REMINDER - High Energy Physics Seminars TOMORROW (Borna)

[HECAP - Margherita Di Giovannantonio]

*_HIGH ENERGY PHYSICS SEMINARS_**__*


*Thursday, 11 July* 2024, at *16:00* - *Luigi Stasi Seminar Room **- 
*https://indico.ictp.it/event/10756/
**

**

Borna Salehian (ICTP)


*“Positivity Bounds on Electromagnetic Properties of Media"*

_Abstract_
I will talk about the constraints imposed on the electromagnetic 
response of general media by microcausality (commutators of local fields 
vanish outside the light cone) and positivity of the imaginary parts 
(the medium can only absorb energy from the external field). The effect 
of the medium is encoded in the electric and magnetic permeabilities 
ε(ω, k) and μ(ω, k). In the case of dielectrics, we obtain bounds on the 
low-energy values of the response, ε(0, 0) and μ(0, 0). In particular 
the quantities ε(0, 0) − 1 and ε(0, 0) − 1/μ(0, 0) are constrained to be 
positive and equal to integrals over the imaginary parts of the response.


*To join via Zoom*:

https://zoom.us/j/96455086743

Meeting ID: 964 5508 6743

Passcode: 602968