17 MAY 2022
09:00 - 16:30

The meeting provides a unique forum for experienced as well as potential users of synchrotron light source in Iran to discuss the scientific, technical, and practical issues about the use of synchrotron radiation in basic science, engineering, and medicine.



Link: http://ilsf.ipm.ac.ir/users-meeting1401/

17 MAY 2022
11:30 - 13:00

Event Link :
https://join.skype.com/Neq7oL9ixMQy


Link: http://scs.ipm.ac.ir/new/docs/ashmore.jpeg

17 MAY 2022
14:00 - 15:00

Date and time
Tuesday, 17th of May, 2022 (27th of Ordibehesht, 1401), 2:00 pm (Tehran zone)

Link
https://us02web.zoom.us/j/83538126663?pwd=VTNQWVpOdDZ1ajAvbVI1WklKODZGUT09


Meeting ID: 835 3812 6663
Passcode: 785277

Abstract
In this letter, I investigate the deformation of the ModMax theory, as a unique Lagrangian of non-linear electrodynamics preserving both conformal and electromagnetic-duality invariance, under $T-T^{\bar}$-like
flows. I show that the deformed theory is the generalized non-linear Born-Infeld electrodynamics. Being inspired by the invariance under the flow equation for Born-Infeld theories, I propose another $T-T^{\bar}$-like operator generating the ModMax and generalized Born-Infeld non-linear electrodynamic theories from the usual Maxwell and Born-Infeld theories, respectively.





Link: https://us02web.zoom.us/j/83538126663?pwd=VTNQWVpOdDZ1ajAvbVI1WklKODZGUT09

17 MAY 2022
15:30 - 16:30

17 MAY 2022
17:00 - 18:00

The entropy of a de Sitter horizon was derived long ago by Gibbons and Hawking via a gravitational partition function. Since there is no boundary at which to define the temperature or energy of the ensemble, the statistical foundation of their approach has remained obscure. To place the statistical ensemble on a firm footing we introduce an artificial "York boundary", with either canonical or microcanonical boundary conditions, as has been done previously for black hole ensembles. The partition function and the density of states are expressed as integrals over paths in the constrained, spherically reduced phase space of pure 3+1 dimensional gravity with a positive cosmological constant. The canonical ensemble includes a patch of spacetime without horizon, as well as configurations containing a black hole or a cosmological horizon. In this talk I briefly discuss issues related to the domain and contour of integration in the path integral, and justify the adopted choices for those as far as possible. I also explain thermodynamic phases and (in) stability, and discuss an evolving reservoir model that can stabilize the cosmological horizon in the canonical ensemble. Finally, I explain how the Gibbons-Hawking partition function on the 4-sphere can be derived as a limit of well-defined thermodynamic ensembles.
Based on arXiv: 2204.05324.

(for participating in this event, please contact us: "particles@ipm.ir")

18 MAY 2022
09:00 - 16:30

The meeting provides a unique forum for experienced as well as potential users of synchrotron light source in Iran to discuss the scientific, technical, and practical issues about the use of synchrotron radiation in basic science, engineering, and medicine.



Link: http://ilsf.ipm.ac.ir/users-meeting1401/

18 MAY 2022
11:00 - 12:00

We consider the symmetry-resolved R\'{e}nyi and entanglement entropies for two-dimensional conformal field theories on a circle at nonzero temperature. We assume a unique ground state with a nonzero mass gap induced by the system's finite size and then calculate the leading corrections to the contributions of individual charge sectors in a low-temperature expansion. Besides the size of the mass gap and the degeneracy of the first excited state, these universal corrections depend only on the four-point correlation function of the primary fields. We also obtain thermal corrections to the full counting statistics of the ground state and find that the fluctuations of probabilities scale as $e^{-2 \pi \Delta_{\psi} \beta /L}$, where $\Delta_{\psi}$ is the scaling dimension of the lowest weight states. As an example, we explicitly evaluate the thermal corrections to the symmetry-resolved entanglement entropy and FCS for the spinless fermions.


