Open Access. Powered by Scholars. Published by Universities.^{®}
 Discipline

 Statistical, Nonlinear, and Soft Matter Physics (10)
 Biochemistry, Biophysics, and Structural Biology (6)
 Life Sciences (6)
 Biological and Chemical Physics (6)
 Quantum Physics (6)

 Mathematics (5)
 Condensed Matter Physics (3)
 Statistics and Probability (3)
 Chemistry (3)
 Physical Chemistry (3)
 Arts and Humanities (2)
 Cosmology, Relativity, and Gravity (2)
 Astrophysics and Astronomy (2)
 Other Biochemistry, Biophysics, and Structural Biology (2)
 Engineering (2)
 Nonlinear Dynamics (1)
 Engineering Science and Materials (1)
 Applied Mathematics (1)
 Philosophy (1)
 Biophysics (1)
 Electrical and Computer Engineering (1)
 Economic Theory (1)
 Philosophy of Science (1)
 Economics (1)
 Dynamics and Dynamical Systems (1)
 History (1)
 Number Theory (1)
 History of Science, Technology, and Medicine (1)
 Institution
 Publication Year
 Publication

 Physics (8)
 Dartmouth Scholarship (7)
 Scholar Archive (6)
 Physics Faculty Research & Creative Works (6)
 Physics Faculty Publications and Presentations (5)

 Electrical & Computer Engineering Faculty Publications (2)
 Electronic Theses and Dissertations, 20042019 (2)
 Faculty Scholarship for the College of Science & Mathematics (2)
 Graduate College Dissertations and Theses (2)
 Honors Theses (1)
 Mathematics Publications (1)
 Many Particles (1)
 Mathematics, Physics, and Computer Science Faculty Articles and Research (1)
 Graduate Theses and Dissertations (1)
 David D Nolte (1)
 Physics Faculty Publications (1)
 Publications and Research (1)
 Electronic Theses and Dissertations (1)
 Mathematics & Statistics Faculty Publications (1)
 Trevor I. Smith (1)
 Publication Type
 File Type
Articles 1  30 of 51
FullText Articles in Physics
LinkedCluster Expansions For Lattice Spin Models, Yuyi Wan
LinkedCluster Expansions For Lattice Spin Models, Yuyi Wan
Honors Theses
Similar to various series expansions that are used to approximate mathematical func tions, the linkedcluster expansion is an approximation method that allows us to approach the actual values of a very large physical system’s different physical quan tities by systematically studying smaller systems embedded in this larger system. The main concept in linkedcluster expansion, weight, represents the additional con tribution to a certain physical quantity by increasing the system size by one unit. These weights are used to eventually build up the result on a larger system. In our case, we focus on the partition function, a quantity that ...
An Application Of The Ising Model, Juliano A. Everett
An Application Of The Ising Model, Juliano A. Everett
Publications and Research
Understanding how the Ising model works,what it represents, and how it can be applied to neurology. Given that an Ising model is an Entropy model that could be representative of the firing of neurons, some assumptions of the system are made and then the process is simulated through Monte Carlo methods.
InfiniteRandomness Fixed Point Of The Quantum SuperconductorMetal Transitions In Amorphous Thin Films, Nicholas A. Lewellyn, Ilana M. Percher, J. J. Nelson, Javier GarciaBarriocanal, Irina Volotsenko, Aviad Frydman, Thomas Vojta, Allen M. Goldman
InfiniteRandomness Fixed Point Of The Quantum SuperconductorMetal Transitions In Amorphous Thin Films, Nicholas A. Lewellyn, Ilana M. Percher, J. J. Nelson, Javier GarciaBarriocanal, Irina Volotsenko, Aviad Frydman, Thomas Vojta, Allen M. Goldman
Physics Faculty Research & Creative Works
The magneticfieldtuned quantum superconductorinsulator transitions of disordered amorphous indium oxide films are a paradigm in the study of quantum phase transitions and exhibit powerlaw scaling behavior. For superconducting indium oxide films with low disorder, such as the ones reported on here, the highfield state appears to be a quantumcorrected metal. Resistance data across the superconductormetal transition in these films are shown here to obey an activated scaling form appropriate to a quantum phase transition controlled by an infiniterandomness fixed point in the universality class of the random transversefield Ising model. Collapse of the fielddependent resistance vs temperature data is obtained ...
