Supergravity and string based models typically contain hidden sectors. We discuss the physics of hidden sectors and how they affect analyses of phenomena related to particles and cosmology
It is known that there is huge hierarchy among the masses of quarks and leptons, and the lepton mixing is drastically different from quark mixing. The origin of fermion masses and flavor mixing is a longstanding puzzle of SM. Modular symmetry is a promising approach to address the flavor puzzle. This approach can overcome the drawbacks of traditional flavor symmetry, and it allows to explain...
Common lore suggests that effects of quantum gravity are difficult to unravel. The Planck scale is in fact about 14 orders of magnitude above the highest energy reached on Earth, namely at the Large Hadron Collider. In this talk, I will show that the quantum gravity cut-off can decrease in certain situations thus making quantum gravity effects accessible at energies lower than the Planck...
The latest SUSY/BSM related searches and hints/anomalies in CMS
An overview of anomalies identified in ATLAS searches for new physics phenomena will be presented.
The LHCb experiment conducts a wide programme of measurements which indirectly probe physics beyond the standard model. Rare decays of beauty and charm quarks which proceed via flavour-changing neutral currents are particularly sensitive to new physics at the TeV scale and above. This talk will describe recent LHCb analyses of rare B and D meson decays to muons that have particular sensitivity...
In this talk, we focus on the TeV scale B−L extension of the Minimal Supersymmetric Standard Model (BLSSM), which naturally incorporates a seesaw mechanism for generating light neutrino masses. Our emphasis will be on exploring the various phenomenological implications of this class of models.
The large top quark samples collected with the ATLAS experiment at the LHC have yielded measurements of the production cross section of unprecedented precision and in new kinematic regimes. They have also enabled new measurements of top quark properties that were previously inaccessible, enabled the observation of many rare top quark production processes predicted by the Standard Model and...
Neutrinos having a non-zero mass is our first laboratory evidence for New Physics. Yet the absolute mass scale remains unknown. Cosmology plays a fundamental role, as it sets the world-leading constraint and, in the near future, it should measure the exact value.
However, any cosmology inference is indirect. So, what are we really measuring with current cosmological data?
In this talk, I...
I will present the most minimal realistic SU(5) unification model to date. The minimality of the field content of the model dictates that the neutrinos are purely Majorana fermions while one of the three neutrinos is a massless particle. The model also connects the neutrino mass generation mechanism with the experimentally observed mass disparity between the down-type quarks and charged...
We investigate the doublet variant left-right symmetric model (LRSM) using the cosmic microwave background (CMB). The masses of neutrinos and other fermions are determined solely by their interactions with the Higgs bidoublet in this model. Light neutrinos, as Dirac particles, introduce additional relativistic degrees of freedom that interact in the early universe, particularly in the right...
Left-Right (LR) theories are one of the successful beyond Standard Model (SM) frameworks that explain the origin of small neutrino masses and low-energy weak parity violation. However, the conventional LR theory faces a challenge due to the presence of flavor changing neutral currents (FCNCs). To address this, we have studied an Alternative LR model (ALRM), which avoids FCNC constraints. Our...
I will discuss some theoretical and phenomenological implications of a string theory-inspired, cosmological phase of kination, dominated by the kinetic energy of a rapidly rolling scalar. In the first part of the talk, I will argue how such a kination epoch can naturally arise in string compactifications after inflation, focusing on the case where it is driven by the volume modulus. I will...
This talk covers recent measurements on top-pair production, and top-pair in association with additional boson or quarks, using the data collected by the CMS detector. Differential measurements of tt+X processes under the EFT framework are also presented.
Axion-like particles (ALPs) decaying before the time of recombination can have strong implications in a range of cosmological and astrophysical observations. In this talk I present a global analysis of a model of decaying ALP, focusing specifically on their coupling to photons. Exploiting the multidisciplinary nature of the GAMBIT framework, we combine state-of-the-art calculations of the...
In our study, we explore the influence of catalysis on the vacuum decay within the framework of type IIB string theory. This decay process involves the creation of a bubble that combines with an impurity, effectively acting as a catalyst. Although we show the 1-loop analysis at first, to calculate the life-time more accurately, we take use of variational perturbation method and go beyond the...
The top-quark pair production in association with a W boson is an important background to processes like t¯tH or 4-top production. Due to higher order electroweak corrections, the process is difficult to model. In consequence, a difference between the measured and the predicted value for σ(t¯tW) has been observed in previous analyses. To improve our understanding of this process, a new...
In this work, we present a comprehensive study of the phase diagram of supersymmetric QCD with $N_{f}=N_{c}+1$ flavors perturbed by Anomaly Mediated Supersymmetry Breaking (AMSB). We extend the analysis done before for the s-confining ASQCD theories in three different directions. Previously it was assumed that it is possible to ignore terms proportional to $m_{3/2}^{2}$ when $m_{3/2}$ is...
Many different theories beyond the Standard Model (SM) predict that new physics will manifest itself by decaying into final states involving leptons. Leptoquarks are predicted by many new physics theories to describe the similarities between the lepton and quark sectors of the SM. Right-handed Ws and heavy-neutrinos are also predicted by many extensions of the SM in the gauge sector, and...
We generalise the Missing Partner Mechanism to split the electron-like states from the coloured ones of vector-like $SU(5)$ 10-plets. Together with the extra light weak doublets from the Double Missing Partner Mechanism (DMPM), this realises gauge coupling unification in the presence of a light weak triplet and colour octet - the characteristic light relics from the adjoint in $SU(5)$ GUT...
