41,602 research outputs found
Predicting the relativistic periastron advance of a binary without curving spacetime
Relativistic Newtonian Dynamics, the simple model used previously for
predicting accurately the anomalous precession of Mercury, is now applied to
predict the periastron advance of a binary. The classical treatment of a binary
as a two-body problem is modified to account for the influence of the
gravitational potential on spacetime. Without curving spacetime, the model
predicts the identical equation for the relativistic periastron advance as the
post-Newtonian approximation of general relativity formalism thereby providing
further substantiation of this model.Comment: 6 pages, 2 figure
The scalar complex potential and the Aharonov-Bohm effect
The Aharonov-Bohm effect is traditionally attributed to the effect of the
electromagnetic 4-potential , even in regions where both the electric field
and the magnetic field are zero. The AB effect
reveals that multiple-valued functions play a crucial role in the description
of an electromagnetic field. We argue that the quantity measured by AB
experiments is a difference in values of a multiple-valued complex function,
which we call a complex potential or {pre-potential. We show that any
electromagnetic field can be described by this pre-potential, and give an
explicit expression for the electromagnetic field tensor through this
potential. The pre-potential is a modification of the two scalar potential
functions.Comment: 10 pages 2 figure
Experience in feeding coal into a liquefaction process development unit
A system for preparing coal slurry and feeding it into a high pressure liquefaction plant is described. The system was developed to provide supporting research and development for the Bureau of Mines coal liquefaction pilot plant. Operating experiences are included
The structural contradictions and constraints on corporate social responsibility: Challenges for corporate social irresponsibility
Purpose - This chapter engages critically with the ideas of corporate social responsibility (CSR) and irresponsibility (CSI) in order to examine their utility for the purposes of realizing more socially just and environmentally sustainable social and economic practices. Methodology/approach - The chapter develops Marx's understanding of the twin pressures of class struggle and inter-capitalist competition in setting the limits of agency for corporate actors. It is thus theoretical and discursive in nature. Findings - The findings of the chapter suggest that the scope for corporate agency in relation to responsibility/irresponsibility is severely limited by inter-capitalist competition and capitalist social relations. It therefore argues that those interested in social justice and environmental sustainability should focus on these structural pressures rather than theorizing corporate agency. Social implications - The research suggests that the focus of academic and government attention should be on resolving the contradictions and exploitative social relations inherent in capitalism. Without this emphasis activism, corporate agency and government action will not eradicate the types of problem that advocates of CSR/CSI are concerned about. Originality/value of paper - The value of the paper is that it contests and engages critically with the utility of the notion of CSR and the emergent concept of CSI. It asks proponents of these concepts to think seriously about the structural pressures and constraints within which business and policy makers act. Copyrightr © 2012 by Emerald Group Publishing Limited
Financial Crises: Recent Experience in U.S. and International Markets
macroeconomics, financial crisis, crises, U.S. markets, international markets
Future directions in kaonic atom physics
Recent progress and open problems in kaonic atom physics are presented. A
connection between phenomenological deep potentials and the underlying
interaction is established as well as the need for a theory for multinucleon
absorption of kaons. absorption at rest to specific
hypernuclei states is briefly discussed.Comment: 6 pages, 3 figures, proceedings of the EXA2011 conference, to appear
in Hyperfine Interaction
The time travel paradox
We define the time travel paradox in physical terms and prove its existence
by constructing an explicit example. We argue further that in theories -- such
as general relativity -- where the spacetime geometry is subject to nothing but
differential equations and initial data no paradoxes arise.Comment: Minor changes + an explanatory note concerning the lions with the
same world line
Quasi-Adiabatic Continuation in Gapped Spin and Fermion Systems: Goldstone's Theorem and Flux Periodicity
We apply the technique of quasi-adiabatic continuation to study systems with
continuous symmetries. We first derive a general form of Goldstone's theorem
applicable to gapped nonrelativistic systems with continuous symmetries. We
then show that for a fermionic system with a spin gap, it is possible to insert
-flux into a cylinder with only exponentially small change in the energy
of the system, a scenario which covers several physically interesting cases
such as an s-wave superconductor or a resonating valence bond state.Comment: 19 pages, 2 figures, final version in press at JSTA
- …