3,741 research outputs found
Phonon Squeezing in a Superconducting Molecular Transistor
Josephson transport through a single molecule or carbon nanotube is
considered in the presence of a local vibrational mode coupled to the
electronic charge. The ground-state solution is obtained exactly in the limit
of a large superconducting gap, and is extended to the general case by
variational analysis. Coherent charge fluctuations are entangled with
non-classical phonon states. The Josephson current induces squeezing of the
phonon mode, which is controlled by the superconducting phase difference and by
the junction asymmetry. Optical probes of non-classical phonon states are
briefly discussed
Theoretical Validity and Empirical Utility of a Constructionist Analytics
Wing-Chung Ho offers an extensive critique of what he calls our âradical constructionist approach to family experience,â questioning the theoretical validity and empirical utility of the research program. This article responds to the charges in the broader context of the program\u27s constructionist analytics, discussing family\u27s experiential location, organizational embeddedness, and the importance of ethnographic sensibility. A brief extract of situated talk and interaction is presented to illustrate the discursive complexity and institutional bearings of family as a category of experience. The conclusion takes up the issue of whether the program is radical in conceptualization and empirical realization
Animating Interview Narratives
This chapter discusses the implications of viewing the interview as an actively constructed conversation through which narrative data are produced. It explores the ramifications of framing the interview and resulting data as by-products of interpretive practice - the whats and hows of an animated process involving active subjects behind interview participants. Matters of reliability, validity, bias, and rigor are considered
Don\u27t Argue with the Members
Mel Pollner regularly cautioned researchers not to argue with the members of settings under consideration. He warned against substituting the researcherâs meaning for the meanings of those being studied. This article discusses facets of the caution as they relate to the research process. Seemingly simple, the tenet is nuanced in application. The article adds to the nuance by distinguishing what is called the âreplacementâ of meaning with the âdisplacementâ of meaning, providing a way of understanding what members could mean if the contexts and settings of their accounts were taken into consideration
Lowest Order Effective Field Theory for the weak interaction
The interaction, responsible for the decay of
hypernuclei, is studied by means of an Effective Field Theory where the long
range physics is described by pion and kaon exchange mechanisms, and its short
range counterpart is obtained from the most general non-derivative local
four-fermion interaction. We show that, including the Lowest Order Parity
Conserving contact terms, allows us to reproduce the total decay rates for
, and with
a reasonable value of , while in order to get a prediction for
the Parity Violating (PV) asymmetry compatible with experiments, we have to
include the Lowest Order PV contact pieces.Comment: 3 pages, no figures. Contribution to the 17th International IUPAP
Conference on Few-body Problems in Physics, June 5-10, 2003 Durham, North
Carolina, USA. Uses espcrc1.st
Anomalies in Quantum Mechanics: the 1/r^2 Potential
An anomaly is said to occur when a symmetry that is valid classically becomes
broken as a result of quantization. Although most manifestations of this
phenomenon are in the context of quantum field theory, there are at least two
cases in quantum mechanics--the two dimensional delta function interaction and
the 1/r^2 potential. The former has been treated in this journal; in this
article we discuss the physics of the latter together with experimental
consequences.Comment: 16 page latex file; to be published in Am. J. Phy
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