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Creating kinks with quantum mediation
We consider the creation of kink-antikink pairs of a scalar field ϕ by the scattering of classical wave packets of a second scalar field ψ when there are no direct interactions between ϕ and ψ . The creation becomes possible only due to a quantum field that interacts with both ϕ and ψ . We scan parameter space and find it favorable for kink production when the initial wave packets have large total energy and wide spatial extent but scatter at low velocities. Published by the American Physical Society 2024
UV massive resonance from IR double copy consistency
From the perspective of effective field theory (EFT), Wilson coefficients of the low energy theory are determined by integrating out modes of the full ultraviolet (UV) theory. The spectrum can be in principle resummed if one has access to all available infrared (IR) coefficients at low energies. In this work we show that there exists a general class of consistent massive resonance double-copy (CMRDC) models where UV massive residues are reconstructed through double-copy consistency conditions between the IR Wilson coefficients of the full EFT expansion. Through a color-dual bootstrap, we find surprisingly that double-copy consistency alone introduces the kinematic factors of CMRDC models that soften high energy behavior by exponentiating color-dual contacts. This bootstrap suggests that our massive resonance paradigm is an inevitable consequence of the duality between color and kinematics, thereby providing a path towards emergent UV structure directly from the IR. We then demonstrate how CMRDC models can capture a spectrum of massive modes compatible with general multiplicity, and use Padé extrapolation to solve the inverse problem of identifying massive UV resonance from a small number of IR Wilson coefficients. Published by the American Physical Society 2024
Machine learning BPS spectra and the gap conjecture
We explore statistical properties of Bogomol’nyi-Prasad-Sommerfield q-series for strongly coupled supersymmetric theories that correspond to a particular family of three-manifolds. We discover that gaps between exponents in the -series are statistically more significant at the beginning of the -series compared to gaps that appear in higher powers of. Our observations are obtained by calculating saliencies of -series features used as input data for principal component analysis, which is a standard example of an explainable machine learning technique that allows for a direct calculation and a better analysis of feature saliencies.
Nonlinear Sigma model amplitudes to all loop orders are contained in the Tr ( Φ 3 ) theory
Scattering amplitudes for the simplest theory of colored scalar particles—the Tr ( Φ 3 ) theory—have recently been the subject of active investigations. In this work we describe an unanticipated wider implication of this work: the Tr ( Φ 3 ) theory secretly contains nonlinear sigma model (NLSM) amplitudes to all loop orders. The NLSM amplitudes are obtained from Tr ( Φ 3 ) amplitudes by a unique shift of kinematic variables. We show that this shifted kinematics produces amplitudes for a cubic theory with a linear term in the potential, with extrema spontaneously breaking U ( N ) → U ( N − k ) × U ( k ) . The Goldstone amplitudes for this theory coincide with those of pions in the U ( N ) × U ( N ) → U ( N ) chiral Lagrangian to all orders in the planar limit. We also give a purely on-shell understanding of this correspondence, showing that integrands defined by the kinematic shifts have the correct residues on poles and appropriately produce the Adler zero. Finally, we discuss how similar kinematic shifts produce certain infinite classes of mixed amplitudes of pions and Tr ( Φ 3 ) scalars, most of which are not interpretable from the Lagrangian description. Published by the American Physical Society 2024
Unitarity of bespoke amplitudes
We use partial wave unitarity to constrain various bespoke four-point amplitudes. We start by constructing bespoke generalizations of the type-I superstring amplitude, which we show satisfy dual resonance and have suitable high-energy limits. By analyzing the behavior of partial wave coefficients for highly massive states, we strictly rule out all bespoke amplitudes with asymptotically nonlinear Regge trajectories and place constraints on the first few nontrivial parameters in asymptotically linear cases. Finally, we argue that while a large class of unitary bespoke amplitudes fails to satisfy Regge sum rules, there exists a smaller subclass with a vanishing mass gap that is superpolynomially bounded.
Antipodal self-duality of square fishnet graphs
In strongly deformed planar 𝒩 = 4 super-Yang-Mills theory, or fishnet theory, a point-split single-trace correlation function of four dimension-𝑚 scalar operators is given by a single Feynman integral, which involves integrating over locations of a 𝑚 × 𝑚 grid of points. We show that for any integer 𝑚 this square fishnet graph is invariant under the combined action of a kinematic map and the antipode map of the Hopf algebra on multiple polylogarithms; i.e. it possesses an antipodal self-duality.
