سخنران: مریم سلیمانی نیا، پژوهشگاه دانش های بنیدی

16 تیر 1399
11:00 تا 12:00

https://www.skyroom.online/ch/ipm-particles/journal-club-ep

سخنران: حمیدرضا صفری، پژوهشگاه دانش های بنیادی

12 تیر 1399
11:00 تا 12:00

https://www.skyroom.online/ch/ipm-particles/theory-weekly-seminar

سخنران: س. آقاپور، پژوهشکده فیزیک

12 تیر 1399
15:00 تا 17:00

سمینار مجازی
Helicity and spin as conserved quantities have been considered vastly in recent years, especially in the fields of optics and fluid dynamics. In contrast to what is usually thought, helicity and spin of the electromagnetic fields are definable and useful at the classical level as well as the quantum level. The classical quantities have the expected relation with their quantum counterparts. Besides, it has been clarified to a certain extent that the separation of the total angular momentum of light into orbital and intrinsic (spin) parts leads to meaningful and consistent definitions of these independently conserved quantities. The importance of this fact In applied optics is that it has opened the possibility of preparing laser beams in eigenstates of orbital angular momentum in order to carry huge amounts of information for communication purposes. On the other hand, helicity is considered to be tightly related with the chirality of electromagnetic waves and has been successfully used to explain the interaction of light with chiral molecules. These results have also inspired similar investigations in fluid dynamics for spinning acoustic waves. From the theoretical point of view, the symmetries of the action (and the equations of motion) underlying the conservation of helicity and spin according to the Noether theorem and the major role of the duality symmetry have been studied. The inter-relation of helicity and spin at classical level as well as their non-local nature have also been investigated. In this talk, I will try to touch on different aspects and current status of this research and review some of the most important, old and new discussions under this topic as much as I can and at the end say a few words about this subject in the context of gravity.

سخنران: Nima Afkhami-Jeddi, University of Chicago

12 تیر 1399
08:30 تا 09:30

We study the torus partition functions of free compatic bosonic CFTs in two dimensions. Integrating over Narain moduli defines an ensemble-averaged free CFT. We calculate the averaged partition function and show that it can be reinterpreted as a sum over topologies in three dimensions. This result leads us to conjecture that an averaged free CFT in two dimensions is holographically dual to an exotic theory of three-dimensional gravity.

سخنران: مریم قهرمانی، پژوهشگاه دانش های بنیدی

11 تیر 1399
11:00 تا 12:00

Meeting's link: https://www.skyroom.online/ch/ipm-particles/school-of-particles-and-accelerators-weekly-meeting

Indico: https://indico.particles.ipm.ir/indico/event/362/?view=standard