iten
Home » Evento

Tag Archives: Evento scientifico

Workshop Quantum Foundations. The physics of “what happens” and the measurement problem

This workshop is organized in the framework of the Foundational Questions Institute, FQXI, project: “Events” as we see them: experimental test of the collapse models as a solution of the measurement problem, and is sponsored by INFN. The aim of the workshop is to discuss the possible limits of validity of quantum mechanics, the collapse models and, more generally,  theories which go beyond the standard quantum mechanics, as well as experiments aiming to test them. Also, in this context, the role that gravity may play will be discussed. From the theoretical point of view, since the Einstein-Bohr debate, quantum mechanics never stopped raising questions about its meaning. In particular, the transition from the microscopic world, where systems are observed in a superposition of different quantum states, to the macroscopic world, where systems have well defined positions (the so-called “measurement problem”), never stopped to puzzle the scientific community. For this reason, scientists are pushed to look for theories beyond the standard quantum formulation. From the experimental point of view, quantum mechanics is the best verified available theory. It is therefore a very compelling challenge to look for possible small violations predicted by alternative quantum theories. The aim is either to put stronger observational bounds on the new theories, i.e. on model's parameters, or, much more exciting, to find a violation of standard quantum mechanics when compared with the new theories' predictions. In this framework, a deeper understanding of the possible limits of validity of the quantum superposition principle is an interesting ...

Scopri di più »

Hot QCD Matters

Aim of the workshop: Strongly-interacting matter at extreme conditions of temperature and density is a major subject of research in both theoretical and experimental communities. Experiments with ultra-relativistic nuclei at RHIC and LHC create matter at extremely high temperatures, where quark-gluon plasma is formed and studied, reproducing in laboratory conditions which were realized  in the Early Universe. According to the Big Bang Theory this state of matter existed in the Universe roughly between 20 pico-s and 20 micro-s after the BigBang. At a very high density, a cold quark-gluon plasma as well as other exotic phases (quarkyonic, color superconducting) might exist in the core of neutron stars, outside the reach of current experiments. The analysis of strongly-coupled systems requires non-perturbative methods such as lattice QCD or functional renormalization group. These studies have provided information of the phases and thermodynamics of QCD at equilibrium. On the other hand, the state of matter produced in ultra-relativistic heavy-ion collisions reaches equilibrium only for a very short time. It is a major challenge of contemporary studies to develop theoretical and phenomenological tools which link the experimental observations with the predictions of the fundamental theory at equilibrium. The aim of this 3-day meeting is to convene experts to stimulate an informal discussion on hot QCD and related topics. We plan to have only three talks each day, and plenty of time to discuss some of the open issues in heavy-ion theory and measurements. The equation of state of nuclear matter and its relation with the ...

Scopri di più »

A Rare Opportunity – the Mu2e experiment at Fermilab

Quarks and neutrinos are known to change flavors, but what about the charged leptons? The proposed Mu2e experiment at Fermilab will offer a sensitivity to charged-lepton flavor violating processes four orders of magnitude better than anything to have come before it. This extraordinary improvement in sensitivity will give Mu2e significant discovery potential over a wide range of new physics models. Moreover, Mu2e probes for this new physics in a manner complementary to the rest of the world’s HEP physics program at effective mass scales approaching 10,000 TeV. The physics motivations, design sensitivity, and status of the Mu2e experiment will be presented.

Scopri di più »

MUSE General Meeting

2017 Annual General Meeting reviewing the activities supported by the MUSE project. MUSE is a EU funded project under the Horizon 2020 Research and Innovation program, Grant Agreement 690835. It coordinates the activities of about 70 researchers from various European research institutes (INFN, University College London, University of Liverpool, Helmholtz-Centrum Dresden-Rossendorf, Fermilab) and industries (PRISMA, CAEN, AdvanSid) for the participation to the experiments at the Muon Campus of the Fermi National Laboratory (FNAL), in USA. The meeting will be held at the Frascati National Laboratory of INFN.

