Rare decays of B mesons provide sensitive probes of physics beyond the Standard Model. Since many years, measurements of angular observables in the decay B -> K* mu mu by the LHCb experiment have attracted considerable attention, in particular due to the persistent discrepancy in the observable P5'. More recent results also hint at a non-zero value for the observable S7, raising important...
In this talk I will review aspects of the inflationary Schwinger effect and its implications for dark matter. As part of this I will review the calculation of the Schwinger current in de Sitter space and show how peculiar IR divergences found in previous calculations can be cured. I will then review how the dark matter relic abundance can be generated through the inflationary Schwinger effect...
The QCD axion provides a compelling solution to the strong-CP problem and a leading dark-matter candidate. Its relic abundance depends on the epoch of Peccei–Quinn symmetry breaking and the thermal history of the early Universe. This talk examines how axion dark matter can populate the 0.49–1.49 μeV mass window targeted by haloscopes in Frascati National Laboratories. Although standard...
Dwarf galaxies evolve in diverse environments and serve as important probes of dark matter physics and galaxy formation. In this talk, I will present the environmental evolution of dwarf galaxies within a two-component self-interacting dark matter (SIDM) model featuring mass segregation. In this model, energy exchange between heavy and light dark matter particles causes the heavier component...
Suggestions of a late-time phantom crossing from DESI baryon acoustic oscillation measurements, combined with cosmic microwave background and Type-Ia supernova observations, have renewed interest in non-standard dark energy models. In this Letter, we propose a new realization of a low redshift phantom crossing using only well understood ingredients from fermion condensation and general...
With observations of solar neutrinos in direct dark matter detection, the search for dark matter is beginning to fog. This irreducible neutrino fog presents an new probe into neutrino physics. In this talk, we explore the potential of current and next-generation xenon-based detectors to constrain and discover non-standard neutrino interactions (NSI). We present new limits on NSI couplings and...
The ultra-high-energy event KM3--230213A has been attributed
to dark matter (DM) decay, despite arriving opposite the
Galactic Centre. We construct a per-event test statistic to
quantify this hypothesis and forecast the events needed to exclude
it in favour of an isotropic signal. The single observed event
disfavours but does not exclude DM decay ($p_{\rm DM}\simeq0.13$--$0.15$)....
The diffusion of high-energy cosmic rays (CRs) through the dark matter (DM) spikes of active galactic nuclei entails significant energy loss via interactions with DM. While previous studies of sub-GeV DM have focused on elastic scattering, this process becomes insufficient at higher proton energies and DM masses. In this work, we investigate the CR-DM deep inelastic scattering (DIS) as...
We discuss the ultraviolet fixed point of asymptotically safe dilaton quantum gravity. It differs from the Reuter fixed point by the dependence of the Planck mass on a scalar field. The gauge invariant functional flow equation in the most general approximation with up to two derivatives strengthens the argument for the existence of this fixed point. The quantum effective action obtained from...
Recent studies of Galactic surveys, such as Gaia, have revealed that the Milky Way's gravitational potential comes from a matter distribution that is triaxial and rotated with respect to the Galactic center-Sun axis. This, in turn, could mean that the dark matter halo also shares these properties. In this talk, I will discuss e.g. the compatibility of the morphology of the Galactic Center...
We use modular symmetry as an organizing principle that attempts to simultaneously address the lepton flavor puzzle, inflation, and post-inflationary reheating. We demonstrate this approach using the finite modular group $A_4$ in the lepton sector. In our model, neutrino masses are generated via the Type-I see-saw mechanism, with modular symmetry dictating the form of the Yukawa couplings and...
Equal-time in-in correlation functions are important observables for cosmological models and quantum field theories. In this talk, I will first explore how the Wilsonian renormalization group and effective field theory (EFT) apply to these observables in both flat and de Sitter space. Specifically, matching the UV and IR requires additional terms not captured by conventional EFT. These terms...
We propose a novel mechanism for achieving the required kinetic equilibrium between dark matter and a radiation bath during the freeze-out of self-annihilating dark matter. This mechanism arises naturally in a class of strongly coupled models containing nearly massless axions. Focusing on a strongly interacting massive particle (SIMP) scenario augmented by a dark axion, we demonstrate that the...
