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Inclusive processes at high energies are studied in a non-perturbative
approach in QCD using a modified Quark-Gluon String Model. Theoretical and
experimental aspects of diffraction dissociation are especially discussed.
In the calculations of cross sections, the parameters of complex nonlinear
trajectories of Pomeranchuk and Reggeons are used. Particular attention
is paid to elastic and inelastic processes at LHC energies.

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Gravitational formfactors describe the (angular) momentum distribution in hadrons as well as their coupling to gravity. The equivalence principle may be extended to be valid separately for quarks and gluons. The small violation of such an extension may be related to the analog of shear viscosity contribution and be a counterpart of its smallness.

Collective effects are reviewed for collisions of various systems – from proton-proton to heavy ion – in wide energy range. Collectivity is one of the crucially important and most essential fea-tures in reactions with subatomic particles due to strong interaction. As consequence, a study of collective behavior in multiparticle production processes provides one of the most sensitive and promising probes for detailed investigation of basis features of strong interaction. Recent exper-imental results obtained at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) are considered. Hadron jets being one of the most famous collective effects in strong interaction are intensively study in various collisions [1]. In proton-proton interactions such studies devote to the better understanding of hadronization, precise determination of strong coupling constant, parameters of top quark and its production [2], verification of the predictions of Quantum Chromodynamics (QCD) in events with different topology, search for the physics beyond of Standard Model (SM), in particular, within Effective Field Theory (EFT) approach [3, 4] for top quark sector [2, 5–8]. Investigations of different nuclear collisions focus on exploration of the phase diagram of strongly interacting matter, particularly, on detailed study of properties of quark-gluon matter under extreme conditions considered presently as the strongly coupled quark-gluon plasma (sQGP). Results at RHIC [9] and LHC [10–12] energies provide important information about event shapes as well as transport and thermodynamics properties of the hot medium for various flavors. Measurements show clearly the collective behavior of heavy quarks in nucleus-nucleus interactions. Studies of jets in strongly interacting environment via correlations of different particles including heavy hadrons lead to new constraints for energy loss models, allow the search of the new physics signatures with heavy-ion collisions. First results have been obtained at the LHC for massive gauge bosons and antitop-top pair production in proton-nuclear and heavy ion collisions at multi-TeV energies. The surprising sQGP-like collectivity has been observed in collision systems smaller than even moderate nuclei, especially, at the LHC energies. Experimental results obtained for discrete symmetries of QCD at finite temperatures confirm indirectly the topologically non-trivial structure of QCD vacuum [13–17]. Such investigations are important for the decision of the problems of CP invariance of the strong interaction and baryon asymmetry of Universe. In the soft sector of the strong interaction one can expect some novel mechanisms for multiparticle production due to collectivity in very high energy nuclear collisions, in particular, increasing of coherent particle production. The investigation of Bose–Einstein condensation (BEC) will shed new light on the nature of superfluidity of strongly interacting matter which is the one of the fundamental properties of sQGP, on the possibility of laser-like regime for pion production at very high energies [18]. Studies of collective effects in strong interaction processes provide new important results for relativistic astrophysics, cosmology and cosmic ray physics. The recent measurements of femtoscopic correlations allow, in particular, the indirect estimations for parameters of hyperon–nucleon potentials. The new constrains for these potentials will make model predictions more reliably for compact astrophysical objects [19–23]. Studying the possible BEC effect on the pion yield at very high energies [24] can be considered one of perspective research directions for better understanding of the nature of the muon puzzle in ultra-high energy cosmic ray (UHECR) measurements [25–27]. Therefore collective effects in strong interaction processes studied on accelerator facilities are important for various fields of fundamental physics and investigation of the effects has large interdisciplinary value.

