# The Cosmological Constant Problem (1/2)

- Institution: CERN
- Department: Academic Training Lecture Regular Programme,2015-2016
- Speaker: Antonio Padilla
- Year: 2015
- Level: Graduate
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3017678)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

I will review the cosmological constant problem as a serious challenge to our notion of naturalness in Physics. Weinberg's no go theorem is worked through in detail. I review a number of proposals possibly including Linde's universe multiplication, Coleman's wormholes, the fat graviton, and SLED, to name a few. Large distance modifications of gravity are also discussed, with causality considerations pointing towards a global modification as being the most sensible option. The global nature of the cosmological constant problem is also emphasized, and as a result, the sequestering scenario is reviewed in some detail, demonstrating the cancellation of the Standard Model vacuum energy through a global modification of General Relativity..

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## Lectures

1. [The Cosmological Constant Problem (1/2)](https://invisiblenetwork.ai/learn/cern/3017678/d0fdac01654d), 1 h 29 min (CERN's player)