Snape and DADA

[cubfanbudwoman]

No: HPFGUIDX 112310

SSSusan earlier:
> > Hey, PK, thanks for answering this.  But, see?  I just DON'T get 
> > it!  If a person wasn't alive in, say, 1800, then why *should* 
> > he be able to go to 1800, do something which impacted the course 
> > of events, then return to the present?  It seems like such a cop-
> > out in telling a story!  
 
PK replied: 
> I think time travel just isn't your thing, is it? 

SSSusan [puts on DD voice and says]:
Alas.  So it would seem.  


PK:
<big snip of very nice description of time-line threads>
> If you step back and look at the overall timeline, assuming you're
> using the single-timeline theory, you see that as of 2004, whatever
> the time-traveling person did in 1974 (or 1800) *had already 
> happened in 2004*. The individual simply had not, from their own 
> personal, subjective point of view, *done* it yet. <snip>  The 
> things they do that influence events *aren't changes*,
> which is why I say they "had always done them" and that they are 
> not actually going back and doing things that change events.


SSSusan now:
Okay.  Now THAT'S where I lose it.  How could time [1800, 1974, 
whatever] already have happened **and** this individual "simply had 
not, from their own personal, subjective point of view, *done* it 
yet" *if* they did something important in 1800 or 1974??  How could 
they have done it and also not yet know that they'd done it?

[I'm sure many of you are just shaking your heads at me, 
saying, "Nope, there's no hope for THAT one."  But surely there's at 
least one other person out there who can't quite grasp this!?  Damn--
I'm Phi Beta Kappa, but I can't "get" time travel!!!]


PK: 
> Now, if you take the theory that going back in time DOES change
> things, producing alternate timelines, you would have one ribbon 
> going along normally, and then when someone went back in time to do
> something that *had not been done*, the ribbon would split in two. 
> The things they do that influence events *aren't changes*, which 
> is why I say they "had always done them" and that they are not
> actually going back and doing things that change events.  The 
> things they do that influence events *aren't changes*, which is 
> why I say they "had always done them" and that they are not
> actually going back and doing things that change events.
> One would be the timeline he came from, where the thing had not 
> happened.  The new one would be the same up to the point he did 
> it, and then it would branch off. (Then there are further concerns 
> such as whether or not you can actually get back to your 'home' 
> timeline -- which, it should be noted, you have not altered.) 
> 
> There is the third possibility, employed in "Back to the Future," 
> in which you go back in time and actually do change your own past, 
> which is what leads to such paradoxes as "I went back in time... 
> and corrected this problem... so I never had occasion to go back in
> time..." etc. 


SSSusan:
Okay, good--so there ARE alternatives which more closely fit what I 
had in mind.  Can anyone tell me which "version" of TT I'm going to 
find in The Time-Traveller's Wife, which I've just ordered??

PK: 
> JKR, perhaps realizing that her audience would not necessarily be
> familiar with the conventions of time travel or perhaps simply
> preferring this version, chose the option where if you go back in
> time, whatever you do there (or then) has already been taken into
> account in your own past. This is made clear by the fact that Harry
> and Hermione go through a particular time period twice, and the 
> second time through, several different things they noticed during 
> the first time are specifically referred to -- they just know what 
> those things mean this time, whereas before they didn't, or 
> misinterpreted them.  But the same things happened in that time 
> period. They just lived it twice.
> 
> This is why I think the people who say "But why don't they use a 
> Time Turner to go back and rescue Sirius?" and other such things 
> do not make sense. JKR does not appear to be writing a universe in 
> which you can actually change the past. 


SSSusan:
Thank you, again, PK, for attempting to open my eyes and enlighten 
me.  I'm doing a little better with this now....  So, in JKR's 
version of TT, you can only go back and see things as they happened 
from a different perspective; you're not really CHANGING the events 
and doing them over.  Did I at least get that much right??

Siriusly Befuddled Snapey Susan