This paper aims to study data driven model selection criteria for a large class of time series, which includes ARMA or AR(∞) processes, as well GARCH ARCH(∞), APARCH and many others processes. We tackled the challenging issue designing adaptive enjoys strong consistency property. When observations are generated from one aforementioned models, new criteria, select true almost surely asymptotical...

We build a model in which the relic abundance of axions is altered from standard misalignment mechanism, either increased or decreased, due to presence new light scalar that couples radial part Peccei-Quinn (PQ) field. The makes effective PQ symmetry-breaking scale dynamical, altering early-time dynamics for axion and affecting its late-time dark matter abundance. analyze this mechanism semiana...

We argue that sufficiently complex grand unified theories involving extra strong intractions that confine at very short distances, may lead to a heavy axion solution of the CP problem of QCD. This axion may have a mass within accessible energy range, and its low energy interactions emerge through mixing with axial Higgs boson(s). Another signature of this scenario is softly broken Peccei—Quinn ...