Conveners
Parallel Session C: BSM
- Daniele Teresi (CERN)
Parallel Session C: BSM
- Andreas Trautner
Parallel Session C: Formal QFT
- Gauthier Durieux (CERN)
Parallel Session C: BSM
- Florian Goertz (Max-Planck-Institut fuer Kernphysik, Heidelberg, Germany)
Parallel Session C: BSM
- Robert Ziegler (KIT - Karlsruhe Institute of Technology (DE))
Parallel Session C: Formal QFT
- Michele Cicoli (Università di Bologna)
Gauge-Higgs Grand Unified Theories (GHGUT) embedded in a 5D spacetime unify the gauge symmetries of nature together with their breaking sector, at the same time providing a solution to the gauge hierarchy problem, the flavour puzzle, and the doublet-triplet splitting problem. In this talk, I will discuss the recently proposed 5D warped space GHGUT setup with an SU(6) bulk gauge group, where...
Gauge-Higgs Grand Unification Theories (GHGUTs) offer an interesting direction to solve some of the open questions of the SM, like the Hierarchy Problem and the Flavor Puzzle. Moreover, they allow for the unification of the gauge symmetries and their breaking sector. In this talk we discuss the evolution of coupling constants in GHGUTs, specifically a recently proposed minimal SU(6) warped...
The Standard Model (SM) fermion mass generation in the (Partially) Composite Higgs framework may suffer from problems due to, for example, reintroduction of new SM naturalness problems, generation of dangerous flavor changing neutral currents, instability of the Higgs vacuum, or challenging non-minimal model building. All these problems can be alleviated if these models have a large...
Simple scalar extensions of the Standard Model (SM) with a spontaneously broken $Z_2$ symmetry allow for a strongly first order electroweak phase transition, as sought in order to realize electroweak baryogenesis. To avoid the emergence of phenomenologically problematic domain walls one may encounter in this context, in 2112.12087 (A. Angelescu, F. Goertz, AT), a scalar singlet framework...
Experiments using proton beams at high luminosity colliders and fixed-target facilities provide impressive sensitivity to new light weakly coupled degrees of freedom. We revisit the production of dark vectors and scalars via proton bremsstrahlung for a range of beam energies, including those relevant for the proposed Forward Physics Facility (FPF) at the High Luminosity LHC. In addition, we...
We consider a simple extension of the Standard Model with a vector-like lepton and U(1)’ gauge symmetry motivated by the recent experimental anomalies in the muon g-2 and the W boson mass. After the U(1)’ symmetry is spontaneously broken, the mixings between the muon and the vector-like lepton and between the Z boson and the U(1)’ gauge boson arise. As a result, we obtain the desirable...
The existence of a mass gap between Standard Model and possible New Physics states has been confirmed experimentally. As a consequence, effective field theories are appropriate to search for signals beyond the Standard Model. We consider a non-linear realization of the electroweak symmetry breaking, where the Higgs is a singlet with independent couplings and the Standard Model fields are...
After developing a general criterion for deciding which neutrino mass models belong to the category of inverse seesaw models, we apply it to obtain the Dirac analogue of the canonical Majorana inverse seesaw model. We then generalize the inverse seesaw model and obtain a class of inverse seesaw mechanisms both for Majorana and Dirac neutrinos. We further show that many of the models have...
Many popular extensions of the SM require sizeable modifications to the trilinear Higgs boson coupling in order to accommodate a first-order electroweak (EW) phase transition. Cosmological first-order phase transitions can give rise to a primordial gravitational wave (GW) background which could be observable at future space-based GW detectors such as LISA. Focusing on the Yukawa type-II 2HDM...
Scattering amplitudes mediated by graviton exchange display IR singularities in the forward limit. This obstructs standard application of positivity bounds based on twice subtracted dispersion relations. Such divergences can be cancelled only if the UV limit of the scattering amplitude behaves in a specific way, which implies a very non-trivial connection between the UV and IR behaviors of the...
We present a comprehensive non-perturbative study of the phase structure of the asymptotically safe Standard Model. The physics scales included range from the asymptotically safe trans-Planckian regime in the ultraviolet, the intermediate high energy regime with electroweak symmetry breaking to strongly correlated QCD in the infrared. All flows are computed with a self-consistent functional...
Effective field theories of QCD, such as soft collinear effective theory with Glauber gluons, have led to important advances in understanding of many-body nuclear effects. We provide first applications to QED processes. We study the exchange of photons between charged particles and the nuclear medium for (anti)neutrino-, electron-, and muon-induced reactions inside a large nucleus. We provide...
We introduce a new approach to renormalize physical quantities in curved space-time
by adiabatic subtraction. We use a comoving infrared cut-off in defining the adiabatic counterpart of
the physical quantity under consideration. We show how this infrared cut-off should be used to
obtain a completely well-defined renormalization scheme and how it is fundamental to avoid...