A cosmological network of axion strings in our Universe today may leave its imprint on the polarization pattern of the cosmic microwave background radiation through the phenomenon of axion-string-induced birefringence. I will explain how this signal arises, discuss how it depends on the properties of the string network and the axion-photon coupling, describe how existing measurements of...
We present the full Lagrangian and local supersymmetry transformation rules for the gauged D=4, N=4 (half-maximal) supergravity coupled to an arbitrary number of vector multiplets. Using the embedding tensor formulation, the final results are universal and valid in an arbitrary symplectic frame. We also derive the conditions satisfied by the critical points of the scalar potential and we...
In the first part of this talk I will describe a Left-Right symmetric model that provides an explanation for the mass hierarchy of the charged fermions within the framework of the Standard Model. This explanation is achieved through the utilization of both tree-level and radiative seesaw mechanisms. In this model, the tiny masses of the light active neutrinos are generated via a three-loop...
Early Dark Energy (EDE) is a promising model to resolve the Hubble Tension, that, informed by Cosmic Microwave Background data, features a generalization of the potential energy usually associated with axion-like particles. We develop realizations of EDE in type IIB string theory with the EDE field identified as either a $C_4$ or $C_2$ axion and
with full closed string moduli stabilization...
In this talk, I will discuss the latest efforts to constrain the mass of the ultra-light dark matter models, focusing on the current bounds of the fuzzy dark matter (FDM) model. I will show how we can use the different predictions of this model and different astrophysical systems to put the strongest bounds to date on the mass of this ultra-light axion, showing also the incompatibilities that...
In this talk, within the bottom-up approach to holography, I will consider a class of six-dimensional gravity models and solutions that can be interpreted in terms of dual five-dimensional conformal field theories deformed by a single scalar operator. The scaling dimension of this operator is treated as a free parameter. One dimension in the geometry is compactified on a shrinking circle,...
The "minimal" potentially realistic non-supersymmetric $\mathrm{SO}(10)$ GUT model has a scalar sector consisting of representations $45+126+10$. The $45+126$ part breaks $\mathrm{SO}(10)$ to the Standard Model symmetry, while $126+10$ should enable a realistic Yukawa sector. This model is expected to facilitate an unusually robust proton decay prediction, but its analysis is impeded by...
A vector boson $W_{1}$ with the quantum numbers $\left(3,1\right)$ under the electroweak group $SU\left(2\right)_{L}\times U(1)_{Y}$ could in principle couple
with the Higgs field via the renormalizable term $W_{1}^{\mu*}H D_{\mu}H$. This interaction is known to affect the $T$ parameter and, in so doing, it could potentially explain the 2022 CDF measurement of the W-boson mass.
As it is...
Coloured sparticles are expected to be produced copiously at the LHC. As no squarks or gluinos have been found so far, their lower mass limits are in the TeV range, and they would therefore always be produced close to their production threshold. In this kinematical limit, potentially dangerous large logarithms can be summed systematically to all orders by means of threshold resummation...
RG-induced moduli stabilisation was recently proposed as a new mechanism that adapts to string theory a perturbative method for stabilising moduli without leaving the domain of perturbative control and without the inclusion of non-perturbative effects. In this talk, we briefly revise the necessary ingredients in the construction of this mechanism. In addition, we examine the cosmological...
In this work, we construct promising model building routes towards SO(10) GUT inflation. We consider a supersymmetric framework within which the so-called doublet-triplet splitting problem is solved without introducing fine-tuning. Additionally, realistic fermion masses and mixings, gauge coupling unification, and cosmic inflation are incorporated by utilizing superfields with representations...
Dark matter may exist as an ultralight bosonic particle, leading to the formation of an ever-present field that could interact with us via a new long-range fifth force. Recently, quantum sensing techniques have been shown to be promising avenues with which to detect such a dark matter candidate. However, these studies did not entirely capture the stochastic nature of the field, which is...
This talk presents combinations of orthogonal search channels, which improve the sensitivity to supersymmetric models by considering multiple final states simultaneously.
We study the inflection point inflation generated by polynomial superpotential and canonical K\"ahler potential under the supergravity framework, where only one chiral superfield is needed. We find the special form of the scalar potential limits the possible Hubble value up to $\mathcal{O}(10^{10}) \, \textrm{GeV}$ and the inflaton mass to $\mathcal{O}(10^{11}) \, \textrm{GeV}$. We obtained...
We revisit the Affleck-Dine leptogenesis via the $L H_u$ flat direction with a light slepton field. Although the light slepton field is favored in low-energy SUSY phenomenologies, such as the muon $g-2$ anomaly and bino-slepton coannihilation, it may cause a problem in the Affleck-Dine leptogenesis: it may create an unwanted charge-breaking vacuum in the Affleck-Dine field potential so that...
In this talk, I delve into the potential of multi-scalar interactions within the $\kappa$-framework as effective discriminators of BSM physics at current and upcoming colliders. By analysing the existing and projected collider constraints on these coupling modifiers, we can identify deviations from the Standard Model expectations, which serve as signposts for BSM discoveries. Building upon...
A Strong First-Order Electroweak Phase Transition (SFOEWPT) is a necessary ingredient for Electroweak Baryogenesis (EWBG) to explain the observed Baryon asymmetry of the Universe. Supersymmetric models with singlet extensions can easily accommodate single or multi-step first-order phase transitions (FOPT). In this work, we examine the dynamics of an SFOEWPT and the possibility of EWBG by...
