My initial understanding of was was happening is that every time Source Code was invoked it spawned a new parallel universe, created entirely by Source Code.

So the question was, how did Source Code know all of the stuff outside of the direct experience of Sean Fentriss such that it could be used to accurately mirror what was had happened in the real world.

In other words, if all of that information is already in the computer, there should be someway to query it more directly.

But instead, I think it is correct to say that without the program people understanding it, they were actually injecting just him into the alternate reality that was, because it was forked from their specific moment of reality accurate.

So the movie explains it, but the movie doesn't explain why the scientist guy would think what he thought was the way Source Code works, since that doesn't make sense.

I suppose if there was an actual alternate reality spawned each time Capt. Colter Stevens (his porn name, I presume) was introduced via the Source Code procedure, it would not be reliant on the brain memory storage of the subject being replaced in that reality.

Sure, there's no explanation of why the programmers think they are tapping into a dead memory bank that's somehow subjectively malleable for its 8-minute duration. That seems a rather large error if indeed what's happening instead is the spawning of an actual alternate reality. But, yeah, that's the point of the film's McGuffin - they got it all wrong!

Personally, I think this film handled its lack of believable sci-fi explanation better than most, by rationally stating - in the midst of a real-world, time-of-the-essence emergency - that every second spent explaining the science is time detracted from completing the mission. To me, this is all the respect a film McGuffin deserves, and better than one usually gets.


Personally, I'd rather consider that Capt. Stevens ends up in an internally-generated fantasy world while still a lump of meat in the "real" world where he is not taken off life-support (that only having happened in his fantasy world). Admittedly, there are problems with that theory, not the least of which is how are we seeing him taken off life support if he's not "there" to witness it?

But, to me, that's less of a problem than him being able to send a text message from one particular alternate reality where the train explosion never happened and thus Source Code was never invoked ... to a completely different parallel universe where the Source Code was used, and thus Goodwin feels honor-bound to terminate his life-support. By the film's internal logic, he would only be able to text the Goodwin at the control center pre-Source Code, yet we see her receive the message in the post-Source Code control center.

Boggle on purpose, or by mistake? We'll never know.

But, to me, that's less of a problem than him being able to send a text message from one particular alternate reality where the train explosion never happened and thus Source Code was never invoked ... to a completely different parallel universe where the Source Code was used, and thus Goodwin feels honor-bound to terminate his life-support. By the film's internal logic, he would only be able to text the Goodwin at the control center pre-Source Code, yet we see her receive the message in the post-Source Code control center.

Maybe I'm misunderstanding you but his text message did not cross from one reality to another. It stayed in the new alternate reality where he saved everybody on the train.

She unplugged him in the first reality based solely on his request and their conversation, that her never saw a text message.

But if she received the text in the universe where Colter never went on a mission, and thus never proposed he could do that ... was she just totally confused and baffled by receiving the text from the lump of meat in the freezer in the corner? Perhaps as confused as I am right now?

Assuming the text was sent and received in the same universe, why was he sending the text? In that universe, he was never sent on a mission. I mean, he was (and I guess he himself has memory of that), but his action in stopping the bomber before the train explodes changes the reality in that universe such that he never goes on the mission. Colter is not there at all, only Sean Fentress.

But even if this Sean is really Colter with all of Colter's memories ... Colter would know that in his current reality, he was never sent on a mission and thus Goodwin would not understand the significance of receiving a text from him. So why do it?

No. She's aware of what her project's mission is. She gets a text message that claims to be from the lump of meet in their freezer.

She might not believe it but the message tells her things about the program that are almost certainly super secret and also tells her she's going to learn about a foiled terrorist attack on a Chicago-bound train and that the terrorists name is X.

She's walking into Jeffrey Wright's (the black guy) office to show him this when she overhears the Army guy telling Wright about the terrorist attack, confirming the text message.

The message further tells her that is was her and him working together that actually foiled the message and so she should now understand what is really happening when, in this new timeline, they actually do use him and start spawning yet more alternate realities.

This actually creates an interesting idea for one long chain of alternate universes. Each time they use Source Code they prevent the terrorist act
in question and thus spawn a timeline in which the terrorist act did not occur and so Source Code was not yet put to the test until ultimately the program is defunded and shut down for no longer being needed.