Chudaykin A., Gorbunov D., Nedelko N. «Exploring Λ CDM extensions with SPT-3G and Planck data: 4σ evidence for non-zero neutrino masses and implications of extended dark energy models for cosmological tensions» Журнал экспериментальной и теоретической физики, 168, № 6, с. 790-832 (2025)

We present cosmological constraints in the Λ CDM model and a set of its extensions from a dataset based on the polarization and gravitational lensing measurements from the South Pole Telescope and the large-scale (l<1000) part of the Planck CMB temperature measurements. In all cosmological scenarios, this CMB data combination brings the clustering measurements into agreement with the low-redshift probes of large-scale structure, resolving the S8 tension. Combining this CMB set with a full-shape treatment of the BOSS large-scale structure observations, additional BAO measurements, information from weak lensing and photometric galaxy clustering surveys, and the Pantheon supernova catalog, we find a ∼4σ preference for non-zero neutrino mass, ∑√_u=0.221±0.055 eV. We also explore dynamical dark energy in the context of the Hubble tension with two phenomenological late-time approaches introducing a phantom crossing in the dark energy equation of state. For the combination of all data considered, both models predict H₀≃68 km,·s^–1Mpc in ∼3σ tension with the SH0ES constraint, if the supernova absolute magnitude MB is calibrated by CMB and LSS data as a free parameter. While it is possible to achieve H0 values consistent with SH0ES by fixing MB to the Cepheid-derived value, that is shown to not be a valid approach as it introduces an implicit 4.5σ tension between CMB and the local Universe.

Moiseev I.A., Sazhina O.S. «Constraints on Wormhole Formation from Phantom Dark Energy in DESI» Журнал экспериментальной и теоретической физики, 168, № 6, с. 833-842 (2025)

For dark energy (DE) being a dynamical field, an equation-of-state parameter w<–1 leads to the phantom DE state, allowing wormhole (WH) throats to be stabilized effectively. We investigated the possibility of the existence of traversable WHs, whose stability is fully ensured by phantom DE, the dominance of which was recently indicated by the DESI project. Within the framework of the simple Morris-Thorne model, we derived a phenomenological relation connecting the throat radius b with the energy density of the phantom dynamical field ρ_ph(z). This establishes a direct connection between cosmological parameters and the properties of traversable WHs, showing that phantom DE could, in principle, serve as the exotic matter required to sustain WHs with throat sizes spanning from the gravitational radii of stellar-mass BHs and SMBHs up to cosmological scales. We investigated possible WH formation channels and showed extreme suppression of two mechanisms (Euclidean instanton tunneling and thermal fluctuation nucleation). Using gravitational lensing SQLS constraints on Ellis-Bronnikov WHs, we quantified the fraction of phantom energy that can be trapped in such WHs, f≈10^–11, indicating that only a small fraction of the phantom DE can be trapped in WH throats. Overall, our results show both the theoretical consistency and the observational limitations of phantom-supported WHs.