I will present theoretical calculations of total cross sections and top-quark transverse-momentum and rapidity distributions in the associated production of a top-antitop pair with a photon (t t~ γ production) in the SM and SMEFT.
The theory predictions include complete QCD and electroweak corrections at NLO as well as soft-gluon corrections at approximate NNLO. Implications for SM...
Using the $\kappa$ framework, the constraints on the quartic interactions of Higgs with gauge bosons give a qualitative picture of consistency with the SM when the statistical yield is low. However, increasing statistics demand a more theoretically consistent framework to limit such couplings. Adopting the Higgs Effective Field Theory (HEFT) framework, we calculate the radiative corrections to...
A brief review of model building in F-theory will be presented. Next, some recent insights into the flux induced superpotentials of the moduli fields will be discussed.
In this talk I will consider the string theory axiverse in type IIB Calabi-Yau orientifold compactifications, and focus on the computation of axion photon couplings and hierarchies that arise in the many axion limit — i.e. at large values of $h^{1,1}$. In particular, I will discuss two distinct phenomena that hierarchically suppress axion photon interactions when the QED divisor is small: the...
Supersymmetry (with R-parity conservation) provides a natural dark matter candidate. In models with gravity mediated supersymmetry breaking, the discovery of the Higgs boson with mass 125 GeV and the lack of discovery of supersymmetric particles at the LHC heavily constrains this framework for dark matter. The current status will be reviewed. Supergravity may also play an important role in...
The nature of dark matter is one of the most important questions in fundamental physics. The talk will cover potential explanations, related experiments together with their latest results and potential for the future.
Cosmological relaxation of the electroweak scale via Higgs-axion interplay, named as relaxion mechanism, provides a dynamical solution to the Higgs mass hierarchy. I will review the status of the proposal and
will show that the relaxion can naturally explain the observed dark matter density in the universe.
In addition to the supersymmetric vacua in 10 dimensions, heterotic-string theory gives rise to non-supersymmetric vacua that are in general contain physical tachyons in compactifications to 4 dimensions, which can be projected out by the GSO projections, and produce string amplitudes that are finite at one—loop. Over the past few years, in collaboration with Viktor Matyas and Ben Percival, we...
Modular transformations of string theory are shown to play a crucial role as discrete flavor symmetries of the Standard Model. They include CP transformations and provide a unification of CP and traditional flavor symmetries within the framework of the eclectic flavor scheme. The unified flavor group is non-universal in moduli space and exhibits the phenomenon of "Local Flavor Unification"...
Determination of the nature of dark matter is one of the most fundamental problems of particle physics and cosmology. This talk presents recent searches for dark matter particles from the CMS experiment at the Large Hadron Collider. The results are obtained from the proton-proton collision data at the center of mass energy of 13 TeV collected during the LHC Run 2.
I will argue that coloured gravitational instantons compromise the standard axion solution to the strong CP problem and propose a companion axion model as the solution, that necessarily contains two axions. I will discuss some phenomenological and cosmological consequences of this model.
Based on - 2108.05549, 2109.12920, 2110.11014
This talk reviews recent measurements of multiboson production using CMS data. Inclusive and differential cross sections are measured using several kinematic observables.
The latest results from searches for electroweak production of SUSY particles with the CMS experiment will be presented. The analyses are based on the full dataset of pp collisions recorded at sqrt(s) = 13 TeV during the LHC Run 2. Searches are performed in multiple final states and the combination of those searches will be also discussed.
Dimensionless fundamental constants can vary as a function of time if an ultralight field couples to the standard model. Using data on strontium, ytterbium and caesium atomic-clock transitions collected by the National Physical Laboratory in the UK, fine-structure constant and electron-to-proton mass ratio variations have been measured for about two weeks. These data enable the extraction of...
In the pursuit of physics beyond the Standard Model, a promising path is the study of exclusive B-meson decays caused by the transition b→sℓ+ℓ−. A key observable in such decays is the ratio $R_K$, which measures electron-muon universality in B→Kμ+μ−/e+e-. At first sight, the recent LHCb measurement of RK ~ 1 may seem to largely constrain deviations from universality in these decays. However,...
CP-violating contributions to Higgs--fermion couplings are absent in the standard model of particle physics (SM) but are motivated by models of electroweak baryogenesis. In this talk, I will present results of a study of the constraints on these couplings from a combination of LHC data and experimental bounds on the electron, neutron, and mercury electric dipole moments (EDMs). While previous...
I will discuss about the halo-independent bounds on the WIMP-nucleon couplings of the non-relativistic effective Hamiltonian that drives the scattering off nuclei of a WIMP of spin 1/2. We will see that for most of the couplings the degree of relaxation of the halo-independent bounds compared to those obtained assuming the Standard Halo Model is with few exceptions relatively moderate in the...
Accommodating differing signs of the supersymmetric contributions to $g-2$ values of muon and electron can be difficult in the Minimal Supersymmetric Standard Model (MSSM) in the context of Fermilab muon ${(g-2)}_\mu$ data and electron ${(g-2)}_e$ result as obtained from the fine structure constant ($\alpha$) measurement through ${}^{133}{\rm Cs}$ matter-wave nterferometry. The latter would...
