Modeling matter at high densities, high temperatures, and at large values of the relevant coupling constant(s) is a quite challenging task. In these lectures, we are going to introduce the AdS/CFT correspondence (more generally called gauge/gravity correspondence or holography), which allows us to map challenging quantum problems at strong coupling to classical gravity problems at small...
Modeling matter at high densities, high temperatures, and at large values of the relevant coupling constant(s) is a quite challenging task. In these lectures, we are going to introduce the AdS/CFT correspondence (more generally called gauge/gravity correspondence or holography), which allows us to map challenging quantum problems at strong coupling to classical gravity problems at small...
Starting from model Lagragians of the Nambu-Jona-Lasinio(NJL) type that share basic symmetries with the QCD Lagrangian we demonstrate in these lectures how to use the Path-Integral formalism in order to obtain dynamical chiral symmetry breaking and color superconductivity at the mean-field level of description and how to describe the formation and dissociation of hadronic bound states of...
Starting from model Lagragians of the Nambu-Jona-Lasinio (NJL) type that share basic symmetries with the QCD Lagrangian we demonstrate in these lectures how to use the Path-Integral formalism in order to obtain dynamical chiral symmetry breaking and color superconductivity at the mean-field level of description and how to describe the formation and dissociation of hadronic bound states of...
We discuss different approaches to model various stage of relativistic heavy ion reactions. We will start from straightforward hydrodynamic descriptions and will then turn to multi-fluid hydrodynamics and hybrid approaches where a Boltzmann transport equation is coupled to hydrodynamics. The main physics results are discussed with a focus on elliptic flow and di-lepton production.
We discuss different approaches to model various stage of relativistic heavy ion reactions. We will start from straightforward hydrodynamic descriptions and will then turn to multi-fluid hydrodynamics and hybrid approaches where a Boltzmann transport equation is coupled to hydrodynamics. The main physics results are discussed with a focus on elliptic flow and di-lepton production.
A remarkable breakthrough in neutrino physics has been witnessed in recent years. Neutrino oscillation experiments have firmly established the existence of neutrino masses and leptonic mixing, which represents a solid evidence of physics beyond the Standard Model. We present a brief overview of the neutrino flavor puzzle, with emphasis on theoretical approaches to address this problem. A...
A curious uniformly accelerated point charge, which moves neither in a straight line nor in a circle, but in a cusp, is investigated. We ?find the angular distribution of the Larmor radiation, the constant power, and the intensity in the maximal direction. We also confirm that the vacuum excitation spectra of quantized field detectors on the world line is analytic and hotter than rectilinear...
Magneto-elastic Oscillations of neutron stars are believed to be observed as quasi-periodic oscillations in the decaying tail of the giant flares of magnetars. Significant efforts in the theoretical modelling from different groups have increased our understanding of this phenomenon significantly. Here we will discuss some constraints on the matter in neutron stars that arise if the...
The IceCube Neutrino Observatory, located at the geographical South Pole, has a rich scientific program covering a wide range of topics from multi-messenger astrophysics to particle physics. Evidence for the existence of an astrophysical flux of neutrinos was presented in 2013, opening a new window into the cosmos. Since then, a variety of follow-up studies have strengthened the case. Neutrino...
The last decade was remarkable for neutrino physics. In particular, the phenomenon of neutrino flavor oscillations has been firmly established by a series of independent measurements. All parameters of the neutrino mixing are now known and we have elements to plan a judicious exploration of new scenarios that are opened by these recent advances. With precise measurements we can test the...
The long baseline neutrino community is constructing a 40 kiloton liquid argon imaging detector at the Sanford underground research facility in South Dakota about 1300 km from Fermilab. The primary goal of this project is to study the evolution of the neutrino beam to determine the neutrino mass hierarchy and CP violation in the neutrino sector. Additional goals include studies of proton...
The Pierre Auger Observatory is currently the world's largest cosmic ray observatory, designed to explore the energy range from $10^{17}\,\mathrm{eV}$ up to and beyond $10^{20}\,\mathrm{eV}$. This also provides us with access to center of mass energies for particle collisions beyond those available to current accelerators. We will present recent results from the Pierre Auger Observatory, which...
