CERN Accelerating science

TH Articles

Latest additions:
2025-05-21
04:14
ADM, BMS, and some puzzling interconnections / Veneziano, Gabriele (CERN ; College de France)
The precise connection between the ADM and BMS formalisms is still far from being fully understood. It leads superficially to some puzzles whose resolution can provide new interesting physical insights. [...]
arXiv:2505.11937; CERN-TH-2025-042.- 2025-05-15 - 14 p. - Published in : J. Phys. A: Math. Theor. 58 (2025) 205402 Fulltext: 2505.11937 - PDF; document - PDF;

Detailed record
2025-04-16
04:04
Comparison of smoothening flows for the topological charge in QCD-like theories / Butti, Pietro (U. Southern Denmark, QTC) ; Della Morte, Michele (U. Southern Denmark, QTC) ; Jäger, Benjamin (U. Southern Denmark, QTC ; U. Southern Denmark, Odense, DIAS) ; Martins, Sofie (U. Southern Denmark, QTC) ; Tsang, J. Tobias (CERN)
We investigate properties of the topological charge for several SU(NC) gauge field ensembles for NC = 4, 5, 6 with a single fermion in the two-index anti-symmetric representation, covering multiple lattice spacings at otherwise approximately constant physical parameters. Comparing the topological charge defined by the Wilson flow and the over-improved DBW2 flow we find that already at small flow times the latter stabilises on discrete values. [...]
arXiv:2504.10197; CERN-TH-2025-079.- 2025-07-01 - 11 p. - Published in : Phys. Rev. D 112 (2025) 014504 Fulltext: 2504.10197 - PDF; document - PDF;

Detailed record
2025-04-12
04:52
Exploratory calculation of the rare hyperon decay $\Sigma^+ \to p \ell^+ \ell^-$ from lattice QCD / Erben, Felix (CERN) ; Gülpers, Vera (Edinburgh U.) ; Hansen, Maxwell T. (Edinburgh U.) ; Hodgson, Raoul (Edinburgh U. ; DESY, Zeuthen) ; Portelli, Antonin (Edinburgh U.)
The rare hyperon decay $\Sigma^+ \to p \ell^+ \ell^-$ is a flavour-changing neutral current process mediated by an $s \to d$ transition that occurs only at loop level within the Standard Model. Consequently, this decay is highly suppressed, making it a promising avenue for probing potential new physics. [...]
arXiv:2504.07727; CERN-TH-2025-055; DESY-25-057.- 2025 - 33 p. - Published in : JHEP 2507 (2025) 038 Fulltext: 2504.07727 - PDF; document - PDF;

Detailed record
2025-04-08
04:07
Inclusive semileptonic decays from lattice QCD: analysis of systematic effects / Kellermann, Ryan (KEK, Tsukuba) ; Hu, Zhi (KEK, Tsukuba) ; Barone, Alessandro (U. Mainz, PRISMA) ; Elgaziari, Ahmed (U. Southampton (main)) ; Hashimoto, Shoji (KEK, Tsukuba ; Sokendai, Tsukuba) ; Kaneko, Takashi (KEK, Tsukuba ; Sokendai, Tsukuba) ; Jüttner, Andreas (U. Southampton (main) ; CERN)
Lattice QCD calculations of inclusive semileptonic decay rates involve new types of systematic effects, such as truncation errors in the estimation of energy integrals, or finite-volume effects for multi-body final states. We investigate them for the lattice data of $D_s \to X_s \ell\nu$ decays, obtained using Möbius domain-wall fermions. [...]
arXiv:2504.03358; KEK-CP-0407; CERN-TH-2025-059.- 2025-07-01 - 56 p. - Published in : Phys. Rev. D 112 (2025) 014501 Fulltext: 2504.03358 - PDF; document - PDF; Publication: PDF;

Detailed record
2025-04-01
04:28
Axial perturbations of black holes with primary scalar hair / Charmousis, Christos (IJCLab, Orsay ; CERN) ; Iteanu, Simon (IJCLab, Orsay) ; Langlois, David (APC, Paris) ; Noui, Karim (IJCLab, Orsay)
We study axial perturbations of static black holes with primary hair in a family of degenerate higher-order scalar-tensor (DHOST) theories. These solutions possess a scalar charge, fully independent of the mass, leading to a continuous one-parameter deformation of the standard Schwarzschild black hole. [...]
arXiv:2503.22348; CERN-TH-2025-058.- 2025 - 38 p. - Published in : JCAP 2505 (2025) 102 Fulltext: PDF;

Detailed record
2025-03-18
04:01
Forecasting constraints on scalar-induced gravitational waves with future pulsar timing array observations / Cecchini, Chiara (Trento U. ; CERN ; INFN, Trento) ; Franciolini, Gabriele (CERN) ; Pieroni, Mauro (CERN)
Pulsar Timing Arrays are playing a crucial role in the ongoing gravitational wave astronomy revolution. The current evidence for a stochastic gravitational wave background (SGWB) at nHz frequencies offers an opportunity to discover cosmological signals and threatens the observability of other subdominant GWs. [...]
arXiv:2503.10805; CERN-TH-2025-045.- 2025 - 19 p. - Published in : Phys. Rev. D 111 (2025) 123536 Fulltext: 2503.10805 - PDF; nxx5-gx7d - PDF;

