Howling:What crashed the Byzantium?: Difference between revisions
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:: I am aware that I am misusing the ideas of Eugine Wigner (“the silent genius”) but it’s only TV. I’m only suggesting it because of what he did with the original Angels; this was a similar concept in some ways. Imagine Moffat trying to explain the suggestions I’ve put forward! That would be impressive telly. [[User:Jack Chilli|Jack Chilli]] 16:16, June 9, 2010 (UTC) | :: I am aware that I am misusing the ideas of Eugine Wigner (“the silent genius”) but it’s only TV. I’m only suggesting it because of what he did with the original Angels; this was a similar concept in some ways. Imagine Moffat trying to explain the suggestions I’ve put forward! That would be impressive telly. [[User:Jack Chilli|Jack Chilli]] 16:16, June 9, 2010 (UTC) | ||
:::OK, what you're missing is that you can't just uncollapse Ben's current state to give him a consistent personal history; you'd have to uncollapse every state he collapsed in the past, and that would affect everyone he'd ever interacted with in the past (probably just everything in his past light cone, period). (Also, as a side note, if the erasure is actually removing eigenstates from the vectors, then the _Doctor's_ collapsed state is no longer compatible with the superposed state that preceded it--you can collapse "A-or-B-or-C" into A, B, or C, but you can't collapse it into D.) | |||
:::And, again, your second paragraph contradicts what we've seen. You say that Ben can't vanish from in front of you. And yet, Amy vanishes from in front of the Doctor in ''City of the Daleks''. (In the "canonical version" of the story, of course, the Doctor builds a "chronon blocker", which prevents her from completely vanishing, for just long enough to undo all the changes to history. But if you screw that up, Amy does completely vanish. And, even if you get it right, she's gradually being erased from history the entire time, becoming less visible and less able to interact with everything else.) | |||
:::Nobody ever said the Web of Time is necessary for the universe to exist. (Although a few times, the Doctor has said that damaging it could cause damage to the continuum itself, you could argue that this just means the Time Lords have sort of nailed it down to the fabric of spacetime or something.) What has been said is that it's necessary for history to be consistent and causality to work. | |||
:::And if there aren't multiple universes, how do you explain the travel between parallel universes that has been seen on the show, both pre- and post-LGTW? | |||
:::If you want to say that everything the show ever said about any of this was wrong, you can--but in that case, you're really not talking about Doctor Who; you're talking about another show someone else could have written. I'll agree that there are all kinds of ways time travel can be fit into science fiction--but not all of them are consistent with what we know about Doctor Who. | |||
:::Finally, it's not so much that you're misusing strong-CI (which, by the way, Wigner was arguing _against_, not for, with his thought experiments)--I agree that the kind of misuse you're suggested is common and maybe even reasonable for pop sci-fi--as that you're trying to have strong-CI (observer-dependent collapse) and MWI (the combined state keeps developing forever because there is no collapse) at the same time, which to quote Pauli, is not even wrong. --[[User:Falcotron|Falcotron]] 18:40, June 9, 2010 (UTC) |
Revision as of 18:40, 9 June 2010
Angel Bob, of course. Well, he did. But there never was an Angel Bob anymore, yet the Byantium remained crashed. As someone here pointed out, when things are remove dform time, time rewrites itself around the remove person or event. As noted in Flesh and Stone, time is unwritten, and then rewritten. We know the Weeping Angels along with a bunch of Clerics were unwritten, but we don't know how time wrote around thair lack of existence so that the consequences remain the same or similar.
As theoriesed, with Rory having never existed, time would have rewrote around Amelia's childhood The Eleventh Hour, The Vampires of Venice, Amy's Choice (which may be gone completely, as it was only a dream involving Rory, not a real, major event), The Hungry Earth, and Cold Blood. For example, the Atraxi would have been stopped differently, and so would have all other enemies in stories featuring Rory. It is like when the Doctor tried to changed a fixed point in time in The Waters of Mars - he changed the event, but time rewrote around it so that the consequences remained the same - Adelaide's granddaughter still goes into space and all of that.
It should be noted that, even with The Stolen Earth/Journey's End out of history, all evnets that happened after it (including stories set after it in the spin-offs) will still have happened the same, or very similar, as the consequences are barely affected. The only difference would be small, such as in Planet of the Dead, all Dalek invasion references would be gone. The Waters of Mars (oh dear, a fixed point in time is retconed again!) would have been rewrote, too. Adelaide would no longer have met the Dalek or lost her parents (or so we think), but time would make it so that she stills goes to Mars and all of that business, but the events leading her there would be changed, with the same sort of consequences.
