# Web Content Display

## Aktualności

# Blogs

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday, January 24 at 12:15, which will be given by

Piotr Kotko (AGH)

entitled

“Gluon scattering amplitudes within a new Wilson line-based action for gluodynamics”

I discuss a reformulation of the Yang-Mills action, that allows for an efficient calculation of gluon tree amplitudes. The new action is obtained via canonical field transformations that are based on Wilson line type functionals. I also discuss prospects and initial results for loop amplitudes.

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

December 13 at 12:15, which will be given by

Yizhuang Liu (IFT UJ)

entitled

“Asymptotic KNO scaling for Mueller's dipole in the double-logarithm limit”

We analyze Mueller's QCD dipole wave function evolution in the double logarithm (DLA) limit. Using complex analytic methods, we show that the distribution of dipoles in the wave function asymptotically satisfies the Koba-Nielsen-Olesen (KNO) scaling with a novel scaling function f(z). The behavior of the scaling function in the DLA limit is qualitatively different from the expected scaling e^{-z} in the diffusion limit: at large z the f(z) decays as ze^{-z/0.3917} , while at small z the speed of growth is log-normal-like . The bulk and asymptotic results are shown to be in good agreement with the measured hadronic multiplicities in DIS, as reported by the H1 collaboration at HERA.

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

December 6 at 12:15, which will be given by

Zdzisław Burda (AGH)

entitled

“Cleaning large-dimensional covariance matrices for correlated samples".

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

November 29 at 12:15, which will be given by

Alberto Ramos (University of Valencia)

entitled

“Many uses of automatic differentiation".

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

November 22 at 15:15, which will be given by

Farid Salazar (Institute for Theoretical Physics, UCLA)

entitled

“Sudakov suppression and gluon saturation at NLO".

The seminar will be ONLY in a remote mode.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

November 15 at 12:15, which will be given by

Michał Praszałowicz (IFT UJ)

entitled

“Konferencja Excited QCD 2022".

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

November 8 at 12:15, which will be given by

Pavel Buividovich (University of Liverpool)

entitled

“Quantum chaos in supersymmetric quantum mechanics".

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday, October 25 at 12:15, which will be given by

Giorgio Torrieri (Campinas University)

entitled

“The hidden gauge symmetry of relativistic dissipative hydrodynamics “

Abstract: The observation, in hadronic collisions, of "ideal fluid" type behavior in systems of a comparatively small number of particles, presents a conceptual puzzle, since the way we usually derive hydrodynamics is via approximating "many" particles as a continuum. I will argue that making sense of this requires re-deriving relativistic hydrodynamics as a "bottom-up" theory, with no reference to microscopic physics except the local emergence of a thermalized system. We attempt to do this using basic statistical mechanics, and find the appearance of a gauge-like redundancy hidden within relativistic dissipative hydrodynamics, arising from the fluctuation-dissipation theorem. This might lead to the apparently counter-intuitive conclusion that in the small viscosity limit it might indeed be that smaller systems could thermalize faster.

The seminar will be on-site in the seminar room D-2-02.

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on MONDAY,

October 17 at 12:15, which will be given by

David Albandea (University of Valencia)

entitled

“Learning trivializing maps“

Abstract: The recent introduction of machine learning techniques, especially normalizing flows, for the sampling of lattice gauge theories has shed some hope on improving the sampling efficiency of the traditional HMC algorithm. However, naive usage of normalizing flows has been shown to lead to bad scaling with the volume. In this talk I will introduce normalizing flows commenting on its computational cost scaling towards the continuum. I will then propose using local normalizing flows at a scale given by the correlation length: even if naively these transformations have a very small acceptance, when combined with HMC lead to algorithms with high acceptance and reduced autocorrelation times compared with HMC.

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

October 11 at 12:15, which will be given by

Leszek Motyka and Tomasz Stebel (IFT)

entitled

"Diffraction / Low x 2022".