Universality Class Of Explosive Percolation In BarabásiAlbert Networks, Habib E. Islam, M. K. Hassan
Universality Class Of Explosive Percolation In BarabásiAlbert Networks, Habib E. Islam, M. K. Hassan
Physics Faculty Publications
In this work, we study explosive percolation (EP) in BarabásiAlbert (BA) network, in which nodes are born with degree k = m, for both product rule (PR) and sum rule (SR) of the Achlioptas process. For m = 1 we find that the critical point t_{c} = 1 which is the maximum possible value of the relative link density t; Hence we cannot have access to the other phase like percolation in one dimension. However, for m > 1 we find that t_{c} decreases with increasing m and the critical exponents ν, α, β and γ for m > 1 are found to ...
Some Results On A Class Of Functional Optimization Problems, David Rushing Dewhurst
Some Results On A Class Of Functional Optimization Problems, David Rushing Dewhurst
Graduate College Dissertations and Theses
We first describe a general class of optimization problems that describe many natu ral, economic, and statistical phenomena. After noting the existence of a conserved quantity in a transformed coordinate system, we outline several instances of these problems in statistical physics, facility allocation, and machine learning. A dynamic description and statement of a partial inverse problem follow. When attempting to optimize the state of a system governed by the generalized equipartitioning princi ple, it is vital to understand the nature of the governing probability distribution. We show that optimiziation for the incorrect probability distribution can have catas trophic results, e ...
Statistical Biophysics Blog: Let’S Stop Being Sloppy About Uncertainty, Daniel M. Zuckerman
Statistical Biophysics Blog: Let’S Stop Being Sloppy About Uncertainty, Daniel M. Zuckerman
Scholar Archive
Molecular dynamics simulations often fail to reach timescales characteristic of equilibrum sampling, so great care must be taken in computing and reporting statistical uncertainty.
Student Understanding Of Taylor Series Expansions In Statistical Mechanics, Trevor I. Smith, John R. Thompson, Donald B. Mountcastle
Student Understanding Of Taylor Series Expansions In Statistical Mechanics, Trevor I. Smith, John R. Thompson, Donald B. Mountcastle
Trevor I. Smith
One goal of physics instruction is to have students learn to make physical meaning of specific mathematical expressions, concepts, and procedures in different physical settings. As part of research investigating student learning in statistical physics, we are developing curriculum materials that guide students through a derivation of the Boltzmann factor using a Taylor series expansion of entropy. Using results from written surveys, classroom observations, and both individual thinkaloud and teaching interviews, we present evidence that many students can recognize and interpret series expansions, but they often lack fluency in creating and using a Taylor series appropriately, despite previous exposures in ...
ManyParticle Systems, 3, David Peak
ManyParticle Systems, 3, David Peak
Many Particles
Bare essentials of statistical mechanics
Atoms are examples of manyparticle systems, but atoms are extraordinarily simpler than macroscopic systems consisting of 10^{20}10^{30} atoms. Despite their great size, many properties of macroscopic systems depend intimately on the microscopic behavior of their microscopic constituents. The proper quantum mechanical description of an N particle system is a wavefunction that depends on 3N coordinates (3 ways of moving, in general, for every particle) and 4N quantum numbers (3 motional quantum numbers and 1 spin quantum number for every particle). (If the “particles” are molecules there might be additional quantum ...