At the proposed future Large Hadron-Electron Collider (LHeC), the coupling between the Higgs boson (H) and the massive gauge bosons (V = W, Z) of weak interaction can be investigated through the single Higgs boson production. In this presentation, I will focus on the potential of the collider to determine constraints on the new physics parameters associated with the most general structure...
Numerous studies have led to upper limits on the dark matter annihilation cross-section assuming only single exclusive annihilation channels. We consider a more realistic situation and present a study taking into account the complete annihilation pattern within a given particle physics model. This allows us to study the impact on the derived upper limits on the dark matter annihilation...
The positivity of the scattering amplitude is a necessary condition for a low-energy effective field theory (EFT) to be UV complete. The gravitational positivity bound provides quantitative "swampland" constraints for low-energy EFTs to be UV complete within quantum gravity. The condition can give significant constraint on a feebly interacting particle model and its UV completion. In this...
The lack of positive signals from supersymmetry searches at the LHC has pushed most of supersymmetric particles to very heavy masses. The notable exception is the electroweak sector of the MSSM which, due to their mixings and complex parameter structure, could still survive at fairly low masses. In this talk I will present a global study of the electroweak minimal supersymmetry extension of...
Abstract: The primary ingredient for studying the phases of a quantum field theory is the effective action. Though obtaining an exact form is beyond the scope of the existing techniques, approximate expressions using perturbative methods which to the leading order involve computation of one-loop determinants are available. In this talk which is based on our papers [1] and [2], I will describe...
We investigate the right handed sneutrino effect, in the framework of the $B−L$ extension of Minimal Supersymmetric Standard Model with Inverse Seesaw, on $b \to c l \bar\nu_l$ decays anomalies which has been recently measured in the lepton-universality ratios $\mathcal{R(D^{(*)})}=\mathcal{BR(B \to D^{(*)}\tau \bar\nu_{\tau})/BR(B \to D^{(*)}l \bar\nu_l)}$ ($l=e$ or $\mu$). Taking into...
Searches for new physics (NP) at particle colliders typically involve multi-variate analysis of kinematic distributions of final state particles produced in a decay o fa hypothetical NP resonance. Since the pair-production cross-sections mediated by such resonances are strongly suppressed by the NP scale, this analysis becomes less relevant for
NP searches for masses of the BSM resonance...
The event rates and kinematics of Higgs boson production and decay processes at the LHC are sensitive probes of possible new phenomena beyond the Standard Model (BSM). This talk presents precise measurements of Higgs boson production and decay rates, obtained using the full Run 2 and partial Run 3 pp collision dataset collected by the ATLAS experiment at 13 TeV and 13.6 TeV. These include...
We study the production of Dark Matter (DM) in a minimal freeze-in model during inflationary reheating. We analyze the case where a heavier parent particle decays into DM and a Standard Model fermion in two reheating scenarios: bosonic reheating (BR) and fermionic reheating (FR). Firstly, we show that for low reheating temperatures, BR and FR scenarios predict different lifetimes and masses...
The lack of evidence for new physics in the LHC data puts stringent constraints on supersymmetric theories. However, searches for supersymmetric particles at the LHC are made channel-by-channel in specific final states, and the results are typically presented in the context of simplified models. It is therefore important to reinterpret the results of these searches by confronting them to full...
Primordial Black Holes (PBHs) may form in the early universe, from the gravitational collapse of large density perturbations, generated by large quantum fluctuations during inflation. Since PBHs form from rare over-densities, their abundance is sensitive to the tail of the primordial probability distribution function (PDF) of the perturbations. It is therefore important to calculate the full...
In this talk we discuss recent results from the CMS experiment on Higgs boson coupling and cross section measurements. A variety of different production modes and final states are discussed. We also present differential cross section measurements and constraints on anomalous Higgs boson couplings.
After a brief introduction to phase transitions and explain why they are worth studying, I will examine those in the minimal extension of the SM using a real singlet scalar field. The uniqueness of our study lies in the identification and detailed analysis of a parameter space region where a first-order phase transition with relativistic expanding bubbles can occur. This particular region is...
Grand Unified Theories (GUTs) aim to unify all three fundamental interactions including electromagnetic, strong and weak interactions. A well-known phenomenological prediction of GUTs is proton decay, which sets a strong constraint to GUTs due to its null observation. On the other hand, masses and mixing of quarks and leptons are correlated since all fermions are arranged in the same...
Modified (the higher-derivative) supergravity models of cosmological inflation are introduced by extending the Starobinsky model of inflation to supergravity and including production of primordial black holes, in agreement with current precision measurements of the cosmic microwave background radiation. It leads to multi-field inflation, dark matter genesis as primordial black holes, and...
Particles that interact with the standard-model very weakly, or only gravitationally, may be created merely by the expansion of the universe. This mechanism may produce dark matter and be used to limit the properties of particles beyond the standard model.
High energy cosmic neutrinos are generated by the interactions of cosmic rays with matter & radiation, so their spectrum extends up to ZeV energies. The detection of cosmic neutrinos up to multi-PeV energies by the IceCube Neutrino Observatory at the South Pole has thus provided a novel laboratory for fundamental interactions, complementary to collider experiments. The measured cross-section &...
In 2005 I gave a talk at SUSY provocatively titled Neutr - the only Observed Ino (So Far). So far it still is. I will give a brief survey the progress made since 2005 and the prospects for further progress by future projects.
