The whole universe might have started as a tiny, empty donut-shaped hole in nothingness.
March 27, 2026
Original Paper
The Universe Originating from an Empty Planck-Size Torus
arXiv · 2603.24669
The Takeaway
Instead of a Big Bang full of hot radiation, this model suggests the universe started as a 'Planck-size torus' containing absolutely nothing. The 'Casimir energy'—a weird quantum pressure from the vacuum itself—would have been enough to trigger inflation and create the energy density we observe today.
From the abstract
We consider a Universe with a three-torus topology which before inflation is devoid of any matter or radiation. Its pre-inflationary evolution is driven solely by Casimir energies of the existing fields, with a radiation-like equation of state. We show that, quite strikingly, with the appropriate number of fermions and bosons in the theory, such a Universe evolving from Planck size at Planck time has the correct critical energy density today. Moreover, assuming typical parameters for inflation a