The origins of the light neutrino masses, and the baryon asymmetry of the Universe remain some of the biggest open questions of particle physics. By extending the standard model with Majorana neutrinos, the light neutrino masses can be generated through the type-I seesaw mechanism, and the baryon asymmetry of the Universe through leptogenesis. We study low-scale leptogenesis with Majorana...
The Type II Seesaw Mechanism provides a minimal framework to explain the neutrino masses involving the introduction of a single triplet Higgs to the Standard Model. However, this simple extension was believed to be unable to successfully explain the observed baryon asymmetry of the universe through Leptogenesis. In our previous work (Phys. Rev. Lett. 128, 141801), we demonstrated that the...
The Standard Model (SM) of Particle Physics cannot account for the long-standing conundrums of the nature of dark matter (DM) and of the obvious imbalance between matter and antimatter in our Universe. Therefore, in this work, I will discuss the Inert Doublet Model (IDM), augmented with higher-dimensional operators, tied either to the SM gauge sector and inducing CP violation or to the SM...
Topological defects can act as local impurities that seed cosmological phase transitions. In this talk we will focus on how domain walls can affect the electroweak phase transition in the minimal singlet-scalar extension of the SM (xSM) with a $Z_2$ symmetry. When the transition is two-step, the early breaking of the $Z_2$ implies the formation of domain walls which subsequently act as seeds...
Higgs precision measurements and resonance searches at the LHC have made sharper than ever the electroweak naturalness problem. In response, the particle physics community has begun to question symmetry-based solutions. We provide a new perspective by proposing a symmetry-based framework which does not require any fine-tuning to comply with current experimental observations. This is achieved...
We investigate the predictions for various nucleon decay rates in non-supersymmetric SU(5) models, where the masses of the third and second family down-type quarks and charged leptons each stem dominantly from single GUT operators and present a "fingerprinting" method to distinguish between GUT models with different flavor structure with the use of future experimental nucleon decay results.
In this talk I will discuss recent results [1] on the mass scales in the $SO(10)$ grand unified theory based on the following minimal Higgs representation content: adjoint $45_H$, spinor $16_H$ and complex vector $10_H$, with higher-dimensional operators on top of renormalizable interactions. Consistency of the theory requires a scalar doublet leptoquark, a scalar gluon octet and a scalar weak...
It is remarkable that the matter fields in the Standard Model (SM) are apparently unified into the SU(5) representations. A straightforward explanation of this fact is to embed all the SM gauge groups into a simple group containing SU(5), i.e., the grand unified theory (GUT). Recently, however, a new framework “fake GUT” has been proposed. In this new framework, the apparent matter unification...
Magnetic monopoles are inevitable predictions of GUT theories. They are produced during phase transition in the early universe, but also mechanisms like Schwinger effect in strong magnetic fields could give relevant contributions to the monopole number density. I will show that from the detection of intergalactic magnetic fields of primordial origin we can infer additional bounds on the...
Black holes are considered to be exceptional due to their time evolution and information processing. However, it was recently proposed that these properties are generic for objects, the so-called saturons, that attain the maximal entropy permitted by unitarity. We verify this connection within a renormalizable $SU(N)$ invariant theory. We also review the concept of saturation of the universal...
We discuss the correspondence Between Black holes and Saturons, states that attain the maximal entropy permitted by unitarity. We present the connection within a renormalizable SU(N) invariant theory. We show that the spectrum contains a tower of bubbles representing bound states of SU(N) Goldstones. We argue that a saturated bound state exhibits a striking resemblance with a black hole. The...
Oscillons are oscillating, localized configurations in real scalar field theories. They appear in potentials that are shallower than quadratic away from the minimum and can be extremely long-lived.
Since plateau models are of great relevance for inflation, oscillons have been shown to form efficiently during preheating in a wide range of such models.
Most work on oscillons has focused...
Coherent states are generally deemed to be adequate quantum counterparts to classical configurations and their evolution provides a good description of systems in which cumulative quantum effects could lead to the break-down of the classical description. In this talk, by focussing on a $\lambda \phi^4$ theory, I will discuss the dynamics of the coherent state corresponding to a homogeneous...
We study kink-antikink scattering in the sine-Gordon model in the presence of interactions with an additional scalar field, ψ, that is in its quantum vacuum. In contrast to the classical scattering, now there is quantum radiation of ψ quanta and the kink-antikink may form bound states that resemble breathers of the sine-Gordon model. We quantify the rate of radiation and map the parameters for...
Various precision observables, such as flavour changing decays, are
generated at one-loop level in the Standard Model and their
renormalisation involves cancellations between purely bosonic and
fermionic interactions. In this talk I will show how perturbative
unitarity constraints can be used to derive renormalised matching
conditions for generic theories. These general results comprise...