Statistical Biophysics Blog: What I Have Against (Most) Pmf Calculations, Daniel M. Zuckerman
Statistical Biophysics Blog: What I Have Against (Most) Pmf Calculations, Daniel M. Zuckerman
Scholar Archive
The potential of mean force (PMF) is one of the most widely used characterizations of a biomolecular system computed from simulation, but calculating and interpreting a PMF both present challenges.
Dynamical Mechanisms Leading To Equilibration In TwoComponent Gases, Stephan De Bievre, Carlos MejiaMonasterio, Paul Ernest Parris
Dynamical Mechanisms Leading To Equilibration In TwoComponent Gases, Stephan De Bievre, Carlos MejiaMonasterio, Paul Ernest Parris
Physics Faculty Research & Creative Works
Demonstrating how microscopic dynamics cause large systems to approach thermal equilibrium remains an elusive, longstanding, and actively pursued goal of statistical mechanics. We identify here a dynamical mechanism for thermalization in a general class of twocomponent dynamical Lorentz gases and prove that each component, even when maintained in a nonequilibrium state itself, can drive the other to a thermal state with a welldefined effective temperature.
Statistical Biophysics Blog: So You Want To Do Some Path Sampling …, Daniel M. Zuckerman
Statistical Biophysics Blog: So You Want To Do Some Path Sampling …, Daniel M. Zuckerman
Scholar Archive
Basic concepts and limitations of path sampling are described.
Statistical Biophysics Blog: Faq On Trajectory Ensembles, Daniel M. Zuckerman
Statistical Biophysics Blog: Faq On Trajectory Ensembles, Daniel M. Zuckerman
Scholar Archive
The basics of trajectories and the different types of trajectory ensembles are explained.
Effective Microscopic Models For Sympathetic Cooling Of Atomic Gases, Roberto Onofrio, Bala Sundaram
Effective Microscopic Models For Sympathetic Cooling Of Atomic Gases, Roberto Onofrio, Bala Sundaram
Dartmouth Scholarship
Thermalization of a system in the presence of a heat bath has been the subject of many theoretical investigations especially in the framework of solidstate physics. In this setting, the presence of a large bandwidth for the frequency distribution of the harmonic oscillators schematizing the heat bath is crucial, as emphasized in the CaldeiraLeggett model. By contrast, ultracold gases in atomic traps oscillate at welldefined frequencies and therefore seem to lie outside the CaldeiraLeggett paradigm. We introduce interaction Hamiltonians which allow us to adapt the model to an atomic physics framework. The intrinsic nonlinearity of these models differentiates them from ...
Student Understanding Of The Boltzmann Factor, Trevor I. Smith, Donald B. Mountcastle, John R. Thompson
Student Understanding Of The Boltzmann Factor, Trevor I. Smith, Donald B. Mountcastle, John R. Thompson
Faculty Scholarship for the College of Science & Mathematics
We present results of our investigation into student understanding of the physical significance and utility of the Boltzmann factor in several simple models. We identify various justifications, both correct and incorrect, that students use when answering written questions that require application of the Boltzmann factor. Results from written data as well as teaching interviews suggest that many students can neither recognize situations in which the Boltzmann factor is applicable nor articulate the physical significance of the Boltzmann factor as an expression for multiplicity, a fundamental quantity of statistical mechanics. The specific student difficulties seen in the written data led us ...
Statistical Biophysics Blog: More Is Better: The Trajectory Ensemble Picture, Daniel M. Zuckerman
Statistical Biophysics Blog: More Is Better: The Trajectory Ensemble Picture, Daniel M. Zuckerman
Scholar Archive
The trajectory ensemble is fundamental in statistical physics and relatively easy to understand. It is also informationrich, as both equilibrium and nonequilibrium observables may be derived from it.
Statistical Biophysics Blog: A Hello: The Point Of This Blog, Daniel M. Zuckerman
Statistical Biophysics Blog: A Hello: The Point Of This Blog, Daniel M. Zuckerman
Scholar Archive
No abstract provided.