Determining the leptonic CP-violating phase $\delta_{\rm CP}$, the atmospheric mixing angle $\theta_{23}$, and the mass-squared difference $\Delta m^2_{31}$ with high precision is a central goal of current and next-generation long-baseline neutrino experiments. In this work, we investigate the fundamental information content of three-flavor neutrino oscillations within the framework of quantum...
We demonstrate for the first time that new physics explaining the long standing charged $B$ meson anomalies, $R(D^{(*)})$, can be the source of CP violation that explains the observed baryon asymmetry of the universe (BAU). We consider the general two Higgs doublet model with complex Yukawa couplings and compute the BAU in the semiclassical formalism, using a novel analytic approximation for...
The Standard Model (SM) gauge theory with dynamical matter fields possesses an electric one-form $\mathbb{Z}_{6}$ symmetry, characterized by its action on Wilson line operators. At finite temperature, compactification on the thermal circle gives rise to a corresponding 0-form symmetry, whose spontaneous breaking can lead to the formation of domain walls. In this talk, I will focus on its...
When data anomalies are observed, it is a common practice to assume some toy models, simplified models, or EFT and interpret the anomalies. In particular, one tends to minimize the number of new physical degrees of freedom, as well as the number of couplings. In this talk, I will describe a few examples in physics of flavors and dark matter, where this simple-minded approach leads to incorrect...
Large curvature perturbations generated during slow first-order phase transitions are a promising source of primordial black holes. However, recent analyses suggested that the mechanism is ruled out once the density contrast and the formation threshold are evaluated in the same gauge. In this work, we show that this mechanism remains viable: after a supercooled transition, reheating can be...
In this talk, I first introduce the hydrodynamic sound-shell model for gravitational waves from sound waves of first-order phase transitions, then we investigate the primordial black hole formations from the delayed-decay regions of first-order phase transitions, next we study the scalar-induced gravitational waves with non-Gaussianity up to all orders, and finally we propose sound-wave...
We revisit several minimal extensions of the Standard Model for dark matter. Depending on time, we discuss some or all of the following: (i) a scalar dark matter with higher-dimensional operators, where thermal misalignment provides a viable production mechanism; (ii) Majorana fermion dark matter with a coannihilating scalar, with the bino-slepton scenario in supersymmetry as a concrete...
I will present my recent works on Probing Ultralight Dark Matter with Laser Interferometers in Space.
Novel signature of axion-like particles at neutrino experiments
Coherent elastic neutrino–nucleus scattering (CEνNS) provides a powerful probe of Standard Model neutral-current interactions, neutrino properties, nuclear structure, and new physics. In this talk, I will present a comprehensive EFT framework for CEνNS that systematically connects high-energy ultraviolet scenarios to low-energy nuclear recoil observables. By incorporating LEFT operators up to...
We present a phenomenological study of partonic spin correlations and CP properties in H->gg decay channel at future lepton colliders. We investigate two classes of observables: Lund observable defined based on subjets and four-point energy-energy correlator (E4C) between particles inside two jets. Our results show that the E4C with energy weighted to the power of n = 4 achieves the strongest...
Ultra-high-energy cosmic rays (UHECRs) can boost relic neutrinos to high energies through Standard Model (SM) neutral-current interactions, providing an indirect probe of the cosmic neutrino background (CνB). In this talk, I will discuss a systematic study of the diffuse UHECR-boosted CνB flux including elastic neutrino-nucleon scattering (ES), coherent elastic neutrino-nucleus scattering...
QCD spin effects play a crucial role in probing nuclear structures and have been extensively studied in hadronic physics. However, their potential for exploring new physics beyond the Standard Model and quantum entanglement phenomena has been largely overlooked. In this talk, I will discuss how transverse spin effects—encoded in quark fragmentation functions—can probe electroweak dipole...
Millicharged particles with tiny electric charge $q_\chi$ have garnered significant attention due to their profound implications for physics beyond the Standard Model. In this talk, I will present a direct laboratory search for such particles via Schwinger pair production using correlated quantum sensors. In the low-mass regime below $4.0 \times 10^{-5}$ eV, our approach provides a...