Detailed record
2025-03-07
04:17
Large charge meets semiclassics in $\mathcal{N}=4$ super Yang-Mills / Brown, Augustus (Queen Mary, U. of London) ; Galvagno, Francesco (Queen Mary, U. of London) ; Grassi, Alba (U. Geneva (main)) ; Iossa, Cristoforo (U. Geneva (main)) ; Wen, Congkao (Queen Mary, U. of London)
We study the large-charge sector of $\mathcal{N}=4$ super Yang-Mills theory (SYM) with $SU(N)$ gauge group by constructing a special class of half-BPS heavy operators, termed "canonical operators". Such operators exhibit remarkable simplicity in the large-charge 't Hooft limit, where the dimension of the operators $\Delta \to \infty$ with $\Delta\, g_{\text{YM}}^2$ held finite. [...]
arXiv:2503.02028; CERN-TH-2025-016; QMUL-PH-25-03.- 2025-06-24 - 49 p. - Published in : JHEP 2506 (2025) 223 Fulltext: 2503.02028 - PDF; document - PDF;

Detailed record
2025-02-25
04:01
Lepton Flavor Asymmetries: from the early Universe to BBN / Domcke, Valerie (CERN) ; Escudero, Miguel (CERN) ; Fernandez Navarro, Mario (Glasgow U.) ; Sandner, Stefan (Los Alamos)
Large primordial lepton flavor asymmetries with almost vanishing total baryon-minus-lepton number can evade the usual BBN and CMB constraints if neutrino oscillations lead to perfect flavor equilibration. Solving the momentum averaged quantum kinetic equations (QKEs) describing neutrino oscillations and interactions, we perform the first systematic investigation of this scenario, uncovering a rich flavor structure in stark contradiction to the assumption of simple flavor equilibration. [...]
arXiv:2502.14960; CERN-TH-2025-010; LA-UR-25-20235.- 2025-06-13 - 42 p. - Published in : JHEP 2506 (2025) 137 Fulltext: 2502.14960 - PDF; document - PDF;

Detailed record
2025-02-18
05:11
The hadronic contribution to the running of $\alpha$ and the electroweak mixing angle / Conigli, Alessandro (Helmholtz Inst., Mainz ; Darmstadt, GSI) ; von Hippel, Georg (U. Mainz, PRISMA) ; Kuberski, Simon (CERN) ; Meyer, Harvey B. (Helmholtz Inst., Mainz ; Darmstadt, GSI ; U. Mainz, PRISMA) ; Ottnad, Konstantin (U. Mainz, PRISMA) ; Wittig, Hartmut (Helmholtz Inst., Mainz ; Darmstadt, GSI ; U. Mainz, PRISMA)
We report on our update to [1] on the hadronic running of electroweak couplings from $O(a)$-improved Wilson fermions with $N_f=2+1$ flavours. The inclusion of additional ensembles at very fine lattice spacings together with a number of techniques to split the different contributions for a better control of cutoff effects allows us to substantially improve the precision. [...]
arXiv:2502.10159; MITP-25-007; CERN-TH-2025-022.- 2025-02-12 - 10 p. - Published in : PoS LATTICE2024 (2025) 287 Fulltext: 2502.10159 - PDF; document - PDF;
In : 41st International Symposium on Lattice Field Theory (Lattice 2024), Liverpool, United Kingdom, 20 Jul - 3 Aug 2024, pp.287

Detailed record
2025-02-18
04:58
Machine-learning techniques as noise reduction strategies in lattice calculations of the muon $g-2$ / Wittig, Hartmut (U. Mainz, PRISMA ; Mainz U., Inst. Phys. ; Darmstadt, GSI) ; Blum, Thomas (Connecticut U.) ; Conigli, Alessandro (Mainz U., Inst. Phys. ; Darmstadt, GSI) ; Geyer, Lukas (U. Mainz, PRISMA) ; Kuberski, Simon (CERN) ; Segner, Alexander (Mainz U., Inst. Phys. ; Darmstadt, GSI ; U. Mainz, PRISMA)
Lattice calculations of the hadronic contributions to the muon anomalous magnetic moment are numerically highly demanding due to the necessity of reaching total errors at the sub-percent level. Noise-reduction techniques such as low-mode averaging have been applied successfully to determine the vector-vector correlator with high statistical precision in the long-distance regime, but display an unfavourable scaling in terms of numerical cost. [...]
arXiv:2502.10237; CERN-TH-2025-038; MITP-25-010.- 2025-02-14 - 9 p. - Published in : PoS LATTICE2024 (2025) 270 Fulltext: 2502.10237 - PDF; document - PDF;
In : 41st International Symposium on Lattice Field Theory (Lattice 2024), Liverpool, United Kingdom, 20 Jul - 3 Aug 2024, pp.270

Detailed record