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The Pauli principle or other fundamental questions: how to test?

The quantum theory has been undergone innumerable experimental tests, all being in agreement with the predictions. However, the quantum theory lacks an explanation of very fundamental principles: such as the famous Pauli exclusion principle holding matter together or why we do not observe superposition of macroscopic objects or why time plays such a different role compared to position. In this talk I will review the basic theoretical concepts and their possibilities for testing.

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“Spring School Colloquium” dei Laboratori Nazionali di Frascati: The SETI Project

Aim of the workshop: Looking for E.T.: The scientific hunt for extraterrestrial intelligence is now well into its fifth decade, and we still haven't uncovered a confirmed peep from any cosmic company. Could this mean that finding aliens, even if they exist, is a project for the ages – one that might take centuries or longer? New technologies for – and new approaches to – the Search forExtraterrestrial Intelligence (SETI) suggest that, despite the continued dearth of signals, there is good reason to expect that success might not be far off – that we might find evidence of sophisticated civilizations within a few decades. What would a contact tell us, and what would it mean to us, and to our descendants?

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Precise top-quark mass determination from energy peaks

We examine the general features of the non-commutativity of the magnetization operator and Hamiltonian for small quantum spin clusters. The source of this non-commutativity can be a difference in the Landé g-factors for different spins in the cluster, XY-anisotropy in the exchange interaction and the presence of the Dzyaloshinskii-Moriya term in the direction different from the direction of the magnetic field. As a result, zero-temperature magnetization curves for small spin clusters mimic those for the macroscopic systems with the band(s) of magnetic excitations, i.e. for the given eigenstate of the spin cluster the corresponding magnetic moment can be an explicit function of the external magnetic field yielding the non-constant (non-plateau) form of the magnetization curve within the given eigenstate. In addition, the XY-anisotropy makes the saturated magnetization (the eigenstate when all spins in cluster are aligned along the magnetic field) inaccessible for finite magnetic field magnitude (asymptotical saturation). We demonstrate all these features on three examples: spin-1/2 dimer, mixed spin-(1/2,1) dimer, spin-1/2 ring trimer. We consider also the simplest Ising-Heisenberg chain, the Ising-XYZ diamond chain with four different g-factors. In the chain model the magnetization curve has a more complicated and non-trivial structure which that for clusters.

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Challenges in the Dark Sector: Alternatives to the WIMP paradigm

Aim of the workshop: Identifying what Dark Matter (DM) is, as well as its nature and properties, remains a major challenge for both theoretical and experimental astroparticle physics communities.  In the past decades, Weakly Interacting Massive Particle (WIMP) DM has been the most hunted candidate, with the result that nowadays WIMPs are cornered by large amounts of experimental data from Direct Detection, Indirect Detection and Collider Experiments.  If no WIMP signal is detected in the next few years, the possibility that this very appealing theoretical idea is not what Nature has chosen will become even more compelling and will boost theoretical studies and experimental searches for non-WIMP alternatives for DM. The aim of this 3-day meeting is to convene experts on alternatives to the WIMP paradigm to stimulate informal discussions on different possibilities  (dark photons, axion-like particles, Majorons, self-interacting dark sectors, just to mention a few). We plan to have only three or four talks each day and plenty of time to discuss implications of these DM scenarios, experimental search strategies, new theoretical proposals, and out-of-mainstream ideas. The general approach and format of the talks will be pedagogical and aimed at favoring extended discussions among all participants.  The audience will range from theorists who are expert on related topics to skillful experimentalists planning new non-WIMP detection experiments, as well as postdocs, graduate students and non-expert colleagues working in different areas. Speakers: J. Beacham (Ohio State U. & CERN) "Lost in a Dark Photon Wood: Searches for hidden light gauge bosons ...

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XVIII FRASCATI SPRING SCHOOL “BRUNO TOUSCHEK” in Nuclear Subnuclear and Astroparticle Physics

Aim of the workshop: 2016 LNF Spring School Frascati, May 9-13, 2016 Lectures are arranged in slots of 1.5 hours, for a total of 14 slots. Time is equally shared between Theoretical and Experimental topics/lectures. Theoretical topics (TL1: 3 lectures; TS2 and TS3: 2 lectures) are matched to related experimental topics (EL1: 3 lectures; ES2, ES3, 2 lectures). The School Program also includes: -Two Sessions of the Young Researchers Workshop: Monday 9th and Thursday 12th , 4.30-6.30pm. -Two Discussion Sessions: Tuesday 10th and Friday 13th , 4.30-6.00pm. -The Spring School Colloquium on Science and Technology: Tuesday 10th , 6.00-7.00pm. Topic No. of Lectures Speaker Theory: TL1: Dark Matter: models and signatures 3 Alejandro Ibarra (Munich, Tech. U.) TS2: Neutrinoless double beta decay: Theory 2 Werner Rodejohann (MPIK, Heidelberg) TS3: Signatures of new physics at LHC 2 Tilman Plehn (Heidelberg U., ITP) Experimental: EL1: Dark Matter: Experimental searches 3 Marc Schumann (AEC, Bern U.) ES2: Neutrinoless double beta decay experiments 2 Stefan Schönert (Munich, Tech. U.) ES3: Searches for new particles at the LHC 2 Oliver Buchmueller (Imp. Coll., London) Spring School Colloquium The SETI Project Explore, understand and explain the origin, nature and prevalence of life in the Universe (Tuesday 10th , 6.00pm) Seth Shostak Senior Astronomer and Director, Center for SETI research SCHEDULE AM PM 9.00-10.30 11.00-12.30 2.30-4.00 4.30-6.00 6.00-7.00 9/5 Mon TL1(DMth) EL1(DMexp) TS2(0n2bTh) Young Reserchers Workshop (4.30-6.30pm) 10/5 Tue TL1(DMth) EL1(DMexp) TS2(0n2bTh) Discussion Session Spring School Colloquium 11/5 Wed TL1(DMth) EL1(DMexp) Excursion 12/5 Thur TS3(MnXth) ES3(MnXEx) ES2(0n2bExp) ...

