Jul 23, 2025 09:50 PM
(This post was last modified: Jul 24, 2025 07:08 AM by C C.)
The Universe is not the same forward and backward in time
https://bigthink.com/starts-with-a-bang/...symmetric/
KEY POINTS: One of the surprising facts about many of the laws of physics is that they’re time-reversal-invariant (T-symmetric), meaning that particles follow the same rules whether you run the clock forward or backward. But there are certain symmetries that are shown to be violated, like replacing particles with antiparticles (C-symmetry) or replacing particles with their mirror images (P-symmetry). Since the combination of C, P, and T symmetries (CPT symmetry) must be conserved, violating CP implies that T symmetry must be violated, too. Here’s how we finally showed that really is the case... (MORE - details)
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COMMENT: But if time is instead crudely, figuratively akin to motion picture film (wherein all differences co-exist) and the specious "flow" only seems to occur on the projection screen (barbarically equivalent to consciousness)... Then, if the latter subjective arrow reversed, there would not be a modification of the content in the frames constituting the film.
Plus, when your cognitive orientation returned to the "forward" direction again, you would not remember that you had been experiencing the world backwards. Any more than the characters in a movie remark about a reversal having occurred. Whether the arrow is forwards or backwards, the possibility expressed in the article above is based on the metaphysical belief that each current state of the world is being constantly replaced (annihilated) by a newly created one (past and future don't exist).
Long before either Minkowski space or general relativity, and instead playing off the precursor constructs of 19th-century mathematicians, who first envisioned of time as conforming to four dimensional structure, this was conceived as the origin of the "flow":
H.G. Wells (1895): “Clearly,” the Time Traveller proceeded, “any real body must have extension in four directions: it must have Length, Breadth, Thickness, and—Duration. But through a natural infirmity of the flesh, which I will explain to you in a moment, we incline to overlook this fact. There are really four dimensions, three which we call the three planes of Space, and a fourth, Time. There is, however, a tendency to draw an unreal distinction between the former three dimensions and the latter, because it happens that our consciousness moves intermittently in one direction along the latter from the beginning to the end of our lives." --The Time Machine
https://bigthink.com/starts-with-a-bang/...symmetric/
KEY POINTS: One of the surprising facts about many of the laws of physics is that they’re time-reversal-invariant (T-symmetric), meaning that particles follow the same rules whether you run the clock forward or backward. But there are certain symmetries that are shown to be violated, like replacing particles with antiparticles (C-symmetry) or replacing particles with their mirror images (P-symmetry). Since the combination of C, P, and T symmetries (CPT symmetry) must be conserved, violating CP implies that T symmetry must be violated, too. Here’s how we finally showed that really is the case... (MORE - details)
- - - - - - - - - - - - - - - -
COMMENT: But if time is instead crudely, figuratively akin to motion picture film (wherein all differences co-exist) and the specious "flow" only seems to occur on the projection screen (barbarically equivalent to consciousness)... Then, if the latter subjective arrow reversed, there would not be a modification of the content in the frames constituting the film.
Plus, when your cognitive orientation returned to the "forward" direction again, you would not remember that you had been experiencing the world backwards. Any more than the characters in a movie remark about a reversal having occurred. Whether the arrow is forwards or backwards, the possibility expressed in the article above is based on the metaphysical belief that each current state of the world is being constantly replaced (annihilated) by a newly created one (past and future don't exist).
Long before either Minkowski space or general relativity, and instead playing off the precursor constructs of 19th-century mathematicians, who first envisioned of time as conforming to four dimensional structure, this was conceived as the origin of the "flow":
H.G. Wells (1895): “Clearly,” the Time Traveller proceeded, “any real body must have extension in four directions: it must have Length, Breadth, Thickness, and—Duration. But through a natural infirmity of the flesh, which I will explain to you in a moment, we incline to overlook this fact. There are really four dimensions, three which we call the three planes of Space, and a fourth, Time. There is, however, a tendency to draw an unreal distinction between the former three dimensions and the latter, because it happens that our consciousness moves intermittently in one direction along the latter from the beginning to the end of our lives." --The Time Machine