Overview
- DES measures S8 = 0.789 ± 0.012 and Ωm = 0.333^{+0.023}_{-0.028} in ΛCDM, a 1.8σ difference from combined Planck, ACT, and SPT CMB datasets (2.6σ when projected into S8).
- Combining DES 3×2pt with its supernovae, BAO, and cluster probes increases the parameter difference to 2.8σ relative to the CMB, whereas adding selected low‑redshift datasets yields 2.3σ.
- A global fit with DES Y6, primary CMB, and low‑redshift data tightens ΛCDM to S8 = 0.806^{+0.006}_{-0.007}, Ωm = 0.302 ± 0.003, h = 0.683^{+0.003}_{-0.002}, and Σmν < 0.14 eV (95% CL).
- In wCDM, the combined datasets give w = −0.981^{+0.021}_{-0.022}, consistent with a cosmological constant within uncertainties.
- The analysis spans ~5000 deg² using ~140 million source shapes and ~9 million lens galaxies, achieves high signal‑to‑noise in galaxy–galaxy lensing (173) and clustering (149), and passes extensive validation of baryonic and bias modeling with conservative scale cuts.