In this talk, I discuss a new scenario that explains the baryon asymmetry of the Universe through a minimal extension of the Standard Model (SM). In this scenario, all three Sakharov conditions are simultaneously satisfied during the decoupling of CP-violating electroweak (EW) sphaleron processes. As the source of the CP asymmetry in the EW sphaleron process, we consider an effective theory in...
The microscopic nature of dark matter is the major open question in science. Weakly-Interacting Massive Particles (WIMPs) and Axion-Like Particles (ALPs) are the two most theoretically motivated dark matter candidates. Thousands of papers consider them separately. We point out that if both species are present in the theory, even a tiny (Planck-suppressed) interaction between them could lead to...
First-order phase transitions in the early Universe are ubiquitous from the viewpoint of particle physics. Particle production during the nucleation and collision of bubbles has beed widely discussed. In this talk, we focus on fermion production induced by relativistic bubble collisions. The post-collision scalar-field dynamics in the planar approximation are described well in terms of Milne...
The existence of a landscape of metastable vacua raises the possibility that our Universe may have undergone quantum vacuum decay at late times. This work explores how such a transition can be tested with cosmological observables, focusing on precision distance measurements and cosmic microwave background (CMB) anisotropies. A set of phenomenological models is constructed in which late-time...
In this talk, I will discuss how primordial black holes (PBHs) and their associated stochastic gravitational-wave backgrounds can probe the post-inflationary Universe. I will first consider PBH formation during a non-standard reheating phase, where an enhanced primordial scalar power spectrum can simultaneously generate PBHs and scalar-induced gravitational waves. Accounting for uncertainties...
Quadratically coupled ultralight scalar dark matter behaves as a coherent classical field whose interactions with matter can induce a composition-dependent force through the dark matter background. We present a complete calculation of this background-induced force beyond the spherically symmetric approximation. Using a partial-wave treatment of dark-matter scattering, we determine its angular...
The bubble wall velocity is a key parameter in cosmological first-order phase transitions, affecting both electroweak baryogenesis and gravitational-wave signals. However, it is often treated as an external input in phenomenological studies, while a self-consistent determination remains challenging. In this work, we investigate the bubble wall dynamics in the New Physics Model. The microscopic...
We propose a new mechanism for dark matter genesis, Defect-Mediated Conversion (DMC). Cosmological domain walls–generic remnants of spontaneously broken discrete symmetries–can host a scalar condensate in their core that acts as a portal between the Standard Model and a dark sector: thermal-bath fermions crossing the wall are partially and non-thermally converted into dark particles. The...
The orbital evolution of the Hulse-Taylor binary neutron star system is described with high precision by General Relativity, in which gravity is the only long-range force and gravitational waves provide the dominant energy-loss channel. We use this precision test of relativistic binary dynamics to derive new constraints on axion couplings to stable neutron-star constituents: neutrons,...
We study a fermionic dark matter candidate that couples to the standard model particles exclusively through electric and magnetic dipole operators mediated by a massive dark photon. Such dipole portals naturally arise in dark sectors where the dark matter is neutral under a hidden U(1)D, and they lead to phenomenology distinct from conventional vector-current interactions. We consider the...
We investigate non-thermal particle production during first-order phase transitions in the presence of ultra-relativistic thick bubble walls with non-trivial internal structure. Extending the framework of bubble-expansion particle production, we consider bubble walls containing multiple ripples and study how such spatial modulations affect the production of heavy particles coupled to the order...
I will go through the list of new physics search results at the LIGO-Virgo-KAGRA collaborations, which includes searches for early universe phase transitions, topological defects, searches for various species of dark matter, etc.
The nature of dark matter (DM) remains one of the most critical challenges in modern physics. Macroscopic DM present a compelling alternative to conventional particle DM, yet their terrestrial
search is notoriously challenging due to low number density. We presents a unified, multimessenger search strategy for macroscopic DM, dramatically improving existing constraints and proposing a new...
This talk gives a unified perspective on the phase transitions, gravitational waves, and dark matter detection prospects of strongly coupled dark sectors. I first review lattice-informed effective descriptions of dark confinement and chiral dynamics, and show how the resulting first-order transitions generate observable gravitational wave signals, strongest in the near-conformal, strongly...
