Did the universe really start with a massive explosion out of nothing? What if everything you were taught about the Big Bang in school is fundamentally wrong?Join Jeroen Schreel and Niayesh Afshordi, a Professor of physics and astronomy at the University of Waterloo, and research associate faculty at Perimeter Institute as they deconstruct the modern definition of the Big Bang, shifting away from the idea of a mathematical "singularity" where time stops, and looking at it like waking up from a cosmic dream. From cosmic inflation and primordial sound waves to mind-bending alternative models, like a cyclical "Big Bounce" or the hypothesis that our 3D reality emerged from a collapsing 5D star, this episode bridges the gap between popular myth and cutting-edge physics.

(00:00) Intro

(00:39) Ad

(02:44) Re-defining the Big Bang

(06:09) The Hawking & Penrose Singularity: Where the math of standard physics hits a limit

(07:54) Waking up from a cosmic dream: The modern scientific definition of our origins

(14:10) Archeology of the sky: Reading cosmic microwave background radiation and sound waves

(22:50) What is Cosmic Inflation? Solving the horizon problem

(35:33) The Varying Speed of Light theory vs. Inflation models

(36:30) Bouncing Narratives: Are we living in a cyclical universe?

(37:45) The 5D Star Hypothesis: Did our universe emerge from a higher-dimensional black hole?

(46:50) The Eternal Inflation Multiverse & String Theory: Elegance vs. testability

(57:50) The Copenhagen Survey: Testing what world-class physicists actually believe

(01:03:15) Changing your mind in physics: Why science makes progress "one funeral at a time"

Papers recommended by Niayesh:- Hu and Dodelson, 2002. Cosmic Microwave Background Anisotropies. Annual Review of Astronomy and Astrophysics, 40: pp. 171-216; https://doi.org/10.1146/annurev.astro.40.060401.093926- Guth, 1981. Inflationary universe: A possible solution to the horizon and flatness problems. Physical Review D, 23: pp. 347-356; https://doi.org/10.1103/PhysRevD.23.347- Akrami et al., 2019. Planck 2018 results - X. Constraints on inflation. Astronomy & Astrophysics, 641: Article A10; https://doi.org/10.1051/0004-6361/201833887- Borde et al., 2003. Inflationary Spacetimes Are Incomplete in Past Directions. Physical Review Letters, 90: Article 151301; https://doi.org/10.1103/PhysRevLett.90.151301- Albrecht and Magueijo, 1999. Time varying speed of light as a solution to cosmological puzzles. Physical Review D, 59: Article 043516; https://doi.org/10.1103/PhysRevD.59.043516- Brandenberger and Peter, 2017. Bouncing Cosmologies: Progress and Problems. Foundations of Physics, 47: pp. 797-850; https://doi.org/10.1007/s10701-016-0057-0- Pourhasan et al., 2014. Out of the white hole: a holographic origin for the Big Bang. Journal of Cosmology and Astroparticle Physics, 2014: Article 1309.1487; http://dx.doi.org/10.1088/1475-7516/2014/04/005- Guth, 2007. Eternal inflation and its implications. Journal of Physics A: Mathematical and Theoretical, 40: Article 6811; https://doi.org/10.1088/1751-8113/40/25/S25- Chen et al., 2025. Copenhagen Survey on Black Holes and Fundamental Physics. Preprint; https://doi.org/10.48550/arXiv.2503.15776- Afshordi et al., 2026. Big Mysteries Survey: Physicists' Views on Cosmology, Black Holes, Quantum Mechanics, and Quantum Gravity. Preprint; https://doi.org/10.48550/arXiv.2605.11058

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