A unified cosmological model is proposed, in which the pre-inflationary stage (from the Planck time) and the onset of inflation are described by a single scalar field. In the early phase, expansion decelerates and the comoving Hubble horizon grows, then inflation smoothly kicks in. This alters the causal structure and naturally suppresses correlations at angles θ > 60° in the cosmic microwave background observed by Planck. Quantum fluctuations are analyzed in the Mukhanov-Sasaki formalism with canonical quantization that minimizes energy. The vacuum state is defined only for modes that are inside the horizon at the start of inflation, which induces a natural cutoff in the primordial power spectrum. The spectrum is suppressed on large scales and nearly scale-invariant on small scales, reproducing the standard de Sitter limit in agreement with observations.
The birth of the universe resembles not an explosion, but a traffic jam. At first, a tiny fraction of a second after the Big Bang, space expanded sluggishly, like cars stuck in gridlock. Then came a sharp surge—accelerated expansion, which cosmologists call inflation. This contrasting transition explains an ancient mystery: why there are no large spots in the snapshot of the universe's microwave 'echo.' The slow phase acted like a filter, preventing large energy fluctuations from growing. Only fine ripples remained—the very quantum jolts from which galaxies later emerged. Remarkably, without such a jam, the familiar cosmos might never have formed: all matter would have collapsed into giant black holes or remained a diffuse fog. The new model, consistent with Planck satellite data, was developed by Alan Guth and others. Yet back in the 1940s this 'echo' was predicted by George Gamow, and in 1965 it was serendipitously detected by Arno Penzias and Robert Wilson.
🎯 A delay in the first minuscule fraction of a second shaped the cosmos: without this 'cosmic traffic jam,' stars might never have ignited at all.