Do you understand what I'm saying? Time is unwritten (people of events, or both), but then is rewritten so that not much is changed. My big question, however, is what has time done concernignt eh crash of the Byzantium? What has crashed it in the absense of the Weeping Angels who fell into the crack? Delton Menace 22:14, June 3, 2010 (UTC)
- What we also need to consider is that the cracks erasing people are not the same as changing the future by manipulating the past. If the Doctor time travels to the past and stops Hitler from being born, the future changes, though someone may take Hitler's place in order to maintain a fixed point in time. The cracks however, erase people completely. Whether this is the same as changing the past is not known. That's something we need to take into consideration as well. The Thirteenth Doctor 22:20, June 3, 2010 (UTC)
- The simply fact is that the past is changed, whether we like it or not. Amelia never had a childhood friend called Rory, meaning, as the Doctor confirmed, her own history has been changed. That means, when she would look back at stories that had Rory in, things would have happened differently. The cracks unwrite time, and then the timeline itself seems to have an instinct to rewrite around what has been removed. Delton Menace 00:11, June 4, 2010 (UTC)
- I always assumed the peoples actions still occurred, but no one remembered them. Even though Rory was sucked into the crack, his act of preventing the Doctor from being shot still happened, otherwise the Doctor'd be dead.82.23.86.207 16:49, June 6, 2010 (UTC)Ghadius
- Remember, there's not just one simple, linear timeline. For the Doctor's, all those events with Rory still happened in his personal past, even though Rory has been erased from the past of all non-time-travelers. For, say, the Northovers, history may look contradictory and paradoxical, but they don't really know enough to be sure that's true. And for most other time travelers, there's no way they could possibly discover the paradox in the first place. And that's probably "good enough" to keep the big ball of timey-wimey from collapsing and destroying all history and causality.
- And when you look at the Byzantium, it's the same. Who knows that the Byzantium crashed? The Doctor, Amy, and River still remember the Angels, and the Clerics, so the story is perfectly consistent for them. The original Angel made the Byzantium crash, before it was removed from history. For the people coming to take River away, her story won't make any sense, because that Angel never existed. But they don't have enough information to see that there's anything paradoxical. And for the rest of the non-time-travelers of the 51st century, that's even more true.
- As for Adelaide, I don't think that was time rewriting itself around the Doctor's meddling. If time just naturally fixed itself, nobody would have to do that. Let the Daleks beat the Nazis for Churchill in 1941, or let the War Chief win WWII for the Nazis, and who cares? The reason the Doctor had to fix those things is that time _doesn't_ naturally sort itself. In this case, just take what Adelaide said at face value--she knew that what he was doing was wrong (even if she didn't understand completely _why_ it was wrong), so she was trying to undo it, of her own free will, and succeeded. --Falcotron 03:00, June 7, 2010 (UTC)
- Two Levels
- I think you should look at the cracks on two levels:
- First (for 'normal' viewers) they are simple enough for normal people to understand so they erase events but the consiquences are minor so erasing the Angels is not a big deal they are gone and local time is affected but stuff they did in the more distant past still 'stands'. Somethings else caused the crash but it isn't important. The Doctor was still summoned by River as she remembers the 'original' events.
- On the second level (for the big fans) the cracks really do completly erase events/people except from the memories of time travellers. This means that the Angels never existed at all and the erasure changes every event they have been involved in. None of these events ever happened. The universe has substantially changed. The remaining clerics came to investigate a crash but this was not caused by the Angel; the retconned universe has adapted and only allowed the least possible change for the conclusions of the versions to both be the same. All of the specialist team (that died) did no come at all; only a crash investigation team. The lives of most of them continue as they were somewhere else. Those that actually got erased may now be 'unerased' as they would not have visited the site to be erased. Alternativly they came with the normal team and in events we did not witness get erased anyway (and do did not come to the site and get erased!). That is, there are erasure conflicts and the final erasure of the Angels may overwrite the erasure of the clerics. This allows revisions of revisions (good news for Rory fans?).
- The consiquence of the second level is that there are conflicting versions of events and the events we see are only 'true' to us as we share the POV of the time travellers. We are time travelling observers just as the Doctor is so we match up with him. This does not mean that we, or him, are right. The conflict between versions may be resolved in the end and what we have seen may not be the 'final' reality. Jack Chilli 08:44, June 9, 2010 (UTC)
- But we never see history right itself this way on the show (except in terms of further erasures, like Amy in Template:VG if you don't build the chronon blocker). The Doctor or someone else has to either stop the change before it happens (Template:DW), undo the change through further time travel (Template:DW, Template:VG), or introduce a later change that undoes the most dramatic effects of the change in history (Template:DW,
). Why bother with all of this if history could just fix itself?