SModelS is a public tool for the fast reinterpretation of LHC searches for new physics on the basis of (mostly SUSY) simplified-model results. The latest version is v2.3, released in May 2023. In this talk, I will present some major novelties of the SModelS v2 series, in particular the database update with a large number of full-luminosity Run2 results, the treatment of signatures with...
Flavor has been traditionally seen as a problem for supersymmetric theories, "the flavor problem". Still, the Standard Model is not immune to this problem, also Yukawa couplings should be naturally O(1).
Flavor symmetries are used to explain the structure of Yukawa couplings and, simultaneously, of soft-breaking couplings in supersymmetric theories. In this scenario, SUSY can help to...
The neutrino oscillation studies of the last decades have brought neutrinos to the center of particle physics, leaving an important legacy for new physics. I will briefly review the status of precision neutrino results and comment on the insights they bring into the basic drawbacks of the Standard Model such as the origin of neutrino mass, the flavour problem and dark matter.
I present a general formalism for multiple moduli and their associated modular symmetries, then apply it to examples based on finite modular symmetries, leading to viable and predictive modular flavour models.
More than twenty years ago a paradigm emerged according to which supersymmetric theories with compact extra dimensions and Scherk-Schwarz SUSY breaking could naturally provide a UV-insensitive Higgs mass $m_H$, and more generally a UV-insensitive Higgs potential $V_{1l}(\phi)$. Some warnings were originally raised on the validity of such an outcome, but the community soon came to an agreement...
Many extensions of the standard model predict new particles with long lifetimes or other properties that give rise to non-conventional signatures in the detector. This talk discusses new techniques to detect such signatures in the CMS detector, and presents recent results from such searches in CMS using the full Run 2 data set of the LHC.
Cosmologically plausible compactification scenarios typically require parametric separation between the cosmological and the compactification length scales.
When the higher-dimensional solution is in the semi-classical regime, the full quantum-corrected equations of motion are naturally expanded in the local values of various fields. In this talk, we will present constraints on AdS...
Obtaining genuine lower-dimensional theories from string theory remains a real challenge.
This can be done if the Kaluza-Klein energy scale can be made much larger than the cosmological constant.
In this talk, I review the situation for minimally supersymmetric models in type IIA string theory. There the separation of scales is achieved due to unbounded flux quanta that can be send to...
Searches are being carried out at the Large Hadron Collider (LHC) for the decay of the CP-odd scalar $(A^{0})$ in Two-Higgs-Doublet Models (2HDMs) with Natural Flavour Conservation (NFC) in the channel $A^{0}\rightarrow h^{0}Z^{*}$ (with $m_{h^{0}}=125 GeV$ and Z on-shell). In the absence of any signal, limits on the parameter space of $[tan\beta , cos(\beta -\alpha ), m_{A^{0}}]$in each 2HDM...
We consider Dark Matter (DM) production via the freeze-in mechanism with finite temperature corrections. Freeze-in is mostly sensitive to temperatures corresponding to the highest energy scale involved in the production reactions, contrary to the freeze-out paradigm, which occurs well within a non-relativistic regime. As a result, quantum and finite temperature corrections can significantly...
The neutralinos are well-motivated dark matter candidates and have been studied extensively. If the mass difference between the neutralino and chargino is relatively small, then they can be detected as, for example, disappearing charged tracks in collider experiments. The constraint on the chargino mass by those experiments strongly depends on the chargino lifetime, and hence, it is important...
The existence of AdS vacua in string theory with a parametric separation between the Hubble
scale and the Kaluza-Klein scale of the extra dimensions is an open question, and holography is a
promising tool to tackle this. I will discuss some remarkable holographic features
of the DGKT vacua, which are candidate AdS vacua with parametric scale separation.
Neutrino non-standard interactions (NSI) have been extensively explored in the context of dedicated neutrino experiments. However, the next generation of direct detection experiments is on course to observe a significant number of solar neutrino events, and the sensitivities of these experiments within the NSI landscape are yet to be determined. Due to their sensitivity to neutrino-nucleus and...
A new fundamental theory [1] unavoidably predicts supersymmetry, SO(N) grand unification, and a new description of all fundamental scalar bosons. As discussed in our previous papers [2-5] and many recent talks, this last feature in turn unavoidably predicts a dark matter WIMP which is consistent with all experimental and observational constraints, and which should be observable via direct...
The absence of supersymmetry in string theory usually leads to runaways, arising from nonvanishing dilaton tadpoles. The spacetime manifestation is a scalar potential, which might be a blessing in disguise for flux compactifications, even though it typically brings along singularities or instabilities.
In this talk, I will discuss a first-order formalism, already known in its most basic form...
We delve deeper into the potential composition of dark matter as stable scalar glueballs from a confining dark $SU(N)$ gauge theory, focusing on $N=\{3,4,5\}$. To predict the relic abundance of glueballs for the various gauge groups and scenarios of thermalization of the dark gluon gas, we employ a thermal effective theory that accounts for the strong-coupling dynamics in agreement with...
We present searches for additional Higgs bosons with data collected by the CMS experiment. Searches for additional Higgs bosons at high mass, such as those that can constrain the parameter space of the minimal supersymmetric standard model, will be discussed. We also cover searches for the 125 GeV Higgs boson decaying to a pair of light scalars.
Using interaction rates computed to second order in string perturbation theory, we pose a system of Boltzmann equations describing an ensemble of long open and closed strings in different regimes (which include high and low density of D-branes), for an arbitrary number of "effectively non-compact" directions, along which strings cannot wind. We find equilibrium distributions for all these...
