"Sorry to keep bursting bubbles but…..
OK parallel dimensions and branching time travel theories. The first purposes that for any moment in time there are infinite possibilities playing out in alternative dimensions paralleling our own, this is what was shown in Sliders, Stargate, StarTrek, and numerous other TV shows and film, while not about time travel per se it does bare some similarities to the branching time line time travel stories where if you went back in time this creates a change which causes the traveller to branch off into a parallel dimension similar to one you came from but taking into account the changes your being there caused. This in no way affects the original timeline you come from and that is why it can’t be the time travel used in this show. Everyone seems to be looking at the end result of time travel and not the reason for it “being” in the first place! (Insert exasperation) Why would skynet or future John even bother to send anyone back if they simply branch off into a parallel dimension when they arrive? It just doest make any sense for them to go to all that trouble when it ultimately wouldn’t benefit them!"

"I still think JC is actually Clark Kent, the son of Jor El. That's really why Skynet got so desperate it had to send someone back in time to stop him. He did not know his secret identity then and now Skynet's even more confused, with CK calling himself John Connor, Superman and the T1000 going by the name Brainiac. I would go nuts too. "

"Clark Kent did not just spring up with his super-powers out of nowhere. He had to develop them. Maybe JC has not developed his heat vision yet and gone to the fortress of solitude and found out who his real father is?
When he does, then Skynet will get it's ass kicked!
After that, he will change his name and go to work for the Daily planet as Clark Kent and meet Lois Lane?"

"The many-worlds interpretation of Quantum Mechanics predicts the existance of an infinite number of universes and that everything that could possibly happen in our universe (but doesn't) does happen in another.

The creation of John Connor created a new universe, the Kyle Reese that fathered John entered a different universe to do this therefore John's existance is independantly from the events that led to his creation. Kyle Reese in this new universe is therefore not really his father and the events of this unverse are not dependant on him going back in time. Therefore if syknet is distroyed in this universe it will still exist in the other allowing for the time traveland John's creation.
"

"Now Have you seen "Frequency"? That movie parrellel branches were not made but merged. In other words John Sullivan in Freqency remembered both pasts almost as if they were a dream but they really happened he remembered both. But we don't see any affect by the changes yet in Terminator:SCC may be because the changes they have made aren't enough yet. Like for instance more ripples in the pond need to be made. What do you think of Deja Vu in that movie the character died in the end because he prevented himself from ever traveling through time. So he had to die. But the past version of himself did recognize that somthing was different almost like deja vu. This would mean that in the end of the Terminator Series John Connor would prevent skynet and thus he would die at the end. Because he wouldn't have ever been born. I think that could also be a good ending to the series. But hey that is just a idea. But what do you think of the idea I talked about with regard to my Frequency and Deja Vu theory. These are types of Time travel that could be used instead of the parrallel branch theory."

"Let me put this into a “personal” context to help everyone understand why I don’t support branching time line time travel.
Let’s say for the purpose of argument you work in a nuclear power station and one day while walking down a corridor a pipe bursts spraying radioactive steam through the room, thinking quickly you exit the room and go through decontamination. Unfortunately the doctors tell you the dose was fatal and you only have 2 weeks to live and YOU are going to die a horrible painful death.
But as luck would have it your husband/wife (insert whatever works for you) has invented a time machine and tells you they can go back in time and prevent the accident from happening all you have to do is tell them to do it.
So here’s the question, what type of time travel is going to benefit YOU?
The single timeline where the accident can be prevented and the future is changed OR
The branching timeline where your partner lives happily ever after in an alternative timeline with another version of yourself while YOU still die a horrible death except you now die alone

Now I’m no expert in time travel and I don’t pretend to be. To be perfectly honest I don’t even think its even possible, but for the sake of argument and to explain the event on this show I have described a type of time travel that works within the context of “this show” however if I’m wrong then I’m wrong and I will be the first to admit it BUT what really gets up my nose is people saying “I saw this film with this particular type of time travel so that’s what they are using in this TV show” ???? Every film that uses time travel uses whatever type of time travel that works for the plot of THAT particular film, will everyone stop trying to pigeon hole this show that way when half the time it doesn’t even make sense!."

"Sounds cool. I like the idea. How do you know quntum mechanics? Or did you get this idea from a movie?"

"That's my point bit's and pieces need to be applied. Nothing will work perfectly. That's why Cameron is keeping secrets. So as that her mission objectives won't cause other characters to do dumb choices. She may know how to deal with the time travel thing even more than John Connor's younger version may be able to understand. I just don't know for sure anymore because thier are so many theories that somtimes I just want to say why do we wait and see. But if you saw Deja Vu yo will relize that maybe that idea will work better. Just go see the movie then respond to me again and let me know what you think. You may have to watch it a few time to understand. Because that time travel movie may be the most confusing the first time through"