Many people argue that time travel cannot ever exist, because if they went back in time and somehow destroyed the history which enabled them, they couldn't exist to do it.But if they don't exist, then they couldn't have prevented their history, so the world would go on just as it had until that person goes back in time, then it would all start again from the same point in time.We would never know because we would be a time loop until that person grows up, goes back in time, an has never existed again.I am not claiming time travel will be possible, I am only claiming if it became possible we would never know about it before it became possible.

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ah yes, the grandfather effect, it's a mind bender.like you pointed out, if you went back and killed your grandad you would never exist, if you never existed you would not kill ya grandad, then you would exist and so begins the eternal time loop, nananana nananana nananana.best thing is you could go back with a few AKs and rule the world and in the process of raining the world you accidental off'd an ancestor no prob, just start again, but say you killed Mikael Kalashnikov ancestor, would the AKs disappear from you hand?if so they never existed and you would not have killed the geezer, so they would exist and reappear.MY HEAD HURTS!!!

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Think about time if time travel exsists which im not ruling out there would already be time travelers here. and I'm sure they would not speak up if so.

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Well this scenario assumes that one person only invented time travel and then went back in time to prevent their own existence. If that happened in that way, the world would indeed never know. A more likely scenario is that the time traveler does not mess up his own history but distorts the past in other ways. That may or may not affect the knowledge of or capacity to time travel from the present. And of course all of this assumes there is one and only one time line. Who's to say that every alternate reality does not exist? If so, then a time traveler might not affect their own time line, but merely create a new, parallel one from any 'changes' they make when visiting the past.

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time is an illusionary projection of the mind, a construct to contextualise experience as life.within this illusion, we are all time travellers. I spent this morning in the past, I plan to be in the future this evening.the illusory nature of time is betrayed by these paradoxes; the mind cannot resolve these ideas, and thus betrays it's own illusory dominion.past and future are only ideas. they are never experienced, except as concepts, and these concepts can only arise in the present, now.Now is all there ever is. This is the eternal, before and after the illusion of time. The eternal says; I am the alpha and the omega.of course, time is useful out here in the hologram. As a very wise man said to me once; I don't want my starter and my pudding on the same plate ...

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Rather than dwell on a paradox, its best to first contemplate if the grounds of the paradox are even plausible. The concept of time travel violates the first law of thermodynamics. I can give you a list of paradox situations that lack any basis in reality. They are fun to contemplate, but if they lack any basis in reality then it is nothing but an endeavor in futility.

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This question has, at its core, some sharp realisation of personal sense of uniqueness, or a realisation that the flow of events in life need to be observed, checked and ultimately managed by a single and individualistic command of will. Do you realise that the thought of travelling through time inculcates in the mind a subtle but powerful sense of isolation? For when one is able to travel through time the rest of the world is imagined as being traversed the way a lone traveller would traverse through vast expanses of land, or sea, lying passively in its footsteps ... and if this is an exaggeration of the matter of the your quesiton, then so is the concept that defies time, the nature of matter.If I, for instance, travel through time then all the world would change around me, backward or forward, with me staying constant in the mean time, meaning that time in the compartment of my being would run normally, it would stay suspended and stationary, while the rest of the train, the world, would move forward.Whereas, the fact about time is that it does not have any materialistic existence of its own, it is an effect we observe. It is the change in all things around us, a manifestation of the most obvious, and therefore easily overlooked, characteristic of matter. As all material things change, and unpredictable change is at the heart of each atom of the matter. Then time is the change we observe around us, and within us, only relatively. For instance, if I sit in a running car and observe another car running parallel, I would be able to see the passengers of that car as if that car were standing next to mine in a car park. Time is not something that we could travel within. However, considering the common use of the phrase ‘time travel’, it might be possible to reverse time only if all the direction of change in the matter is mastered, all the electrons are made to go in reverse or forward at will, or by a method – we cannot change characteristics of something without modifying the thing itself first. The concept of time travel in the mind is made possible by imagination, and it is an expression of our innate wish to explore this world, to pass trough it freely and to manage it preferably single-handedly. Whereas, no man on his own is strong enough to do just that, to be able to stand aloof and watch the world go by, as if it were a stream of traffic on the road in front!http://uk.blog.360.yahoo.com/blog-_f...4&yy=2006&mm=9

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Existence has been stated by the sages "over time" is in the very moment.The very moment of the moment is where a person exists not the future and not the past.The past is set.IF - a traveler changes an item of the past it is no longer the past but a possible past.There is not a loop because "this/that past" no longer exists only a possible past.Then - too - memory of an "alternate" past is "erased". The mind may imagine a different past but it still does not exist.

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There is no such thing as time travel.And the reason for this is because time is not a dimension."WHAT?!"Yes, that's true. Time is not a dimension."But they said spacetime and..."No, they're wrong. There is only space.Time is ONLY a Measurement.A measurement of what? A measurement of change.That's all.Time is a measurement of change. This is why two 40 year old women could appear as mother and daughter though they have the same earthly calendar age measured by revolutions of the earth around the sun. 40 sun revolutions but these two women look like mother and daughter and why?Because their biological patterns of change are different.One looks closer to 55 and the other looks closer to 30. Habits you have and things you undertake make you "age" differently too.I know someone about to be 50 but could pass for her 30's or early 40's at most. I knew another one around 50 who looked like closer to 60 to me.You wanna go back in time? Simple. Take a clock and set it at an earlier hour. Take a wind-up clock and just wind the opposite way. Congratulations you've gone back in time.Time does not exist as a dimension as in like we see VCR tapes & DVD's which can be rewound and reviewed. It is simply a measurement of change that without constant patterns of objects in the universe could never exist.We have a constant or constant enough as far as we can see Sun and Moon pattern. This is the only reason we were able to create a measurement of time in the first place. Sundial? Moon phases to mark the months? Lunar calendars? The slow evolution of weather seasons when days and night periods change? But only in certain parts of the world that don't include the poles where a day can last a calendar 6 months and a night another 6?All other clocks and time measurement devices built upon these early measurements of time by mankind. We refined them and elaborated on them but it's still based off the same thing.It is mankind's way of documenting change which can be random and unpredictable at "times".You can undo change if you know how but that doesn't mean you can undo things done at a certain time. When it's done it's done. You can medically fix a scar gained in your past, the measurements of time before your current standing. But you cannot go back from your current measurement in time to prevent that scar from occuring in the first place. That is impossible. Time only means it has been, say, 8 months since you gained that scar and nothing more. It measures the amount of change that biologically and socially happened since obtaining that scar. Your body heals and the scar's look changes. Your job may have changed since getting that scar and your life may be different since getting scarred. But it's just change of circumstances. You can't reverse or prevent what was already done. All you can do is fix it in the now if possible.Time travel doesn't exist because the premise is faulty to begin with. It assumes time is a dimension like point, line, and shape which makes space when it is only a mere measurement of change from one aspect to another.If I want to "go back in time" to June all I have to do is flip the calendar back one page from its current July setting. Voilá! I've gone back in time.John Lucas

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