- Similarly, why did the Time Lords have to create and maintain the Web of Time? It's stated pretty clearly that without this, history would be fragmented and inconsistent and causality would not hold.
- I don't think history in the Whoniverse rewrites itself to stay consistent; I think it just becomes inconsistent for non-time-travelers. If nobody could ever discover the inconsistency, maybe this is OK (as far as the Doctor is concerned; the other Time Lords might disagree if they were still around), but if it's a major hole in history, it has to be fixed manually, or else. --Falcotron 09:34, June 9, 2010 (UTC)
- I am not suggesting that the timeline fixes itself. Reality is fixed by the observers observing it and creating the reality from all of the possible ones. There are an almost infinite versions of events generated by quantum mechanical processes and then an observer causes a collapse of a ‘wave function’ that sets the actual event. What we are seeing is different resolutions being caused. For the clerics the past is a different version to that of the doctors but the final result is the same: a crashed spaceship. This is a conflict because there is no final resolution; there are two (or many) explanations of the events. These are only at odds in the intermediate observations and memories of the participants. It may be perfectly fine for this to stay this way or it may be a very bad thing. The reality for one observer may not need to match the reality for another except at points where they interact with each other directly.
I have not read any of the novels so an unaware of the much of the web of time but isn’t the key to maintaining it to see that the events happen. Perhaps the Time Lords enforced consensus about events and their consequences. The things between these key events may have happened differently for different observers. Now, with no Time Lords there is no consensus and the whole of reality is mutable, the fixed points are not fixed at all and reality is literally whatever you think it is even if you think it is a fairytale. Jack Chilli 10:59, June 9, 2010 (UTC)
To clarify I am suggesting that the conflicting realities are resolved by concious beings (one of the most popular QM interpretations in fiction but not in real physics). When changes happen then the confliticting reailties intersect in such a way that they are compatable. This happens when one concious being interacts with another. If the doctors talks to a cleric at the end of the story then the reason the cleric is there will not match the Doctor's but all of the evidence present would match ethers history: there is a crashed spaceship. The cleric may say that it crashed because of an asteroid impact and the Doctor an Angel; they are both correct. The realities have to be compatable or the conversation cannot happen because the realities are not compatable so no communication can take place. The 'histories' of the two are as similar as possible (the spacehip has crashed) because this is the most compatable set of versions. Jack Chilli 11:21, June 9, 2010 (UTC)
- Well, the Web of Time was also mentioned on TV, and, although they did go into more detail in the novels, they've discussed all kinds of related things--in particular, the idea of "fixed points in time"--quite a bit on TV, even (maybe even _especially_) in the post-Gallifrey universe. And yes, the key to maintaining it is, essentially, making sure the important thing happen--because they're not going to happen on their own.
- The fixed points were never fixed in the sense that they were _impossible_ to change (although Template:VG implies that they're _difficult_), but that it was a very, very not good idea to change them. Again, watch Attack of the Cybermen and play City of the Daleks for similar pre-LGTW and post-LGTW examples. Even the Trickster can't just change things willy-nilly; he has to use his mostly-undescribed but apparently-super-powerful abilities to fix things up around his changes, and, as Template:DW proves, even he can't always pull it off.
- Meanwhile, your idea that conversations can't happen between people on incommensurate timelines is directly disproven by the conversations that Amy has with the Clerics in Template:DW ("Who's Pedro?", etc.).
- The question is, when Crispin and Phillip were erased, did the other Clerics have a brand-new history created for them, which was self-consistent but inconsistent with Amy's history? Or did they just have a self-inconsistent and paradoxical history and not notice?
- I understand your point about strong-Copenhagen QM; I just don't think it's relevant here. It doesn't explain where this other history would come from and what would make it consistent. Nor does it explain why anyone would bother trying to keep history consistent if there were already a process that does it automatically.
- The simplest answer is that there is no such process. The Clerics' new history is the old history, minus Crispin and Phillip. It's inconsistent and paradoxical, but nobody noticed. If Amy had pushed them, if she'd asked, "Why can you only remember 18 clerics when Bishops always command 20?", that would have exposed the hole in their history. (Sure, their brains would probably fill in a reason, but that would be pure confabulation, with no ontological substance, and it would likely be different for each one of them.)
