1.

Record Nr.

UNINA9910257409303321

Titolo

Applications of Self-Adjoint Extensions in Quantum Physics [[electronic resource] ] : Proceedings of a Conference Held at the Laboratory of Theoretical Physics, JINR, Dubna, USSR, September 29–October 1, 1987 / / edited by Pavel Exner, Petr Seba

Pubbl/distr/stampa

Berlin, Heidelberg : , : Springer Berlin Heidelberg : , : Imprint : Springer, , 1989

ISBN

3-540-46104-3

Edizione

[1st ed. 1989.]

Descrizione fisica

1 online resource (X, 275 p. 3 illus.)

Collana

Lecture Notes in Physics, , 0075-8450 ; ; 324

Disciplina

530.12

Soggetti

Quantum physics

Quantum computers

Spintronics

Mathematical analysis

Analysis (Mathematics)

Quantum Physics

Quantum Information Technology, Spintronics

Analysis

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Note generali

Bibliographic Level Mode of Issuance: Monograph

Nota di contenuto

Zero-range interactions with an internal structure -- Evolution equations and selfadjoint extensions -- Energy-dependent interactions and the extension theory -- On perturbations for self-adjoint generators of feller processes -- Singular perturbations defined by forms -- Covariant markovian random fields in four space-time dimensions with nonlinear electromagnetic interaction -- Point interaction Hamiltonians for crystals with random defects -- Scattering on a random point potential -- Faddeev equations for three composite particles -- On the point interaction of three particles -- A resonating- group model with extended channel spaces -- The problem of a few quasi-particles in solid-state physics -- Surfaces with an internal structure -- Spectral properties of the laplacian with attractive boundary conditions -- Quantum junctions and the self-adjoint



extensions theory -- The extension theory and diffraction problems -- Hamiltonians with additional kinetic energy terms on hypersurfaces -- Thin lattices as waveguides -- Quantum waveguides -- An exactly solvable model of a crystal with non-point atoms.

Sommario/riassunto

The shared purpose in this collection of papers is to apply the theory of self-adjoint extensions of symmetry operators in various areas of physics. This allows the construction of exactly solvable models in quantum mechanics, quantum field theory, high energy physics, solid-state physics, microelectronics and other fields. The 20 papers selected for these proceedings give an overview of this field of research unparallelled in the published literature; in particular the views of the leading schools are clearly presented. The book will be an important source for researchers and graduate students in mathematical physics for many years to come. In these proceedings, researchers and graduate students in mathematical physics will find ways to construct exactly solvable models in quantum mechanics, quantum field theory, high energy physics, solid-state physics, microelectronics and other fields.

2.

Record Nr.

UNINA9910821645703321

Titolo

Living with xenophobia : Zimbabwean informal enterprise in South Africa / / Jonathan Crush [and three others]

Pubbl/distr/stampa

Waterloo, Ontario : , : Southern African Migration Programme, , 2017

©2017

ISBN

1-920596-39-9

Descrizione fisica

1 online resource (1 PDF (33 pages) :) : illustrations

Collana

SAMP Migration Policy Series ; ; Number 77

Disciplina

305.80096

Soggetti

Xenophobia - Africa

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Note generali

Issued as part of book collections on Project MUSE.

Nota di bibliografia

Includes bibliographical references.

Nota di contenuto

Introduction -- Migration for survival -- Experiencing xenophobia -- Responses to xenophobic violence -- Perceptions of government inaction -- Conclusion.



Sommario/riassunto

This report examines the impact of xenophobic violence on Zimbabweans who are trying to make a living in the South African informal sector and finds that xenophobic violence has several key characteristics that put them at constant risk of losing their livelihoods and their lives. The businesses run by migrants and refugees in the informal sector are a major target of South Africa's extreme xenophobia. Attitudinal surveys clearly show that South Africans differentiate migrants by national origin and that Zimbabweans are amongst the most disliked. This report is based on a survey of informal sector enterprises in Cape Town and Johannesburg; and 50 in-depth interviews with Zimbabwean informal business owners in Cape Town, Johannesburg and Polokwane who had been affected by xenophobic violence. In many areas, community leaders are ineffective in dealing with the violence and, in some cases, they actively foment hostility and instigate attacks. The fact that migrant entrepreneurs provide goods, including food, at competitive prices and offer credit to consumers is clearly insufficient to protect them when violence erupts. However, the deep-rooted crisis in Zimbabwe makes return home a non-viable option and Zimbabweans instead adopt several self-protection strategies, none of which is ultimately an insurance against xenophobic attack. The findings in this report demonstrate that xenophobic violence fails in its two main aims: to drive migrant entrepreneurs out of business and to drive them out of the country.