This week: 2 QLS seminars (in person) on Tuesday and Wednesday

[Quantitative Life Sciences]

Dear All,

This week, the QLS section is hosting TWO SEMINARS (in person)in the 
Common Area, 2nd floor, ex SISSA Building, via Beirut, 2

You are all most cordially invited to attend!


  * On Tuesday, 5 April 2022 at 15h00 Cesare Nardini (CEA-Saclay,
    France) will give a seminar in presence titled:


*"Phase separation in active matter systems"*

Abstract:
The field of active matter studies materials composed of self-propelled 
entities, which can be either biological or synthetic. Examples of such 
materials stretch across length-scales, from nanorobots to humans, and 
provide a unique plethora of collective behaviors that are inaccessible 
in equilibrium materials, ranging from highly ordered bird flocks to 
phase separation in absence of any attraction among particles. The role 
of theoretical research in active matter is thus not only to explain 
natural phenomena but also to deliver robust models that allow to unveil 
which novel phenomenology we should expect.

The talk will start with a brief overview of active matter and of my 
recent contributions to it. I will then focus on phase separation in 
active systems. This is one of the most fundamental collective phenomena 
arising at high density, and it takes place in systems as diverse as 
bacterial suspensions and biological tissues. I will show that much 
understanding can be drawn by generalising the classical field 
theoretical description of liquid-liquid phase separation (Model B, or 
phi^4 theory) to an active context. After discussing the thermodynamics 
of such model, I will show that activity induces phase separated phases 
that have qualitatively new features with respect to those encountered 
in passive systems. This surprising fact can be rationalised by 
generalising the concept of interfacial tension, crucial in passive 
phase separation, to an active context. Next, we will ask how to control 
these new forms of phase separation in terms of microscopically tunable 
parameters; although this question is still largely open, I will 
describe the recent progresses we made by studying minimal models of 
active particles.

Indico page https://indico.ictp.it/event/9914/

*************************************************************************************************************************

  * On Wednesday, 6 April 2022 at 15h00 Iuri Macocco (SISSA) will give a
    seminar in presence titled:

*"**An intrinsic dimension estimator for discrete-metric spaces: 
formalization and first applications**”*

Abstract:
Real world datasets characterised by discrete features are ubiquitous: 
 From categorical surveys to clinical questionnaires, from unweighted 
networks to genomic strands. Nonetheless, the development of methods to 
treat data with discrete features lags behind, particularly concerning 
geometric and manifold learning approaches. Due to the lack of such 
tools, the analysis of aforementioned dataset still relies on algorithms 
developed for continuous spaces, inevitably introducing approximations, 
error and biases. In this work, starting from the appropriate definition 
of volumes on lattices, we develop a very simple, yet effective, routine 
to estimate the intrinsic dimension of datasets naturally described by 
discrete metric spaces. Besides, our id estimator allows to explicitly 
select the scale at which the id is computed, an important property that 
is hardly provided even in estimators for continuous spaces. We assess 
the validity of the new estimator on artificial datasets against a state 
of the art continuous estimator and then apply it to a controlled-id 
spin system as well as to an ensemble of genomic sequences

Indico page https://indico.ictp.it/event/9921/




Best regards,

Erica

Erica Sarnataro
Group Secretary
Quantitative Life Sciences
The Abdus Salam International Centre for Theoretical Physics (ICTP)
Trieste,  Italy
Tel. +39-040-2240623
www.ictp.it/research/qls.aspx
e-mail:qls at ictp.it