I think that some of the paradoxes described in back to the future were fantasy. First of all, people cannot disappear like Marty was on the verge of at one point. The multiple worlds theory, with infinite alternate universes, dispels this paradox: if Marty went back in time he would land in and create a different time line (because he is a stranger, an alien to that time) than the one where his Mom and Dad met. He would never be in any danger, because the two realities are not linked. If he goes to an alternate past, this would not have a bearing on his future, but only on an alternate future.
In the past, in 1955, Marty changes events, which affect his future. He goes to that future, and everybody is dandy and he is pleased with the results. However, since he formed a different time line, it is necessary for him to have been there the whole time while he was growing up. In fact, there should be two Marty's, yet he ASSUMES the role of the other Marty. What happened to the other Marty, the one who he replaced? That is never resolved.
In the second movie, Marty returns back to 1955 again for more shenanigans. Now there are two of him. Okay. But once he lands in that past (again) he really is free to mess with his other Marty (who is now on another mission, there are fundamentally two of him now) while having no effect on his future. Same situation--the moment Marty lands again in 1955 he creates a new time line. The events cannot have a bearing on his future.
The letter delivery seems possible, but only if Doc lands in an alternate 1885 and then Marty traces the events to lead to an alternate 1955. But it might be hard to locate the correct 1955 which corresponds with the right parallel 1885.
Outrageous as it may seem, Marty is aware of the all the time that passed from 1885 to 1985, because his future time line is linked to it. Therefore, since it has elasped, Doc cannot travel there and send the note.
In summation, it really is impossible to travel INTO a past that has already occured. What is possible is creating a new time line, one that exists very near to the original. You can travel to a new place, as long as it hasn't happened yet. Time travel forbids travel into the past. It does allow time travel into a new time line, whether in the future or the "past", which is really a new time line that exists close to an original (two 1955's, for example). Your own essence becomes involved with the creation of a new time line, and I call this a timesplash. Like a rock that creates ripples on a still pool of water, a timesplash heralds a person's arrival and the creation of a new time line. If you travel to a paralell past, the past that you encounter may be very personal in nature, because you helped to create it.
The movies are very beautiful in that they help one think about time travel in a logical framework. There are also greatly entertaining. However, the fallacy of the movies are that there is only one past, and that the one past affects the one future. The multiple time line theory resolves any paradoxes that are brought up in the film. You can have unlimited 1955's, 1885's, or 2015's. Once you land in the past you immediately create a parallel reality. This means that your actions have no bearing on the events in the future that have also already happened. If you go back in time and kill your "grandfather", it will not wipe out your entire existence. This is because once you land and create a new time line you are killing an alternate grandfather, and that one has nothing to do with you and your later birth. The grandfather may look and act the same, but he is not the same guy you know as your blood relative. He is slightly different.
The TV show "Sliders" is closer to the truth, methinks. On that show, a genius opens a door to other alternate realities. They get lost in these multiple realities, and attempt to make it back home. Excellent theoretical proposals.
Theoretically, if you tavel away from the earth at the speed of light, time will appear to stand still, but this is only speculation as we have no way to accelerate to this speed. Some people theorise that if this was to appen you might turn around after a year, come back and the earth might have experienced a lot more time than you have (think Planet of the Apes)
I somehow think it is impossible for a human to survive at this speed.
I don't think it will be possible because time is only something humans have made up. We live in the now and the past is gone. Sure we can look back in the future if we look on something from a grate distends (because of the speed of the light) but we will never be some ware in a past
There is no actual "rule" that says time travel is impossible. In fact, Einsteins theory of relativity proves it may be possible. We know that it is impossible right now. We know this because we don't have a time machine. The problem with time travel is the vast amounts of energy it would take to overcome spacetime. Dr Michio Kaku explains it better here: http://science.howstuffworks.com/time-travel.htm
according to Einstein's theory you can but its not really traveling as it is bending space to jump to another place which in some case could be considered time travel
Please search this question on Yahoo!Answers. It has been asked bazillion of times and many folks have written reams of verbiage on it. Everything there is to be said about it has been (it's just that not everyone has said it yet). gl
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I think that some of the paradoxes described in back to the future were fantasy. First of all, people cannot disappear like Marty was on the verge of at one point. The multiple worlds theory, with infinite alternate universes, dispels this paradox: if Marty went back in time he would land in and create a different time line (because he is a stranger, an alien to that time) than the one where his Mom and Dad met. He would never be in any danger, because the two realities are not linked. If he goes to an alternate past, this would not have a bearing on his future, but only on an alternate future.