Spatiotemporally Periodic Driven System With LongRange Interactions, Owen Dale Myers
Spatiotemporally Periodic Driven System With LongRange Interactions, Owen Dale Myers
Graduate College Dissertations and Theses
It is well known that some driven systems undergo transitions when a system parameter is changed adiabatically around a critical value. This transition can be the result of a fundamental change in the structure of the phase space, called a bifurcation. Most of these transitions are well classified in the theory of bifurcations. Among the driven systems, spatiotemporally periodic (STP) potentials are noteworthy due to the intimate coupling between their time and spatial components. A paradigmatic example of such a system is the Kapitza pendulum, which is a pendulum with an oscillating suspension point. The Kapitza pendulum has the strange ...
Theoretical And Numerican Studies Of Phase Transitions And Error Thresholds In Topological Quantum Memories, Pejman Jouzdani
Theoretical And Numerican Studies Of Phase Transitions And Error Thresholds In Topological Quantum Memories, Pejman Jouzdani
Electronic Theses and Dissertations, 20042019
This dissertation is the collection of a progressive research on the topic of topological quantum computation and information with the focus on the error threshold of the wellknown models such as the unpaired Majorana, the toric code, and the planar code. We study the basics of quantum computation and quantum information, and in particular quantum error correction. Quantum error correction provides a tool for enhancing the quantum computation fidelity in the noisy environment of a real world. We begin with a brief introduction to stabilizer codes. The stabilizer formalism of the theory of quantum error correction gives a welldefined description ...
Modeling The Interaction Of Complex Networks, Wenjia Liu
Modeling The Interaction Of Complex Networks, Wenjia Liu
Graduate Theses and Dissertations
Many specific networks (e.g., internet, power grid, interstates), have been characterized well, but in isolation from one another. Yet, in the real world, different networks support each other's functions, and so far, little is known about how their interactions affect their structure and functionality. To address this issue, we introduce a stochastically evolving network, namely a preferred degree network, and study the interactions between such two networks. First, a homogeneous preferred degree network is studied. The resultant degree distribution is consistent with a Laplacian distribution, and an approximate theory provides good explanations. Second, another preferred degree network is ...
Student Understanding Of Taylor Series Expansions In Statistical Mechanics, Trevor I. Smith, John R. Thompson, Donald B. Mountcastle
Student Understanding Of Taylor Series Expansions In Statistical Mechanics, Trevor I. Smith, John R. Thompson, Donald B. Mountcastle
Faculty Scholarship for the College of Science & Mathematics
One goal of physics instruction is to have students learn to make physical meaning of specific mathematical expressions, concepts, and procedures in different physical settings. As part of research investigating student learning in statistical physics, we are developing curriculum materials that guide students through a derivation of the Boltzmann factor using a Taylor series expansion of entropy. Using results from written surveys, classroom observations, and both individual thinkaloud and teaching interviews, we present evidence that many students can recognize and interpret series expansions, but they often lack fluency in creating and using a Taylor series appropriately, despite previous exposures in ...
Disordered Bosons In One Dimension: From Weak To StrongRandomness Criticality, Fawaz Hrahsheh, Thomas Vojta
Disordered Bosons In One Dimension: From Weak To StrongRandomness Criticality, Fawaz Hrahsheh, Thomas Vojta
Physics Faculty Research & Creative Works
We investigate the superfluidinsulator quantum phase transition of onedimensional bosons with offdiagonal disorder by means of largescale Monte Carlo simulations. For weak disorder, we find the transition to be in the same universality class as the superfluidMott insulator transition of the clean system. The nature of the transition changes for stronger disorder. Beyond a critical disorder strength, we find nonuniversal, disorderdependent critical behavior. We compare our results to recent perturbative and strongdisorder renormalization group predictions. We also discuss experimental implications as well as extensions of our results to other systems.