It is well known that unbroken global symmetries of the lagrangian remain unbroken under RG evolution. Less appreciated is the fact that certain relations can be RG-stable even without any symmetry transformation of the field content of the model. Recently, a renewed interest in this topic was sparked by the observation of a family of all-order RG-stable relations in the 2HDM scalar sector...
3-form dark energy is similar to but distinguishable from a scalar field in an expanding universe, and its tensorial structure allows for unique couplings that cannot be experienced by canonical scalars. We here explore the possibility that 3-form dark energy can explain the cosmic birefringence angle $\beta\sim0.3^\circ$, as suggested by observations of the CMB polarization. We consider two...
This talk will present the latest phenomenological and simulated experimental prospective studies on the new physics opportunities at DarkSHINE Experiment by exploring the physics sensitivity of searching for dark fermions/sterile neutrinos and utilizing the positron beam mode to search for Dark Photon invisible decay signals in comparison with electron beam mode sensitivities.
We investigate the complex singlet extension of the Standard Model, which provides a scalar dark matter candidate. We impose the constraints from the observed relic abundance together with the most stringent limits from direct detection experiments on the model. The counterterms
are determined so that the vacuum and mass conditions are consistently satisfied at one-loop order, and the...
We present a novel framework of the post-inflationary composite axion to address the strong CP problem without the cosmological domain wall problem. Conventional composite axion models lead to the domain wall number greater than one, producing stable axion domain walls that overclose the Universe. We show that by considering a special embedding of the confining gauge group responsible for the...
arXiv:2602.23991 (Accetped by PRL)
We presents a combination of searches for Higgs boson pair (HH) production performed by the ATLAS and CMS Collaborations using proton-proton collision data sets recorded at √s = 13 TeV during the Large Hadron Collider Run 2, corresponding to integrated luminosities ranging between 126 and 140 $fb^{−1}$. The upper limit at the 95% confidence level on the...
The talk is devoted to the role of excited final nuclear states in WIMP-nucleus scattering. We generalize the formalism of non-relativistic effective field theory to inelastic scattering and apply the state-of-the-art Relativistic Configuration-interaction Density functional theory to evaluate the event rates in direct detection experiments. We show that for certain interaction operators, the...
arxiv:2608.03369 (submitted to JHEP)
A measurement of the $H\rightarrow \gamma^{*}\gamma$ process in the $\ell\ell\gamma$ final state is performed using proton--proton collision data recorded with the ATLAS detector at $\sqrt{s}$ = 13.6 TeV during the years 2022--2024, corresponding to an integrated luminosity of 164 fb$^{-1}$. A simultaneous unbinned maximum-likelihood fit to the...
Small instantons can significantly modify the axion potential in KSVZ models containing vector-like quarks (VQs). Using naive dimensional analysis, we analyse models with a single VQ, multiple identical copies, and sets of distinct VQs, while requiring the gauge couplings to remain perturbative up to the Planck scale under two-loop running. Their differing fermion zero-mode structures require...
We explore $U(1)_{L_e-L_\mu}$ gauge extension of the Standard Model with particle content enlarged by three neutral fermions, of which the lightest one contributes to dark matter content of the Universe. The scalar sector is enriched with a $\tilde{R}_2$ scalar leptoquark doublet to investigate flavor anomalies in $B$-meson sector and a scalar singlet to spontaneously break the new $U(1)$. We...
This work explores the production of MeV-scale electrophilic axion-like particles (ALPs) by utilizing the monochromatic 5.5 MeV photon resulting from the nuclear fusion processes in the Sun. These 5.5 MeV photons can undergo Compton-like scattering with the ambient electrons in the solar matter to produce a substantial flux of MeV ALPs. Upon reaching the Earth, such ALPs can be detected via...
Dark matter could consist mainly of magnetic monopoles of a dark non-abelian gauge group. These dark monopoles could be produced during a thermal phase transition in the early Universe. We show that, in a minimal model and with quite general assumptions, this scenario cannot be realized, since the dark matter abundance is always dominated by dark gauge bosons. In a non-minimal extension of the...
