Before I put together my long-ass comic book/LOST post, I thought I'd go over a few things about time travel on the show based on what we know. Several people I spoke with after last week's episode were confused about what's going to happen to all the characters going forward, given that they're now trapped (forever, we assume) in 1977 and how they relate to their future counterparts.
I'm going to do this in question form, since I really don't have all the answers myself and need to work some of these things out for my own benefit. :)
1) So how does time travel work on the show, in general?
Originally, if you recall, the first exposure we had to time travel was Desmond, back in Flashes Before Your Eyes, where his consciousness, not his physical body, traveled back to sometime on the mid 90's. I'm assuming his physical body was unconscious from the Swan Implosion while he was there. This seems to have been a singular event, however, as he didn't need a constant to bring him back, nor did he travel back and forth between two periods. His mind remained in the past until he was hit on the head with the cricket bat and sent back to his own time. Oddly enough, he may have changed history when his was hit with the bat since he actually got in the way of the bartender in that scene, who was the actual target.
Desmond then had "flashes" of the future after this, correctly predicting Charlie's death and Naomi's arrival until he leaves the Island in the chopper in The Constant. In that episode, Desmond's consciousness traveled a second time, this time bouncing back and forth between time periods. This was cured by him connecting with Penny, his constant, in present day. Since this event, it seems Desmond doesn't have flashes anymore.
Lastly there's the time travel by the Losties on the Island itself. Daniel stated he didn't know whether the Island was skipping through time or whether they were. Since Ajira Airways Flight 316, the one the O6 took to get back to the Island, was from L.A. to Guam, it seems that the Island certainly wasn't skipping through space, as that route would likely take them over the original location where they crashed. The plane itself seems to have landed in either present day Island time (2007) or sometime after that (remember the Hydra station looked abandoned), but we don't know for sure. The O6, on the other hand, flashed and were physically transported back to 1977.
Why did this happen this way? Something happened to the Island when Ben turned the wheel - Daniel likes to use the record analogy, but something doesn't quite fit with that. We know the Island disappeared totally in front of everyone, but it seemed like it was in the Island Losties that were actually moving through time. How do we rectify this?
Totally evidence-less guess: The Island became unhinged in time entirely - kinda like moving into a wormhole but not coming out. As a side-effect, all the inhabitants were thrown off into the time stream. Was this caused by Ben turning the wheel instead of Locke? And why did Locke have to turn it at all in order to fix it?
Which leads us to our second question...
2) Why did the O6 time travel when they encountered the Island again?
I have a quasi-answer to this, but it's going to fit in better after a future question (#4). Like:
3) What does the timeline look like for the Losties trapped in 1977?
Sawyer and company were part of DHARMA in 1977, but their 2004 counterparts that we know and love had no memory of that at all. How does this work. Methinks a couple illustrations are in order. Let's take Sawyer, for example. If we were to draw a straight timeline of his personal history, from birth to his present (which is now 1977), it would (crudely) look something like this:
In order, he was born, watched his family get conned and killed, becomes Sawyer, travels to Sydney and is deported on Flight 815. Then he crashes on the Island in September 2004, does a whole bunch of fun Island stuff, then travels back in time to 1974 where he becomes head of DHARMA security.
In 2004, the Sawyer we know has no memory of his time with DHARMA because he hasn't done it yet - it's still in his future even though the year when he does do it is in the chronological past. Another way to visualize this is like this:
This chart brings up a another point, in 1977 there are two versions of Sawyer: The one who's the head of DHARMA and one who's just a kid. His timeline is still linear, but because he overlaps himself from 1974 onward there are actually two Sawyers that exist in the world. In 1974, there's an on-Island Sawyer in the DI and a five-year-old Sawyer in Tennessee. The DHARMA Saywer could conceivably visit his younger self, perhaps even influence his life or try and change it.
Likewise, should our adult Sawyer remain stuck in this current timeline and live until 2004 when he'll be 63, he could also drop in on his younger, 35-year-old counterpart who will eventually board Flight 815 on September 22nd.
And this stays true for every time traveler - because they doubled back on their own lives, they could all theoretically drop in on themselves (or each other) at any point in which they're both still alive.
This brings us to...
4) So can any of the Losties change their pasts?