The QCD matter produced initially in ultra-relativistic nucleus-nucleus collisions is expected to represent a high temperature plasma, which should be evidenced in its electromagnetic radiation. We analyze the production of real and virtual photons from the strongly-coupled QGP in the initial stages of the collisions as well as the ('corona') radiation from the interacting mesons and baryons...
I present a new transport approach for heavy ion collisions based on a n-body transport theory and called PHQMD. In contradistinction to all other approaches it allows to study the production of fragments as well as of hypernuclei in the energy range from $E_{Lab} =500$ AMeV to $\sqrt{s} = 13$ TeV. First tests show that indeed fragments are product at all energies ( as seen experimentally) and...
We present recent results on the sub- and near threshold production of multi-strange hadrons and of charmed hadrons. These particle allow to explore multi-step processes in dense hadronic matter. We provide an alternative explanation for the observed transparency ratios of Phi-mesons and show how the observed enhanced Cascade production at HADES energies can be explained. For the near and...
Ultra-relativistic collisions of heavy nuclei at the Large Hadron Collider (LHC) at CERN in Geneva (Switzerland) and the Relativistic Heavy Ion Collider (RHIC) in New York (US) create sufficiently high temperatures that nuclear matter melts into a “soup” of quarks and gluons called the quark-gluon plasma (QGP). Thousands of particles and anti-particles are created in a single event with...
The flux of cosmic ray antiproton is a powerful tool for indirect detection of dark matter. The sensitivity is limited by the uncertainty on the predicted antiproton flux from scattering of primary protons on the interstellar medium. This is in turn limited by the knowledge of antiproton production cross sections, notably in p-He scattering. Thanks to its internal gas target SMOG, LHCb...
In this contribution, a model to explain color transparency in QCD is discussed. This model focuses on recreating the interaction of color dipole created from the quantum oscillations of the virtual photons of high energies that intervene in the ultra-peripheral collisions as a consequence of its exchange with the vacuum presented in the VDM model. The interaction of the small size...
In order to prove the existence of a critical end point (CEP) in the QCD phase diagram it is sufficient to demonstrate that at zero temperature $T=0$ a first order phase transition exists as a function of the baryochemical potential $\mu$, since it is established knowledge from ab-initio lattice QCD simulations that at $\mu=0$ the transition on the temperature axis is a crossover.
We present...
By starting with a seed Newtonian potential-density pair we construct axisymmetric and spherical relativistic sources for a Majumdar-Papapetrou type conformastatic spacetime. As a first example, we consider a family of Plummer-Hernquist type relativistic spherical sources (G. García-Reyes, Gen. Relativ. Gravit. 49, 3, 1-13 (2017)), and as a second application we construct relativistic...
We explore the existence of stealth configurations in a modified gravity model including a linear coupling between a scalar field and the Gauss–Bonnet invariant.
We examine the relation between non-perturbative General Relativity, cosmological perturbations (linear and non-linear) and Newtonian gravity by means of an exact non-spherical solution of Einstein's equations (the Szekeres models) that allows for a non-trivial modeling of realistic cosmic structure. We show that the exact dynamics of cosmological perturbations for dust sources (at all...
A short review on the pseudo-complex General Relativity will be presented. Some predictions of the theory will be given and compared to the standard General Relativity. First, accretion disks around SrgA* and the black hole in M87 will be given, at the used observation frequency. Second, a comment will be given on the observation of gravitational waves, related to their origin.
We derive the generic portion of the theory of General Relativity which emerges by presuming merely the action principle and the general principle of relativity to hold. Hence, we isolate those physical theories whose action functional is invariant in its form under arbitrary transformations of the reference frame. Transformations of the dynamical variables which maintain the form of the...
Matter at the highest baryon compression is transiently formed and can be probed directly in both, relativistic collisions of two neutronstars (NS- mergers) and in relativistic collisions of two heavy ions. Observables sensitive to the properties of superdense matter, like flow and yields of ejected particles (nuclei, strange hadrons, neutrinos, photons, dileptons) are since recently...
