Testing the Origin of Time: Falsifiable Predictions for the Universe’s First Moment

This paper makes testable predictions about the Big Bang itself. Instead of an explosion 13.8 Gyr ago, we recast the Big Bang as a temporal boundary where proper time cannot be extended backward, followed by a quantum selection event that sets the universe’s initial conditions. Entirely within GR, with no new gravitational degrees of freedom.

Key predictions (falsifiable this decade)

• Curvature floor (main test).
  The post-nucleation interior is open (saddle-shaped; negative spatial curvature) with a minimum present-day curvature

  Ωk,0=c∗ e−2Neff,c∗∈[10−4, 0.6]  ,Ωk,0=c∗e−2Neff,c∗∈[10−4,0.6],

  where NeffNeff encodes the early “roll” and thermal history. Next-generation surveys (e.g. CMB-S4, Euclid) approaching ∣Ωk∣∼10−4∣Ωk∣∼10−4 can decisively test this: a positive detection at that level supports the framework; no detection tightens the allowed early-roll (or c∗c∗) but remains consistent; a measurement of negative curvature would falsify the framework.

• Non-Gaussianity lock.
  Single-source evolution after selection implies the standard δNδN relation
  τNL=(6/5)2fNL2τNL=(6/5)2fNL2 at leading order; significant deviations point to extra light fields or non-BD initial states.

• Polarization null.
  Scalar/lapse-only dynamics imply TB/EB ≈ 0 at leading order; a robust primordial TB/EB detection would challenge the assumptions.

Why this matters

• Provides a concrete alternative initialization to standard inflationary starts, with a distinctive open-universe curvature floor.

• Turns “what happened at the beginning?” into measurable physics.

• Built within GR (lapse/shift remain constraints); the novelty is the time-first formulation and boundary-and-selection start.

Technical approach. We use Coleman–De Luccia/Hawking–Moss nucleation to select finite-lapse initial data; analytic continuation yields an open FRW interior whose curvature dilutes predictably through cosmic evolution, giving the testable floor above. We bracket the geometry factor c∗c∗ with a thin-wall toy scan and provide code/data for reproducibility.

Series context. Paper IV.2 of Gravity as Temporal Geometry (time-first GR).