I think, with one exception, the answer to this is no. We're told repeatedly on Lost that time is fixed and you can't change your fate. The reason I think this is true is because by going back in time the Losties have created a time loop and, since this isn't "Back to the Future," if they break this loop that's the disaster Ms. Hawking refers to when she tells Desmond he has to push the button.
Think of it like this. In 1977, Sawyer saves Amy's life. Now we don't know what affect this has on future events, but suffice it to say that if he doesn't go back in time, she dies. If we assume that time is indeed fixed and that Amy is "fated" to live, then Sawyer MUST go back in time at some point or else you have a rift in the space-time continuum. Same thing with Juliet delivering Amy's baby, if she's not there the baby dies, time is changed, and (presumably) everything is destroyed.
This is much different from the way time was presented in "Back to the Future," which kinda represents the other "popular" view of time travel - you change the past, you change the future.
Ms. Hawking tells Desmond that the universe "course corrects" when small things happen and, for most people, I think she's correct. There is only one major timeline in LOST and in that timeline Flight 815 crashes, several people go back in time and the things they do in the past are the things they were fated to do. Thus two things cannot be changed if the time loop is to be preserved:
1) All the Losties who go back in time have to be on Flight 815.
2) The Oceanic 6 eventually have to get to 1977.
Sawyer and company have to be on Flight 815 because they have things they will do in the past, that's still in their own personal future. Likewise, the O6 have to go back because whatever they're going to do in '77 is fixed in time. The reason behind the Ajira Airways flash was the universe course correcting by having the Island prevent a rift in space-time by sending the O6 back to where they should have been in the first place, if Locke had turned the wheel.
Now while I don't think the Losties can change their past, I do think they can push it in the right (i.e. fixed position). If everyone was on Flight 815 for a reason, it stands to reason the someone put them there, someone with knowledge of what was going to happen - themselves. For example, I would not be surprised to see a 63-year-old Sawyer in 2004 hand Hibbs a folder with Frank Duckett's name on it, in an effort to get his 32-year-old self down to Sydney. Likewise what if an elderly Jack and Kate were the couple who were going to adopt Aaron in L.A. and bought Claire the ticket for the fateful flight?
In both these cases, you see the time loop turn back on itself, which is kinda why I like the idea. They wouldn't have gone into the past without their older selves helping them, but their older selves wouldn't be there to help them if they didn't go into the past. I could be totally wrong about this, but if that's what the writers have in mind it would be very cool to see.
Two more points:
5) But what about Desmond?
Desmond, I think, is the one exception to what I stated above. Ms. Hawking went out of her way to convince Desmond he couldn't change history. However, in the antique store, he was going to do it! And if she wasn't there, he would have bought the ring and never gone to the Island. Desmond is tied up in all of this because he's responsible for Flight 815 crashing. No Desmond and the time loop breaks. That's why Ms. Hawking had to be there - she had to convince him that it was inevitable he end up on the Island and push the button so that he'd keep to his fixed course. But he could have chose to do differently and - this was the one true thing he told him - if he did, everyone would die.
You see this with Charlie as well. Desmond told Charlie he was fated to die and saved his life three times before it came to pass. But the bottom line here is that he did change history three times to get Charlie to the Looking Glass. Again, this may be tied up in the fixed fate of all the Islanders - if Charlie doesn't unjam the radio, the Island likely never sends everyone into time, so perhaps it was Desmond's fate to make sure Charlie stays alive until he completes his task.
If Desmond can change history, I think, should Ben have killed Penny, he's going to try to go back in time to bring her back. How is he going to do that? By killing Ben in the past.
5) So what are the roles of Ms. Hawking and Ben in all this?
To me, Ms. Hawking (and perhaps her friend in the monastery) are time cops of sorts, made to ensure this messy portion of the time stream follows its proper path. She's neutral in the fact that she only cares about getting everyone to their proper place, not what happens to them.
Ben's role is much different. I think he's essentially trying to figure out how to change time for his own benefit. Perhaps he does have the Island's interests in mind, but only so that it sticks around for his own personal use. Locke's a threat because he only has access to the Island's energies (the Magic Box) by being leader of the Others. Take that from him and all his plans and hopes are destroyed.
Well, I think that's enough for now. Does that all make some sort of sense? My eventual comic book post is going to look at a time loop story that inspired the above ramblings. :)