Overview
- Researchers from the University of Waterloo and the Perimeter Institute report a Big Bang model where the early growth of the universe arises from gravity itself rather than an extra inflation field.
- The team uses Quadratic Quantum Gravity, which adds squared curvature terms to Einstein’s equations to keep the math stable at extreme energies like those at the universe’s birth.
- The framework predicts a minimum level of primordial gravitational waves, tiny ripples in spacetime from the first moments after the Big Bang that next-generation experiments could seek.
- The authors say they will sharpen the predicted signal and explore links to particle physics to help upcoming CMB maps and gravitational-wave observatories judge the idea.
- Coverage notes open questions in quadratic gravity such as so‑called ghost modes, which the paper acknowledges as an issue that may require strong coupling effects to contain.