We introduce a new approach for nonparametric spectral density estimation based on the subsampling technique, which we apply to important class of nonstationary time series. These are almost periodically correlated sequences. In contrary existing methods, our technique does not require demeaning data. On simulated data examples, compare estimator function with classical one. Additionally, propo...

Spectral estimation of nonstationary but harmonizable processes is considered. Given a single realization of the process, periodogram-like and consistent estimators are proposed for spectral mass estimation when the spectral support of the process consists of lines. Such a process can arise in signals of a moving source from array data or multipath signals with Doppler stretch from a single rec...

Higlighting certain similarities between the two-dimensional Luttinger liquid model and the effective fermionic theory obtained from the hypercharge Lagrangian, we argue the case for a new type of Standard Model extension.