Chapter 02 · The Origin of Our Universe
The Origin of Our Universe
How did our universe begin?
The Big Bang is the consensus framework, but many Chapter 1 families also answer this question, what triggered our universe, given what existed before it? Bridge variants are surfaced here from their parent families in Chapter 1.
Families (6)
- ConsensusStandard Big BangOur universe emerged ~13.8 billion years ago from an extraordinarily hot, dense state.1 variant1 vote
- Strongly supportedInflationary Big BangA brief epoch of exponential expansion prepended to the hot Big Bang, solving horizon, flatness, and monopole problems.3 variants
- FrontierCPT-Symmetric UniverseThe Big Bang is a symmetric mirror point; our universe pairs with an antimatter universe running backwards in time.1 variant
- FringePlasma CosmologyElectromagnetic forces and plasma physics, not gravity, dominate cosmic structure formation. There may be no Big Bang at all.3 variants
- HistoricalTired LightPhotons lose energy as they travel through space; cosmological redshift is not from expansion.2 variants
- HistoricalSteady StateThe universe has always existed and always will, with new matter created continuously to keep the average density constant despite expansion.2 variants
Bridged from other chapters
These variants live in their own chapters but also answer this chapter's question.
Ch.01Quantum Vacuum MechanismSpeculative
Coleman-De Luccia
False vacuum decay with gravity. The standard mechanism for bubble nucleation.
→
Ch.01Quantum Tunneling OriginSpeculative
Vilenkin's Tunneling from Nothing
The universe quantum-tunneled from literal nothing, no space, no time, no fields.
→
Ch.01Eternal InflationStrongly supported
Linde's Chaotic Eternal Inflation
Once inflation starts, it never stops everywhere, generating a self-reproducing multiverse.
→
Ch.01Cosmological SelectionSpeculative
Smolin's Cosmological Natural Selection
Universes evolve by natural selection. Black holes are reproductive events, and our universe is descended from ancestors that were good at making black holes.
→
Ch.01Cyclic & Bouncing CosmologiesSpeculative
Loop Quantum Big Bounce
Quantum geometry prevents the singularity. Our Bang is the bounce of a contracting predecessor.
→
Ch.01Black Hole GenesisFrontier
Afshordi's Holographic Big Bang
A four-dimensional star collapsed in a five-dimensional bulk, throwing off a three-dimensional membrane that became our expanding universe.
→
Ch.01Cyclic & Bouncing CosmologiesSpeculative
Ekpyrotic Cyclic Universe
Two parallel branes collide periodically, each collision is a Big Bang.
→
Ch.01Black Hole GenesisFrontier
Delayed Phase Transition Baby Universe
Our universe may be a baby universe formed inside a primordial black hole during a delayed first-order phase transition.
→