Searching for the Unexpected at LHC and the Status of Our Knowledge

The following sections are included:

• PREFACE

• CONTENTS

I discuss the main motivations and directions for physics beyond the Standard Model of elementary particles and I give a short introduction on string theory. This theory introduces a new physical constant, the string length, under which a new fundamental structure appears, changing drastically the laws of nature. In particular, lowering the string scale in the Te V region provides a theoretical framework for solving the so-called mass hierarchy problem: the apparent weakness of gravity can be accounted by the existence of large internal dimensions, in the submillimeter region, and transverse to a braneworld where our observed universe is confined. In these lectures, I describe the main properties of string phenomenology with high or low string scale. In the latter case, I discuss also its implications for new gravitational phenomena that can be observed at both particle colliders, and in non-accelerator experiments searching for new short range forces.

The following sections are included:

• Discussion I

• Discussion II

We report on some old and new results on the quantum aspects of four-dimensional maximal supergravity, and its hypothetical ultraviolet finiteness.

The weak bosons are interpreted as composite particles. They consist of two fundamental fermions, bound by a confining gauge interaction. The mass scale of this new interaction is determined. A new neutral isoscalar weak boson X must exist. Its mass is expected to be less than 1 TeV. It will decay mainly into quark and lepton pairs and into two or three weak bosons. Above 1 TeV excitations of the weak bosons must exist, which mainly decay into pairs of weak bosons. Leptons and quarks consist of a fermion and a scalar. Two scalars form bound states, which are either neutral in charge or have charge 2/3 e.

After a short Introduction on beta functions and asymptotic freedom (Lecture 1), the concept of Black Hole Complementarity is introduced, and in connection with that, the importance of local conformal invariance and its spontaneous breakdown (Lecture 2). The emergence of anomalies is discussed, and it is explained that requiring these to cancel out has important implications for model building. In Lecture 3 it is outlined what role the beta functions may play in black hole physics, leading to constraints that make coupling constants, masses, and even the cosmological constant all computable once the algebraical symmetries of a particle model are fixed, although explicit, physically interesting solutions of the resulting equations have not yet been found.

The Gribov approach to the hadron-hadron high energy scattering is based on an effective field theory for Pomerons. We construct similar effective actions for gluons and gravitons in QCD and in gravity. The BFKL approach in QCD is reviewed and presented in the form of the gauge-invariant effective theory for the interactions local in the particle rapidities. An analogous generally covariant action for gravity is formulated in terms of effective currents satisfying the Hamilton-Jacobi equation. It gives a possibility to construct various effective vertices and graviton j-plane trajectory. In the N = 4 extended supersymmetric gauge model such effective action in the 10-dimensional anti-de-Sitter space can be used for the description of the Pomeron interactions.

In this lecture concepts are presented which shall elucidate the set of regularity conditions for gauge fields - connection and curvature - inherent to the dynamics of all local color carrying quanta in QCD at large space - time separations. The regularity conditions do entail dynamical consequences as represented - not exclusively - through the main vacuum condensates for gauge field pairs and for quark antiquark field pairs.

These notes are devoted to the intriguing and still largely unexplored links between String Theory and Higher Spins, the types of excitations that lie behind its most cherished properties. A closer look at higher-spin fields provides some further clues that String Theory describes a broken phase of a Higher-Spin Gauge Theory. Conversely, string amplitudes contain a wealth of information on higher-spin interactions that can clarify long-standing issues related to their infrared behavior.

In the last years we have learnt a lot about neutrino masses and mixings. Neutrinos are not all massless but their masses are very small. Probably masses are small because neutrinos are Majorana particles with masses inversely proportional to the large scale M of lepton number (L) violation, which turns out to be compatible with the GUT scale. We have understood that there is no contradiction between large neutrino mixings and small quark mixings, even in the context of GUTs and that neutrino masses fit well in the SUSY GUT picture. Out of equilibrium decays with CP and L violation of heavy RH neutrinos can produce a B-L asymmetry, then converted near the weak scale by instantons into an amount of B asymmetry compatible with observations (baryogenesis via leptogenesis). It appears that active neutrinos are not a significant component of Dark Matter in the Universe. A long list of models have been formulated over the years to understand neutrino masses and mixings. With the continuous improvement of the data most of the models have been discarded by experiment. The surviving models still span a wide range going from a maximum of symmetry, with discrete non-abelian flavour groups, to the opposite extreme of anarchy.

The following sections are included:

• Discussion

The ISSP 2011 Status Report is a continuation of previous lectures on the QGCW (Quark Gluon Coloured World) Project and can therefore be short, only outlining developments during the last year…

The following sections are included:

• Discussion I

• Discussion II

The following sections are included:

• Discussion

The following sections are included:

• Discussion

The following sections are included:

• Introduction

• Discovery of the QGP

• What’s new at BNL and the RHIC machine this year

• QGP Physics—Highlights from RHIC

• Collective Flow

• RHIC beam energy scan—In search of the critical point

• Hard Scattering as a probe of the QGP

• Anisotropic flow (v₂) of direct-γ

• A charming surprise

• Zichichi to the rescue?

