Search results for "intertwining"
showing 10 items of 10 documents
Intertwining operators between different Hilbert spaces: connection with frames
2009
In this paper we generalize a strategy recently proposed by the author concerning intertwining operators. In particular we discuss the possibility of extending our previous results in such a way to construct (almost) isospectral self-adjoint operators living in different Hilbert spaces. Many examples are discussed in details. Many of them arise from the theory of frames in Hilbert spaces, others from the so-called g-frames.
Quons, coherent states and intertwining operators
2009
We propose a differential representation for the operators satisfying the q-mutation relation $BB^\dagger-q B^\dagger B=\1$ which generalizes a recent result by Eremin and Meldianov, and we discuss in detail this choice in the limit $q\to1$. Further, we build up non-linear and Gazeau-Klauder coherent states associated to the free quonic hamiltonian $h_1=B^\dagger B$. Finally we construct almost isospectrals quonic hamiltonians adopting the results on intertwining operators recently proposed by the author.
Non-isospectral Hamiltonians, intertwining operators and hidden hermiticity
2011
We have recently proposed a strategy to produce, starting from a given hamiltonian $h_1$ and a certain operator $x$ for which $[h_1,xx^\dagger]=0$ and $x^\dagger x$ is invertible, a second hamiltonian $h_2$ with the same eigenvalues as $h_1$ and whose eigenvectors are related to those of $h_1$ by $x^\dagger$. Here we extend this procedure to build up a second hamiltonian, whose eigenvalues are different from those of $h_1$, and whose eigenvectors are still related as before. This new procedure is also extended to crypto-hermitian hamiltonians.
Presentazione
2013
Il testo propone un articolato commento alle posizioni teoriche e alle linee di ricerca progettuale espresse da Michele Argentino, professore ordinario di Design a Palermo circa la necessità di riconquistare il ruolo sociale alla creatività individuale, riprendendosi il desiderio di diventare nuovamente "Homo Faber". Il testo inoltre presenta gli obiettivi della nuova collana scientifica - diretta dall'autrice - dal Titolo " Design e Contesti": intercettare ambiti di ricerca trasversali alle discipline del progetto, favorire gli intrecci tra idee progettuali e percorsi di innovazione socio-culturale, sviluppare nuove strategie produttive compatibili con i diversi aspetti della sostenibilità.
Vector coherent states and intertwining operators
2009
In this paper we discuss a general strategy to construct vector coherent states of the Gazeau-Klauder type and we use them to built up examples of isospectral hamiltonians. For that we use a general strategy recently proposed by the author and which extends well known facts on intertwining operators. We also discuss the possibility of constructing non-isospectral hamiltonians with related eigenstates.
Non-self-adjoint Hamiltonians with complex eigenvalues
2016
Motivated by what one observes dealing with PT-symmetric quantum mechanics, we discuss what happens if a physical system is driven by a diagonalizable Hamiltonian with not all real eigenvalues. In particular, we consider the functional structure related to systems living in finite-dimensional Hilbert spaces, and we show that certain intertwining relations can be deduced also in this case if we introduce suitable antilinear operators. We also analyze a simple model, computing the transition probabilities in the broken and in the unbroken regime.
Mathematical aspects of intertwining operators: the role of Riesz bases
2010
In this paper we continue our analysis of intertwining relations for both self-adjoint and not self-adjoint operators. In particular, in this last situation, we discuss the connection with pseudo-hermitian quantum mechanics and the role of Riesz bases.
Sport and Quality of Life
2022
Negli ultimi trent’anni lo sport ha assunto un significato molto rilevante nella vita delle persone e, seppure con notevoli differenze, sia nei paesi a sviluppo economico avanzato, sia in quelli in via di sviluppo. A livello individuale, esso ha costituito un’area di investimento identitario quando ha assunto la forma di sport spettacolo del quale fruire, alimentando la pratica del tifo e il fandom o costituendo il modello di uno stile di vita vincente; ma anche quando ha assunto la forma di pratica del tempo libero attraverso la quale tenersi in forma, facendo crescere, in questo caso, la diffusione di una cultura della salute e del benessere. Si tratta di due modalità di approcciare al co…
Ekonomiczny nacjonalizm i populizm – przenikające się relacje
2017
The objective of the paper is to analyse two very closely related categories, economic nationalism and economic populism. They intertwine both in the lived politics on the ground and in intellectual debates. Despite a rich interdisciplinary discourse, scholars interested in economic nationalism and economic populism still disagree not only how to explain them, but more fundamentally – about what they are and what their relation is. This paper answers this deficit by addressing the question of the intertwining connections between economic nationalism and populism. In the first instance it reconstructs the basic definitions of economic nationalism – its constitutive elements, its historicity …
Economic Nationalism and Populism – Intertwining Relations
2017
Celem niniejszego artykułu jest zaprezentowanie analizy dwóch, bardzo ściśle powiązanych ze sobą kategorii, nacjonalizmu ekonomicznego oraz ekonomicznego populizmu. Obie kategorie przenikają się zarówno w realnej polityce, jak i w refleksji akademickiej. Mimo bardzo bogatego dyskursu naukowego na temat obydwu, ich badacze cały czas spierają się nie tylko na temat tego jak je wyjaśniać, ale nawet co do ich zasadniczych treści. Zaproponowana analiza stanowi odpowiedź na ten deficyt i próbuje skupić się na związkach ekonomicznego populizmu i nacjonalizmu. W pierwszej kolejności dokonana została rekonstrukcja podstawowych sposobów rozumienia nacjonalizmu ekonomicznego – jego elementów konstytut…