Is the Expansion of the Universe Accelerating? (The Dark Energy Crisis, Pantheon+ & DESI Redshift Tension)
A cosmological and observational analysis of cosmic acceleration: from the 1998 Type Ia supernovae discovery and the cosmological constant Lambda ($Lambda$) to Pantheon+ recalibrations, dynamical dark energy (w(a)), and the Dark Energy Spectroscopic Instrument (DESI) baryon acoustic oscillation tensions.