Origin of the Six-Gluon Amplitude in Planar N = 4 Supersymmetric Yang-Mills Theory
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Toward Complete Leading-Order Predictions for Neutrinoless Double β Decay
The amplitude for the neutrinoless double β (0νββ) decay of the two-neutron system nn → ppe – e – constitutes a key building block for nuclear-structure calculations of heavy nuclei employed in large-scale 0νββ searches. Assuming that the 0νββ process is mediated by a light-Majorana-neutrino exchange, a systematic analysis in chiral effective field theory shows that already at leading order a contact operator is required to ensure renormalizability. Here, we develop a method to estimate the numerical value of its coefficient (in analogy to the Cottingham formula for electromagnetic contributions to hadron masses) and validate the result by reproducing the charge-independence-breaking contribution to the nucleon-nucleon scattering lengths. Our central result, while derived in dimensional regularization, is given in terms of the renormalized amplitude Aν(|p|, |p'|) , matching to which will allow one to determine the contact-term contribution in regularization schemes employed in nuclear-structure calculations. Our results thus greatly reduce a crucial uncertainty in the interpretation of searches for 0νββ decay.
Elliptic, Yangian-Invariant “Leading Singularity”
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Dominance of Replica Off-Diagonal Configurations and Phase Transitions in a P T Symmetric Sachdev-Ye-Kitaev Model
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Time- and Space-Varying Neutrino Mass Matrix from Soft Topological Defects
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New Probe of Cosmic Birefringence Using Galaxy Polarization and Shapes
We propose a novel statistical method to measure cosmic birefringence and demonstrate its power in probing parity violation due to axions. Exploiting an empirical correlation between the integrated radio polarization direction of a spiral galaxy and its apparent shape, we devise an unbiased minimum-variance estimator for the rotation angle, which should achieve an uncertainty of 5°–15° per galaxy. In conclusion, large galaxy samples from the forthcoming SKA continuum surveys, together with optical shape catalogs, promise a comparable or even lower noise power spectrum for the rotation angle than in the CMB Stage-IV (CMB-S4) experiment, with different systematics.
Teleportation Systems Toward a Quantum Internet
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Universal CMB 𝐵-mode spectrum from early causal tensor sources
Many early Universe scenarios predict postinflationary tensor perturbations from causality-limited, subhorizon sources. While the microphysical details may be different, as long as these sources are bounded in duration and correlation length, their tensor power spectra exhibit a universal scaling behavior at small wave number: 𝒫 ℎ (𝑘)∝𝑘 3 , corresponding to white noise on superhorizon scales at the time of production. If these early causal tensor sources (ECTs) exclusively produce gravitational waves before redshift 𝑧 ∼10 5 , this scaling is realized on all of the scales observed in the CMB, and thus yields a universal multipole distribution for the 𝐵-mode angular power spectrum. Unlike the scale-invariant distributions of inflationary 𝐵 modes, ECTs generically predict enhanced power on small scales and suppressed power on large scales, which allows these source classes to be distinguished given measurements over a sufficient range of angular scales. In this paper, we introduce a unified framework for characterizing ECTs and demonstrate how their universal infrared scaling manifests in low-frequency observables, including CMB 𝐵 modes and stochastic gravitational wave spectral densities. We illustrate this mapping with representative case studies of this universality class involving first-order phase transitions, topological defects, and enhanced scalar perturbations, which source tensor modes at second order in perturbation theory.
PV Modules Temperature Variation and Patterns in Medium and Utility-Scale Floating PV Systems
This paper presents the preliminary results and findings of the four operational Floating PV systems across the USA. At each site, temperature of five PV modules located at North-West, North-East, Middle, South-West, and, South-East have been monitored through the Resistant Temperature Detector (RTD) sensors. Three RTDs were attached to each PV module on the rear-side along the diagonal at top, middle and bottom cells. The preliminary results reveal wide temperature differences among the inter and intra PV modules. Besides this, wave pattern temperatures were observed in a few PV modules. The final results, findings, and, factors responsible will be investigated during the next few months.
Dynamics of quarks and gauge fields in the lowest-energy states in QED and QCD interactions
We examine the dynamics of quarks and gauge fields in the lowest energy states in the QED and QCD interactions by combining Schwinger’s longitudinal confinement in (1+1)D with Polyakov’s transverse confinement in (2+1)D in a “stretch (2+1)D” flux tube model in (3+1)D. For such QED and QCD systems in the flux tube configuration with cylindrical symmetry, we separate out the transverse and longitudinal degrees of freedom, approximate the non-Abelian QCD in the quasi-Abelian approximation, and solve the derived equations to study the collective excitations. Here, we find stable collective QED and QCD excitations showing up as confined QED and QCD mesons, in support of previous theoretical studies and recent observations of the anomalous hypothetical X17 and E38 particles. Future theoretical lattice gauge calculations of QED in (3+1)D with the inclusion of the Schwinger longitudinal confinement mechanism and experimental confirmation of the hypothetical X17 and E38 particles will shed definitive light on quark confinement in the QED interaction in (3+1)D.