References
[1] V. A. Okorokov, Int. J. Mod. Phys. A 27, 1250037 (2012).
[2] U. Husemann, Prog. Part. Nucl. Phys. 95, 48 (2017).
[3] S. Willenbrock and C. Zhang, Annu. Rev. Nucl. Part. Sci. 64, 83 (2014).
[4] E. E. Boos, Phys. Usp. 65, 653 (2022).
[5] C. Zhang and S. Willenbrock, Phys. Rev. D 83, 034006 (2011).
[6] I. Brivio et al., JHEP 2002, 131 (2020).
[7] S. Bißmann et al., JHEP 2106, 010 (2021).
[8] V. A. Okorokov, J. Phys.: Conf. Ser. 1690, 012006 (2020); Phys. At. Nucl. 86, 742 (2023).
[9] V. A. Okorokov, Phys. At. Nucl. 72, 147 (2009); Proc. of the HEPFT2014. Eds. V. Petrov and R. Ryutin. World Scientific, Singapore (2015), p. 189; Eur. Phys. J. Web of Conf. 158, 01004 (2017).
[10] ALICE Collaboration, arXiv: 2211.04384 [nucl-ex].
[11] G. Aad et al. (ATLAS Collaboration), arXiv: 2404.06829 [hep-ex].
[12] A. Hayrapetyan et al. (CMS Collaboration), arXiv: 2405.10785 [hep-ex].
[13] D. E. Kharzeev, Annals Phys. 325, 205 (2010).
[14] V. A. Okorokov, Phys. At. Nucl. 80, 1133 (2017).
[15] J. Zhao and F. Wang, Prog. Part. Nucl. Phys. 107, 200 (2019).
[16] W. Li and G. Wang, Annu. Rev. Nucl. Part. Sci. 70, 293 (2020).
[17] D. E. Kharzeev and J. Liao, Nature Rev. Phys. 3, 55 (2021).
[18] V. A. Okorokov, Adv. High Energy Phys. 2016, 5972709 (2016); Phys. At. Nucl. 82, 838 (2019).
[19] M. Oertel et al., Rev. Mod. Phys. 89, 015007 (2017).
[20] G. Baym et al., Rep. Prog. Phys. 81, 056902 (2018).
[21] L. Baiotti, Prog. Part. Nucl. Phys. 109, 103714 (2019).
[22] F. J. Llanes-Estrada and E. Lope-Oter, Prog. Part. Nucl. Phys. 109, 103715 (2019).
[23] J. M. Lattimer, Annu. Rev. Nucl. Part. Sci. 71, 433 (2021).
[24] V. A. Okorokov, Phys. At. Nucl. 87, 172 (2024).
[25] S. Mollerach and E. Roulet, Prog. Part. Nucl. Phys. 98, 85 (2018).
[26] L. A. Anchordoqui, Phys. Rep. 801, 1 (2019).
[27] M. Kachelrieẞ and D. V. Semikoz, Prog. Part. Nucl. Phys. 109, 103710 (2019).

Discussion leader Roman Zhokhov (IZMIRAN, Troitsk)

The transition of strong-interaction matter from the hadronic phase to the quark-gluon plasma phase is a rapid crossover rather than a true phase transition in nature. A true phase transition in strong-interaction matter is expected to exist only under certain conditions, such as the chiral limit of massless quarks.
In this talk, I will present our recent studies on the true phase transition of strong-interaction matter in the chiral limit of massless quarks, along with its microscopic origin. Our research is based on (2+1)-flavor lattice QCD simulations using highly improved staggered fermions, with pion masses ranging from 160 MeV down to 55 MeV. Additionally, I will discuss baryon electric charge correlation, which can serve as a magnetometer of QCD.

In this report the influence of relativistic rotation on QCD
properties will be considered. I am going to review the results that
were obtained within lattice simulation of QCD. It has become
commonplace to perform such studies in the reference frame rotating
with the system under investigation. In this case there appears the
gravitational field and the problem is reduced to study of QCD in this
external gravitational field. Within the report the following topics
will be reviewed. The influence of relativistic rotation on the QCD
critical temperatures. Equation of state of rotating QCD and the
moment of inertia of quark-gluon plasma. Inhomogeneous phase
transitions in rotating quark-gluon plasma.

