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The price-dividend relationship in inflationary and deflationary regimes
This paper suggests that dividends do not reflect permanent earnings of corporations in periods of high inflation and deflation, and therefore the price-dividend relationship, as predicted by Gordon’s dividend-price model, breaks down. Using data for the US and the UK over the period from 1871 to 2002, nonlinear estimates support the prediction of the model
Hot-wire and hot-film anemometry
The circuit techniques, electronics, dynamic properties, and the applications of the anemometers are given
High-harmonic generation from arbitrarily oriented diatomic molecules including nuclear motion and field-free alignment
We present a theoretical model of high-harmonic generation from diatomic
molecules. The theory includes effects of alignment as well as nuclear motion
and is used to predict results for N, O, H and D. The results
show that the alignment dependence of high-harmonics is governed by the
symmetry of the highest occupied molecular orbital and that the inclusion of
the nuclear motion in the theoretical description generally reduces the
intensity of the harmonic radiation. We compare our model with experimental
results on N and O, and obtain very good agreement.Comment: 12 pages, 8 figures, 2 tables; legends revised on Figs. 1,3,4,6 and
How physics instruction impacts students' beliefs about learning physics: A meta-analysis of 24 studies
In this meta-analysis, we synthesize the results of 24 studies using the
Colorado Learning Attitudes about Science Survey (CLASS) and the Maryland
Physics Expectations Survey (MPEX) to answer several questions: (1) How does
physics instruction impact students' beliefs? (2) When do physics majors
develop expert-like beliefs? and (3) How do students' beliefs impact their
learning of physics? We report that in typical physics classes, students'
beliefs deteriorate or at best stay the same. There are a few types of
interventions, including an explicit focus on model-building and/or developing
expert- like beliefs that lead to significant improvements in beliefs. Further,
small courses and those for elementary education and non-science majors also
result in improved beliefs. However, because the available data oversamples
certain types of classes, it is unclear whether these improvements are actually
due to the interventions, or due to the small class size, or student population
typical of the kinds of classes in which these interventions are most often
used. Physics majors tend to enter their undergraduate education with more
expert-like beliefs than non-majors and these beliefs remain relatively stable
throughout their undergraduate careers. Thus, typical physics courses appear to
be selecting students who already have strong beliefs, rather than supporting
students in developing strong beliefs. There is a small correlation between
students' incoming beliefs about physics and their gains on conceptual
mechanics surveys. This suggests that students with more expert-like incoming
beliefs may learn more in their physics courses, but this finding should be
further explored and replicated. Some unanswered questions remain. To answer
these questions, we advocate several specific types of future studies.Comment: 30 pages. Accepted to Phys Rev ST-PE
Experimental Bell Inequality Violation with an Atom and a Photon
We report the measurement of a Bell inequality violation with a single atom
and a single photon prepared in a probabilistic entangled state. This is the
first demonstration of such a violation with particles of different species.
The entanglement characterization of this hybrid system may also be useful in
quantum information applications.Comment: 4 pages, 2 figure
High-order harmonic generation from polyatomic molecules including nuclear motion and a nuclear modes analysis
We present a generic approach for treating the effect of nuclear motion in
the high-order harmonic generation from polyatomic molecules. Our procedure
relies on a separation of nuclear and electron dynamics where we account for
the electronic part using the Lewenstein model and nuclear motion enters as a
nuclear correlation function. We express the nuclear correlation function in
terms of Franck-Condon factors which allows us to decompose nuclear motion into
modes and identify the modes that are dominant in the high-order harmonic
generation process. We show results for the isotopes CH and CD and
thereby provide direct theoretical support for a recent experiment [Baker {\it
et al.}, Science {\bf 312}, 424 (2006)] that uses high-order harmonic
generation to probe the ultra-fast structural nuclear rearrangement of ionized
methane.Comment: 6 pages, 6 figure
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