MuadDib

Assuming you can travel backwards in time, there are three ways you can view temporality. Either (a) time is predicated through causality, call this the fatalist perspective, (b) time is linear and now is the focal point of the temporal dimension, call this the linear perspective, or (c) time is non-linear and subjective to the perceiver, call this the non-linear perseptive.

Under the fatalist perspective the grandfather paradox is simply not possible. Even if you travelled back in time to kill your grandfather you simply could not do it. If you killed anyone they could not be your grandfather. Because the universe is purely causal, the entire course of history was set an conception and has headed down a predictable path based on the laws of science. Essentially, your time travel is part of the plan and anything you do in the past was done in your present rather you were aware of the design or not. This is like the Futurama scenario where they WERE the aliens at Roswell, always were, and they were thus a part of their own history and their time travel was predetermined.

Under the linear perspective, you have more of a Back To The Future style scenario. Under this point of view you could kill your grandfather and the results could vary. Either you could create a paradox and time would perpetually loop with you killing your grandfather, then not existing to kill him and thus existing, and so on, or you might go on existing nonetheless in some sort of temporal fail-safe because contradictions such as this simply cannot occur in nature rather we can comprehend the fail-safe or not.

The non-linear perspective is the one I subscribe to. The fatalist POV just leaves a bad taste in my mouth as someone who both believes in some form of free will and someone who is not absolutely convinced by a causal explanation to the universe simply because its easy, observable, and traditional. I also have a problem with the linear perspective because it just seems terribly egocentric. Just because I am solely familiar with my unique consciousness and perspective does not mean that I am the exclusive consciousness and persepctive. Thus the now I am experiencing is not the only now. Your now is an equally valid now, but so is the now of the atomic clock travelling at supersonic speeds that arrives with an earlier time as an identical atomic clock waiting for the jet to circle the globe. Consequently, were I to travel back in time, everyone experiencing that now (my grandfather and everyone else at that meeting in time) is also experiencing now. They are not in the past nor am I. We are all sharing a now, or our present. Under this view I could kill my grandfather without temporal reprecussion because I did not kill him in the "past", I killed him in the "present". Essentially, this view would hold that, though we perceive time as one moment after the next, all time is really existing in the now and is all happening at once. There would be no causal implication to dicking with the past because there is no causation it all just happens/happened/is happening. We simply just can't perceive time in this manner so we are perceive it linearly.

Anyway, I think this exhausts the possibilities. Luckily in only one potential result from one possible reality does a paradox occur and lead to problems for the universe. So purely statistically, odds are we are gonna be alright.

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"The courts that first rode the warhorse of virtual representation into battle on the res judicata front invested their steed with near-magical properties." ~27 F.3d 751