Meeting Link

https://meet.google.com/zmx-jjzc-gye
https://indico.hep.ipm.ir/e/mghasemi

Link: https://meet.google.com/zmx-jjzc-gye

18 MAY 2022
16:30 - 18:30

James Freitag and I recently introduced what we call the �degree of nonminimality�. It measures, in some sense that I will make precise, how many parameters are needed to witness that a given finite rank type is not of rank 1. I will explain how the truth of the Borovik-Cherlin conjecture for algebraic homogeneous spaces, applied to binding group actions in certain totally transcendental theories of interest (namely DCF and CCM), leads to a useful bound on the degree of nonminimality. This is motivated by the search for new methods to verify the strong minimality of an algebraic differential equation.

Zoom info:
https://us06web.zoom.us/j/86380285511?pwd=Z2puU2w0NzIwL3doM1ljcCtBdHFFdz09
Meeting ID: 863 8028 5511
Passcode: 362880

18 MAY 2022
14:00 - 15:00

Natural hyperbolic two-dimensional systems are a fascinating class of materials that could open alternative pathways to manipulating plasmon propagation and light-matter interactions. Here, we present a comprehensive study of the optical response in Td -WTe2 by means of density-functional and many-body perturbation theories. We show how monolayer WTe2 with in-plane anisotropy sustains hyperbolic plasmon polaritons, which can be tuned via chemical doping and strain. The latter is able to extend the hyperbolic regime toward the near-infrared with low losses. Moreover, WTe2 can even be switched between elliptic and hyperbolic regimes with a moderate strain. In addition, plasmons in WTe2 are characterized by low losses owing to electron-phonon scattering, which is responsible for the temperature dependence of the plasmon line width. Interestingly, the temperature can also be utilized to tune the in-plane anisotropy of the WTe2 optical response.


To join the webinar, please follow this link and log in as a guest



https://www.skyroom.online/ch/schoolofnanoscience/weeklyseminars

19 MAY 2022
11:00 - 12:30

https://www.skyroom.online/ch/arashfj/weekly-seminar-ipm-bio

Link: https://www.skyroom.online/ch/arashfj/weekly-seminar-ipm-bio

25 MAY 2022
18:00 - 19:00

There are many ways to study life, and one that is particularly appealing to physicists is regarding it as self-organized active soft matter that is away from equilibrium ``just the right way’’. In this Colloquium, I will discuss this notion, and provide a number of examples of how we can begin to put together simple systems - from basic ingredients that we fully understand - that would exhibit the kind of active behaviour we find in living systems. In particular, I will discuss the general class of chemical activity both as the source of non-equilibrium drive and the underlying mechanism for self-organization. Cells and microorganisms produce and consume all sorts of chemicals, from nutrients to signalling molecules. The same happens at the nanoscale inside cells themselves, where enzymes catalyze the production and consumption of the chemicals needed for life. In this colloquium, I will discuss a generic mechanism by which such chemically-active particles, be it cells or enzymes or engineered synthetic colloids, can "sense" each other and ultimately self-organize in a multitude of ways. A peculiarity of these chemical-mediated interactions is that they break action-reaction symmetry: for example, one particle may be repelled from a second particle, which is in turn attracted to the first one, so that it ends up "chasing" it. Such chasing interactions allow for the formation of large clusters of particles that "swim" autonomously. Regarding enzymes, we find that they can spontaneously aggregate into clusters with precisely the right composition, so that the product of one enzyme is passed on, without lack or excess, to the next enzyme in the metabolic cascade. Finally, I will discuss how breaking the action-reaction symmetry can allow a system described by two scalar fields to exhibit spontaneous breaking of time translation, time-reversal, space translation, and polar symmetries.

Link: https://www.skyroom.online/ch/schoolofphysics/colloquium