CTA is a global initiative to build the world’s largest and most sensitive very high-energy gamma-ray observatory. To this end a consortium of participating institutions, bringing together scientists from 32 countries, has been set up. The Cherenkov Telescope Array will provide unprecedented opportunities for observing the energetic universe in the “Tera electron Volt window,” which will...
I will present the latest results on Ultrahigh Energy Cosmic Ray observations from the Telescope Array observatory. This will include measurement of the flux spectrum, the chemical composition and searches for anisotropy. In particular, the status of the TA "hot spot" will be discussed and how events in the hot spot region contribute to the flux spectrum.
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian Spektrum-Roentgen-Gamma (SRG) mission which is currently scheduled for launch in fall 2017. eROSITA will perform a deep survey of the entire X-ray sky. In the soft band (0.5-2 keV), it will be about 30 times more sensitive than ROSAT, while in the hard band (2-8 keV) it will provide the...
We have revisited the all-sky survey carried out by the ROSAT satellite, to create a new image of the sky at X-ray wavelengths. Along with this, a revised and extended version of point-like sources has been released. The now published 2RXS catalogue provides the deepest and cleanest X-ray all-sky survey to date, which will only be superseded with the launch of the next generation X-ray survey...
The Chinese-French space mission SVOM (Space-based multi-band astronomical Variable Objects Monitor) is mainly designed to detect and localize Gamma-Ray Burst events (GRBs). The satellite, to be launched late 2021, embarks a set of gamma-ray, X-ray and optical imagers. Thanks to its pointing strategy, quick slew capability and fast data connection to earth, ground based observations with large...
We constrain the dust-to-gas ratio in the intergalactic medium (IGM) at high redshifts. We employ models for dust in the local universe to constrain the dust-to-gas ratio during the epoch of reionization at redshifts z~6-10. The observed level of reddening of high redshift galaxies implies that the IGM was enriched to an intergalactic dust-to-gas ratio of less than 3% of the Milky Way value by...
After a brief introduction to QCD at small $x_{Bj}$ we show that the wave function of a hadron or nucleus at small $x$ contain a large number of gluons. We argue that this kinematics dominates high energy scattering and that the hadron/nucleus can be describes as a strong classical color field from which a parton in the projectile scatters. We apply this formalism to particle production in...
Do you want to work with a really physical theory? Then your theory must be free of any kind of instability or pathology. Therefore you must, at least, work with a Galileon action. Galileons are scalar fields in a curved background whose action is built so that the field equations are second-order and the number of propagating degrees of freedom is the right one. We have built recently the...
We study a scale-dependent gravitational model coupled to a nonlinear electrodynamic source. An analytic black hole solution is obtained which differs from the classical model in which the scale dependence is absent. Certain properties, such as horizon structure and thermodynamics are discussed.
A semiclassical statistical mechanical approach to black hole entropy based on Van der Waals horizon thermodynamics for the Schwarzschild–de Sitter solution has been developed. Emphasis on the emergence of spacetime atoms and their relationship with particular observers have lead us to propose a simple physical model through which areas are quantized in accordance with other approaches.
We present the derivation and the solutions to the coupled electromagnetic and gravitational perturbations with sources in a charged black hole background. We consider as source of the perturbations the infall of radial currents. In this way, we study a system in which it is provoked a response involving both, gravitational and electromagnetic waves, which allows us to analyze the dependence...
We briefly review the holographic (gauge/gravity correspondence) techniques allowing to study strongly coupled systems far from equilibrium and near equilibrium. Then we compute the quasi-normal mode frequencies of gauge field and metric perturbations around black branes which are electrically and magnetically charged. By use of the gauge/gravity correspondence, these fluctuations are dual to...
We investigate the Quantum Faraday Rotation starting from the photon self-energy in the presence of a constant magnetic field. The angle is calculated for a weak non degenerate limit for engage a discussion related to the constraints of the magnetic field constraints imposed by Planck. The origin of the Faraday angle is studied and is compared with classical limit.
