BLUF

The rate of universe expansion, known as "Hubble tension," is a key cosmological question with notable uncertainty, reflecting discrepancies in measurements.

Summary

KEY POINTS:
  1. The proposed void is about a billion light-years in radius, with a density 20% below the universal average.
  2. The Modified Newtonian Dynamics (MOND) theory suggests gravity behaves differently in weak gravitational fields.
  3. A revised theory of gravity may be required.
READ: Is Earth inside a giant void? It could solve one of cosmology's biggest puzzles

References