Scopri di più »

The shape of (new) physics in the B decay anomalies

High-precision measurements of flavour-changing processes are sensitive to the virtual effects of particles at energies beyond the reach of current colliders; thus, any New-Physics addressing the hierarchy problem of the electroweak scale must have a non trivial structure in flavour space to avoid all the stringent flavour constraints. In fact, although no new heavy particles have been identified in the high-energy frontier yet, there are tantalizing tensions with the SM in B-meson decays measured at the LHCb and B factories. The first type of anomalies appear in observables of the FCNC rare b→s ll decays, like in the angular distributions of B→K*μ μ, or in the ratio RK = Γ(B→K μ μ) / Γ(B→K e e) . These are currently in 4σ tension with the SM, putatively corresponding to the tree-level exchange of a neutral particle with mass Λ ~ 10 TeV selectively coupling to muons. The second type of anomalies appear in the CC b→ c τ ν transitions which have been measured through the ratios RD(*) = Γ(B→D(*) τ ν)/ Γ(B→D(*) l ν), where l is the muon or the electron. The average of the measurements is enhanced with respect to the SM and it would correspond to the tree-level exchange of a charged particle with mass Λ ~ 1 TeV and coupled selectively to τ leptons. In this talk I will review these decays, discussing the extent up to which the SM predictions are understood and the type of new physics one would need to explain the ...

Scopri di più »

A new approach to the physics of complex systems

Recent theoretical developments highlight a set of shared principles underpinning macroscopic quantum coherence in high temperature superconducting (HTSC) materials and the emergence of long-range order and macroscopic quantum coherence phenomena such as photosynthesis in biological structures. Preliminary investigations suggest that the emergence of functionality and structure in these systems is driven by dissipative processes, which lead to fractal assembly and a fractal network of charges (with associated quantum potentials) at the molecular scale. At critical levels of charge density and fractal dimension, a percolation threshold is reached where individual quantum potentials merge to form an infinitely interconnected `charged-induced’ macroscopic quantum potential (MQP), which can be viewed as a macroscopic path integral. The process by which a MQP acts as a structuring force (in competition with environmental perturbation) dictating the emergence of structure and function in biological and inorganic systems will be described within the context of a new set of macroscopic quantum mechanics processes. Specific issues to be highlighted include the emergence of different phases (coherent electron pairs, Charge Density Waves and Spin Density Waves) observed in complex HTSC materials. The macroscopic quantum processes that underpin these different phenomena will be compared and contrasted with standard quantum mechanics to highlight the extent of commonality (and key differences) between the two quantum systems. Within the context of these new theoretical developments we consider a new experimental approach to the development of inorganic structures and macroscopic coherent systems, analogous to those emerging through biological processes. It is anticipated that this work will ...

Scopri di più »

The Precision Proton Spectrometer at the LHC

The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) is an approved project to add tracking and timing information at approximately ±210~m from the interaction point around the CMS detector. It is designed to operate at high luminosity with up to 50 interactions per 25~ns bunch crossing to perform measurements of e.g. the quartic gauge couplings and search for rare exclusive processes. During 2016, CT-PPS took data in normal high-luminosity proton-proton LHC collisions. In the coming years, high radiation doses and large multiple-vertex interactions will represent difficult challenges that resemble those of the high-luminosity LHC program. A coordinated effort of detector upgrades with the goal of reaching the physics goals while mitigating the degradation effects is under way. The ongoing program, including the status and the planned upgrade projects for the tracking and timing detectors are discussed.

Scopri di più »

Hidden symmetries of deformed oscillators

We associate with each simple Lie algebra a system of second-order differential equations invariant under a non-compact real form of the corresponding Lie group. In the limit of a contraction to a Schrodinger algebra, these equations reduce to a system of ordinary harmonic oscillators. We provide two clarifying examples of such deformed oscillators: one system invariant under SO(2,3) transformations, and another system featuring G2(2) symmetry. The construction of invariant actions requires adding semi-dynamical degrees of freedom; we illustrate the algorithm with the two examples mentioned.

Scopri di più »

The QCD axion, precisely

The QCD axion is probably the most robust solution to the strong CP problem and a natural dark matter candidate. While its properties, such as the mass and the couplings, are mostly determined by non-perturbative QCD effects I will present recent computations demonstrating that they can be reliably extracted with percent accuracy, which is important for the theory interpretation of experimental results. I will also discuss some recent lattice QCD results highlighting a departure from the usual instanton estimates and potentially changing the prediction for the axion relic abundance substantially. In this seminar I will discuss what changes to analysis strategy and detector setup will be necessary to definitively discover or exclude the experimentally-elusive pure-higgsino thermal relic at the FCC, thus closing the window on neutralino dark matter.

Scopri di più »