Global non-topological solitons (Q-balls) exist when the potential of a charged scalar field grows slower than quadratically. At zero temperature, this requires attractive interactions. We first show that finite temperature effects can generate the necessary terms even in the absence of attractive interactions at zero temperature. As a result, non-topological solitons exist at finite...
The ATLAS collaboration has recently reported the results of a low-mass Higgs-boson search in the di-photon final state based on the full Run 2 data set. The largest "excess" is observed at 95.4 GeV with a significance of 1.7 $\sigma$. At exactly the same mass in the same channel CMS reported earlier an excess of 2.9 $\sigma$. Other excesses at about the same mass have been published by LEP in...
Based on the recent article [2023.02399], we discuss the LISA potential for finding evidence of New Physics from measurements of the Stochastic GW Background (SGWB). As a benchmark scenario, we study a version of the low-scale Majoron model equipped with lepton number symmetry and an inverse seesaw mechanism for neutrino mass generation. In particular, we discuss under which circumstances the...
We discuss Dark Matter (DM) in combination of $(g-2)_\mu$ in the MSSM. Six different scenarios according to the nature of the Next-to-lightest SUSY particle are identified. All relevant bounds from LHC searches, DM relic abundance and direct detection (DD) are taken into account. We show how collider searches and direct detection experiments can fully test these scenarios.
No-Scale SUGRA has attracted considerable interest as a framework for inflation as it provides a natural realisation of Starobinsky-like inflation models. Recently, it was shown that suitable modifications of the Kahler potential produce a kink on the inflaton scalar potential that generates an enhancement in the power spectrum, leading to the production of Gravitational Waves. In this talk,...
We present an updated and improved global fit analysis of current flavor and electroweak precision observables to derive bounds on unitarity deviations of the PMNS mixing matrix and the mixing of heavy neutrinos with the active flavours.
This new analysis is motivated by new and updated experimental results on key observables such as $V_{ud}$, the invisible decay width of the $Z$ boson and...
Cosmological phase transitions that are strongly first order are well motivated in physics beyond the standard model, for example as part of an electroweak baryogenesis solution to the matter anti-matter asymmetry, and could give rise to an observable gravitational wave spectra. Based on https://arxiv.org/abs/2305.02357 and https://arxiv.org/abs/2212.07559 I discuss various subtle issues in...
"Shi-Fuller mechanism" is known as one of the scenarios which can explain all dark matter by sterile neutrinos not conflicting with any other current observational constraints. We revisit the numerical calculation of final energy spectrum of sterile neutrinos for given initial lepton asymmetry in Shi-Fuller mechanism by properly incorporating the effects of neutrino oscillation in active...
Collider-testable low scale type I seesaw models for neutrino mass generation generically feature pseudo-Dirac heavy neutrinos, composed of two Majorana states with nearly degenerate masses. These pseudo-Dirac heavy neutral leptons (HNLs) can oscillate between interaction eigenstates that couple to leptons and antileptons, and thus generate oscillations between lepton number conserving (LNC)...
We revisit the model where bino coannihilates with slepton and higgsino is also at electroweak scale.
We update the LHC constraints and the dark matter direct detection constraints. Also, we consider the new physics contributions to muon g-2 and we find that there remains unexplored regions.
In supersymmetric theories the Higgs boson masses are derived quantities where higher-order corrections have to be included in order to match the measured Higgs mass value at the precision of current experiments. Closely related through the Higgs potential are the Higgs self-interactions. In addition, the measurement of the trilinear Higgs self-coupling provides the first step towards the...
Higher-order corrections involving (external) charginos and/or neutralinos require a renormalization of this sector. External particles should be renormalized on-shell (OS). Since the six chargino/neutralino masses are controlled by three mass parameters, many different OS renormalization schemes (RS) are possible. A given RS can be well suited to yield "stable" and "well behaved" higher-order...
The aim of this paper is to highlight the challenges and potential gains surrounding a coherent description of physics from the high-energy scales of inflation down to the lower energy scales probed in particle-physics experiments. As an example, we revisit the way inflation can be realised within an effective Minimal Supersymmetric Standard Model (eMSSM), in which the LLe and udd flat...
We discuss a dark photon model with successive symmetry breaking $\mathrm{SU(2)_D}$ $\to$ $\mathrm{U(1)_D}$ $\to$ $\mathbb{Z}_2$ in the dark sector. Various dark topological defects appear, such as monopoles, dyons, strings and beads. They are shown to induce QED electromagnetic fields through kinetic and magnetic mixing between $\mathrm{U(1)_{QED}}$ and $\mathrm{U(1)_D}$. In particular, dark...
Higher symmetries in quantum field theory are novel concepts of symmetry that involve extended operators such as Wilson lines in gauge theory. We briefly review this formalism and then discuss recent applications to particle physics, including an organizing principle for unification models and instanton effects. Finally, we discuss how higher symmetry violation can lead to simple models of...
String theory provides a powerful framework for generating and studying strongly coupled quantum field theories, including so-called “non-Lagrangian” theories that have no weak coupling limit. In this talk, I will summarize recent developments regarding dual descriptions of a class of strongly interacting 4d N=2 superconformal field theories that arise from string theory. I will highlight how...
I will argue on the possibility that the smallness of some physical parameters signals a universe at a large distance corner in the string landscape of vacua. Such parameters can be the scales of dark energy and supersymmetry breaking, which should then be tied to a large `dark' dimension at the micron scale. I will discuss the theoretical framework and some of its main physical implications.
