After having read through the initial topic and the responses here is my perspective. Instead of using a lot of quoting and responding, which will be time consuming; I have chosen to write my response in an essay format. The essay will initially explore time travel theories and then express my personal interpretation of time travel in the Harry Potter Books. I will be addressing all the major concerns raised in the first post of this topic in different parts of the essay. If after reading you feel a point is not addressed or something is unclear please do ask.
Time travel as we all know is not yet reality. It is a hypothetical concept. Considering time travels hypothetical nature every proponent of a time travel theory has a different premise and hypothesis, a different explanation no two hypothesis is the same. Since time travel is a complex matter time travel there will always be unexplained factors, contradictions, and holes in every theory. It is all based on what if assumptions nothing is hard and fast.
Before we delve into the philosophy of time travel, we need to know what time travel is and the theories explaining time travel.
What is Time Travel? Time travel is based on the theory that there are more than the three known dimensions of matter. Spatial dimension of space can be a fourth dimension, objects exist in space and can move from one space to another. Spatial travel would be like teleporting from one spatial existence to another, for example teleporting from your living room to the bedroom. Time travel considers time as another dimension. Matter exists in time, while we are aware and exist in now time is constantly moving. Matter was there in the past, matter will be there in future. Moving matter from now to an arrangement of matter in the future is time travel.
What Happens in Time Travel? In teleporting energy moves matter from one place to another. In time travel energy moves matter from one point in time to another.
Can time travel change the past? Considering that we cannot actually travel in time we assume base the repercussions of time travel on assumptions. Not only is time travel a metaphysical concept, it is a spiritual and philosophical concept.
The answer to the question is a yes and no. There is a notion of destiny and preconception, somethings cannot be changed. For example in Xena: Warrior Princess in the episode 'When Fates Collide' Julius Caesar has the Fates change reality so that Xena never meets Gabrielle and is his Queen to prevent his assassination. However, despite the alternate reality Xena and Gabrielle meet by different means and Caesar is ultimately assassinated.
While time travel may be able to change aspects of history, there is a destiny of life and death and somethings that were meant to be. If not one way, by another way what is meant to be will be.
So what happens when the past is changed? The repercussions of time travel can have disastrous consequences. History is filled with events, changing or altering one event mildly can lead to a desirable outcome in a small way. However, there are certain keystone events if changed can lead to a chain reaction of events that changes everything altogether.
The most common theory is that when a certain event is changed an alternate time tangent is created. Something like the following. Each keystone event changed causes multiple tangents.
However, remember that matter and energy are finite. Matter cannot exist two places at once. Which is why any time tangent is considered unstable as it metaphysically splits matter to exist on two separate time lines, the original and the alternate. Some theories state that destiny takes control rearranging events to return the timeline back to the normal time line.
Another theory states that the unstable tangent eventually collapses. An unstable tangent collapses into a black hole destroying everything associated with it. Black holes as we know are unexplained phenomenon in space. Or it could become a wormhole, which is a flaw in the time line continuum linking two points in time through a passageway.
Others state that time itself is multidimensional and there exists a series of time lines and tangents all interconnected in a closeley woven web and when you time travel you move through these tangents and these preexistences. This theory is a lot more complex.
What about changing the future? Some theorists state that the future is yet to occur which means it does not exist so you cannot travel to the future. On the other hand we can travel in the past, and to the past we are the future. So we are similarly the past of a forthcoming future, hence we can move into the future.
Changing the future is similar to changing the past in someways. If you discover an event in the future, make a not about it and return to the present and try to prevent that event from occurring - if it is a minor event there will be minor repercussions. However, if you change a keystone event you create a tangent that depending on the various tangent theories has different outcomes.
Free Will or Destiny? When dealing with the destiny related outcomes of time travel an interesting question is raised. Do we not have free will? If everything is written in destiny then is not life futile?
Some theorists focus on destiny, others on free will - others combine both. Life and death are destiny and cannot be prevented, however how they occur can probably be altered. However, we still have the free will to make changes to alter certain aspects of destiny.
These theorists would say that in essence Caesar could not have prevented his death, but could have prevented his assassination to die in another manner at a later date. However, to do so free will must be engaged efficiently to change the correct alternatives.
Paradoxes! Time travel is full of paradoxes that are inexplicable. They create loops that are irrational objects that are theoretically probable but practically impossible like a Klein Bottle, Perpetual Motion or a Supertask.
For example if someone traveled back to time and killed themselves as a child. That means they were dead as a child. That means they never grew up. They never grew up means they never traveled back in time. If they never traveled back in time then they could not kill themselves. If they did not kill themselves they exist. If they exist they grew up. If they grew up they time traveled. If they time traveled then they killed themselves.
It is an irrational loop. It goes on and on to no end without conclusive outcome. Some people theorize that committing an act that leads to a causal loop can be so disastrous that the entire universe and every bit of existence can crash.
If someone traveled to the future and accidentally killed themselves, there are two outcomes they want to prevent or not. If they do not then they will eventually be an unsolved murder mystery.
If they know they killed themselves and try to prevent it. They know they time traveled in the future and killed themselves. They will prevent the time travel. If they never time traveled they never killed themselves. If they never killed themselves they never tried to prevent it. If they never tried to prevent it they will time travel to the future. If they time travel to the future they will kill themselves.