We study the chiral effects in QED in the magnetized vacuum and medium. We report the generation of a pseudovector electric current having imbalanced chirality in an electron-positron strongly magnetized gas in QED. It propagates along the external applied magnetic field B as a chiral magnetic effect in QED. It is triggered by a perturbative electric field parallel to B, associated to a...
We analyze the decay of a heavy scalar boson to two light charged scalars, in presence of a uniform, constant magnetic field. The effect of magnetic fields on a particle decay process have been studied in many contexts, in presence of different ingredients and with a variety of methods. We will review here some results that can be found in the literature, discussing their differences. We then...
Beta disintegration is studied in the presence of a magnetic field, which imposes a preferential direction on the emission of neutrinos. It is explored the possibility that this anisotropy in neutrino emission can account for observed Neutron (Quarks) Star velocities (kicks). The conditions under which the anisotropic emission of neutrinos (due to the magnetic field present in the system)...
We report a realistic calculation of the magnetic field profile for the equation of state inside strongly magnetized neutron stars. Unlike previous estimates, which are widely used in the literature, we find that magnetic fields increase relatively slowly with increasing baryon chemical potential (or baryon density) of magnetized matter. More precisely, the increase is polynomial instead of...
We present a new numerical tool to calculate the emission of highly magnetized neutron stars (magnetars) and apply it to describe the quasi-periodic oscillations (QPOs) observed in magnetar giant flares. In previous work we have developed a model of magneto-elastic oscillations of magnetars that allows to reproduce the observed frequencies. These QPOs can couple to the star’s exterior through...
I will review the very best limits on cosmological magnetic fields, and how these limits can be improved with future-generation facilities. Cosmological (extragalactic) magnetic fields are bound to be weaker than around 1 nG, coherent across a Jeans' length. These limits are obtained from rotation measures data, and as such they do not depend on the epoch at which the fields were generated.
We derive a relativistic model of matter-wave duality. The model turns out to be qualitatively similar to the well-known de Broglie-Bohm's model. It prescribes that the total energy of a body in a state of motion relative to an observer, is carried cooperatively by the body corpuscular matter, and its dual wave. At very low velocities (β <<1), the wave component diminishes, and the body total...
The ghost-free massive spin-2 field of bigravity turns out to be an amusing Dark Matter candidate. I will review the theoretical foundations of bigravity, and outline the qualities and phenomenology of spin-2 gravitational dark matter.
Here, we review the use of the Ep,i-Eiso correlation of GRBs to measure the cosmological density parameter $\Omega_M$. We show that the present data set of GRBs, coupled with the assumption that we live in a flat universe, can provide independent evidence, from Supernovae-Ia, that $\Omega_M \sim 0.3$. We show that current (e.g. Swift, Fermi/GBM, Konus-WIND) and forthcoming gamma ray burst...
The Planck data on the CMB power spectrum marginally support deviations from scale invariance at several multipole ranges. We examine the implications of such features for the scalar bispectrum and the tensor power spectrum providing several consistency relations and templates while highlighting the power of joint analysis of spectra in search for features.
We present static spherically symmetric solutions of the equations of motion of a scalar field interacting with gravity (EKG equations) in the Colombeau-Egorov's sense of generalized functions. The scalar fields are confined within the interior region and the exterior fields are purely gravitational and coinciding with the Schwarzschild ones. The solution resembles the so called "gravastars"...
In this work, we present a possible interpretation for very small braking index of PSR J1734-3333, which challenges the current theories of braking mechanisms in pulsars, and estimate some initial parameters. According to our suggestions, this pulsar could be born with a superhigh internal magnetic field ~ $10^{14} -10^{16}$ G, and could undergo a supercritical accretion soon after its...
With a compactness slightly smaller than that of the black hole, pulsar provides a perfect natural laboratory for us to learn gravity and strong interaction. However, due to non-perturbative effect of strong interaction at low energy levels, it's impossible to verify the interior structure of compact stars from QCD calculations. Therefore, the equation of state of dense matter such as compact...
The strangeon (strange nucleon) matter is sometimes denounced for “superluminal” due to its stiff matter state. However, in this paper, we obtain a new expression of sound speed with the method in control theory, and show that even in such stiff matter, the signal propagation speed is still less than speed of light. Then, the “superluminal” problem no longer exists, and the pulsar can...
