Search results for "46"
showing 10 items of 1176 documents
Non linear pseudo-bosons versus hidden Hermiticity
2011
The increasingly popular concept of a hidden Hermiticity of operators (i.e., of their Hermiticity with respect to an {\it ad hoc} inner product in Hilbert space) is compared with the recently introduced notion of {\em non-linear pseudo-bosons}. The formal equivalence between these two notions is deduced under very general assumptions. Examples of their applicability in quantum mechanics are discussed.
Generalized Riesz systems and orthonormal sequences in Krein spaces
2018
We analyze special classes of bi-orthogonal sets of vectors in Hilbert and in Krein spaces, and their relations with generalized Riesz systems. In this way, the notion of the first/second type sequences is introduced and studied. We also discuss their relevance in some concrete quantum mechanical system driven by manifestly non self-adjoint Hamiltonians.
Implementability of Liouville Evolution, Koopman and Banach-Lamperti Theorems in Classical and Quantum Dynamics
2002
We extend the concept of implementability of semigroups of evolution operators associated with dynamical systems to quantum case. We show that such an extension can be properly formulated in terms of Jordan morphisms and isometries on non-commutative Lp spaces. We focus our attention on a non-commutative analog of the Banach-Lamperti theorem.
On decoupling in Banach spaces
2021
AbstractWe consider decoupling inequalities for random variables taking values in a Banach space X. We restrict the class of distributions that appear as conditional distributions while decoupling and show that each adapted process can be approximated by a Haar-type expansion in which only the pre-specified conditional distributions appear. Moreover, we show that in our framework a progressive enlargement of the underlying filtration does not affect the decoupling properties (in particular, it does not affect the constants involved). As a special case, we deal with one-sided moment inequalities for decoupled dyadic (i.e., Paley–Walsh) martingales and show that Burkholder–Davis–Gundy-type in…
Activation of the Cyano Group at Imidazole via Copper Stimulated Alcoholysis
2019
Reactions of 4,5-dicyano-1-methylimidazole with CuX2 (X = Cl, Br) in alcohol solvents (ethanol and methanol) resulted in the formation of Cu(II) carboximidate complexes [CuCl2(5- cyano-4-C(OEt)N-1-methylimidazole)(EtOH)] (1), [Cu2(µ
Sterile neutrino portal to Dark Matter II: exact dark symmetry
2017
We analyze a simple extension of the Standard Model (SM) with a dark sector composed of a scalar and a fermion, both singlets under the SM gauge group but charged under a dark sector symmetry group. Sterile neutrinos, which are singlets under both groups, mediate the interactions between the dark sector and the SM particles, and generate masses for the active neutrinos via the seesaw mechanism. We explore the parameter space region where the observed Dark Matter relic abundance is determined by the annihilation into sterile neutrinos, both for fermion and scalar Dark Matter particles. The scalar Dark Matter case provides an interesting alternative to the usual Higgs portal scenario. We also…
"Table 3" of "The e+ e- ---> pi+ pi- pi+ pi-, K+ K- pi+ pi-, and K+ K- K+ K- cross sections at center-of-mass energies 0.5-GeV to 4.5-GeV measured…
2006
Measured K+ K- K+ K- cross sections. The errors are statistical only.
Cognitive Deficits in Chronic Stroke Patients: Neuropsychological Assessment, Depression, and Self-Reports
2017
<b><i>Background:</i></b> Following stroke, clinicians are challenged to detect and untangle symptoms of cognitive dysfunction and mood disorders. Additionally, they need to evaluate the informative value of self-reports to identify patients in need of further attendance. <b><i>Aims:</i></b> To examine the association between neuropsychological measures, symptoms of depression, and self-reported cognitive function. <b><i>Methods:</i></b> One-hundred and five chronic stroke patients underwent assessment covering 6 cognitive domains and answered the Hospital Anxiety and Depression Scale and the Memory and Thinking Scale f…
Quasiadditivity of Variational Capacity
2013
We study the quasiadditivity property (a version of superadditivity with a multiplicative constant) of variational capacity in metric spaces with respect to Whitney type covers. We characterize this property in terms of a Mazya type capacity condition, and also explore the close relation between quasiadditivity and Hardy's inequality.
New insights into the surface functionalities and adsorption evolution of water molecules on silica gel surface: A study by second derivative near in…
2010
Accepted version of an article in the journal: Vibrational Spectroscopy. Published version available on Science Direct: http://dx.doi.org/10.1016/j.vibspec.2010.06.003 Surface functionalities and adsorption evolution of water molecules on silica gel samples were studied by second derivative near infrared spectroscopy. Four different silica gel samples with varying surface area were used in this experiment. Each of the dry samples was allowed to equilibrate with surrounding air and the near infrared spectra were accumulated at different time intervals using reflectance technique. The evolved spectra were analysed using second derivative technique to study the adsorption evolution of water mo…