Dark Matter constitutes more that 80% of the total amount of matter in the Universe, yet almost nothing is known about its nature. A powerful investigation technique is that of searching for the products of annihilations of Dark Matter particles in the galactic halo (and beyond), on top of the ordinary cosmic rays.
If a few anomalies still exist (notably the GeV GC gamma-ray excess), most...
The Next-to-Minimal Supersymmetric Extension of the Standard Model (NMSSM) is a well motivated supersymmetric extension beyond the minimal version, the MSSM. It solves the mu-problem and relaxes somewhat the tension in achieving the measured value of the Standard Model (SM)-like Higgs boson mass value. In this talk, I will address precision predictions for the NMSSM Higgs sector as well as the...
The Weak Gravity Conjecture proposes that in any effective theory that can be consistently coupled to gravity, gravity must be the weakest force. I will review recent work on understanding this idea in anti-de Sitter space using holography. In particular, I will show that a certain formulation of the Weak Gravity Conjecture can be mapped to convexity properties of operators which are charged...
By studying M-theory on singular non-compact special holonomy spaces X we demonstrate, via a process of cutting and gluing of singularities that extend to the boundary of X, the appearance of 0-form, 1-form and 2-group symmetries in the resulting supersymmetric quantum field theory. We study the fate of these symmetries when these spaces become compact by employing sophisticated gluing...
Genetic Algorithms (GAs) are some of the most simple and effective search methods. In this talk I will demonstrate and review their effectiveness in various applications in BSM physics, including string searches, cosmology and phenomenological searches. For the latter I will emphasize the untapped potential for combining GAs with other search methods.
I will discuss the possibility of non-minimal flavour violation the supersymmetric theories. Focussing on the sector of squarks, after a general introduction, I will review recent results covering both the implementation within grand unified theories and TeV-scale phenomenology.
Ten years of LHC Higgs data indicate that the properties of the observed Higgs boson are consistent (within the precision of the experimental data) with the predictions of the Standard Model (SM). Thus, any viable supersymmetric extension of the SM must incorporate a SM-like Higgs boson. This can be achieved either via the decoupling limit (where all additional Higgs scalars have masses...
I discuss computer tools for SUSY collider phenomenology, recent developments and applications.
We discuss the interplay of First Order Electroweak Phase Transitions (FOEWPT), Triple Higgs Couplings (THCs) and Gravitational Waves (GWs) in the 2 Higgs Doublet Model (2HDM). We identify six thermal histories in the 2HDM, out of which one leads to a FOEWPT. We discuss the implications for GWs and the measurement of THCs at the HL-LHC and future $e^+e^-$ colliders, such as the ILC.
The recent observation of $^4$He favors a large lepton asymmetry at the big bang nucleosynthesis. If Q-balls with a lepton charge decay after the electroweak phase transition, such a large lepton asymmetry can be generated without producing too large baryon asymmetry. In this scenario, Q-balls dominate the universe before the decay and induce the sharp transition from the early...
Phenomenological implications of the simplest multi-Higgs extensions of the Standard Model constrained by additional global horizontal flavour symmetries will be overviewed. A particular focus would be given to their basic implications for Higgs and flavour physics as well as for possible detection of primordial gravitational waves.
I will discuss a tri-hypercharge (TH) extension of the Standard Model (SM) in which a separate gauged weak hypercharge is associated with each fermion family, avoiding the family repetition of the SM. If the SM Higgs doublet only carries third family hypercharge, then only third family renormalisable Yukawa couplings are allowed, explaining the hierarchical heaviness of their masses. I will...
Under supersymmetry (SUSY) models with low electroweak naturalness (natSUSY), which have been suggested to be the most likely version of SUSY to emerge from the string landscape, we examine the viabilities of future search for the heavy SUSY Higgs bosons H, A, H^\pm through various their decay signatures in LHC. The traditional H, A -> tautau, as well as H^\pm -> tau+nu, t+b, with a spectator...
MicroBooNE is an 85-tonne active mass liquid argon time projection chamber (LArTPC) at Fermilab. With an excellent calorimetric, spatial and energy resolution, the detector was exposed to two neutrino beams between 2015 and 2020. These characteristics make MicroBooNE a powerful detector not just to explore neutrino physics, but also for Beyond the Standard Model (BSM) physics. Recently,...
The sound shell source from a cosmic phase transition is a compelling explanation for the stochastic gravitational wave background recently seen by various PTA collaborations. I discuss motivations for such a phase transition as well as comparing the sound shell model using the full velocity profile, as opposed to the broken power law that results from using the rms fluid velocity. Finally I...
We consider a minimal non-supersymmetric SO(10) Grand Unified Theory (GUT) model that can reproduce the observed fermionic masses and mixing parameters of the Standard Model. We calculate the scales of spontaneous symmetry breaking from the GUT to the Standard Model gauge group using two-loop renormalisation group equations. This procedure determines the proton decay rate and the scale of...
The proposed LUXE experiment (LASER Und XFEL Experiment) at DESY, Hamburg, using the electron beam from the European XFEL, aims to probe QED in the non-perturbative regime created in collisions between high-intensity laser pulses and high-energy electron or photon beams. This setup also provides a unique opportunity to probe physics beyond the standard model. In this talk we show that by...
