Emilie Oakes is joining our group over the summer as part of the SBI REU program!

There is at least one and possibly two postdoctoral positions available in the Manning group beginning in Fall 2015 or Winter 2016.  Please email Lisa or see advertisement on the Welcome page for more info.

Giuseppe Passucci passed his oral research exam, setting the stage for him completing his Ph. D. in physics.  Congratulations, Giuseppe!

The Syracuse University Board of Trustees has approved the Provost’s decision that Lisa Manning be granted tenure and promoted to the rank of Associate Professor.

Manning’s proposed work, “Using Single-Cell Mechanical Properties to Predict Pattern Formation and Mechanical Response in Biological Tissues” will be funded over three years. Cottrell Scholar Awards (15 awarded annually in the sciences throughout the country) recognize early career faculty with exceptional potential in both research and academic leadership:

http://rescorp.org/news/2015/02/rcsa-directors-approve-48-research-awards
http://rescorp.org/cottrell-scholars

Our paper on extracting force chains in granular materials using methods from network theory has just been published as an advance article in Soft Matter.  An image from our work will also appear on the front cover!

Danielle S. Bassett, Eli T. Owens, Mason A. Porter, M. Lisa Manning, Karen E. Daniels. “Practical Methods for the Examination of Force Chain Network Architecture in Granular Materials”  Soft Matter, 2015, DOI: 10.1039/C4SM01821D (2015)

Preprint: arXiv:1408.3841

Link to manuscript: M. L. Manning and A. J. Liu, “A random matrix definition of the boson peak,” accepted to Europhysics Letters, arXiv:1307.5904 (2015)

An old theory by Debye predicts that the number of sound modes in a crystal increases as the frequency of the sound mode to the power (d-1), where d is the number of dimensions. It has long been recognized that the boson peak—defined as an excess of sound modes compared to the Debye expectation—is a universal phenomenon in disordered solids.  However, even perfectly crystalline solids show an excess of modes compared to Debye at sufficiently high frequencies.   Therefore, we suggest a new definition of the boson peak, in terms of its eigenvector statistics.  This definition has two important advantages over the old one: it does not rely on a comparison to Debye scaling and it is true only for disordered solids. In addition, this manuscript identifies a new universality class in random matrices based on their eigenvector statistics, and indicates that modes of the boson peak have the same eigenvector statistics as this new universality class.  This result implies that any random matrix with disorder and a generalized global translation invariance should exhibit this universality, explaining the ubiquity of boson peaks in disordered solids. Finally, this paper identifies a class of “diagonally dominant” random matrices that capture the scaling of the frequency location of the boson peak in jammed solids.

Giuseppe Passucci is giving an invited soundbite at the NY Complex Matter workshop.

Max Dapeng Bi will be giving an invited talk at the APS March Meeting in San Antonio in a symposium entitled “Mechanical interactions and pattern formation in multicellular systems” on 3/6/15 starting at 11:15am.

Lisa Manning will be giving an invited talk at the APS March Meeting in “Frontiers of Soft Matter I” symposium, at 11:15am on 3/2/15.  She is also giving an invited talk at the Soft Matter Gordon conference Aug 9-14, 2015.

The Syracuse Soft Matter Program presents
a public Lecture  "The sound of disorder"
featuring: Lisa Manning, Assistant Professor at Syracuse University
Wednesday, October 29, 2014
7:00 p.m.  Watson Theater

Abstract:  You are familiar with liquid-to-solid transitions — if you cool down water, it will turn into ice.   This large-scale observation is related to the microscopic order; in a liquid all the molecules are jumbled up, while in a solid they often line up in nice neat rows. However, scientists have recently become interested in a different type of liquid-to-solid transition where the constituent parts remain all jumbled up – or disordered – even in the solid.  You are familiar with this, too:  you can walk along a sandy beach, which means the sand is supporting your weight like a solid, but when you pick up the sand it will flow through your fingers like a liquid.  This “jamming” transition shows up everywhere: stiffening of homemade mayonnaise, You Tube videos of people running across tubs of cornstarch and water, manufacturing of plastics and golf clubs, robotics, and even developmental biology.  In my talk I will explain how all these things are related, and describe a bit of the recent research in our group to understand the theoretical underpinnings of these materials. In particular, I will explain how sound modes (or vibrations) in these solids help us explain their behavior.

Open to all ages and backgrounds.  Come with your curiosity and questions!

Reception to follow.

Professor Lisa Manning has received recognition for both research and teaching, including an Alfred P. Sloan Fellowship, an NSF CAREER grant, an NSF Graduate K-12 Fellowship, and two departmental teaching awards. She lives in Syracuse with her husband and one-year-old daughter.

We just posted a very exciting new paper on the arXiv:1409.0593! This work, pioneered by first author Max Dapeng Bi, shows that the vertex model, which has been widely and successfully used to describe cell shapes and statistics in biological tissues, has an unexpected rigidity transition.  This transition, instead of being controlled by the cell density (as it is in jamming for particulate systems) is controlled by the cell shape.  Specifically, it is controlled by the cell's perimeter-to-area ratio (measured from a cross-sectional cut through a monolayer). Interestingly, this model also predicts that in confluent tissue (where there are no gaps between cells) adhesion can help make the tissue more fluid-like, which is the opposite of what happens in particulate matter.  We are currently collaborating with several biology groups to test aspects of this exciting prediction.