Although the detailed structure of neutron stars remains unknown, their equilibrium temperatures lie well below the Fermi temperature of dense nuclear matter, suggesting that the nucleons in the stars' interior form Cooper pairs and exhibit macroscopic quantum behaviour. In this talk, I will focus on the superconducting protons in the outer core, which are expected to show type-II properties....
The discovery of pulsations in ultra luminous X-ray sources (ULXs) revealed a new class of neutron stars. These possibly strongly magnetized stars accrete matter at prodigious (super-Eddington) rates and are subject to very high spin-up torques. Other classes of sources such as the Z sources (e.g., Sco X-1) have accretion disks radiating at nearly Eddington luminosity. Recent computing...
The thermodynamical potential as well as all thermodynamical quantities of a neutral boson gas bearing a magnetic moment in presence of a constant magnetic field are calculated in the low temperature limit. The Bose Einstein Condensation (BEC) is studied. For the weak field regime the gas shows a usual BEC whereas for the strong field regime a diffuse BEC appears. This diffuse BEC is...
Slowly rotating magnetized white dwarfs are studied within the framework of general relativity using Harte's formalism. Matter inside magnetized white dwarfs is described by an equation of state of particles under the action of a constant magnetic field, which breaks the SO(3) symmetry and introduces a splitting of the pressure into one parallel and other perpendicular to the magnetic field....
A phenomenological model which has had some sucess in explaining polarization phenomena and left-right asymmetry in inclusive proton-protons reactions involving photons. In particular,the reactions (a) gamma+p ->H+X;(b) gamma+p(->) -> pi+X and (c)p(->)+p-> gamma + X are considered where gamma=resolved photon and hyperon H=Lambda, Sigma, etc. Predictions for hyperon polarization in (a)and the...
The discoveries of the last three decades on deep sea and deep crust of planet Earth show that life can thrive in many places where solar radiation does not reach, using chemosynthesis instead of photosynthesis for primary production. Underground life is relatively well protected from hazardous ionizing cosmic radiation, so above mentioned discoveries reopen the habitability budget of the...
The potential of organic vesicles to harbor a population of an elemental chemical replicator in an extremely hostile UV environment is considered. In this case, the vesicle acts as an effective shield against the harmful effects of the UV radiation, whereas in the external medium, the molecules of the replicator are readily destroyed. According to our results, replicators in the vesicle only...
Sensitivities studies of color reconnection (CR) effects in top-antitop underlying events (UE) were performed for the fully leptonic and fully hadronic final states (FLFS and FHFS respectively) events. A new Tune for the new CR [1] reconnection model parameters implemented in PYTHIA [2] is tested based on Rivet [3] routines. Effects of CR were studied based on a new Rivet Analysis. Differences...
We explore systematically a new class of two-phase equations of state (EoS) for hybrid stars that is characterized by three main features : (1) stiffening of the nuclear EoS at supersaturation densities due to quark exchange effects (Pauli blocking) between hadrons, modelled by an excluded volume correction, (2) stiffening of the quark matter EoS at high densities due to multiquark...
We have collected and analyzed the complete archive of XMM-Newton (116), Chandra (151), and RXTE\/ (952) observations of the Small Magellanic Cloud (SMC), spanning 1997-2014. The resulting observational library provides a comprehensive view of the physical, temporal and statistical properties of the SMC pulsar population across the luminosity range of $L_X=...
In reference [1] a simple SU(3) gauge model including a Yukawa interaction with a scalar field, was considered. Its two loop effective potential for the scalar field, predicted a 126 GeV Higgs mass after the minimum of the potential was fixed at a mean scalar field giving a 173 GeV Top quark mass. A high value of the strong coupling value was required to obtain these results ($\alpha$ close...
We study the consequences of Casimir effect on the evolution of the brane world scenario with both warped and compact extra dimensions.
High brightness beam manipulation is an important topic in several applications of accelerators in medicine and other industrial and scientific areas. The key question is dealing with the emittance control through the whole accelerator system including the tools for focusing and bending. In recent years, particular efforts are paid to improve the quality of the beams by means of nanostructures...
