💥 Black holes could spontaneously arise from a crystallization of spacetime

Microscopic black holes could arise from a crystallization of the fabric of spacetime. This idea comes from researchers who have mathematically described how spacetime can reorganize into regular patterns to generate these objects.

Einstein's theory of general relativity teaches us that mass curves spacetime. Massive objects like stars create a strong curvature, but even small masses influence this structure. In the earliest moments after the Big Bang, density fluctuations could have triggered a sudden transformation of spacetime, causing it to "crystallize" into a periodic structure, somewhat like liquid water turning into ice.


When supercooled water is disturbed, it solidifies instantly. Similarly, a tiny energy perturbation in a spacetime close to its crystallization point can trigger a critical collapse. The researchers compare this process to a minuscule nudge that causes a colossal change, without requiring stellar energy or cataclysmic mergers.

The black holes thus formed would be very small, with a mass comparable to that of an asteroid. But unlike their larger cousins, they would be extremely hot and would rapidly lose energy through Hawking radiation, evaporating almost immediately. This rapid evaporation would make them difficult to detect, but their existence could explain certain cosmic mysteries, such as that of dark matter.

A big surprise for the research team was the simplicity of the equations describing this spacetime crystal. While previous numerical simulations required thousands of hours of computation, their solutions on paper fit in just a few lines, using only elementary mathematical functions. This result, published in the journal Physical Review Letters, opens a new path for understanding black hole formation.

These black holes, if they exist, would be relics of the Big Bang. Their discovery would be a major breakthrough, but even without it, the study of critical collapse remains valuable. It allows us to probe the limits of general relativity and explore strange behaviors of spacetime, such as the transition from a crystalline state to a black hole.

Next step for scientists: to verify their conjectures about the behavior of these spacetime crystals. This work demonstrates that with a bit of imagination and mathematics, one can unveil phenomena as strange as they are elegant, without even leaving the comfort of a sheet of paper.

Spacetime crystal: an analogy with ice

A crystal is a solid whose atoms are arranged in a regular and periodic manner. In a spacetime crystal, it is the framework itself that acquires a repeating structure. Ordinary three-dimensional space could undulate according to a pattern that repeats in time. This resembles a network of lines and points that organize the geometry of the Universe.

This idea is inspired by condensed matter physics, where sudden phase transitions occur. Supercooled water is an example: it remains liquid below freezing, but a simple vibration turns it into ice. Similarly, spacetime could be in a metastable state, ready to crystallize under the effect of a tiny perturbation.

Unlike ordinary crystals, a spacetime crystal is not made of matter, but of the very structure of the cosmos. Its existence would have profound consequences on our understanding of gravity and the earliest moments of the Universe. Mathematics reveals that such objects are exact solutions of Einstein's equations, even if their physical reality remains to be proven.

Critical collapse: a cosmic tipping point

Critical collapse is a phenomenon where a system reaches precisely the threshold necessary to form a black hole.

In the case of spacetime crystals, critical collapse occurs when the periodic structure destabilizes. Either it disperses into radiation, or it contracts into a tiny black hole. This process is extremely sensitive: an infinitesimal variation in injected energy can change the fate of the system.

This mechanism does not require stellar mass. It could have occurred just after the Big Bang, when the Universe was dense and hot. Black holes created this way would be primordial and could constitute a fraction of dark matter. Their existence remains hypothetical, but their study refines our understanding of gravitational phase transitions.