- This is exactly what happens in Template:DW--Amy is sad, but her sadness is a secret even to her, and in her Rory-less timeline, there is no reasonable explanation for it, so she just doesn't believe that she's sad--and yet, she is. --Falcotron 12:55, June 9, 2010 (UTC)
- The conversation about Pedro is compatible. The cleric has arrived at that point without the need for Pedro to exits by mechanisms we have not seen (a different personal history). Any has arrived through the history we have seen. Both are there and Pedro isn’t. Amy can explain this because she knows that Pedro has gone off and been swallowed or killed or something, the cleric can explain it because he knows that there was never anybody called Pedro there first place. They are both right. The only thing that need to be consistent between then is that they are there and communicating (although it is worth thinking about the source of the radio Amy has).
- As for the Universe fixing itself it is actually the conscious entities that are resolving the reality by observing it. When reality collapses due to the erasures they resolve the reality differently (but close to the ‘original’ as this is the most likely state of collapse that is consistent with their histories) The other histories are generated to explain the current state; a kind of Final Anthropic Principle thing (the universe is only in existence because it has been observed by conscious entities and therefore consciousness is a necessity for the universe to exist at all. So the think that is remaking the universe (but differently) is everybody; the universe itself does not need to.
- So there is no consistent history only a personal history. These do not have to be consistent except in explaining the present moment as being consistent with some kind of past.
- If Amy were to challenge the clerics then they would have a perfectly good explanation of why they were there; probably far more sensible then hers. Their history is exactly as real as hers but obviously they are not compatible.
- I don’t think it’s reasonable to say “It’s inconsistent and a paradox but it’s OK because it is ignored’. This means that the Clerics have no idea why they have gone to investigate the ship or why it crashed. Paradox builds upon paradox. You might as well stop speculating because you can just go with ‘everybody forgot’ without explaining why they forgot – what thing/mechnism cleverly gave them new memories? Jack
- Amy is sad because some part of her remembers Rory. The TARDIS she was dragged into may have helped her to keep a tiny inconsistency. Something tiny was preserved and I am sure we will see how soon.
- Please sign your posts with four tildes (~). Also, please try to use consistent indentation; it makes it very hard to follow otherwise. I'll try to fix the indents and then come back and answer. --Falcotron 13:57, June 9, 2010 (UTC)
- If the conversation is "compatible", I'm not entirely sure what you mean by the word. They both have different histories, and those histories contradict each other. If you're saying conversations can only happen when the people are both there to have the conversation--well, yeah, but so what?
- As for the idea of observer-mediated collapse creating the new history, that really doesn't make sense. Something has to be in a superposition of states before it can collapse to a simple state through observation. Once you're going with CI, the other possibilities all vanished when they were observed in the first place. If you want to keep all possible histories around, you have MWI (or consistent histories or another related interpretation) and you don't get observer-mediated collapse. (And adding that the erasure collapses reality just makes it worse--if the erasure is already doing that, what's left for an observer to do?)
- Saying that personal histories "do not have to be consistent except in explaining the present moment as being consistent with some kind of past" is a null statement. That's what a consistent history _is_--a history where, at each point, all of the facts, including records of the past, are consistent with each other.
- Saying there is no consistent history other than personal histories is denying the entire point of the Web of Time and the general reality of the Whoniverse. The Time Lords created a meta-structure that guarantees a shared consistent history. Without that meta-structure, there would be no personal consistent histories.
- For Pedro's history to be consistent at the point Amy is questioning him, one of two things must be true. Either the entire history of their church organization must have been changed so that Bishops normally only lead 18 men instead of 20 (which would mean countless changes to countless other expeditions--which will of course need to be changed again once Pedro vanishes too), or some special circumstance must have intervened that for some reason forced them to go out with 18 people instead of 20. The second one sounds more trivial, but it's still going to require creating and modifying all the strands of history that lead up to that special circumstance, and which is still going to reach back and out indefinitely.
- Why isn't it reasonable to say that Pedro's history is inconsistent and a paradox? This is exactly why changing time willy-nilly is bad: it leads to inconsistencies and paradoxes. That's why the Time Lords had to create the Web of Time in the first place. That's why the Doctor is freaked out about Earth being destroyed in 1986 or humanity being killed off in 1963, etc. (I mean beyond just the liking humans bit--he's freaked out in a way that he expects the Cybermen and Daleks, respectively, to be able to understand and even to agree with.)