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THERMAL ENTANGLEMENT & MAGNETIZATION PLATEAUS IN METAL-CONTAINING COMPLEXES

Quantum phase transitions play a key role in the understanding the phenomena of many-body systems, especially in anti-ferromagnetic magnetic plateaus. Thermal entanglement properties in spin-1/2 and spin-1 can be experimentally detected by magnetic susceptibility. The thermal concurrence properties researching of experimental Cu-containing compounds can be observed in diamond chains and polymers. Thermal negativity as a measure of the quantum entanglement is considered in spin-1 Ni-containing complexes.

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Toward a coherent picture of flavour and diphoton anomalies

We propose a coherent explanation for the 750 GeV diphoton anomaly and the hints of deviations from Lepton Flavor Universality in B decays in terms a new strongly interacting sector with vector-like confinement. The diphoton excess arises from the decay of one of the pseudo-Nambu-Goldstone bosons of the new sector, while the flavour anomalies are a manifestation of the exchange of the corresponding vector resonances (with masses in the 1.5–2.5 TeV range). We provide explicit examples (with detailed particle content and group structure) of the new sector, discussing both the low-energy flavour-physics phenomenology and the signatures at high pT. We show that specific models can provide an excellent fit to all available data. A key feature of all realisations is a sizeable broad excess in pp → τ τ (bb), that should be accessible at the LHC in the near future. Based on arXiv:1604.03940

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Collider Phenomenology of Higgs Compositeness

The Higgs naturalness problem can be addressed by considering the Higgs as a composite state emerging from a new strong dynamics. Beside the Higgs, new composite states: vectorlike quarks, vector resonances and new composite scalars, are predicted to exist in the few TeV energy range and to leave observable imprints at the LHC and future colliders. I will discuss their phenomenology, with special focus on the direct detection at colliders.

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From photonic crystals to superconducting nanowires single-photon detectors: fabrication and characterization of devices at the Institute of Photonics and Nanotechnology – CNR in Rome

In this presentation, I will describe different devices fabricated at the Institute of Photonics and Nanotechnology of the National research council in Rome, together with their applications. Special attention will be devoted to electromagnetic radiation detectors and to the realization and characterization techniques used. The devices range from photonic crystals to bolometers for THZ detection, from single photon detectors based on superconducting nanowires to gyroscopes and MEMS for space applications, from microfluidic circuits for biomedical applications to ZnO nanostructures and plasmonic metamaterials. The Institute of Photonics and Nanotechnology in Rome is equipped with a 200m2 clean room. The clean room is provided with all the thin film equipments needed for the micro and nano fabrication of the different devices. The electron beam lithography system allows the patterning of different resists over large areas without using optical masks, with a resolution of less than 100 nm. Further details will be given on single photon detectors based on superconducting nanowires. Such devices are able to detect single photons with high temporal resolution (Jitter of the order of 30-40 ps and dead time of the order of 3-10 ns corresponding to a repetition rate of hundreds of MHz up to a maximum of one GHz). The fabrication process and the devices engineerization allow us to integrate those devices in complex optical circuits and to count up to 24 photons in a single bunch of light.

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Color and the Exclusion Principle

In 1964 I showed that the exclusion principle, which Wolfgang Pauli introduced for electrons in atomic physics, plays an important role in the quark physics of hadrons. Gursey and Radicati placed the ground-state baryons in 56 of SU(6). In the naive quark model this is 3 quarks, each in a 6 of SU(6), in a symmetric state. Since quarks are spin-1/2 particles the quarks should be in an antisymmetric state. To remedy that mismatch I suggested that the fermion quarks carry a new three-valued charge, later called “color,” and that the 56 of SU(6) should also be a singlet of the new SU(3)color . My insistence that the exclusion principle should be obeyed, together with the work of Nambu and Han who gauged SU(3)color in 1965, led to quantum chromodynamics, which is now a central part of the standard model of particle physics.

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