Tue·Oct 5, 2021Tuesday·October 5, 2021

1. 01*

   $K$- and $D_{(s)}$-meson leptonic decay constants with physical light, strange and charm quarks by ETMC

   P. Dimopoulos🇮🇹 · R. Frezzotti🇮🇹 · M. Garofalo🇩🇪 · S. Simula🇮🇹

   We present a lattice QCD computation and preliminary results for the leptonic decay constants of the pseudoscalar mesons $K$, $D$ and $D_s$ in the isosymmetric QCD limit. The computation is based on simulations of $N_f=2+1+1$ dynamical quarks performed by the Extended Twisted Mass Collaboration (ETMC), where the light, strange and charm quark masses are all tuned at their physical values. We also present preliminary unitarity checks for the first and second rows of the Cabibbo-Kobayashi-Maskawa matrix.

   hep-lathep-phPoS(2021)·6 citations
2. 02*

   Investigating the low moments of the nucleon structure functions in lattice QCD

   K. U. Can🇦🇺 · A. Hannaford-Gunn🇦🇺 · E. Sankey🇦🇺 · R. Horsley🇬🇧 · Y. Nakamura🇯🇵 · H. Perlt🇩🇪 · P. E. L. Rakow🇬🇧 · G. Schierholz🇩🇪 · H. Stuben🇩🇪 · R. D. Young🇦🇺 · J. M. Zanotti🇦🇺

   We highlight QCDSF/UKQCD Collaboration's recent developments on computing the Compton amplitude directly via an implementation of the second order Feynman-Hellmann theorem. As an application, we compute the nucleon Compton tensor across a range of photon virtuality at an unphysical quark mass. This enables us to study the $Q^2$ dependence of the low moments of the nucleon structure functions in a lattice calculation for the first time. We present some selected results for the moments of the $F_1$, $F_2$ and $F_L$ structure functions and discuss their implications.

   hep-lathep-phhep-thnucl-thPoS(2022)·3 citations
3. 03*

   Gauge Symmetries, Symmetry Breaking, and Gauge-Invariant Approaches

   Philipp Berghofer🇦🇹 · Jordan François🇧🇪 · Simon Friederich🇳🇱 · Henrique Gomes🇬🇧 · Guy Hetzroni🇬🇧 · Axel Maas🇦🇹 · René Sondenheimer🇦🇹

   Gauge symmetries play a central role, both in the mathematical foundations as well as the conceptual construction of modern (particle) physics theories. However, it is yet unclear whether they form a necessary component of theories, or whether they can be eliminated. It is also unclear whether they are merely an auxiliary tool to simplify (and possibly localize) calculations or whether they contain independent information. Therefore their status, both in physics and philosophy of physics, remains to be fully clarified. In this overview we review the current state of affairs on both the philosophy and the physics side. In particular, we focus on the circumstances in which the restriction of gauge theories to gauge invariant information on an observable level is warranted, using the Brout-Englert-Higgs theory as an example of particular current importance. Finally, we determine a set of yet to be answered questions to clarify the status of gauge symmetries.

   ↳ physics.hist-phhep-lathep-phhep-thElements in the Foundations of Contempora…·14 citations
4. 04*

   Confinement/deconfinement transition in the D0-brane matrix model -- A signature of M-theory?

   Georg Bergner🇩🇪 · Norbert Bodendorfer🇩🇪 · Masanori Hanada🇬🇧 · Stratos Pateloudis🇩🇪 · Enrico Rinaldi🇺🇸 · Andreas Schäfer🇩🇪 · Pavlos Vranas🇺🇸 · Hiromasa Watanabe🇯🇵

   We study the confinement/deconfinement transition in the D0-brane matrix model (often called the BFSS matrix model) and its one-parameter deformation (the BMN matrix model) numerically by lattice Monte Carlo simulations. Our results confirm general expectations from the dual string/M-theory picture for strong coupling. In particular, we observe the confined phase in the BFSS matrix model, which is a nontrivial consequence of the M-theory picture. We suggest that these models provide us with an ideal framework to study the Schwarzschild black hole, M-theory, and furthermore, the parameter region of the phase transition between type IIA superstring theory and M-theory. A detailed study of M-theory via lattice Monte Carlo simulations of the D0-brane matrix model might be doable with much smaller computational resources than previously expected.

   ↳ hep-thhep-latJHEP(2022)·37 citations
5. 05*

   Twisted geometry coherent states in all dimensional loop quantum gravity: I. Construction and Peakedness properties

   Gaoping Long🇨🇳 · Xiangdong Zhang🇨🇳 · Cong Zhang🇵🇱

   A new family of coherent states for all dimensional loop quantum gravity are proposed, which is based on the generalized twisted geometry parametrization of the phase space of $SO(D+1)$ connection theory. We prove that this family of coherent states provide an over-complete basis of the Hilbert space in which edge simplicity constraint is solved. Moreover, according to our explicit calculation, the expectation values of holonomy and flux operators with respect to this family of coherent states coincide with the corresponding classical values given by the labels of the coherent states, up to some gauge degrees of freedom. Besides, we study the peakedness properties of this family of coherent states, including the peakedness of the wave functions of this family of coherent states in holonomy, momentum and phase space representations. It turns out that the peakedness in these various representations and the (relative) uncertainty of the expectation values of the operators are well controlled by the semi-classical parameter $t$. Therefore, this family of coherent states provide a candidate for the semi-classical analysis of all dimensional loop quantum gravity.

   ↳ gr-qchep-latmath-phmath.MPPRD(2022)·14 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.