Center for Soft Matter and Biological Physics Friday Discussion Meetings

Spring 2018

Organizer: Vinh Nguyen

These meetings occur on Fridays from 4:00pm to 5:00pm in Robeson 304 (unless otherwise indicated)

January 2018
January 5

Friday 4:00pm
304 Robeson Hall
(poster)

"No CSB Discussion Meeting Scheduled"

Organizer: Vinh Nguyen

January 12

Friday 4:00pm
304 Robeson Hall
(poster)

"No CSB Discussion Meeting Scheduled"

Organizer: Vinh Nguyen

January 19

Friday 4:00pm
304 Robeson Hall
(poster)

"No CSB Discussion Meeting Scheduled"

Organizer: Vinh Nguyen

January 26

Friday 4:00pm
304 Robeson Hall
(poster)

"No CSB Discussion Meeting Scheduled"

Organizer: Vinh Nguyen

February 2018
February 2

Friday 4:00pm
304 Robeson Hall
(poster)

"No CSB Discussion Meeting Scheduled"

Organizer: Vinh Nguyen

February 9

Friday 4:00pm
304 Robeson Hall
(poster)

Jacob Carroll (Department of Physics, Virginia Tech)

"Sparsely Encoding Convolutional Neural Networks II"

Neural networks are a family of models that range from the biologically inspired recurrent networks that serve as models of the brain, to the feed-forward, deep-learning networks that have been at the forefront of machine learning in recent years. This talk will continue to introduce a specific type of neural network that while biologically inspired, has been developed for the purpose of machine learning and computer science: the sparsely encoding convolutional neural network. This talk will explain how these systems are used for imaged denoising, and how finite size scaling was observed in these networks as they denoised images across many different values of sparsity. This finite size scaling implies that these systems undergo a continuous as sparsity is varied.

Organizer: Vinh Nguyen

February 16

Friday 4:00pm
304 Robeson Hall
(poster)

Priyanka (Department of Physics, Virginia Tech)

"Study of anomalous behavior in one-dimensional harmonic system"

I will start with some theoretical models which have been developed to understand the violation of Fourier's Law in the lower dimension. Anomalous transport, nonlinear temperature profile etc, are the key feature of these model. In detail, I will talk about one of these models (harmonic chain with volume exchange) and present some its analytical and numerical results. I will present exact expression of two-point function in a stationary state and also shows that the dynamics are governed by fractional Laplacian.

Organizer: Vinh Nguyen

February 23

Friday 4:00pm
304 Robeson Hall
(poster)

Weigang Liu (Department of Physics, Virginia Tech)

"A numerical study of the two-dimensional complex Ginzburg-Landau equation"

The complex Ginzburg-Landau equation with additive noise is a stochastic partial differential equation that describes a remarkably wide range of physical systems: coupled non-linear oscillators subject to external noise near a Hopf bifurcation instability; spontaneous structure formation in non-equilibrium systems, e.g., in cyclically competing populations; and driven-dissipative Bose-Einstein condensation, realized in open systems on the interface of quantum optics and many-body physics. We employ a finite-difference method to numerically solve the noisy complex Ginzburg-Landau equation on a two-dimensional domain with the goal to investigate the coarsening dynamics following a quench from a strongly fluctuating defect turbulence phase to a long-range ordered phase. We start from a simplified amplitude equation, solve it numerically, and then study the spatio-temporal behavior characterized by the spontaneous creation and  annihilation of topological defects (spiral waves). We check our simulation results against the known dynamical phase diagram in this non-equilibrium system, tentatively analyze the coarsening kinetics following sudden quenches between different phases, and have begun to characterize the ensuing aging scaling behavior.

Organizer: Vinh Nguyen

March 2018
March 2

Friday 4:00pm
304 Robeson Hall
(poster)

Physics Faculty Meeting (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

March 9

Friday 4:00pm
304 Robeson Hall
(poster)

"Spring Break" (No CSB Discussion Meeting Scheduled)

Organizer: Vinh Nguyen

March 16

Friday 4:00pm
304 Robeson Hall
(poster)

CSB Faculty Meeting (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

March 23

Friday 4:00pm
304 Robeson Hall
(poster)

Ali Charkhesht (Department of Physics, Virginia Tech)

"Probing Collective Motions of Proteins and Hydration Dynamics by a Wide Range Dielectric Spectroscopy"

