49 research outputs found
Revolutionizing physics: a comprehensive survey of machine learning applications
In the context of the 21st century and the fourth industrial revolution, the substantial proliferation of data has established it as a valuable resource, fostering enhanced computational capabilities across scientific disciplines, including physics. The integration of Machine Learning stands as a prominent solution to unravel the intricacies inherent to scientific data. While diverse machine learning algorithms find utility in various branches of physics, there exists a need for a systematic framework for the application of Machine Learning to the field. This review offers a comprehensive exploration of the fundamental principles and algorithms of Machine Learning, with a focus on their implementation within distinct domains of physics. The review delves into the contemporary trends of Machine Learning application in condensed matter physics, biophysics, astrophysics, material science, and addresses emerging challenges. The potential for Machine Learning to revolutionize the comprehension of intricate physical phenomena is underscored. Nevertheless, persisting challenges in the form of more efficient and precise algorithm development are acknowledged within this review
Markovian embedding of fractional superdiffusion
The Fractional Langevin Equation (FLE) describes a non-Markovian Generalized
Brownian Motion with long time persistence (superdiffusion), or
anti-persistence (subdiffusion) of both velocity-velocity correlations, and
position increments. It presents a case of the Generalized Langevin Equation
(GLE) with a singular power law memory kernel. We propose and numerically
realize a numerically efficient and reliable Markovian embedding of this
superdiffusive GLE, which accurately approximates the FLE over many, about r=N
lg b-2, time decades, where N denotes the number of exponentials used to
approximate the power law kernel, and b>1 is a scaling parameter for the
hierarchy of relaxation constants leading to this power law. Besides its
relation to the FLE, our approach presents an independent and very flexible
route to model anomalous diffusion. Studying such a superdiffusion in tilted
washboard potentials, we demonstrate the phenomenon of transient hyperdiffusion
which emerges due to transient kinetic heating effects.Comment: EPL, in pres
Knowledge Evolution in Physics Research: An Analysis of Bibliographic Coupling Networks
Even as we advance the frontiers of physics knowledge, our understanding of
how this knowledge evolves remains at the descriptive levels of Popper and
Kuhn. Using the APS publications data sets, we ask in this letter how new
knowledge is built upon old knowledge. We do so by constructing year-to-year
bibliographic coupling networks, and identify in them validated communities
that represent different research fields. We then visualize their evolutionary
relationships in the form of alluvial diagrams, and show how they remain intact
through APS journal splits. Quantitatively, we see that most fields undergo
weak Popperian mixing, and it is rare for a field to remain isolated/undergo
strong mixing. The sizes of fields obey a simple linear growth with
recombination. We can also reliably predict the merging between two fields, but
not for the considerably more complex splitting. Finally, we report a case
study of two fields that underwent repeated merging and splitting around 1995,
and how these Kuhnian events are correlated with breakthroughs on BEC, quantum
teleportation, and slow light. This impact showed up quantitatively in the
citations of the BEC field as a larger proportion of references from during and
shortly after these events.Comment: 14 pages, 14 figures, 1 tabl
Terwilliger in the department and university
The contributions of Kent Terwilliger to the University of Michigan are recalled. As associate chair for research and facilities, Kent managed funding for research, oversaw the department shops as well as performing several other tasks.(AIP)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87540/2/217_1.pd
Gap and out-gap breathers in a binary modulated discrete nonlinear Schr\"odinger model
We consider a modulated discrete nonlinear Schr\"odinger (DNLS) model with
alternating on-site potential, having a linear spectrum with two branches
separated by a 'forbidden' gap. Nonlinear localized time-periodic solutions
with frequencies in the gap and near the gap -- discrete gap and out-gap
breathers (DGBs and DOGBs) -- are investigated. Their linear stability is
studied varying the system parameters from the continuous to the
anti-continuous limit, and different types of oscillatory and real
instabilities are revealed. It is shown, that generally DGBs in infinite
modulated DNLS chains with hard (soft) nonlinearity do not possess any
oscillatory instabilities for breather frequencies in the lower (upper) half of
the gap. Regimes of 'exchange of stability' between symmetric and antisymmetric
DGBs are observed, where an increased breather mobility is expected. The
transformation from DGBs to DOGBs when the breather frequency enters the linear
spectrum is studied, and the general bifurcation picture for DOGBs with tails
of different wave numbers is described. Close to the anti-continuous limit, the
localized linear eigenmodes and their corresponding eigenfrequencies are
calculated analytically for several gap/out-gap breather configurations,
yielding explicit proof of their linear stability or instability close to this
limit.Comment: 17 pages, 12 figures, submitted to Eur. Phys. J.
The quest and hope of Majorana zero modes in topological superconductor for fault-tolerant quantum computing: an introductory overview
Ettore Majorana, in his short life, unintendedly has uncovered the most
profound problem in quantum computation by his discovery of Majorana fermion, a
particle which is its own anti-particle. Owing to its non-Abelian exchange
statistics, Majorana fermions may act as a qubit for a universal quantum
computer which is fault-tolerant. The existence of such particle is predicted
in mid-gap states (zero modes) of a topological superconductor as bound states
that have a highly entangled degenerate ground state. This introductory
overview will focus on the simplest theoretical proposals of Majorana fermions
for topological quantum computing in superconducting systems, emphasizing the
quest from the scalability problem of quantum computer to its possible solution
with topological quantum computer employing non-Abelian anyons on various
platforms of certain Majorana fermion signature encountered.Comment: 18 pages, 3 figures, The 4th International Seminar on Metallurgy and
Materials (ISMM) 2020 Indonesian Institute of Sciences; typos correcte
Washington University Record, November 30, 2006
https://digitalcommons.wustl.edu/record/2091/thumbnail.jp