Dark Energy: Constancy Questioned ⚡ экспресс
The study presents statistically significant evidence for dynamic dark energy conflicting with ΛCDM. Using MCMC analysis of DESI DR2 data (baryon acoustic oscillations), Type Ia supernovae, and compressed CMB likelihoods, models were tested: ω0ωaCDM, logarithmic, exponential, JBP, BA, and non-flat cosmologies. Results confirm a flat universe and give strong indications that ω ≠ -1, favoring the Quintom-B scenario (ω0 > -1, ωa < 0, ω0+ωa < -1). Upper limits on the sum of neutrino masses were obtained: <0.066 eV for ΛCDM and <0.075 eV for ωCDM from CMB+DESI DR2; in non-flat oΛCDM and oωCDM models they weaken to <0.263 and <0.520 eV; for others — from 0.043 to 0.127 eV. The number of relativistic species Neff remains standard (3.044). Bayesian analysis adding supernova samples DES-SN5Y or Union3 reveals measurable deviations from ΛCDM. Although no model reaches 5σ, discrepancies exceed 3σ, pointing to 'cracks' in the cosmological constant paradigm.
Previously, cosmologists imagined dark energy as a steady breeze, uniformly inflating the Universe like a balloon. The discovery of accelerated expansion, made by Adam Riess and Saul Perlmutter at the end of the 20th century, only reinforced this picture.
But a summary of fresh data—from supernova explosions to galaxy maps and echoes of the Big Bang—tells a different story. Studying the light of millions of galaxies (the DESI instrument, spectroscopy) revealed: the force inflating the balloon was pulsing. In the past, the pressure was slightly weaker, then strengthened, but now it may be weakening again.
🎯 If dark energy is indeed inconstant, the Universe's finale could be different: expansion isn't eternal—after trillions of years it might slow down, and galaxies will start approaching each other, triggering a reverse collapse.