Information Content Of Spontaneous Symmetry Breaking, Marcelo Gleiser, Nikitas Stamatopoulos
Information Content Of Spontaneous Symmetry Breaking, Marcelo Gleiser, Nikitas Stamatopoulos
Dartmouth Scholarship
We propose a measure of order in the context of nonequilibrium field theory and argue that this measure, which we call relative configurational entropy (RCE), may be used to quantify the emergence of coherent lowentropy configurations, such as timedependent or timeindependent topological and nontopological spatially extended structures. As an illustration, we investigate the nonequilibrium dynamics of spontaneous symmetry breaking in three spatial dimensions. In particular, we focus on a model where a real scalar field, prepared initially in a symmetric thermal state, is quenched to a brokensymmetric state. For a certain range of initial temperatures, spatially localized, longlived structures known ...
Everything Is Entangled, Roman V. Buniy, Stephen D. H. Hsu
Everything Is Entangled, Roman V. Buniy, Stephen D. H. Hsu
Mathematics, Physics, and Computer Science Faculty Articles and Research
We show that big bang cosmology implies a high degree of entanglement of particles in the universe. In fact, a typical particle is entangled with many particles far outside our horizon. However, the entanglement is spread nearly uniformly so that two randomly chosen particles are unlikely to be directly entangled with each other  the reduced density matrix describing any pair is likely to be separable.
MotorDriven Dynamics Of Cytoskeletal Filaments In Motility Assays, Shiladitya Banerjee, M. Cristina Marchetti, Kristian MullerNedebock
MotorDriven Dynamics Of Cytoskeletal Filaments In Motility Assays, Shiladitya Banerjee, M. Cristina Marchetti, Kristian MullerNedebock
Physics
We model analytically the dynamics of a cytoskeletal filament in a motility assay. The filament is described as rigid rod free to slide in two dimensions. The motor proteins consist of polymeric tails tethered to the plane and modeled as linear springs and motor heads that bind to the filament. As in related models of rigid and soft twostate motors, the binding/unbinding dynamics of the motor heads and the dependence of the transition rates on the load exerted by the motor tails play a crucial role in controlling the filament's dynamics. Our work shows that the filament effectively ...
Evidence For PowerLaw Griffiths Singularities In A Layered Heisenberg Magnet, Fawaz Hrahsheh, Hatem Barghathi, Priyanka Mohan, Rajesh Narayanan, Thomas Vojta
Evidence For PowerLaw Griffiths Singularities In A Layered Heisenberg Magnet, Fawaz Hrahsheh, Hatem Barghathi, Priyanka Mohan, Rajesh Narayanan, Thomas Vojta
Physics Faculty Research & Creative Works
We study the ferromagnetic phase transition in a randomly layered Heisenberg model. A recent strongdisorder renormalization group approach [Phys. Rev. B 81, 144407 (2010)] predicted that the critical point in this system is of exotic infiniterandomness type and is accompanied by strong powerlaw Griffiths singularities. Here, we report results of MonteCarlo simulations that provide numerical evidence in support of these predictions. Specifically, we investigate the finitesize scaling behavior of the magnetic susceptibility which is characterized by a nonuniversal powerlaw divergence in the Griffiths phase. In addition, we calculate the time autocorrelation function of the spins. It features a very slow ...
Dynamical Critical Scaling And Effective Thermalization In Quantum Quenches: Role Of The Initial State, Shusa Deng, Gerardo Ortiz, Lorenza Viola
Dynamical Critical Scaling And Effective Thermalization In Quantum Quenches: Role Of The Initial State, Shusa Deng, Gerardo Ortiz, Lorenza Viola
Dartmouth Scholarship
We explore the robustness of universal dynamical scaling behavior in a quantum system near criticality with respect to initialization in a large class of states with finite energy. By focusing on a homogeneous XY quantum spin chain in a transverse field, we characterize the nonequilibrium response under adiabatic and sudden quench processes originating from a pure as well as a mixed excited initial state, and involving either a regular quantum critical or a multicritical point. We find that the critical exponents of the groundstate quantum phase transition can be encoded in the dynamical scaling exponents despite the finite energy of ...