In the past, in 1955, Marty changes events, which affect his future. He goes to that future, and everybody is dandy and he is pleased with the results. However, since he formed a different time line, it is necessary for him to have been there the whole time while he was growing up. In fact, there should be two Marty's, yet he ASSUMES the role of the other Marty. What happened to the other Marty, the one who he replaced? That is never resolved.
In the second movie, Marty returns back to 1955 again for more shenanigans. Now there are two of him. Okay. But once he lands in that past (again) he really is free to mess with his other Marty (who is now on another mission, there are fundamentally two of him now) while having no effect on his future. Same situation--the moment Marty lands again in 1955 he creates a new time line. The events cannot have a bearing on his future.
The letter delivery seems possible, but only if Doc lands in an alternate 1885 and then Marty traces the events to lead to an alternate 1955. But it might be hard to locate the correct 1955 which corresponds with the right parallel 1885.
Outrageous as it may seem, Marty is aware of the all the time that passed from 1885 to 1985, because his future time line is linked to it. Therefore, since it has elasped, Doc cannot travel there and send the note.
In summation, it really is impossible to travel INTO a past that has already occured. What is possible is creating a new time line, one that exists very near to the original. You can travel to a new place, as long as it hasn't happened yet. Time travel forbids travel into the past. It does allow time travel into a new time line, whether in the future or the "past", which is really a new time line that exists close to an original (two 1955's, for example). Your own essence becomes involved with the creation of a new time line, and I call this a timesplash. Like a rock that creates ripples on a still pool of water, a timesplash heralds a person's arrival and the creation of a new time line. If you travel to a paralell past, the past that you encounter may be very personal in nature, because you helped to create it.
The movies are very beautiful in that they help one think about time travel in a logical framework. There are also greatly entertaining. However, the fallacy of the movies are that there is only one past, and that the one past affects the one future. The multiple time line theory resolves any paradoxes that are brought up in the film. You can have unlimited 1955's, 1885's, or 2015's. Once you land in the past you immediately create a parallel reality. This means that your actions have no bearing on the events in the future that have also already happened. If you go back in time and kill your "grandfather", it will not wipe out your entire existence. This is because once you land and create a new time line you are killing an alternate grandfather, and that one has nothing to do with you and your later birth. The grandfather may look and act the same, but he is not the same guy you know as your blood relative. He is slightly different.
The TV show "Sliders" is closer to the truth, methinks. On that show, a genius opens a door to other alternate realities. They get lost in these multiple realities, and attempt to make it back home. Excellent theoretical proposals.
You can watch free Sliders episodes here:
http://www.hulu.com/channels/Science-Fiction#kind=...
Theoretically, if you tavel away from the earth at the speed of light, time will appear to stand still, but this is only speculation as we have no way to accelerate to this speed. Some people theorise that if this was to appen you might turn around after a year, come back and the earth might have experienced a lot more time than you have (think Planet of the Apes)
I somehow think it is impossible for a human to survive at this speed.
I don't think it will be possible because time is only something humans have made up. We live in the now and the past is gone. Sure we can look back in the future if we look on something from a grate distends (because of the speed of the light) but we will never be some ware in a past
There is no actual "rule" that says time travel is impossible. In fact, Einsteins theory of relativity proves it may be possible. We know that it is impossible right now. We know this because we don't have a time machine. The problem with time travel is the vast amounts of energy it would take to overcome spacetime. Dr Michio Kaku explains it better here: http://science.howstuffworks.com/time-travel.htm
No, but read the Time Travellers Wife!
according to Einstein's theory you can but its not really traveling as it is bending space to jump to another place which in some case could be considered time travel
Goa-
Please search this question on Yahoo!Answers. It has been asked bazillion of times and many folks have written reams of verbiage on it. Everything there is to be said about it has been (it's just that not everyone has said it yet). gl
-Fred
Yes
maybe