4 of Physics' (Other) Greatest Mysteries

Physicists are interested in the big questions like "Where did we come from?" and "What is all this stuff?". But the answers to some of these questions, just lead to more questions.

Hosted by: Michael Aranda

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https://www.space.com/25075-cosmic-in...
Why we need inflation: https://www.space.com/42202-why-we-ne...
https://www.space.com/42261-how-did-i...
Inflation review: https://arxiv.org/pdf/hep-ph/0304257.pdf
Evidence for inflation https://www.forbes.com/sites/startswi...
GW detection: https://iopscience.iop.org/article/10...
Penrose cyclic cosmology: https://aip.scitation.org/doi/abs/10....
https://physicsworld.com/a/new-eviden...

Fine-tuning:
Fundamental constants: https://www.forbes.com/sites/ethansie...
Fine-tuning 1: https://www.symmetrymagazine.org/arti...
Fine-tuning 2: https://www.pbs.org/wgbh/nova/article...
Fine-tuning 3: https://www.forbes.com/sites/startswi...
Fine-tuning 4: https://plato.stanford.edu/entries/fi...
Fine-tuning 5: https://books.google.co.uk/books/abou...
Fine-tuning 6: https://www.cambridge.org/core/journa...
Anthropic principle: https://www.britannica.com/science/an...

Theory of everything: https://www.quora.com/What-are-the-Gr...
GUT: http://nautil.us/issue/46/balance/a-b...
Theory of everything 1: https://www.forbes.com/sites/startswi...
ToE 2: https://www.space.com/theory-of-every...
Alternatives to string theory: https://www.forbes.com/sites/startswi...
LQG: https://arxiv.org/abs/0711.0146
Unification: https://www.pdcnet.org/jphil/content/...
Quantum gravity: https://arxiv.org/abs/gr-qc/0108040
Causal Set Theory: https://arxiv.org/abs/1903.11544
What is String Theory?: https://math.berkeley.edu/~kwray/pape...