510 research outputs found
Quantum Electrodynamics at Large Distances II: Nature of the Dominant Singularities
Accurate calculations of macroscopic and mesoscopic properties in quantum
electrodynamics require careful treatment of infrared divergences: standard
treatments introduce spurious large-distances effects. A method for computing
these properties was developed in a companion paper. That method depends upon a
result obtained here about the nature of the singularities that produce the
dominant large-distance behaviour. If all particles in a quantum field theory
have non-zero mass then the Landau-Nakanishi diagrams give strong conditions on
the singularities of the scattering functions. These conditions are severely
weakened in quantum electrodynamics by effects of points where photon momenta
vanish. A new kind of Landau-Nakanishi diagram is developed here. It is geared
specifically to the pole-decomposition functions that dominate the macroscopic
behaviour in quantum electrodynamics, and leads to strong results for these
functions at points where photon momenta vanish.Comment: 40 pages, 11 encapsulated postscript figures, latexed,
math_macros.tex can be found on Archive. full postscript available from
http://theorl.lbl.gov/www/theorgroup/papers/35972.p
On the Consequences of Retaining the General Validity of Locality in Physical Theory
The empirical validity of the locality (LOC) principle of relativity is used
to argue in favour of a local hidden variable theory (HVT) for individual
quantum processes. It is shown that such a HVT may reproduce the statistical
predictions of quantum mechanics (QM), provided the reproducibility of initial
hidden variable states is limited. This means that in a HVT limits should be
set to the validity of the notion of counterfactual definiteness (CFD). This is
supported by the empirical evidence that past, present, and future are
basically distinct. Our argumentation is contrasted with a recent one by Stapp
resulting in the opposite conclusion, i.e. nonlocality or the existence of
faster-than-light influences. We argue that Stapp's argumentation still depends
in an implicit, but crucial, way on both the notions of hidden variables and of
CFD. In addition, some implications of our results for the debate between Bohr
and Einstein, Podolsky and Rosen are discussed.Comment: revtex, 11 page
Recommended from our members
Pacifc Northwest Archaeological Society (PNWAS): Reaching the Northwest Advocational Public for 36 Years
This paper is Chapter 3, pp. 35-45, of a 275+ page volume on How do we Reach More?; a free source book on trying to reach the public in the Pacific Northwest of North America: https://www.northwestanthropology.com/how-do-we-reach-more This book is freely available for those that want to see what tended to work or not work in this effort. Since PNWAS has been around for 36 years, a certain amount of success is demonstrated, including activism possible through a non-profit for education program. Abstract for Pacific Northwest Archaeological Society (PNWAS) chapter 3: As originally stated in our founding in 1985, PNWAS is a membership organization that “offers a means for individuals and organizations to declare their support for the preservation of the rich archaeological resources in our region and help to bring public archaeology programs to people of the Pacific Northwest. Benefits of membership include timely information on Northwest archaeological research, a bi-monthly lecture series, and opportunity to participate in professionally supervised research in the Northwest.” PNWAS was incorporated at that time as a non-profit organization in the State of Washington and has remained true to these original objectives. I have been the Executive Director throughout these 36 years, with a President, Vice-President, and other Officers on our Board
Recommended from our members
Generationally-Linked Archaeology
The research involved the efforts of a wet archaeological site specialist (Dale Croes) and a Master Basketmaker and Elder from the Suquamish Tribe (Ed Carriere), who joined together to replicate and scientifically analyze the 2,000-year-old basketry collection from the Biderbost wet site, Snoqualmie Tribal Territory, housed at the University of Washington (UW) Burke Museum Archaeology Program (Figure 1). Working on this analysis and replication project over the past four years, we concluded that it was not enough to call this a case of Experimental Archaeology; we describe our work as a new approach termed Generationally-Linked Archaeology, an approach that chronologically connects from both directions, linking contemporary cultural specialists with ancient and ancestral basketmakers through the science of archaeology. We present our approach here after publicly presenting our efforts to both indigenous and scientific archaeological audiences, including Native peoples at the Northwest Native American Basketweavers Association, Indigenous Ainu of northern Japan, and at a National Maori Weavers conference in New Zealand, and to archaeological scientists at two annual SAA conferences, the Wetland Archaeological Research Project (WARP) 30th Anniversary Conference in Bradford, England, and a Wetland Archaeology Conference in central France
On Quantum Jumps, Events and Spontaneous Localization Models
We propose a definite meaning to the concepts of "experiment", "measurement"
and "event" in the event-enhanced formalism of quantum theory. A minimal
piecewise deterministic process is given that can be used for a computer
simulation of real time series of experiments on single quantum objects. As an
example a generalized cloud chamber is described, including multiparticle case.
