That’s a brilliant and very profound question — and yes, some theoretical physicists and cosmologists have proposed models where:
Inside a sufficiently massive black hole, there could exist a “baby universe” — potentially with its own Big Bang.
Let me walk you through the idea, step by step:
🌀 1.
The Idea in a Nutshell
In certain speculative theories:
- The interior of a black hole, particularly the singularity, is not the “end” — but instead, a bridge or narrow throat to another region of spacetime.
- That region could expand, evolving into a new universe, with its own space and time — a baby universe.
- From the outside, we just see a black hole. From the inside, it could be a universe experiencing its own Big Bang-like beginning.
🧠 2.
Who Has Proposed This?
Several physicists and cosmologists have explored variations of this concept:
- Lee Smolin’s Cosmological Natural Selection:
- Suggests universes reproduce through black holes.
- Each universe has slightly different physical constants.
- This creates a kind of evolutionary multiverse, where universes that make many black holes leave more “offspring.”
- Nico Popławski’s Torsion-based cosmology:
- In Einstein–Cartan theory (an extension of general relativity with torsion), the collapse of matter in a black hole bounces instead of forming a singularity.
- That bounce initiates an expanding universe on the “other side” — a new Big Bang.
- Popławski even suggests that our universe could be inside a black hole in another universe.
- Roger Penrose (less directly):
- In his Conformal Cyclic Cosmology (CCC), universes succeed one another in an eternal sequence, though not through black holes specifically.
- But the recycling motif resonates with the black-hole-as-cosmos idea.
🌌 3.
Is There Physics Behind It?
Yes, though speculative. Key elements include:
- General relativity allows for Einstein–Rosen bridges (wormholes), which could connect black holes to other spacetime regions.
- In loop quantum gravity, spacetime is quantized and may avoid singularities — instead producing Big Bounces.
- Entropy and information theory play a role, too: if information isn’t lost in a black hole, where does it go? Could it encode a new universe?
🚫 4.
But… Caveats
- These are hypotheses, not established facts.
- We have no direct observational access to what’s inside a black hole’s event horizon.
- Singularities are undefined in general relativity — we need a full theory of quantum gravity.
- There’s no guarantee that conditions inside a black hole would naturally lead to inflation or expansion like in our Big Bang.
🌱 5.
Poetic Possibility
Still, the idea is beautiful:
That the death of matter in one cosmos could seed the birth of another.
That the collapse of space in one frame is the unfolding of time in another.
That perhaps, in the heart of darkness, there always lies a next beginning.
Would you like a comparison between this idea and other cosmological models, like eternal inflation or ekpyrotic universe scenarios? Or maybe a fictional dialogue between a dying star and its unborn universe?
