– The laws of physics are essentially time-symmetric, and they have no concept of causation or of a preferred direction of time. In principle, the future causes the past as much or as little as the past causes the future. Physics effectively only says they have to be consistent with each other, as related by the laws of physics.
– The apparent directionality of time that we perceive is suspected to be tied to the entropy gradient we are on. See the “past hypothesis” for example [0].
> Does this essentially mean that all states in time already exist and our consciousness is just traversing this 4D space in one direction on the time axis?
– I would say that all moments in time are equally real, including our consciousness at any given moment. There is no actual flow or “travelling”. The flow we perceive is merely an illusion caused by the fact that we only remember the past and not the future (which again may just be a consequence of the entropy gradient we are on). This is known as the “block universe”, or as “eternalism” [1]. The opposing view that only the current moment is real, and that the future differs from the past in its “realness”, is known as “presentism”.
– Note that any notion of “travelling” through time implies that you can draw a 2D diagram of where in time you are at each point in time, or which point in time is “real” at which point in time (in the sense that a moment in time isn’t real until time reaches that moment, but after that it is real and cannot be made unreal again), thus implying two dimensions of time. That doesn’t make any sense, and thus my personal conclusion is that the “presentism” view is nonsensical.
– The laws of physics are essentially time-symmetric, and they have no concept of causation or of a preferred direction of time. In principle, the future causes the past as much or as little as the past causes the future. Physics effectively only says they have to be consistent with each other, as related by the laws of physics.
– The apparent directionality of time that we perceive is suspected to be tied to the entropy gradient we are on. See the “past hypothesis” for example [0].
> Does this essentially mean that all states in time already exist and our consciousness is just traversing this 4D space in one direction on the time axis?
– I would say that all moments in time are equally real, including our consciousness at any given moment. There is no actual flow or “travelling”. The flow we perceive is merely an illusion caused by the fact that we only remember the past and not the future (which again may just be a consequence of the entropy gradient we are on). This is known as the “block universe”, or as “eternalism” [1]. The opposing view that only the current moment is real, and that the future differs from the past in its “realness”, is known as “presentism”.
– Note that any notion of “travelling” through time implies that you can draw a 2D diagram of where in time you are at each point in time, or which point in time is “real” at which point in time (in the sense that a moment in time isn’t real until time reaches that moment, but after that it is real and cannot be made unreal again), thus implying two dimensions of time. That doesn’t make any sense, and thus my personal conclusion is that the “presentism” view is nonsensical.
[0] https://en.wikipedia.org/wiki/Past_hypothesis
[1] https://en.wikipedia.org/wiki/Eternalism_(philosophy_of_time...