Time Paradox

[Dr. Jameson]

The topic is the theories and facts that surround the passage of time and time travel. I would like to start this discussion with anyone's thoughts on the "butterfly effect." Is it true? Is it false? I believe that the answer is true.

[iNow]

True... within reason. My flatulence won't make a planet 49 galaxies away change it's orbit in any meaningful way, for example... It may change the composition of lifeforms in the dining room, however.

[swansont]

What's the connection of the butterfly effect to time? Or time travel?

[ACG52]

What's the connection of the butterfly effect to time? Or time travel?

 

 

A movie with Ashton Kutcher.

[Dekan]

The topic is the theories and facts that surround the passage of time and time travel. I would like to start this discussion with anyone's thoughts on the "butterfly effect." Is it true? Is it false? I believe that the answer is true.

 

Deeply interesting question. The "butterfly effect" in time-travel was explored in Jack Finney's 1970 SF novel "Time and Again".

 

A worried time-traveller, who's just made a brief excursion back to the 19th century, is reassured:

 

"You made no interference with events, except - that your very presence was an event. A tiny one, but people saw you, spoke to you, momentarily at least. What trains of thought might possibly have resulted? Influencing events that followed....but there is no least evidence that your presence affected subsequent events in even the slightest way. This confirms a theory we've been calling "twig-in-the-river" - Time is often compared to a river, a stream - what happens depends on what happened upstream earlier.

It's possible that even the smallest of twigs might have an effect, might lodge and eventually cause a barrier that could affect the entire course of that great stream.

 

But what are the chances? There is virtually a 100% probability that a twig tossed into that enormous and incredibly powerful current, into the momentum of that vast Mississippi of events, will not affect it one bit."

 

Of course, that was "famous last words" - or was it? I heartily recommend the book. (Haven't SF writers thought of everything already!)

[Dr. Jameson]

While the butterfly effect is only a theory, comparing it to a river or stream is not, in my opinion, an accurate comparison. Let's say for instance that I go back in time and kill a person who we will call Mr. X. The flow of time would change and create a new time line where Mr. X no longer exists. A universe where everything Mr. X has done as a contribution to humanity has never happened, and therefore has never influenced certain people or certain levels of thinking and therefore removing certain events. Imagine that Charles Darwin had died when he was young, or never existed at all. The theory of evolution would have never been thought of or discovered. If it were discovered by another individual, it may have not made much sense and become another footnote in history, completely denounced my modern man. These are just some vary large "for instance" events. But even the appearance of an individual in the past could completely alter the present. Some dirt has been shifted to a place where it wasn't before, or even a subtle breeze flowing around this individual's body, or the new appearance of CO2 or new reduction of O2 from the individual's breathing. These slight differences could effect the world in the future dramatically.

 

Now back to the topic, A stream will flow around a stick or rock and eventually flow unchanged, or flow in the same way as it did before. If past events were altered, an entirely new stream would be created, which is why I think it's not an accurate comparison.

Edited September 10, 2012 by Dr. Jameson

[swansont]

The kind of time travel you appear to be describing isn't consistent with the laws of physics as we understand them. Here's a rundown of the restrictions known physics places on time travel.

http://discovermagazine.com/2010/mar/02-the-real-rules-for-time-travelers

[Dr. Jameson]

Ah yes, this is talking not only about time travel to the past, but to the future as well. However this is flawed almost immediately. In the theory that every event is predetermined and therefore creating a single line which time follows, thus denouncing free will, a person who travels to the future would not be able to meet his older self because that person would not exist. If Mr. X travels one day into the future to meet himself, that would mean he would not exist in the world for exactly one day because he would be traveling to the future. He would reappear to find that he was gone for a day and that would be it. However time does not flow in a single straight line, we only perceive it that way in this dimension. Every "choice" that we individuals make shapes the fabric of time and creates the dimension in which we live. Lets call this dimension in which you are reading this sentence dimension A. You may reject this theory and decide to post a new comment disproving it. You may accept this theory and decide to post nothing. You may read this and decide to leave the forum and so on... Whatever decision you decide on has just created a new dimension where you did this differently. Now there are approximately 7,000,000,000 people on earth at any given moment, so lets assume that half are awake and active at any given time so 3.5 billion. We can safely assume that each person makes at least 1,000 decisions a day (this number should be significantly higher). That would mean that 3.5 trillion decisions are made every 24 hours. The number of universes able to be created is nearly too large to count (you can use the permutations formula to figure out this number). This same theory is also the reason time travel is so tricky. If a person were to go into the past (meaning he travels back through the events of dimension A) he could then alter the past. However, on his return home one of two possible outcomes will occur:

 

1. He will be transported back to the present dimension A where everything is as it was before he left and nothing has changed (his changing of the past has now altered a different dimension where he was transported through time.)

 

2. He will move down one out of trillions of new paths leading to new dimensions that all start at the point that he altered.

 

To put outcome 2 more simply, imagine that you have a tree which represents time and people's decisions. Starting at the base of the trunk and moving up you paint a single branch orange, but you only follow one branch until it ends at a single leaf, this is dimension A. By changing the past you have created new branches that start at whatever part of the tree you changed and have now eliminated the orange branch all together. You are now forced to paint a new branch starting at whatever point was changed and follow it. This new branch you have followed is one new dimension which has been created due to your medaling of the past. If one were to travel to the future the same thing would occur. The person would appear in a time where he has not existed since the time that he transported.

Edited September 11, 2012 by Dr. Jameson