190,263 research outputs found
Reply to ``Comment on `On the inconsistency of the Bohm-Gadella theory with quantum mechanics'''
In this reply, we show that when we apply standard distribution theory to the
Lippmann-Schwinger equation, the resulting spaces of test functions would
comply with the Hardy axiom only if classic results of Paley and Wiener, of
Gelfand and Shilov, and of the theory of ultradistributions were wrong. As
well, we point out several differences between the ``standard method'' of
constructing rigged Hilbert spaces in quantum mechanics and the method used in
Time Asymmetric Quantum Theory.Comment: 13 page
Work-Related Musculoskeletal Disorders Among Dentists and Orthodontists
WORK-RELATED MUSCULOSKELETAL DISORDERS AMONG DENTISTS AND ORTHODONTISTS
A thesis submitted in partial fulfillment of the requirements for the degree of
Master of Science in Dentistry at Virginia Commonwealth University.
by
Natalie R. La Rochelle
Thesis Director: Dr. Eser Tüfekçi, D.D.S., M.S., Ph.D., M.S.H.A.
Professor, Department of Orthodontics
Virginia Commonwealth University
Richmond, Virginia
May 2017
The practice of dentistry is physically demanding due to static and dynamic postures sustained daily throughout careers. Previous literature suggests that work-related musculoskeletal disorders (WMSD) are not solely the result of work habits, but also due to the individual, his or her physical makeup, genetics, and personal lifestyle. A 33-question survey was distributed to 1000 general dentists and 2300 orthodontists. The overall prevalence of work-related musculoskeletal disorders was greater among dentists and most often reported as self-limiting. Dentists were three times more likely than orthodontists to report WMSD; females were twice as likely to report WMSD than males; those who sought alternative medical remedies were two times more likely to have WMSD; and practitioners 6-10 years in practice were least likely to report WMSD. Dentists reported sitting in static positions longer than orthodontists; and those with WMSD indicated exercising, stretching, and seeking alternative health remedies more than dentists without WMSD
Description of resonances within the rigged Hilbert space
The spectrum of a quantum system has in general bound, scattering and
resonant parts. The Hilbert space includes only the bound and scattering
spectra, and discards the resonances. One must therefore enlarge the Hilbert
space to a rigged Hilbert space, within which the physical bound, scattering
and resonance spectra are included on the same footing. In these lectures, I
will explain how this is done.Comment: 23 pages; written version of the five-lecture course delivered at the
2006 Summer School of CINVESTAV, Mexico City, July 200
Replacing the Breit-Wigner amplitude by the complex delta function to describe resonances
Whenever the Breit-Wigner amplitude appears in a calculation,there are many
instances (e.g., Fermi's two-level system and the Weisskopf-Wigner
approximation) where energy integrations are extended from the scattering
spectrum of the Hamiltonian to the whole real line. Such extensions are
performed in order to obtain a desirable, causal result. In this paper, we
recall several of those instances and show that substituting the Breit-Wigner
amplitude by the complex delta function allows us to recover such desirable
results without having to extend energy integrations outside of the scattering
spectrum.Comment: Invited, refereed contribution to the proceedings of the YKIS2009
workshop, Kyoto, Japan
The Rigged Hilbert Space of the Free Hamiltonian
We explicitly construct the Rigged Hilbert Space (RHS) of the free
Hamiltonian . The construction of the RHS of provides yet another
opportunity to see that when continuous spectrum is present, the solutions of
the Schrodinger equation lie in a RHS rather than just in a Hilbert space.Comment: 18 pages. Invited, refereed contribution to the Jaca proceedings; v2:
minor, cosmetic change
The rigged Hilbert space approach to the Lippmann-Schwinger equation. Part I
We exemplify the way the rigged Hilbert space deals with the
Lippmann-Schwinger equation by way of the spherical shell potential. We
explicitly construct the Lippmann-Schwinger bras and kets along with their
energy representation, their time evolution and the rigged Hilbert spaces to
which they belong. It will be concluded that the natural setting for the
solutions of the Lippmann-Schwinger equation--and therefore for scattering
theory--is the rigged Hilbert space rather than just the Hilbert space.Comment: 34 pages, 1 figur
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