Discrete asymptotic homomorphisms in E-theory and KK-theory

Asymptotic Unitary Equivalence in KK-Theory

A description of the Kasparov group KK(A,B) is given in terms of Cuntz pairs of representations and the notion of proper asymptotic unitary equivalence that we introduce here. The use of the word ‘proper’ reflects the crucial fact that all unitaries implementing the equivalence can be chosen to be compact perturbations of identity. The result has significant applications to the classification t...

Equivariant KK-theory and noncommutative index theory

Asymptotic Spectral Measures: Between Quantum Theory and E-theory

We review the relationship between positive operator-valued measures (POVMs) in quantum measurement theory and asymptotic morphisms in the C∗-algebra E-theory of Connes and Higson. The theory of asymptotic spectral measures, as introduced by Martinez and Trout [1], is integrally related to positive asymptotic morphisms on locally compact spaces via an asymptotic Riesz Representation Theorem. Ex...

Algebraic K-theory of Fredholm Modules and Kk-theory

Kasparov KK-groups KK(A,B) are represented as homotopy groups of the Pedersen-Weibel nonconnective algebraic K-theory spectrum of the additive category of Fredholm (A,B)-bimodules for A and B, respectively, a separable and σ-unital trivially graded real or complex C∗-algebra acted upon by a fixed compact metrizable group.

superstring scatterng from dbranes and wess zumino terms in string theory

دو هدف را برای انجام این پایان نامه دنبال می کنیم . نشان می دهیم که بسط دامنه پراکندگی یک میدان راموند-راموند دو میدان پیمانه ای و یک میدان تاکیونی caat بسط سازگاری است که این نکته بیانگر آنست که بسط تاکیونها که بسط انرژی پایین نیست را یافته ایم و این بسط با بسط aatt,ctta,cta,cttt سازگار است با مقایسه با دامنه پراکندگی تعدادی از تصحیحات کنشهای tachyonic dbi, wess-zumino را می یابیم .