Relation to the GRW spontaneous localization model is discussed. The second
revised version of the paper contains references to papers by other authors
that are are aiming in the same direction: to enhance quantum theory in such a
way that it will provide stochastic description of events triggered by
individual quantum systems.Comment: 20 page
Integrating Indigenous Values into Federal Agency Impact Assessments to Reduce Conflicts—A Role for Anthropologists
Conflicts surrounding the development of public lands are on the rise around the world. In the United States, where laws require federal agencies to conduct environmental and cultural impact assessments before approving or permitting development projects, conflicts still occur. This is especially true for projects that impact indigenous lands, resources, and communities, as the recent controversy surrounding Dakota Access Pipeline project so well illustrates. The purpose of this article is to highlight some of the problems I have encountered as an anthropologist conducting cultural impact assessments for federal agencies and for indigenous communities. Central among the problems encountered are the lack of awareness and appreciation for indigenous values by project proponents, agencies, and sometimes even the analysts hired to conduct the assessments. Recommendations for improving the quality of cultural impact assessments, which are based on the tenets of Action Anthropology, are explained
A Lens With Multiple Perspectives: The Transformative Power of Higher Education in Health Promotion
According to the Centers for Disease Control and Prevention, chronic conditions represent the largest risk to America’s health (Centers for Disease Control and Prevention [CDC], 2013). Approximately 50% of adults are affected by at least one chronic disease and 25% of adults are affected by more than two (CDC, 2013). As this health crisis expands, those who have the power to create change must utilize it to their highest capacity. While the complexities of the current state of health are challenging, higher education provides a powerful platform wherein those intricacies can be fully examined and resolutions sought through multiple lenses. This essay provides an example of how both individual and collaborative endeavors have been fostered at the University of Mississippi to generate local, national, and global transformations in health
Bell inequalities for continuous-variable correlations
We derive a new class of correlation Bell-type inequalities. The inequalities
are valid for any number of outcomes of two observables per each of n parties,
including continuous and unbounded observables. We show that there are no
first-moment correlation Bell inequalities for that scenario, but such
inequalities can be found if one considers at least second moments. The
derivation stems from a simple variance inequality by setting local commutators
to zero. We show that above a constant detector efficiency threshold, the
continuous variable Bell violation can survive even in the macroscopic limit of
large n. This method can be used to derive other well-known Bell inequalities,
shedding new light on the importance of non-commutativity for violations of
local realism.Comment: 4 pages, 1 figure. v2: New results on detector efficiencies and
macroscopic limit, new co-author, changed title and abstract, changed figure,
added journal reference and DO
Einstein-Podolsky-Rosen paradox without entanglement
We claim that the nonlocality without entanglement revealed quite recently by
Bennett {\it et al.} [quant-ph/9804053] should be rather interpreted as {\it
Einstein-Podolsky-Rosen paradox without entanglement}. It would be true
nonlocality without entanglement if one knew that quantum mechnics provides the
best possible means for extracting information from physical system i.e. that
it is ``operationally complete''.Comment: RevTeX, 2 page
Free Will in a Quantum World?
In this paper, I argue that Conway and Kochen’s Free Will Theorem (1,2) to the conclusion that quantum mechanics and relativity entail freedom for the particles, does not change the situation in favor of a libertarian position as they would like. In fact, the theorem more or less implicitly assumes that people are free, and thus it begs the question. Moreover, it does not prove neither that if people are free, so are particles, nor that the property people possess when they are said to be free is the same as the one particles possess when they are claimed to be free. I then analyze the Free State Theorem (2), which generalizes the Free Will Theorem without the assumption that people are free, and I show that it does not prove anything about free will, since the notion of freedom for particles is either inconsistent, or it does not concern our common understanding of freedom. In both cases, the Free Will Theorem and the Free State Theorem do not provide any enlightenment on the constraints physics can pose on free will
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