47,527 research outputs found
On Higher Order Gravities, Their Analogy to GR, and Dimensional Dependent Version of Duff's Trace Anomaly Relation
An almost brief, though lengthy, review introduction about the long history
of higher order gravities and their applications, as employed in the
literature, is provided. We review the analogous procedure between higher order
gravities and GR, as described in our previous works, in order to highlight its
important achievements. Amongst which are presentation of an easy
classification of higher order Lagrangians and its employment as a
\emph{criteria} in order to distinguish correct metric theories of gravity. For
example, it does not permit the inclusion of only one of the second order
Lagrangians in \emph{isolation}. But, it does allow the inclusion of the
cosmological term. We also discuss on the compatibility of our procedure and
the Mach idea. We derive a dimensional dependent version of Duff's trace
anomaly relation, which in \emph{four}-dimension is the same as the usual Duff
relation. The Lanczos Lagrangian satisfies this new constraint in \emph{any}
dimension. The square of the Weyl tensor identically satisfies it independent
of dimension, however, this Lagrangian satisfies the previous relation only in
three and four dimensions.Comment: 30 pages, added reference
Decisions with Endogenous Frames (Replaces CentER DP 2010-21)
This paper contrasts the normative implications of a model of decision- making with endogenous frames to those of choice theoretic models of Bernheim and Rangel (2007, 2009) and Rubinstein and Salant (2008) in which observed choices are determined by exogenous frames or ancillary conditions. We argue that frames, though exogenous to the individual at the point when choices are made, matter for welfare purposes.Decisions;choice;frames;standard;behavioral;welfare
Black Hole Entropy and Quantum Gravity
An elementary introduction is given to the problem of black hole entropy as
formulated by Bekenstein and Hawking. The information theoretic basis of
Bekenstein's formulation is briefly reviewed and compared with Hawking's
approach. The issue of calculating the entropy by actual counting of
microstates is taken up next within two currently popular approaches to quantum
gravity, viz., string theory and canonical quantum gravity. The treatment of
the former assay is confined to a few remarks, mainly of a critical nature,
while some of the computational techniques of the latter approach are
elaborated. We conclude by trying to find commonalities between these two
rather disparate directions of work.Comment: 13 pages, Revtex, 5 eps figures. Invited talk at National Symposium
on Trends and Perspectives in Theoretical Physics, IACS, Calcutta, India,
April, 1998. One reference adde
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