New Theory Explains How Time Began

TL;DR

Perimeter Institute researchers use quadratic gravity to explain the Big Bang, where 4D space developed a time dimension via quantum fluctuations.

Key Points

• 1.Standard quantum gravity breaks down exactly where it's needed most. Einstein's General Relativity can be quantized, but the result fails inside black holes and at the Big Bang — precisely the high-curvature scenarios requiring it.
• 2.Quadratic gravity offers a dimensionless coupling constant, making it quantum-compatible. Unlike Newton's constant, the coupling in quadratic gravity has no units, producing a well-behaved quantum theory — though one not yet compatible with observed low-energy gravity.
• 3.The new theory proposes time itself emerged from a 4D spatial universe via quantum fluctuations. At a boundary in that space, one dimension converted into time; quantum properties then drove rapid inflation, which stopped and converted energy into matter, radiation, and dark matter.
• 4.The theory solves multiple cosmological problems but has one key gap. It explains the Big Bang, inflation, matter origin, and avoids quantum gravity issues, and makes gravitational wave predictions — but the transition between Einstein and quadratic gravity is assumed, not derived.