In this video I talk about some proposals for REALLY big experiments that physicists have put forward and what we could do with them. Besides the Future Circular Collier, the Collider in the Sea, a radio telescope or neutrino source on the moon, or a gravitational wave interferometer the size of the solar system. The mentioned references are: BBC Interview with quote from King: https://www.bbc.com/news/science-environment-46862486 Collider in the Sea: https://accelconf.web.cern.ch/napac2016/papers/mob2co03.pdf The Gizmodo article with the Beachman interview: https://gizmodo.com/we-could-solve-the-mysteries-of-time-and-space-if-we-ha-1829207595 Radio telescope on the Moon: https://www.nature.com/articles/d41586-017-08941-8 Neutrino-Source on the Moon: https://arxiv.org/abs/2002.12190 Gravitational Wave Interferometer on the Moon: https://arxiv.org/abs/2007.08550 Gravitational Wave interferometer from atomic clocks: https://arxiv.org/abs/1501.00996