Tag Archives: Evento scientifico

Chaired by Roberto Saban (PRESID)

We consider Extended Theories of Gravity and in particular, models containing scalar-tensor and higher-order curvature terms, as well as models derived from fundamental theories like Non-commutative Spectral Geometry. In the weak-field approximation, we take into account the geodesic and Lense-Thirring processions, deriving constraints on the free parameters by the experimental data on Solar System scales. The main result of this research is that constraints on fundamental theories of gravity can be achieved at local scales and compared with cosmic data.

Pseudoscalar QCD axions and axion-like Particles (ALPs) are an excellent candidate for Dark Matter or can act as a mediator particle for Dark Matter. A look at the allowed axion/ALP parameter space makes it clear that these might exist at low mass (below few eV), as (part of) Dark Matter. Alternatively they might exist at higher mass, above roughly the MeV scale, potentially as a Dark Matter mediator particle. In this talk I review most prominent techniques and experiments searching for Axions and ALPs and will present in more detail efforts taking place at CERN.

On August 17th, 2017, a new era in the multi-messenger astronomy has started. The detection of gravitational waves produced by the merging of two neutron stars with three detectors (the two Advanced LIGO and Advanced VIRGO) has allowed the source localization, making possible the observation of the electromagnetic follow-up by many telescopes around the world. This mini-workshop will deal with the detection of the event as well as with its scientific impact on different fields, ranging from gravitational waves to astrophysics.

We propose a model for dark matter, which in principle ONLY use the Standard Model, although it only works under use of speculated NONPERURBATIVE effects. In this model the dark matter consists of insect sized pearls or better bubbles made from a different phase of vacuum (“condensate vacuum”) consisting of a fluid of top and anti top quarks – likely in the form of bound states of 6 top + 6 anti top quarks – pumped up by usual atoms under very high pressure to compensate the very strong surface tension of the bubbles. We take as fitted values of the size of the bubbles a diameter of 1 cm and a mass of $10^8$ kg, and correspondingly the distance between the individual bubbles is between our distance to the moon and to the sun. Impacts – one about every century – would fit with causing the special type of volcanoes called kimberlite pipes, of which there are about 6500 known on the earth. In the supernova SN1987A in the Large Margellanic Cloud there were observed a controversial neutrino signal in Mont Blanc by LSD about 5 hours before the main neutrino burst observed later; this is speculated to be due to our pearls.

Much of the community has been exploring exotic solutions for the UV completion of gravity. I am interested in exploring a different possibility, that of an asymptotically free quantum field theory. There are obstacles of course, and the talk will be a discussion of the problems and a possible pathway through them.

Aim of the workshop: In spite of its consolidated experimental success, the Standard Model of particle physics falls short of describing all observed phenomena. Elegant and well motivated theoretical ideas, such as Supersymmetry, Technicolor or Grand Unification, have so far found no support from experimental results. The longed-for discovery of some kind of physics beyond the Standard Model, that could guide us to replace these ideas with new theoretical paradigms, has so far escaped all experimental efforts. Given this situation, any serious attempt to approach the incompleteness of the Standard Model from originally different and unconventional perspectives should receive proper consideration. Fearless exploration outside the box might provide more insights than lengthy struggles through standard thinking. During this 3-day workshop we plan to review some recent attempts to approach fundamental physics issues from non standard perspectives. We plan to have only two or three talks each day and plenty of time to analyze jointly the good and bad of the various proposals, confront ideas and discuss. Scientific Program and Speakers: John Donoghue (Massachusetts U., Amherst) “Quantum Field Theory for Gravity” Gia Dvali  (LMU, ASC & MPI, Munich & NYU, CCPP, New York)  “Classicalization” Renate Loll (Radboud U., NL) “Quantum Gravity, or: Give me (more) observables!”  Matthew McCullough  (CERN) “Hyperbolic Higgs, Clockwork and Relaxion” Holger F.B. Nielsen (Bohr Inst.) “Dark Matter, Double Supernova Neutrino Explosion, Degenerate Vacua, Predetermination? Why the SM Group?” Roberto Percacci  (SISSA)    “Asymptotic Safety” Eugenio Bianchi  (Penn State) “Entanglement in Loop Quantum Gravity”  Michael Spannowsky  (Durham U. & Durham U., IPPP) “Higgsplosion, Higgspersion …

Modern developments in hadron physics emphasize the role of parton intrinsic motion and spin, and their correlations, which are crucial to our full understanding of the nucleon structure in terms of the quark and gluon degrees of freedom in QCD. The main aim of the workshop is to provide an environment in which present theoretical and experimental knowledge in the field of transversity, transverse-momentum dependent distribution and fragmentation functions as well as generalized parton distribution functions will be presented and discussed in depth, together with new theoretical ideas and experimental perspectives. The scientific program will consist of presentations (by invitation only), featuring review talks (30 minutes + 10 minutes for discussion) and research talks (20 minutes + 5 minutes or 15 minutes + 5 minutes for discussion). In addition a round-table will be devoted to the perspectives of the field. The Workshop follows the successful editions held in : 2005 on Lake Como (Italy), 2008 Ferrara (Italy), 2011 in Losinj (Croatia), 2014 Cagliari (Italy).

FAMU will realize the first measurement of the hyperfine splitting (hfs) in the 1S state of muonic hydrogen ΔEhfs(μ-p)1S – providing crucial information on proton structure and muon-nucleon interaction – by using an intense pulsed muon beam, and an on-purpose developed high-energy mid infrared tunable laser. FAMU initiates a new class of experiments representing a significant leap forward in the quality of spectroscopic measurements in muonic atoms; specifically, it will provide the proton Zemach radius rZ with higher precision than previously possible, disentangling discordant theoretical values and will quantify any level of discrepancy that may exist between values of rZ as extracted from normal and muonic hydrogen atoms. It will set a needed cornerstone result about not yet explained anomalies within the proton charge rch radius. The Zemach radius rZ and the r.m.s charge radius rch are the only proton shape-related values that can be directly extracted from experimental data, and rZ is the only one that carries information about the proton’s magnetic dipole moment distribution. A pulsed intense muon beam entering the MUST hydrogen gas target will form muonic hydrogen atoms. FAMU’s theoretical and experimental effort will establish new limits on the proton structure parameters measuring the muonic hydrogen transition ΔEhfs(μ-p)1S with unprecedented precision – δλ/λ < 10-5 – and will shed light on the low momentum limit of the magnetic-to-charge form factor ratio.