After a historical introduction I will review progress in description of the pion degrees of freedom in equilibrium and nonequilibrium nuclear matter. Effects of the softening of the pion mode and pion condensation will be considered. Applications to such nuclear systems as atomic nuclei, neutron stars, heavy-ion collisions, and hypothetical nuclear systems will be discussed.

References

D.N. Voskresensky,``Pion Softening and Pion Condensation,''
Phys. Atom. Nucl. 83 (2020) no.2, 188-202

D.N. Voskresensky, ``Many particle effects in nucleus nucleus collisions,''
Nucl. Phys. A 555 (1993), 293-328

D.N. Voskresensky,``S-wave pion condensation in symmetric nuclear matter,''
Phys. Rev. D 105 (2022) no.11, 116007

D.N. Voskresensky, ``Pion-sigma meson vortices in rotating systems,''
Phys. Rev. D 109 (2024) no.3, 034030

D.N. Voskresensky, `` Pion degrees of freedom in nuclear matter, from 1971 till tomorrow".

I will compare the main confinement mechanisms in QCD, confinement by magnetic monopoles and by quantised magnetic flux tubes, vortices. Then, I will concentrate on problems with the detection of vortices. A further interesting question concerns the relation to the spontaneous breaking of chiral symmetry.

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The most valuable task for high-energy physics at future colliders is the study of the Standard Model features in detail. That is required to resolve crucial problems of this model including the origin of the spontaneous symmetry breaking, the metastability of the Higgs boson vacuum, the symmetry and mass hierarchy of three fermion generations, etc. High statistics and advanced experimental accuracy at future Z factories can provide a substantially new level of the SM verification [1]. The physical program of such factories extends the studies performed at LEP because of higher statistics, modern detectors and advanced analysis techniques. All that challenges theory to provide adequately accurate SM predictions. Those challenges and some recent developments are discussed. ReneSANCe [1] Monte Carlo event generator and MCSANC [3] integrator presented. They are developed for high-precision studies of electroweak physics at future electron-positron colliders.

[1] A. Blondel, J. Gluza, S. Jadach et al., CERN Yellow Reports: Monographs 3/2019; arXiv:1809.01830 [hep-ph].
[2] R. Sadykov, V. Yermolchyk, Comput. Phys. Commun. 256 (2020), 107445.
[3] S.G. Bondarenko, A.A. Sapronov, Comput. Phys. Commun. 184 (2013), 2343-2350.

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Discussion leaders
Oleg Teryaev (JINR, Dubna) &
Vitaly Bornyakov (Logunov IHEP, NRC KI, Protvino)

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Odderon is the C-odd amplitude which does not die out (or die very slowly) with energy. We consider the constrains on the Odderon properties and the
perturbative QCD odderon given at the lowest $\alpha_s$ order by the three gluon exchange. Then we discuss the experimental indications for the odderon
contribution to high energy proton-proton elastic scattering and some other processes in which the odderon may reveal itself.

References

ATLAS Collaboration, G. Aad et al., Eur. Phys. J. C 83, 441 (2023).

Odderon contribution in light of the LHC low-tt data ,
E.G.S. Luna, M.G. Ryskin, V.A. Khoze, e-Print:2405.09385 [hep-ph]

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The soft and hard QCD processes are analyzed by ALICE, ATLAS and CMS experiments using samples of proton-proton and AA collisions collected by the LHC at different energies. Measurements of jet production rates, jet properties, particle multiplicity, particle momentum spectra and correlations are presented.
The results are compared to predictions of theoretical models at leading- and next-to-leading orders of QCD. The data in combination with HERA and CMS and
ATLAS results are used to measure the strong coupling constant and for PDF constraints.

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Discussion leader:
V. A. Petrov (Logunov IHEP, NRC KI, Protvino)