Studying dynamics of proteins in their biological milieu such as water is interesting because of their strong absorption in the terahertz range that contain information on their global and sub-global collective vibrational modes (conformational dynamics) and global dynamical correlations among solvent water molecules and proteins. In addition, water molecules dynamics within protein solvation layers play a major role in enzyme activity. However, due to the strong absorption of water in the gigahertz-to-terahertz frequencies, it is challenging to study properties of the solvent dynamics as well as conformational changes protein in water. In response, we have developed a highly sensitive megahertz-to-terahertz dielectric spectroscopy system to probe the hydration shells as well as large-scale dynamics of these biomolecules. . Thereby, we have deduced the conformation flexibility of proteins and compare the hydration dynamics around proteins to understand the effects of surface-mediated solvent dynamics, relationships among different measures of interfacial solvent dynamics, and protein-mediated solvent dynamics based on the complex dielectric response from 50 MHz up to 2 THz by using the system we developed. Comparing these assets of various proteins in different classes helps us shed light on the macromolecular dynamics in a biologically relevant water environment.

Organizer: Vinh Nguyen

March 30

Friday 4:00pm
304 Robeson Hall
(poster)

Physics Faculty Meeting (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

April 2018
April 6

Friday 4:00pm
304 Robeson Hall
(poster)

Physics Faculty Meeting (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

April 13

Friday 4:00pm
304 Robeson Hall
(poster)

Riya Nandi (Department of Physics, Virginia Tech)

"Short-Time Dynamics of Three-Dimensional Magnetic Systems with Heisenberg Interaction"

This project aims to explore the initial relaxation dynamics of Heisenberg ferro and anti-ferromagnets. It involves a new simulation technique of combining reversible mode coupling dynamics with the simple diffusive relaxation dynamics in order to obtain the correct dynamic exponent and identify the correct universality class. The system undergoes critical aging and relevant exponents identified. Finally, for a system with non-conserved order-parameter, i.e., the anti-ferromagnet, theory predicts non-universal initial slip exponent. This work aims to study its dependence on the width of the initial distribution of the conserved quantities. This is a work in progress, at best just beginning to show promising results.

Organizer: Vinh Nguyen

April 20

Friday 4:00pm
304 Robeson Hall
(poster)

Physics Faculty Meeting (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

April 27

Friday 4:00pm
304 Robeson Hall
(poster)

Physics Faculty Meeting (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

May 2018
May 4

Friday 4:00pm
304 Robeson Hall
(poster)

Exam Week (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

Center for Soft Matter and Biological Physics Friday Discussion Meetings

Summer 2018

Organizer: Vinh Nguyen

These meetings occur on Fridays from 1:30pm to 2:30pm in Robeson 304 (unless otherwise indicated)

May 2018
May 25

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

June 2018
June 1

Friday 1:30pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

June 8

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

June 15

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

June 22

Friday 1:30pm
304 Robeson Hall
(poster)

Ruslan Mukhamadiarov (Physics, Virginia Tech)

"Transverse Temperature Interface in Katz-Lebowitz-Spohn Model"

Driven lattice gas with attractive nearest neighbor interactions and periodic boundaries demonstrate intriguing dynamics, when parts of lattice held at different temperatures. In two dimensions, this complex system experiences a jamming transition in the high temperature zone, and forms stripes in the low temperature regions. Density profiles are strikingly similar with those for Asymmetric Exclusion Process (ASEP) with open boundary conditions when injection and ejection rates are equal. In this talk, I will discuss the dynamics of two-temperature driven lattice gas system and characterize its density profile using analytical results and Monte Carlo simulations.


Organizer: Vinh Nguyen

June 29

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

July 2018
July 6

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

July 13

Friday 1:30pm
304 Robeson Hall
(poster)

Shadi Esmaeili (Physics, Virginia Tech)

"TBD"


Organizer: Vinh Nguyen

July 20

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

July 27

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

August 2018
August 3

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

August 10

Friday 1:30pm
304 Robeson Hall
(poster)


Organizer: Vinh Nguyen

Center for Soft Matter and Biological Physics Friday Discussion Meetings

Fall 2018

Organizer: Vinh Nguyen

These meetings occur on Fridays from 4:00pm to 5:00pm in Robeson 304 (unless otherwise indicated)

August 2018
August 24

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

August 31

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

September 2018
September 7

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

September 14

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

September 21

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

September 28

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

October 2018
October 5

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

October 12

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

October 19

Friday 4:00pm
304 Robeson Hall
(poster)

"Fall Break" (No CSMB Discussion Meeting)

Organizer: Vinh Nguyen

October 26

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

November 2018
November 2

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

November 9

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

November 16

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

November 23

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

November 30

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

December 2018
December 7

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

December 14

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen

December 21

Friday 4:00pm
304 Robeson Hall
(poster)

Organizer: Vinh Nguyen