We suggest a new class of models "a Fermionic Portal Vector Dark Matter" (FPVDM) which extends the Standard Model (SM) with a minimal non-Abelian $SU(2)_D$ dark gauge sector. Since the mixing between the SM and dark scalars is negligibly small, the main connection between two sectors is established on the mixing between a Vector-Like (VL) fermionic doublet of $SU(2)_D$ dark group and their SM...
We discuss triple Higgs couplings (THCs) in the 2 Higgs Doublet Model (2HDM). We show how the SM-like THC, but also BSM THCs involving BSM Higgs bosons can be tested in di-Higgs production at the HL-LHC. We emphasize the role of experimental uncertainties in the measurement of these processes.
The modular symmetry provides us with an intriguing solution to the flavor mixing puzzle. In the bottom-up approach to the modular-invariant flavor models, the modulus parameter $\tau$ is usually treated as a free parameter. Interestingly, there exist some special values of $\tau$ called stabilizers at which residual symmetries can be preserved after the spontaneous breaking of the global...
In the first part of the talk I will describe a Majoron-like extension of the Standard Model with an extra global U(1)X symmetry where neutrino masses are generated through an inverse seesaw mechanism at the 1-loop level. In contrast to the tree-level inverse seesaw, the framework contains dark matter candidates stabilized by a residual Z2 symmetry surviving spontaneous breaking of the U(1)X...
I will announce the next SUSY conference at the IFT in Madrid (Spain).
The detection of a heavy neutral CP-even Higgs boson of the $B-L$ Supersymmetric Standard Model (BLSSM), $h'$, with $m_{h'}\simeq 400~\text{GeV}$, at the Large Hadron Collider (LHC) for a center-of-mass energy of $\sqrt{s}=14~\text{TeV}$, is investigated. The following production and decay channels are considered: $gg\to h'\to{ZZ}\to4\ell$ and $gg\to h'\to{W^+W^-}\to2\ell+MET$ (with $MET$...
The Peccei-Quinn solution to the strong CP problem has a problematic aspect: it relies on a global U(1) symmetry which, although broken at low energy by the QCD anomaly, must be an extremely good symmetry of high-energy physics. This issue is known as the Peccei-Quinn quality problem. We propose a model where the Peccei-Quinn symmetry arises accidentally and is respected up to high-dimensional...
Recent results on inclusive W and Z boson productions obtained with the LHC Run 2 and run 3 proton collision data by the CMS collaboration are presented.
We study the prospect of simultaneous explanation of tiny neutrino masses, dark matter (DM), and the observed baryon asymmetry of the Universe in a $Z_3$-symmetric complex singlet scalar extended type-II seesaw model. The complex singlet scalar plays the role of DM. Analyzing the thermal history of the model, we identify the region of the parameter space that can generate a first-order...
The $E_6$ inspired extension of the minimal supersymmetric (SUSY) standard model (MSSM) with an extra $U(1)_{N}$ gauge symmetry, under which right-handed neutrinos have zero charge, involves exotic matter beyond the MSSM to ensure anomaly cancellation. In particular, there are three families of extra exotic quarks and several $SU(2)_W$-doublets that have the quantum numbers of the MSSM Higgs...
The NA62 experiment at CERN took data in 2016–2018 with the main goal of measuring the $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay. We report on the search for visible decays of exotic mediators from data taken in "beam-dump" mode with the NA62 experiment. The NA62 experiment can be run as a "beam-dump experiment" by removing the Kaon production target and moving the upstream collimators into a...
We present the latest results from the CMS experiment on searches for non-resonant di-Higgs production. In addition to an overview of the different channels that have been probed, we present constraints on the Higgs-boson self-coupling, the quartic coupling between two Higgs bosons and two vector bosons, as well as on anomalous interactions that affect the production of a pair of Higgs bosons....
The momentum distribution of the non-thermal dark matter produced during reheating is assumed to be the same as that at production, red-shifted at later times due to the expansion of the Universe. In this talk we show that, in such a scenario, DM self scatterings as well as scatterings with the SM bath via inflaton mediated processes are inevitable, which can have substantial impact on the...
Ultra-low mass primordial black holes (PBH) which may briefly dominate the energy density of the universe but completely evaporate before the big bang nucleosynthesis (BBN), may lead to interesting observable signatures. We propose a novel test of this scenario by detecting its characteristic doubly peaked gravitational wave (GW) spectrum in future GW observatories. Here the first-order...
The NA62 experiment at CERN collected the world's largest dataset of charged kaon decays in 2016-2018, leading to the first measurement of the branching ratio of the ultra-rare $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay, based on 20 candidates. In this talk the NA62 experiment reports recent results from analyses of $K^+ \rightarrow \pi^0 e^+ \nu \gamma$, $K^+ \rightarrow \pi^+ \mu^+ \mu^-$ and...
The lack of information before Big Bang Neucleosynthesis (BBN) allow us to assume the presence of a new species $\phi$ whose energy density redshifts as $a^{-(4+n)}$ where $n>0$ and $a$ is the scale factor. In this non-standard cosmological setup, we have considered $U(1)_{L_\mu-L_\tau} \otimes U(1)_X$ gauge extension of the Standard Model (SM) and studied different phases of the cosmological...
The latest results of searches for supersymmetry in photonic final states with the CMS experiment will be presented. The analyses are based on the full dataset of proton-proton collisions collected during the Run 2 of the LHC at a center-of-mass energy of 13 TeV. The results are interpreted in models including the stealth SUSY models and gauge mediated supersymmetry breaking models.
