Bulletin of the American Physical Society
2020 Annual Meeting of the APS Four Corners Section (Virtual)
Volume 65, Number 16
Friday–Saturday, October 23–24, 2020; Albuquerque, NM (Virtual)
Session L04: General Physics and Foundations of PhysicsLive
|
Hide Abstracts |
Chair: Sui Au Lee, Colorado State University |
Saturday, October 24, 2020 11:00AM - 11:12AM Live |
L04.00001: Electric Fields from Geometry Spencer Tamagni, Costas Efthimiou Using techniques from geometry and complex analysis in their simplest form, we present a derivation of electric fields on surfaces with non-trivial topology. A byproduct of this analysis is an intuitive visualization of elliptic functions when their argument is complex-valued. The underlying connections between these techniques and the theory of Riemann surfaces are also explained. Our goal is to provide students and instructors a quick reference article for an extraordinary topic that is not included in the standard books. [Preview Abstract] |
Saturday, October 24, 2020 11:12AM - 11:24AM Live |
L04.00002: Magnetic Forces without Magnetic Fields Michael Espinosa, James Espinosa Classical electromagnetism uses tensor fields to unite electricity and magnetism. Physicists like Gauss approached their studies of electrodynamics using an action at a distance formulation. Walter Ritz provided a tentative equation that embodied all of the positive aspects of Maxwell's equations while avoiding the self-contradictions and spurious predictions such as the ultraviolet catastrophe and the inability to provide a framework for atomic physics. We will introduce Ritz's theory using a simple example of an electron moving beside a neutral wire carrying a current and compare it to the Lorentz-Maxwell result. [Preview Abstract] |
Saturday, October 24, 2020 11:24AM - 11:36AM Live |
L04.00003: Electrostatic Fields without Excess Charges James Espinosa, James C. Espinosa One of the reasons that physicists in the late nineteenth century rejected using action at a distance in electromagnetism is the prediction of electrostatic fields produced by neutral currents. We will revisit this result and show that there is no experimental evidence to support this criticism. The theory of Walter Ritz will be used to calculate the force on a stationary charge a fixed distance from a neutral wire. The possibility of using this result to construct a classical model of the electron will also be explored. [Preview Abstract] |
Saturday, October 24, 2020 11:36AM - 11:48AM Live |
L04.00004: Piecemeal Model Reduction Benjamin Francis, Mark Transtrum Many systems can be modeled as a complicated network of interacting components. Often the level of detail in the model exceeds the richness of the available data, or makes the model computationally intensive to use or difficult to interpret. Such models can be improved by reducing their complexity. If a model of a network is very large, it may be desirable to split it into pieces and reduce them separately, recombining them after reduction. We discuss piecemeal reduction of a network in the context of the Manifold Boundary Approximation Method (MBAM), including its advantages over other reduction methods. We show that MBAM transforms the model reduction problem into one of selecting a model from a partially ordered set (poset). In some cases, the poset can be factored into components. This is equivalent to decomposing the model into pieces that can be reduced separately. We use this insight to propose a strategy for piecemeal reduction via MBAM. We demonstrate on a resistor network and show that MBAM finds a reduced model that introduces less bias than similar models with randomly selected reductions. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700