Another irrational loop.
However, there is also a theory called time line protection hypothesis where the changes occur slowly and allow a person time to rectify that mistake. For example in Back to the Future when Marty McFly changes his parents meeting, his family is slowly disappearing so he has time to fix everything. It changes a causal loop to a temporal loop.
Temporal Loop! A temporal choice loop is when the time traveler causes intentional events in a miniature controlled loop of sorts.
Whoops I forgot my homework. I open my book and find its mysteriously done. After class I go back in time and do my homework and return back to the exact point, I left.
Limits of Time Travel Whether time travel is limited to ones own history or anypoint in history is another matter of debate. Some theorists state that since we do not exist beyond our history it is impossible. However, if you time travel to a point in history before you were born, then you existed those moments because of your time travel. It is part of your history and you can go there. So time travel is really limitless, you can go to any point in time.
Moving onto my perception of time travel in the Harry Potter world. Just like our world time travel in the wizarding world is quite a delicate subject matter. While the technology and ability exists, it is quite a forbidden art due to the disastrous consequences. Time travel can be used for minor gain like Hermoine time traveling to take extra classes. However, it cannot literally change the past. They cannot time travel to save Sirius or prevent Voldemort from killing Harry's Parents as it was inevitable death.
However, Buckbeak could be saved as he was not really killed, a temporal loop was created before his death to prevent it.When McGonagall said that wizards had killed their past or future selves, I think the outcome was slow enough that the event could be rectified. Since the event was rectified the past really was not changed at all. These are both paradoxical in many ways but form the best plausible explanation for two conflicting time line occurrences in the books.
With the whole instance with Harry fighting the dementors. Harry is fighting the dementors and faints after seeing a familiar face casting a patronus. He believes it to be his father. After his fainting Snape finds him and takes him to the hospital wing. In the hospital wing he learns that dead cannot come back, and also Hermoine's time turner. He deduces logically that it was he who cast the patronus. He uses the time turner to go back in time casts the patronus. He is able to cast it because he knows he saw himself do it. Harry sending the Patronus feels no pain as he is matter from the future existing in the present for the brief period of time. Considering that they are two seperate forms of matter existing in the same point of time what effects one matter does not affect the other. So that is why Harry is unaffected by the pain and can go resuce Sirius.
Below is a diagram illustrating the situation. The Black square is Harry. In the future Harry creates a temporal loop to go back in time do the deeds. The time turner is set so that Harry reappears, the exact second Harry moves to the past so that in that point of time Harry is just one, he reappeared the second he disappeared in time.However, in the past there are two Harrys independent of each other.
Hermoine does not create parallel worlds as to create a parallel world she needs to change a key event. What Hermoine is merely doing is being in two classes at once, without effecting anything else. It is like me sitting in my room reading a book, while sitting in the hall watching TV. Both unknown to each other unaffecting each other. Hermoine takes class A, when she is done with it she turns time to go back in time and sits in Class B. Result is that for that one period there is Hermoine sitting in two classes. When she is done with class B she returns to the exact point in the future where she went back, so it seems like she never left. See below for Hermoine's loop. Hermoine is the black square. In the first period of time two of her parallely exist.
Dumbledore is not a seer or time traveler, he is just a very perceptive intelligent man. There are things we know instinctively and intuitively because we know how people are going to act. Dumbledore knows Harry, and he knows that Harry will listen to any advice he gives him. He plans to tell Harry to use the time turner. So he knows that Harry will use it. He instinctively knows how Harry will use it, because he knows Harry very well perspectively. So even though he may seem to know Harry has used the time turner when he advises him to. It does not mean he is a seer or time traveler, but just someone who knows Harry too well.
Dumbledore probably did his own time traveling in other instances, but he knew too well to be careful of consequences. He was also aware what Harry had to do himself and where he had to step in.
Its like a mom instinctively knows if her kids have been good or made mischief. Not because she is a seer or time traveled to see what they did. She just knows her kids so well that she can tell.
Finally I do not think time travel is limited to the people of Harry Potter. They could have traveled back in time to anywhere. However, they could be just mere travelers or make minor changes. Major life and death events cannot be altered. Harry could not have prevented Voldemort from killing his parents, He would have simply had to fix it, or the tangent would have found a way to fix itself either by rejoining the regular loop or by collapsing.
Further Viewing/Reading/Playing Back to the Future Series
Donnie Darko
The Time Machine
Connecticut Yankee in King Arthurs Court
Dr. Who
Charmed
Xena: Warrior Pricness
Bill & Ted's Excellent Adventure
Butterfly Effect
Timeline
Deja Vu
Kate & Leopold
Quantum Leap
Twilight Zone
Final Fantasy
Legend of Zelda: Ocarina of Time
Timeshift
Ultimately this is my perception of time travel. Time travel is tricky and yes there are probably holes and paradoxes in my perception of events. This is the best hypothetical assumption that I believe explains all events in Prisoner of Azkaban, based on all the sci-fi films and shows i have seen. There definitely will be other explanations. None will be right or wrong, just varying in degrees of plausibility and credibility. Edited by return_to_hades - 17 years ago
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