Results 11 to 20 of about 213 (150)
Non-commutative functional calculus: Unbounded operators [PDF]
Journal of Geometry and Physics, 2009 In a recent work, \cite{cgss}, we developed a functional calculus for bounded operators defined on quaternionic Banach spaces. In this paper we show how the results from \cite{cgss} can be extended to the unbounded case, and we highlight the crucial differences between the two cases.
Sabadini, Irene +11 more
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Quasi-shuffle Algebras in Non-commutative Stochastic Calculus [PDF]
, 2021 This chapter is divided into two parts. The first is largely expository and builds on Karandikar's axiomatisation of It{\^o} calculus for matrix-valued semimartin-gales. Its aim is to unfold in detail the algebraic structures implied for iterated It{\^o} and Stratonovich integrals. These constructions generalise the classical rules of Chen calculus for
Ebrahimi-Fard, Kurusch +1 more
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Relative unitary commutator calculus, and applications
Journal of Algebra, 2011 This note revisits localisation and patching method in the setting of generalised unitary groups. Introducing certain subgroups of relative elementary unitary groups, we develop relative versions of the conjugation calculus and the commutator calculus in unitary groups, which are both more general, and substantially easier than the ones available in ...
Hazrat, Roozbeh (R16959) +2 more
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Noncommutative integration calculus [PDF]
Journal of Mathematical Physics, 1995 A noncommutative integration calculus arising in the mathematical description of Schwinger terms of fermion–Yang–Mills systems is discussed. The differential complexes of forms u0[ε,u1]...[ε,un] with ε a grading operator on a Hilbert space ℋ and ui bounded operators on ℋ which naturally contains the compactly supported de Rham forms on Rd (i.e., ε is ...
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Relative commutator calculus in Chevalley groups
Journal of Algebra, 2013 We revisit localisation and patching method in the setting of Chevalley groups. Introducing certain subgroups of relative elementary Chevalley groups, we develop relative versions of the conjugation calculus and the commutator calculus in Chevalley groups $G( ,R)$, $\rk( )\geq 2$, which are both more general, and substantially easier than the ones ...
Hazrat, Roozbeh (R16959) +2 more
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Two theorems in the commutator calculus [PDF]
Transactions of the American Mathematical Society, 1972 Let F = ⟨ a , b ⟩ F = \langle a,b\rangle . Let F n {F_n} be the nth subgroup of the lower central series. Let p be a prime. Let c 3 > c
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!COMMUTANT LIFTING, TENSOR ALGEBRAS, AND FUNCTIONAL CALCULUS [PDF]
Proceedings of the Edinburgh Mathematical Society, 2001 AbstractA non-commutative multivariable analogue of Parrott’s generalization of the Sz.-Nagy–Foia\c{s} commutant lifting theorem is obtained. This yields Tomita-type commutant results and interpolation theorems (e.g. Sarason, Nevanlinna–Pick, Carathéodory) for $F_n^\infty\,\bar{\otimes}\,\M$, the weakly-closed algebra generated by the spatial tensor ...
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The Huang–Yang Formula for the Low‐Density Fermi Gas: Upper Bound
Communications on Pure and Applied Mathematics, EarlyView.ABSTRACT We study the ground state energy of a gas of spin 1/2$1/2$ fermions with repulsive short‐range interactions. We derive an upper bound that agrees, at low density ϱ$\varrho$, with the Huang–Yang conjecture. The latter captures the first three terms in an asymptotic low‐density expansion, and in particular the Huang–Yang correction term of order
Emanuela L. Giacomelli +3 more
wiley +1 more source
Quenching the Hubbard Model: Comparison of Nonequilibrium Green's Function Methods
Contributions to Plasma Physics, EarlyView.ABSTRACT We benchmark nonequilibrium Green's function (NEGF) approaches for interaction quenches in the half‐filled Fermi–Hubbard model in one and two dimensions. We compare fully self‐consistent two‐time Kadanoff–Baym equations (KBE), the generalized Kadanoff–Baym ansatz (GKBA), and the recently developed NEGF‐based quantum fluctuations approach (NEGF‐
Jan‐Philip Joost +3 more
wiley +1 more source
Kinetic Contribution to the Arbitrary Order Odd Frequency Moments of the Dynamic Structure Factor
Contributions to Plasma Physics, EarlyView.ABSTRACT An exact expression is derived for the kinetic contribution to the odd (arbitrary order) frequency moments of the dynamic structure factor via a finite summation that features averages of even (all lower orders) powers of the momentum over the exact momentum distribution.
Panagiotis Tolias +2 more
wiley +1 more source