Before the Big Bang

[DaveC426913]

I do not know if this has been brought out. There is this theory of Janus universes (as in Janus the god with two heads). Where basically from point $t=0$, going forward in time gives a universe and rewinding back gives another universe. Similar to putting many gas particles in the corner of a box, you go forward in time the gas fills the box, you inverse the speed of all particles, the gas fills the box too.

This sounds a lot like the Big Bounce.

 

[javisot]

This sounds a lot like the Big Bounce.

I understand that he is referring to,
https://arxiv.org/abs/2208.10396
https://arxiv.org/abs/gr-qc/0505116
https://arxiv.org/abs/2511.11109