Special Issue on Spin Statistics

A workshop dedicated to spin statistics—"SpinStat2008"—was held at the end of October 2008 at the Stazione Marittima Conference Center in Trieste, Italy: it was meant to focus especially on experimental and theoretical aspects of the spin-statistics connection and of related symmetries (in particular the CPT and the Lorentz symmetries). The workshop was quite successful and everybody there felt that there should be a follow-up, and that the many interesting contributions and ideas presented there should be put in paper form. After some thinking we decided that the best format would be a series of refereed papers in a topical issue of an outstanding journal, open to all contributors, rather than the usual volume of conference papers restricted to participants. The Editors of Foundations of Physics kindly accepted to host this topical issue, and the ensuing call for papers drew a respectable flow of interesting and novel ideas, and some very appealing review papers. The comments that follow have bee

Snowmass 2021 Topical Report on Synergies in Research at Underground Facilities

This is a Snowmass 2021 Topical Report for the Underground Facilities and Infrastructure Frontier on Synergies in Research at Underground Facilities: A broad range of scientific and engineering research is possible in underground laboratories, beyond the physics-focused activities described in the other Underground Facilities and Infrastructure Topical Reports. These areas of research include nuclear astrophysics, geology, geoengineering, gravitational wave detection, biology, and perhaps soon quantum information science. This UF Topical Report will survey those other scientific and engineering research activities that share interest in research-orientated Underground Facilities and Infrastructure. In most cases the breadth and depth of research aims is too large to cover in completeness and references to surveys or key documents for those fields are provided after introductory summaries. Additional attention is then given to shared, similar, and unique needs of each research area with respect to the broader underground research community's Underground Facilities and Infrastructure needs. Where potential conflicts of usage type, site, or duration might arise, these are identified.Comment: Snowmass 2021 Topical Report (UF5

Performances of an Active Target GEM-Based TPC for the AMADEUS Experiment

In this paper, we present the R & D activity on a new GEM-based Time Projection Chamber (GEM-TPC) detector for the inner region of the AMADEUS experiment, which is aiming to perform measurements of low-energy negative kaon interactions in nuclei at the DAΦNE e+ e- collider at LNF-INFN. A novel idea of using a GEM-TPC as a low mass target and detector at the same time comes motivated by the need of studying the low energy interactions of K- with nuclei in a complete way, tracking and identifying all of the produced particles. Even more, what makes the experimental proposal revolutionary is the possibility of using different gaseous targets without any other substantial intervention on the experimental setup, making it a flexible multipurpose device. This new detection technique applied to the nuclear physics requires the use of low-radiation length materials and very pure light gases such as Hydrogen, Deuterium, Helium-3, Helium-4, etc. In order to evaluate the GEM-TPC performances, a 10 × 10 cm2 prototype with a drift gap of 15 cm has been realized. The detector was tested at the πM1 beam facility of the Paul Scherrer Institut (PSI) with low momentum pions and protons. Detection efficiency and spatial resolution, as a function of gas mixture, gas gain and ionazing particle, are reported and discussed

Studies of discrete symmetries in decays of positronium atoms

A positronium - a bound state of electron and positron - is an eigenstate of parity and charge conjugation operators which decays into photons. It is a unique laboratory to study discrete symmetries whose precision is limited, in principle, by the effects due to the weak interactions expected at the level of 10−14 and photon-photon interactions expected at the level of 10−9. The Jagiellonian Positron Emission Tomograph (J-PET) is a detector for medical imaging as well as for physics studies involving detection of electronpositron annihilation into photons. The physics case covers the areas of discrete symmetries studies and genuine multipartite entanglement. The J-PET detector has high angular and time resolution and allows for determination of spin of the positronium and the momenta and polarization vectors of annihilation quanta. In this article, we present the potential of the J-PET system for studies of discrete symmetries in decays of positronium atoms

Experimental test of Non-Commutative Quantum Gravity by VIP-2 Lead

Pauli Exclusion Principle (PEP) violations induced by space-time non-commutativity, a class of universality for several models of Quantum Gravity, are investigated by the VIP-2 Lead experiment at the Gran Sasso underground National Laboratory of INFN. The VIP-2 Lead experimental bound on the non-commutative space-time scale $\Lambda$ excludes $\theta$-Poincar\'e far above the Planck scale for non vanishing ``electric-like" components of $\theta_{\mu \nu}$, and up to $6.9 \cdot 10^{-2}$ Planck scales if they are null. Therefore, this new bound represents the tightest one so far provided by atomic transitions tests. This result strongly motivates high sensitivity underground X-ray measurements as critical tests of Quantum Gravity and of the very microscopic space-time structure.Comment: 13 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:2209.0007

The effect of spontaneous collapses on neutrino oscillations

We compute the effect of collapse models on neutrino oscillations. The effect of the collapse is to modify the evolution of the `spatial' part of the wave function, which indirectly amounts to a change on the flavor components. In many respects, this phenomenon is similar to neutrino propagation through matter. For the analysis we use the mass proportional CSL model, and perform the calculation to second order perturbation theory. As we will show, the CSL prediction is very small - mainly due to the very small mass of neutrinos - and practically undetectable.Comment: 24 pages, RevTeX. Updated versio