• References

• Discussion I

• Discussion II

The following sections are included:

• Introduction

• Gran Sasso National Laboratory

• Physics at LNGS

• Neutrino project at Gran Sasso

• Study of dark matter

• Conclusion

• References

• Discussion

In their recent paper [1] Alday, Gaiotto and Tachikawa proposed a relation between N = 2 four-dimensional supersymmetric gauge theories and two-dimensional conformal field theories. As part of their conjecture they gave an explicit combinatorial formula for the expansion of the conformal blocks inspired from the exact form of instanton part of the Nekrasov partition function. In this paper we study the origin of such an expansion from a CFT point of view. We consider the algebra A = Vir ⊗ H. which is the tensor product of mutually commuting Virasoro and Heisenberg algebras and discover the special orthogonal basis of states in the highest weight representations of A. The matrix elements of primary fields in this basis have a very simple factorized form and coincide with the function called Z_bif appearing in the instanton counting literature. Having such a simple basis, the problem of computation of the conformal blocks simplifies drastically and can be shown to lead to the expansion proposed in [1]. This paper is review of the work [28].

Supersymmetry is a great idea for new physics, but why should this strange symmetry called R-Parity be exactly conserved?

In fact, even if it is not, we have a very good dark matter candidate in the gravitino and if we are really lucky, the decay products of the gravitino might be detectable by cosmic ray experiments.

In this presentation it is shown that the recent cosmic ray data on positron fraction from PAMELA as well as the electron plus positron data from Fermi LAT, can be well described with decay products from decaying gravitino dark matter. However, if this was really the reason the data looks like it does, one would expect to see something in gamma rays as well. According to Fermi LAT, that something is not seen and although this is not enough to rule out decaying gravitinos as the source of the extra electron-positron pairs seen by PAMELA and Fermi LAT, this explanation is significantly weakened.

Relation between Cosmological Constant and Casimir effect is studied. It is shown that naive calculation for the energy between two plates in flat spacetime has a similar structure to the Casimir energy between two plates in de Sitter spacetime. Last observaton provides us with one more argument in a favor of the idea, that cosmological constant is made of zero modes.

We give a brief overview of some three-dimensional toy models for higher-spin interactions. We first review the construction of pure higher-spin gauge theories in terms of Chern-Simons theories. We then discuss how this setup could be modified along the lines of the known topologically massive theories.

Based on the talk presented at the 49th Course of the International School of Subnuclear Physics, Erice, Italy, 24 June – 3 July 2011

In this talk I describe a new method for organizing Yang-Mills scattering amplitudes that allow the definition of an entire multi-loop scattering amplitude in terms of a small number of “master” graphs. A small amount of information is required from the theory, and constraints propagate this information to the full amplitude. When organized in such away corresponding gravitational amplitudes are trivially found. This talk is based on work[1- 4] done in collaboration with Zvi Bern, Lance Dixon, Henrik Johansson, and Radu Roiban, and follows closely the presentation given in ref. [5].

We propose for the first time a method to perform analysis of time-dependent CP asymmetries in charm by using both, correlated and un-correlated D⁰ mesons. Here we consider the decay channels D⁰ → K⁺ K⁻ and D⁰ → π⁺π⁻. The channel D⁰ → K⁺ K⁻ will be used to measure the mixing phase, and the difference between the measured phase D⁰ → K⁺ K^→ and D⁰ → π⁺π⁻ will open the door to the first measurement of β_c, one of the angle of the charm unitarity triangle. Since in the standard model CP asymmetries in charm are expected to be small, any observation of large time dependent asymmetries or mismatch between predicted and observed value for β_c could signify new physics. We perform and show results of numerical analysis made considering Super B running at charm threshold, Super B running at ϒ(4S) and LHCb and find that Super B and LHCb will be able to measure β_c,eff with a precision of 1.3° and 1.4° respectively. The same analysis shows that ϕ_MIX could be measured at Super B with a precision of 1.3°.

It is reported on a subtle aspect of gated multi-wire proportional chambers (MWPCs) that was recently observed in the read-out chambers of the ALICE TPC: periodic switching of the gating grid causes sizable (order of 10 pm) mechanical oscillations of its wires. Moreover, theses oscillations resemble themselves as a systematic pick-up signal on the data with signal heights comparable to those of minimum-ionising particles.

Positronium is an ideal system for the research of QED in a bound state. The hyperfine splitting of positronium (Ps-HFS: about 203 GHz) is a good tool to test QED, and is also sensitive to new physics beyond the Standard Model. Previous experimental results of Ps-HFS show 3.9 σ (15 ppm) discrepancy from the QED prediction up to O (α³ ln 1/α). A first direct Ps-HFS measurement without one of the systematic uncertainties is proposed in this paper. This measurement needs progress of technology in sub-THz region. The technology for sub-THz and THz is still under development, which is called terahertz gap. Technological innovation can create a new probe for the totally unexpected. By developing three key devices in sub-THz region, the direct transition between ortho-positronium and para-positronium was observed for the first time with 5σ. The current status and future prospect are explained.

The following sections are included:

• Introduction and Motivation

• The MINOS Experiment

• Neutrino Interactions in the MINOS Detectors

• The Analysis

• References

• The Future of θ13

• Acknowledgments

The Daya Bay reactor neutrino experiment is designed to precisely measure a new mode of the neutrino oscillation between ν₁ and ν₁₃, which is often referred as the neutrino mixing angle θ₁₃. The experiment deploys multiple identical detectors underground at different baselines to reduce the systematic errors and suppress cosmogenic backgrounds. The construction of the experiment is currently close to completion, and the data taking is planned for this summer. A brief overview and the progresses of this experiment will be reported.

The following sections are included:

• DIPLOMAS

• AWARDS

• PARTICIPANTS