It is April 28, 2023 and the whole community of the Physics Department of the University of Rome "Tor Vergata", and beyond, gathers in memory of my colleague and illustrious professor Roberto Petronzio.

An institutional event that of the Roberto Petronzio Lecture which over the years it has consolidated with ever greater participation.

The event opened with a small coffee break, which paved the way for the entire afternoon full of personal memories that preceded the Lecture focused on the panorama of theoretical physics.

Ceremony saw a succession of greetings and both personal and institutional interventions, starting from a brief introduction by Prof. Luca Biferale (colleague and friend of Prof. Roberto Petronzio) who gave way for the University of Rome "Tor Vergata" to the Deputy Director of the Physics Department Prof. Lucio Cerrito, followed by the Deputy Pro-Rector Prof. Carlo Nucci in turn followed for the National Institute of Nuclear Physics by the Director Prof. Antonio Zoccoli and the Director of the INFN Rome "Tor Vergata" section Prof. Anna Di Ciaccio,, all moderated by Prof. Giulia M. De Divitiis who closed the ceremonial and introduced the Lecture by Prof. Giorgio Parisi.

The Lecture held by Prof. Giorgio Parisi focused on the key concept of his Nobel Lecture held on 8 December 2021, i.e. on the "multiple equilibrium" in the field of natural sciences, such as physics (but not only). In a short period of time (that of a seminar) Prof. Parisi tried to touch on the various salient ambitions of his Nobel Lecture in order to arouse the audience's curiosity as much as possible and make the same audience participate as well as more aware of the wide applicability of some concepts such as, among other things, the same declaration for the assignment of the Nobel Prize reads "for the discovery of the interaction between disorder and fluctuations in physical systems from an atomic scale to a planetary scale". Both at the beginning and at the end there were memories linked to the friendship that bound Prof. Parisi to Prof. Roberto Petronzio, defined by the same "a magnificent physicist and fantastic friend".

In closing, Prof. Parisi received a gift from Department of Physics of the University of Rome "Tor Vergata" a set of fountain pens as well as many warm applauses from the entire audience. The inevitable requests for the signing of his book and for photos by the participants.

The Physics Department of the University of Rome "Tor Vergata" thanks the organization and gives you an appointment for next year with the next Petronzio Lecture, do not miss it !