The Lambda-CDM (ΛCDM) model has been the foundation of modern cosmology for some time now, successfully describing large-scale structures in the Universe.
It proposes that 95% of the cosmos is composed of dark matter (25%) and dark energy (70%). Dark energy, represented by the cosmological constant (Λ), is thought to drive the accelerating expansion of the Universe, maintaining a constant energy density over time. However, new results from the Dark Energy Survey hint at a deviation from this assumption, suggesting that dark energy might evolve over time. The Dark Energy Survey (DES) was conducted using the 570-megapixel Department of Energy-fabricated Dark Energy Camera (DECam), mounted on NSF's Víctor M. Blanco 4-m telescope at Cerro Tololo Inter-American Observatory, a Program of NSF NOIRLab. By taking data on 758 nights across six years, the DES scientists mapped an area almost one-eighth of the entire sky. The project employs multiple observational techniques, including supernova measurements, galaxy clustering analysis, and weak gravitational lensing, to study dark energy. Two key DES measurements — Baryon Acoustic Oscillations (BAO) and distance measurements of exploding stars (Type Ia supernovae) — track the Universe's expansion history. BAO refers to a standard cosmic ruler formed by sound waves in the early Universe, with peaks spanning approximately 500 million…