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

October 4 at 12:15, which will be given by

Kayman Jhosef Carvalho Gonçalves (Campinas University)

entitled

“Spin alignment of vector mesons as a probe of spin hydrodynamics and freeze-out“

Abstract: We argue that a detailed analysis of the spin alignment of vector mesons can serve as a probe of some aspects of spin dynamics in the vortical fluid for which there have been quite a few theoretical developments but relatively little phenomenology: The degree of relaxation between vorticity and parton spin polarization, and the degree of coherence of the hadron wavefunction at freeze-out. We show, using a coalescence model, that local spin density and vorticity impact the hadron wavefunction in different ways, and this is much more straightforward to disentangle for a vector meson than for a spin 1/2 baryon. We comment on the relevance of this issue for the current lack of consistency between experimental data on Lambda polarization and K*, phi spin alignment. Based on https://arxiv.org/abs/2104.12941

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

June 14 at 12:15, which will be given by

Karol Życzkowski (IFT)

entitled

“Thirty-six quantum officers of Euler: quantum solution of a classically impossible problem”

Abstract: Negative solution to the famous problem of 36 officers of Euler implies that there are no two orthogonal Latin squares of order six. We show that the problem has a solution, provided the ranks and the units of each officer can be entangled, and construct quantum orthogonal Latin squares of this size. The solution can be visualized on a chessboard of size six, which shows that 36 officers are split in nine groups, each containing of four entangled states. This design provides a unique example of extremal quantum state and allows us to construct an original quantum error detection code.

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

We would like to invite you to the lecture on The physics of the QCD energy-momentum tensor

The lecture will be on Monday, 6th June at 2pm:

https://events.ncbj.gov.pl/event/137

Speaker: Cédric Lorcé (CPHT, École Polytechnique, Palaiseau, France)

Title: The physics of the QCD energy-momentum tensor (2/2)

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

June 7 at 12:15, which will be given by

prof. Gert Aarts (Swansea University)

entitled

“Machine learning for lattice field theory and back”

Abstract: Recently, machine learning has become a popular tool to use in fundamental science, including lattice field theory. Here I will report on recent progress, starting with (by now) basic applications (phase transitions and critical exponents), moving on to new ideas for the Inverse Renormalisation Group and ending with more speculative suggestions on quantum-field theoretical machine learning.

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Dear All,

We would like to invite you to the lecture on The physics of the QCD energy-momentum tensor

The lecture will be on Monday, 30th May at 2pm:

https://events.ncbj.gov.pl/event/137/

Speaker: Cédric Lorcé (CPHT, École Polytechnique, Palaiseau, France)

Title: The physics of the QCD energy-momentum tensor (1/2)

Please join the meeting from your computer, tablet or smartphone.

https://www.gotomeet.me/NCBJmeetings/electron-ion-collider

Best Regards,

Krzysztof Kutak, Jakub Wagner, Agnieszka Łuszczak (on behalf of the representatives, https://eicpl.ifj.edu.pl)

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

May 31 at **15:15**, which will be given by

Joao Barata (Brookhaven National Laboratory)

entitled

“Jet quenching in a digital quantum computer”

Abstract: The fast development of quantum technologies over the last decades has offered a glimpse to a future where the quantum properties of multi-particle systems might be more fully understood. So far, quantum computing has seen ample application in areas such as quantum chemistry or condensed matter, but its usage in high-energy physics is still in its infancy. In the particular case of QCD jets, these technologies might offer a way to more fully understand the intricate interference pattern arising from the multi-parton cascade. In this talk, I will discuss an approach to study the evolution of jets in the presence of a background field. I will consider single parton evolution, neglecting radiative energy loss and focusing on momentum diffusion. Using the typical approximations found in jet quenching literature, this problem is easily solved and thus it offers a good first step towards studying full jets. Besides the formulation of the problem in terms of operations on the quantum computer, I will also show some early numerical results using qiskit.

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on Tuesday,

May 24 at 12:15, which will be given by

Sebastian Sapeta (IFJ PAN)

entitled

“Triple-collinear one-loop splitting functions in QCD”

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz

Dear All,

We would like to invite you to the lecture on Diffraction in hadronic collisions

The lecture will be on Monday, 16th May at 2pm:

https://events.ncbj.gov.pl/event/137/

Speaker: Anna Staśto (Penn State University, USA)

Title: Diffraction in hadronic collisions (1/2)

Dear All,

we have the pleasure to invite you to the Particle Theory Seminar on WEDNESDAY,

May 18 at 12:15, which will be given by

Prof. Michał Spaliński (NCBJ)

entitled

“Hydrodynamic Attractors and Quark-Gluon Plasma”

Abstract: The successful application of fluid-dynamical models to the physics of Quark-Gluon Plasma created in ultra-relativistic nuclear collisions has inspired a number of theoretical investigations aimed at understanding how this is possible, given the complexity of the post-collision state. I will describe a possible resolution of this "early-thermalisation puzzle" which is suggested by studies of various idealised models.

The seminar will be in a hybrid mode, local people are invited to meet in the seminar room D-2-02.

Piotr Korcyl, Jacek Wosiek, Michał Praszałowicz