3,087 research outputs found
Noncommmutative theorems: Gelfand Duality, Spectral, Invariant Subspace, and Pontryagin Duality
We extend the Gelfand-Naimark duality of commutative C*-algebras, "A
COMMUTATIVE C*-ALGEBRA -- A LOCALLY COMPACT HAUSDORFF SPACE" to "A
C*-ALGEBRA--A QUOTIENT OF A LOCALLY COMPACT HAUSDORFF SPACE". Thus, a
C*-algebra is isomorphic to the convolution algebra of continuous regular Borel
measures on the topological equivalence relation given by the above mentioned
quotient. In commutative case this reduces to Gelfand-Naimark theorem.
Applications: 1) A simultaneous extension, to arbitrary Hilbert space
operators, of Jordan Canonical Form and Spectral Theorem of normal operators 2)
A functional calculus for arbitrary operators. 3) Affirmative solution of
Invariant Subspace Problem. 4) Extension of Pontryagin duality to nonabelian
groups, and inevitably to groups whose underlying topological space is
noncommutative.Comment: 10 page
Electrically controlled Bragg resonances of an ambichiral electro-optic structure: oblique incidence
The Pockels effect can increase the effective birefringence of ambichiral,
electro--optic rejection filters made of materials with a point
group symmetry, when a dc electric field is applied parallel to the axis of
nonhomogeneity. The reflectances and the transmittances of such an ambichiral
structure for obliquely incident plane waves is solvable through a
boundary-value problem that is formulated using the frequency-domain Maxwell
equations, the constitutive equations that contain the Pockels effect, and
standard algebraic techniques for handling 4x4 matrix ordinary differential
equations. The Bragg resonance peaks, for different
circular-polarized-incidence conditions, blueshift as the angle of incidence
increases. These blueshifts are unaffected by the sign of the dc electric
field.Comment: 11 page
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