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arXiv · 1903.11676

Dark Energy, $H_0$ and Weak Gravity Conjecture

Nemanja Kaloper
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Abstract

We point out that the physics at the extreme IR---cosmology---might provide tests of the physics of the extreme UV---the Weak Gravity Conjecture. The current discrepancies in the determination of $H_0$ may hint at a modification of $\Lambda$CDM. An extension which may fit better comprises of an early contribution to dark energy which `decays' into relativistic matter. On the other hand the discourse on WGC to date suggests that fields which support cosmic acceleration may produce relativistic matter after they traverse a $\sim$ Planckian distance in field space. We explain how this offers a simple realization of the requisite cosmic phenomenology. Thus if the resolution of $H_0$ discrepancies is really early dark energy that ends with a shower of relativistic matter and the current ideas on WGC are indicative, this may be a rare opportunity to link the two extreme limits of quantum field theory.

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Nemanja Kaloper. 2019-03-27. Dark Energy, $H_0$ and Weak Gravity Conjecture. https://doi.org/10.1142/s0218271819440176

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