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Barbour’s thesis is that the Big Bang, which he calls the Janus Point, seeded the flow of time in two directions. Time “no longer has one direction, from past t

by T-A 5y ago

Barbour’s thesis is that the Big Bang, which he calls the Janus Point, seeded the flow of time in two directions. Time “no longer has one direction, from past to future, but instead has two: from a common past at the Janus point to two futures in the two directions away from it,” Barbour writes. From 2018: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.121.251301 https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.12... https://physicsworld.com/a/our-universe-has-antimatter-partner-on-the-other-side-of-the-big-bang-say-physicists/ https://physicsworld.com/a/our-universe-has-antimatter-partn...

nabla9 5y ago
Sean Carroll has also proposed two headed arrow of time. If the direction of time is towards increasing entropy, the starting point of time is the lowest entropy configuration in the universe. The arrow of time is pointing away from that point. https://www.preposterousuniverse.com/blog/2004/10/27/the-arrow-of-time/ https://www.preposterousuniverse.com/blog/2004/10/27/the-arr... Spontaneous Inflation and the Origin of the Arrow of Time https://arxiv.org/abs/hep-th/0410270 https://arxiv.org/abs/hep-th/0410270 >Sean M. Carroll, Jennifer Chen >We suggest that spontaneous eternal inflation can provide a natural explanation for the thermodynamic arrow of time, and discuss the underlying assumptions and consequences of this view. In the absence of inflation, we argue that systems coupled to gravity usually evolve asymptotically to the vacuum, which is the only natural state in a thermodynamic sense. In the presence of a small positive vacuum energy and an appropriate inflaton field, the de Sitter vacuum is unstable to the spontaneous onset of inflation at a higher energy scale. Starting from de Sitter, inflation can increase the total entropy of the universe without bound, creating universes similar to ours in the process. An important consequence of this picture is that inflation occurs asymptotically both forwards and backwards in time, implying a universe that is (statistically) time-symmetric on ultra-large scales
arthurcolle 5y ago
So Tenet actually may have made sense? After multiple rewatchings I just thought the mechanics were completely nonsensical.

by T-A 5y ago

nabla9 5y ago

Sean Carroll has also proposed two headed arrow of time. If the direction of time is towards increasing entropy, the starting point of time is the lowest entropy configuration in the universe. The arrow of time is pointing away from that point. https://www.preposterousuniverse.com/blog/2004/10/27/the-arrow-of-time/ https://www.preposterousuniverse.com/blog/2004/10/27/the-arr... Spontaneous Inflation and the Origin of the Arrow of Time https://arxiv.org/abs/hep-th/0410270 https://arxiv.org/abs/hep-th/0410270 >Sean M. Carroll, Jennifer Chen >We suggest that spontaneous eternal inflation can provide a natural explanation for the thermodynamic arrow of time, and discuss the underlying assumptions and consequences of this view. In the absence of inflation, we argue that systems coupled to gravity usually evolve asymptotically to the vacuum, which is the only natural state in a thermodynamic sense. In the presence of a small positive vacuum energy and an appropriate inflaton field, the de Sitter vacuum is unstable to the spontaneous onset of inflation at a higher energy scale. Starting from de Sitter, inflation can increase the total entropy of the universe without bound, creating universes similar to ours in the process. An important consequence of this picture is that inflation occurs asymptotically both forwards and backwards in time, implying a universe that is (statistically) time-symmetric on ultra-large scales

arthurcolle 5y ago

So Tenet actually may have made sense? After multiple rewatchings I just thought the mechanics were completely nonsensical.