Results 71 to 80 of about 1,633 (195)
Reinforcement Learning for Jump‐Diffusions, With Financial Applications
Mathematical Finance, EarlyView.ABSTRACT We study continuous‐time reinforcement learning (RL) for stochastic control in which system dynamics are governed by jump‐diffusion processes. We formulate an entropy‐regularized exploratory control problem with stochastic policies to capture the exploration–exploitation balance essential for RL.
Xuefeng Gao, Lingfei Li, Xun Yu Zhou
wiley +1 more source
The Born regime of gravitational amplitudes
Journal of High Energy PhysicsWe study the 2 → 2 scattering in the regime where the wavelength of the scattered objects is comparable to their distance but is much larger than any Compton wavelength in the quantum field theory.
Miguel Correia, Giulia Isabella
doaj +1 more source
d-dimensional SYK, AdS loops, and 6j symbols
Journal of High Energy Physics, 2019 We study the 6j symbol for the conformal group, and its appearance in three seemingly unrelated contexts: the SYK model, conformal representation theory, and perturbative amplitudes in AdS.
Junyu Liu +3 more
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Fortschritte der Physik, Volume 74, Issue 4, April 2026.Abstract String theory has strong implications for cosmology, implying the absence of a cosmological constant, ruling out single‐field slow‐roll inflation, and that black holes decay. The origins of these statements are elucidated within the string‐theoretical swampland programme.
Kay Lehnert
wiley +1 more source
Spectral Irradiance Observations and Projections for Solar Cycle 25
Earth and Space Science, Volume 13, Issue 4, April 2026.Abstract The Ozone Monitoring Instrument (OMI) on the Aura satellite makes near‐daily measurements of solar spectral irradiance (SSI) at wavelengths between 265 and 500 nm for instrument calibration purposes. The low degradation and exceptional stability of OMI's calibration during its lifetime facilitates the creation of a new 18‐year OMI Version 7 ...
Matthew T. DeLand +3 more
wiley +1 more source
Financial Time Series Uncertainty: A Review of Probabilistic AI Applications
Journal of Economic Surveys, Volume 40, Issue 2, Page 915-953, April 2026.ABSTRACT Probabilistic machine learning models offer a distinct advantage over traditional deterministic approaches by quantifying both epistemic uncertainty (stemming from limited data or model knowledge) and aleatoric uncertainty (due to inherent randomness in the data), along with full distributional forecasts.
Sivert Eggen +4 more
wiley +1 more source
The propagator seagull: general evaluation of a two loop diagram
Journal of High Energy Physics, 2019 We study a two loop diagram of propagator type with general parameters through the Symmetries of Feynman Integrals (SFI) method. We present the SFI group and equation system, the group invariant in parameter space and a general representation as a line ...
Barak Kol, Ruth Shir
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SPIN FOAMS AS FEYNMAN DIAGRAMS
2001: A Relativistic Spacetime Odyssey, 2003 It has been recently shown that a certain non-topological spin foam model can be obtained from the Feynman expansion of a field theory over a group. The field theory defines a natural ``sum over triangulations'', which removes the cut off on the number of degrees of freedom and restores full covariance.
Reisenberger, Michael, Rovelli, Carlo
openaire +2 more sources
Advanced Functional Materials, Volume 36, Issue 20, 9 March 2026.This study uncovers a new switching mechanism in HfO2 and ZrO2, where the absence of a non‐polar layer along the a‐direction induces interaction between polar layers. Consequently, the switching barriers for growth are lower than those for nucleation in this direction, leading to a size‐dependent coercive field that matches experimental observations ...
Kun Hee Ye +6 more
wiley +1 more source
Advanced Functional Materials, Volume 36, Issue 21, 12 March 2026.By a simple anti‐Galvanic reaction, up to six copper atoms could be preferably doped into the Ag2(SR)5 staple motifs and Ag20 dodecahedral shell of an atomically precise Ag44(SR)30 nanocluster. When anatase TiO2 is used as substrate, the (AgCu)44/TiO2 photocatalyst exhibited much improved activity in photocatalytic CO2 reduction compared to Ag44/TiO2 ...
Ye Liu +5 more
wiley +1 more source