UnitaryQuantumLattice Algorithm For TwoDimensional Quantum Turbulence, Bo Zhang, George Vahala, Linda L. Vahala, Min Soe
UnitaryQuantumLattice Algorithm For TwoDimensional Quantum Turbulence, Bo Zhang, George Vahala, Linda L. Vahala, Min Soe
Electrical & Computer Engineering Faculty Publications
Quantum vortex structures and energy cascades are examined for twodimensional quantum turbulence (2D QT) at zero temperature. A special unitary evolution algorithm, the quantum lattice algorithm, is employed to simulate the BoseEinstein condensate governed by the GrossPitaevskii (GP) equation. A parameter regime is uncovered in which, as in 3D QT, there is a short Poincare recurrence time. It is demonstrated that such short recurrence times are destroyed by stronger nonlinear interaction. The similar loss of Poincare recurrence is also seen in the 3D GP equation. Various initial conditions are considered in an attempt to discern if 2D QT exhibits inverse ...
Poincare Recurrence And Spectral Cascades In ThreeDimensional Quantum Turbulence, George Vahala, Jeffrey Yepez, Linda L. Vahala, Min Soe, Bo Zhang, Sean Ziegeler
Poincare Recurrence And Spectral Cascades In ThreeDimensional Quantum Turbulence, George Vahala, Jeffrey Yepez, Linda L. Vahala, Min Soe, Bo Zhang, Sean Ziegeler
Electrical & Computer Engineering Faculty Publications
The time evolution of the ground state wave function of a zerotemperature BoseEinstein condensate (BEC) gas is well described by the Hamiltonian GrossPitaevskii (GP) equation. Using a set of appropriately interleaved unitary collisionstream operators, a qubit lattice gas algorithm is devised, which on taking moments, recovers the GrossPitaevskii (GP) equation under diffusion ordering (time scales as length^{2}). Unexpectedly, there is a class of initial states whose Poincaré recurrence time is extremely short and which, as the grid resolution is increased, scales with diffusion ordering (and not as length^{3}). The spectral results of J. Yepez et al. [Phys. Rev ...
Dynamical Conductivity At The Dirty SuperconductorMetal Quantum Phase Transition, Adrian Del Maestro, Bernd Rosenow, Jose A. Hoyos, Thomas Vojta
Dynamical Conductivity At The Dirty SuperconductorMetal Quantum Phase Transition, Adrian Del Maestro, Bernd Rosenow, Jose A. Hoyos, Thomas Vojta
Physics Faculty Research & Creative Works
We study the transport properties of ultrathin disordered nanowires in the neighborhood of the superconductormetal quantum phase transition. To this end we combine numerical calculations with analytical strongdisorder renormalization group results. The quantum critical conductivity at zero temperature diverges logarithmically as a function of frequency. In the metallic phase, it obeys activated scaling associated with an infiniterandomness quantum critical point. We extend the scaling theory to higher dimensions and discuss implications for experiments.
Fluctuations And Pattern Formation In SelfPropelled Particles, Shradha Mishra, Aparna Baskaran, M. Cristina Marchetti
Fluctuations And Pattern Formation In SelfPropelled Particles, Shradha Mishra, Aparna Baskaran, M. Cristina Marchetti
Physics
We consider a coarsegrained description of a system of selfpropelled particles given by hydrodynamic equations for the density and polarization fields. We find that the ordered moving or flocking state of the system is unstable to spatial fluctuations beyond a threshold set by the selfpropulsion velocity of the individual units. In this region, the system organizes itself into an inhomogeneous state of welldefined propagating stripes of flocking particles interspersed with low density disordered regions. Further, we find that even in the regime where the homogeneous flocking state is stable, the system exhibits large fluctuations in both density and orientational order ...