In this contribution, we explore the behavior of charged-particle pseudorapidity density in heavy ion collisions taking as a basis the results reported by the ALICE collaboration with regard to a more large range of the impact parameter. The main objective is to analyze the connexion of the total number of charged particles produced in Pb–Pb collisions in comparison with the p-p collisions...
I will present some generalities about the time dependence of the Newton and cosmological 'constants' and discuss some of the cosmological consequences of introducing such dependence in general relativity.
Effects of noncommutativity of the phase space deformations are presented on Schwarzschild, Kerr black holes making a comparative study of their thermodynamicals properties. In the case of the cosmological constant, this idea has been previously studied in FRW cosmology where the noncommutativity provides a simple mechanism that can explain the origin of the comsological constant.
RX J1856.5-3754 ia a radio-quiet Isolated Neutron Stars (INSs) discovered in the soft X-rays through their purely thermal surface emission. Owing to its large inferred magnetic fields ($B\approx 10^{13}$ G), radiation from this source is expected to be substantially polarised, independently on the mechanism actually responsible for the thermal emission. A large observed polarisation degree...
A large class of bound-state solutions of a modified D-dimensional Klein-Gordon equation, featuring an additional vector interaction nonminimally coupled, is obtained from the nonrelativistic bound-state solutions of the one-dimensional generalized Morse potential via Langer transformation. Some results found in the literature, including the so-called Klein-Gordon oscillator, are obtained as...
In this contribution the production of gravitons via two photon fusion process is considered using the scale of the gravitational interactions around a few TeV. We focus on the expected energy of the International Linear Collider (ILC) with a center of mass energy at TeV scale. The number of events is predicted and the background from Standard Model is analyzed.
We propose a thermodynamic framework to obtain exact solutions of Einstein’s field equations for spherically symmetric spacetimes based on identifying Komar energy as thermodynamical energy and gravitational entropy as proportional to horizon area. The approach is justified by considering gravitational path integrals with finite boundaries and allows us to understand at which extent the...
The Fock-Tani formalism is a first principle method to obtain effective interactions from microscopic Hamiltonians. Originally derived for meson-meson or baryon-baryon scatttering, we present the corresponding equations for meson-baryon scattering and annihilation for a KN interaction.
One of the surprises of the results coming from the LHC was the correlation between charge particle multiplicity and the mean transversal momentum. At first, these results in Pb-Pb collisions were attributed to the collective hydrodynamical properties of the Pb-Pb system. Then, for some observables, it was not surprising that the same behavior came out of p-Pb experiments, as similar...
Models beyond the Standard Model with extra scalars have been highly motivated by the recent discovery of a Higgs boson. The Two Higgs Doublet Model Type III considers the most general case for the scalar potential, allowing mixing between neutral CP-even and CP-odd scalar fields. This work presents the results of the study on the t → cγ, t→ c Z, and t → c gluon decays at one loop level if...
General relativity offers an impressive description of gravity at the classical level. A key ingredient in its construction is local Lorentz invariance, which insures rotation and boost symmetry in a freely falling frame. However, achieving a consistent unification of gravity with quantum physics may require modifications of the foundations of general relativity. These modifications could...
The cluster formation is not a fully understanding process until today, several theoretical models are emerging with the intention of explaining the phenomenon and reproducing the experimental data. The main objective of this work is to conceive a new method based on first physical principles independent on experimental parameters. Taking as scenario of this work the nuclear reactions p-197Au...
In an effort to unify gravity with the other three fundamental forces, many theoretical models have predicted the existence of non-Newtonian gravitational forces at sub-millimeter range or closer. The current constraints at micrometer range were mostly derived from the precision measurements of the Casimir force. However, the reliability of this method depends on the theoretical calculation of...
I will review the ongoing tests for the nature of dark energy along redshift. Observations of Type Ia supernovae at redshift z beyond 1 test both the density of dark energy and the evolution of the equation of state. Is there evidence of an evolution or are we having a constant dark energy behaviour such as the one expected if dark energy is the cosmological constant? I will discuss the...
