# Three Impossible Theories

@inproceedings{Susskind2021ThreeIT, title={Three Impossible Theories}, author={Leonard Susskind}, year={2021} }

I will begin by conjecturing a cosmological generalization of black hole complementarity (also known as the central dogma). I will then discuss three theories and argue that they are inconsistent with second law of thermodynamics if the cosmological version of the dogma is correct. The three theories are: the big rip; cyclic cosmology; and the Farhi-Guth-Guven mechanism for creating inflating universes behind black hole horizons. ar X iv :2 10 7. 11 68 8v 1 [ he pth ] 2 4 Ju l 2 02 1

#### 3 Citations

A Mechanism of Baryogenesis for Causal Fermion Systems

- Physics, Mathematics
- 2021

It is shown that the theory of causal fermion systems gives rise to a novel mechanism of baryogenesis. This mechanism is worked out computationally in globally hyperbolic spacetimes in a way which… Expand

The Grand Canonical Multiverse and the Small Cosmological Constant

- Physics
- 2021

We consider the Multiverse as an ensemble of universes. Using standard statistical physics analysis we get that the Cosmological Constant (CC) is exponentially small. The small and finite CC is… Expand

A Tail of Eternal Inflation

- Physics
- 2021

Non-trivial inflaton self-interactions can yield calculable signatures of primordial nonGaussianity that are measurable in cosmic surveys. Surprisingly, we find that the phase transition to slow-roll… Expand

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