the symplectic form "ω". Here "ω" is a nondegenerate skew symmetric bilinear form:omegacolon V imes V o mathbb Fwhere F is the field of scalars. A representation of a group "G" preserves "ω" if:omega(gcdot v,gcdot w)= omega(v,w)for all "g" in "G" and "v", "w" in "V", whereas a representation of a Lie algebra g preserves "ω" if:omega(xicdot v,w)+omega(v,xicdot w)=0for all "ξ" in g and "v", "w" in "V". Thus a representation of "G" or g is equivalently a group or Lie algebra homomorphism from "G" or g to the symplectic group Sp("V","ω") or its Lie algebra sp("V","ω")

If G is a compact group (for example, a finite group), and F is the field of complex numbers, then by introducing a compatible unitary structure (which exists by an averaging argument), one can show that any complex symplectic representation is a quaternionic representation. Quaternionic representations of finite or compact groups are often called symplectic representations, and may be identified using the Frobenius-Schur indicator.

References

*Fulton-Harris.


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Symplectic group — For finite groups with all characteristc abelian subgroups cyclic, see group of symplectic type. Group theory …   Wikipedia

  • Symplectic matrix — In mathematics, a symplectic matrix is a 2n times; 2n matrix M (whose entries are typically either real or complex) satisfying the condition:M^T Omega M = Omega,.where MT denotes the transpose of M and Omega; is a fixed nonsingular, skew… …   Wikipedia

  • Symplectic vector space — In mathematics, a symplectic vector space is a vector space V equipped with a nondegenerate, skew symmetric, bilinear form omega; called the symplectic form. Explicitly, a symplectic form is a bilinear form omega; : V times; V rarr; R which is *… …   Wikipedia

  • Symplectic cut — In mathematics, specifically in symplectic geometry, the symplectic cut is a geometric modification on symplectic manifolds. Its effect is to decompose a given manifold into two pieces. There is an inverse operation, the symplectic sum, that… …   Wikipedia

  • Representation of a Lie group — In mathematics and theoretical physics, the idea of a representation of a Lie group plays an important role in the study of continuous symmetry. A great deal is known about such representations, a basic tool in their study being the use of the… …   Wikipedia

  • Quaternionic representation — In mathematical field of representation theory, a quaternionic representation is a representation on a complex vector space V with an invariant quaternionic structure, i.e., an antilinear equivariant map:jcolon V o V, which satisfies:j^2=… …   Wikipedia

  • List of representation theory topics — This is a list of representation theory topics, by Wikipedia page. See also list of harmonic analysis topics, which is more directed towards the mathematical analysis aspects of representation theory. Contents 1 General representation theory 2… …   Wikipedia

  • Restricted representation — In mathematics, restriction is a fundamental construction in representation theory of groups. Restriction forms a representation of a subgroup from a representation of the whole group. Often the restricted representation is simpler to understand …   Wikipedia

  • Coadjoint representation — In mathematics, the coadjoint representation ρ of a Lie group G is the dual of the adjoint representation. Therefore, if g denotes the Lie algebra of G, it is the action of G on the dual space to g. More geometrically, G acts by conjugation on… …   Wikipedia

  • Lie algebra representation — Lie groups …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”