Seminars

If not explicitly stated otherwise, seminars take place on Wednesdays, at 16:00 in the lecture room A 945 (Troja, building A, 9th floor).
Indico page for the current semester.

Daniel Scheirich (IPNP MFF)

20.11.2024 at 16:00

Chimera: University HPC Cluster Tutorial

Join us for a practical tutorial on using the Chimera High-Performance Computing (HPC) Cluster. This session is ideal for anyone interested in harnessing HPC resources for research and computational tasks.

Training material:

https://ipnp.cz/?page_id=8244

What to Expect:

Interactive Format: Unlike a traditional seminar, this tutorial offers hands-on experience. Attendees are encouraged to bring their laptops to participate actively.

Topics Covered:

  • Logging in to the cluster
  • Navigating JupyterHub
  • Understanding available partitions
  • Running interactive and batch jobs
  • Efficient use of storage
  • Proper use of different queues
  • Containers and virtual environments
  • Use of the available GPU resources
  • Integrating Visual Studio Code with the cluster (please install Visual Studio Code beforehand if you wish to follow along)

For more details about the Chimera HPC Cluster, please visit:

Who Should Attend:

Researchers, students, and faculty interested in utilizing HPC resources.
Note: Attendance is optional and recommended only for those who are interested.

Zoom:

https://cesnet.zoom.us/j/94528789339?pwd=aTJVdENaZEU5VjdTUzc3SjFZL3Rqdz09

Aren’t anomalies quantum by definition? The case of classical Liouville field theory, prof. Alfredo Iorio, Ph.D. (IPNP FMP CU), Informal Friday Coffee Club seminar, seminar room A 945, Friday November 15th, 13:30

at 16:00
In earlier investigations on classical scale, conformal and Weyl invariances of the Liouville theory, Roman Jackiw evoked the intriguing novel concept of “classical anomaly”. Being the anomaly a disruption of a classical symmetry, induced by quantum field corrections, as discovered by Jackiw himself and Bell and Adler when laying the foundations of the Standard Model of Particle Physics, such concept of classical anomaly is quite novel and interesting.
By computing the Noether charges and their algebra, we show that in Liouville classical theory there is a genuine center of the Virasoro algebra, and that it is related to the trace of the energy-momentum tensor, in curved space. The calculations in the curved spacetime context were far from trivial, and we had to invent novel techniques to circumvent the difficulties encountered by Jackiw and other workers.
Eventually, we proved Jackiw’s conjecture, hence,  with these results in our hands, we are now fully entitled to call this phenomenon a classical gravitational anomaly, as we are able to see that the phenomenon, behind the obstruction to the symmetry noticed by Jackiw, is just the same one that we know from the quantum case: the occurrence of infinite degrees of freedom. Those of a quantum field, in the standard cases, and those of the curved spacetime, in this classical instance of the phenomenon.
A noticeable byproduct here, in the curved context, is that if we trade the Weyl anomaly for the diffeomorphic anomaly, we are able to provide a compact formula for the violation of the diffeomorphic invariance. This formula allows us to find the improvements necessary to remedy Weyl, while losing diffeo invariance.
The importance of conformal field theories is difficult to overestimate, from the early days of string theory, to the present intense days of the AdS/CFT correspondence. Liouville has a prominent role among them, and so it has in a variety of other fields of theoretical investigation. Therefore, on the one hand, it is crucial to learn about the symmetries and anomalies of Liouville field theory already at the classical level. On the other hand, the research presented here opens a debate about phenomena that have been always thought to be due to quantum features of the theory.
Among the latter, first and foremost is the Hawking phenomenon, that in two dimensions is known to be in one-to-one correspondence with the Weyl/trace anomaly. Notice also that, the phenomenon we are disclosing here may even be more general as diffeo anomalies have been seen to be related to Hawking in any dimension.

Martin Sýkora, Jakub Bucko (IPNP MFF)

13.11.2024 at 16:00

Development and production of ATLAS ITk strip modules for HL-LHC (​production news and difficulties including possible tour to the new extended cleanroom in building L)