Jean-Pierre Petit on The geometric origin of the difficulty of talking with dead people

See Le Modèle Cosmologique Janus (2016), also his Janus v. Dark Science Comic. And the Wikipedia entry Boy's Surface for the four-dimensional version. There is also this 2024 paper by Petit, Margnat and Zejli: A bimetric cosmological model based on Andreï Sakharov’s twin universe approach. See also this 2021 paper by Debergh, D’Agostini and Petit: On the Poincaré Algebra in a Complex Space-Time Manifold.

Here's his 10 March, 2025 letter to Sabine Hossenfelder: https://www.jp-petit.org/papers/cosmo/2025-02-10-to-SABINE-HOSSENFELDER.pdf where he says he is doing "Physics west of the Pecos". See Sabine Hossenfelder's (2008) Bimetric theory with exchange symmetry.

I hope Julian Barbour and Neil Turok get to talk to Jean-Pierre Petit before he dies! He has a web site: https://www.jp-petit.org/.

Subscribe to Jean-Pierre Petit. 

How to cultivate intuition:

Subscribe to Academy of Ideas.

See  Toby's 3D model of a "Four-dimensional Penrose Triangle".

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