- The surviving Clerics went to investigate the ship because River Song convinced them they had to. Why did she do that? There is no answer, in their timeline. That won't necessarily stop them from looking for one. They might be happy with the belief that she was conning them, or that she was wrong. Or maybe they'll subject her to some perfect futuristic lie detector, and re-evaluate all of her evidence. But it doesn't matter how deep they dig; they'll never get to the answer. And, most likely, the won't dig far enough to prove that there is no answer.
- Of course they could ask River (or the Doctor or Amy), who could then explain, "You went there because of Weeping Angels that in my timeline existed up until they fell into the crack and no longer do, but in your timeline never existed." And maybe they could prove River isn't lying or crazy, and her temporal physics is perfectly sound. But even then, there still was no consistent reason in their timeline. Their present is not consistent with their past, period, even if it's consistent with someone else's past. Therefore, their history is not consistent. (The overall history of all of the timelines combined is, of course, consistent, but that doesn't buy you anything useful. And, again, if it were useful, the Web of Time would be unnecessary.)
- Whether that's "OK" is a judgment call. That's the way the universe _is_, unless someone fixes it. I suspect the way the Doctor makes those calls is that unobserved paradoxes are an acceptable part of the big ball of timey-wimey, and not worth the effort to fix; it's only observed paradoxes that need to be prevented or undone. (I also suspect that the Doctor is just "pretty good" at predicting the difference, not perfect.)
- As for "what thing/mechnism cleverly gave them new memories" in my version--the human brain. The brain does this, all the time, even with no time travel. (Last I heard, "fuzzy trace theory" was the hot new explanation for what I'm talking about among cognitive psychologists, but I'm sure that's been discredited and the phenomenon has been split in two again by now.) --Falcotron 14:45, June 9, 2010 (UTC)
- Sorry if the i have not explained clearly. I will try again.
- I am indeed suggesting that virtually all of history and reality changes when somebody disappears. Imagine I am with two brothers Frank and Ben in a pub; they are virtual strangers. I am an experienced time traveller but the brothers are not. Frank nips off to the toilet and is erased from history. I am suggesting that Ben never had a brother at all. The crack caused the disassociation (not collapsed it) and Ben’s history is now not consistent with the ‘facts’ (the current quantum state of the universe or something like that). Ben’s past changes otherwise he could not be where he is (brotherless in a pub). The previously collapsed wave function that gave him his history is no longer collapsed. Ben now has an almost infinite number of histories (none of which contain any connection to Frank) some of which end up with him being in the pub alone with me and many more that do not. Ben is a conscious entity and cannot exist in this indeterminate state so his consciousness causes the wave function to collapse once more and one history resolves itself from the near infinite. This may be the path of least possible change (remembering they every event that involved Frank is changed so that’s nearly everything so a lot has changed). In effect his consciousness creates a history that is now consistent with there never having been Frank. Not a memory of a history; an actual history including new memories.
- I have the same history as I did before Frank was erased because my time travel thing has protected me. My past is fairly solidly fixed and my present can’t suddenly change. As I am in the pub with Ben he cannot vanish so the only valid histories the wave function can collapse into are one that end up with him being in the pub in front of me. Most of the possible histories can’t form and so –pop- Ben is with me but he never had a brother. He will be able to tell me exactly how and why he is in the pub but it will not match my story. He will remember coming in with me; everybody else will remember that too. It is their reality and it is a valid one. Mine is different but valid to. All of the non time travellers have a history that is totally consistent with their pasts because they are the real pasts.
- The universe has changed and now seems wrong to me but my history needs to be consistent too. What I mean by consistent is that Ben can’t vanish from in front of me as this would alter my time traveller history (which is apparently a special case). I would not have a set of observations that would lead to me being in the pub with Ben if he were never there in the first place. Although thinking about it I could have a consistent history that does allow for this if say, Ben was transported away by a matter transporter the instant his brother is erased. If I were not present then Ben might not have been in the pub at all; who goes to the pub alone; there would be less restrictions on the changes that have taken place. My time-traveller presence enforces some restrictions.
- The doctors presence at the crash site enforces the restriction that there must have been a crash (he has observed it). The consequence is that the clerics can only form new histories (ie collapse the new wave functions resulting from the erasure) that contain the crash. This has the knock on effect on virtually everything else. The clerics remaining towards the end of the story have valid reasons to be there. They are not being self deceptive at all. It would have been nice if there was a conversation with them about what they saw happen.
- The doctors is genuinely surprised that time can be rewritten despite all of the ‘changes’ he has made to time (monster in the window is the latest one). The cracks seem like a process that the time lords did not encounter or understand. The Web of Time may not be necessary for the universe to exist at all; it may only be needed for the universe to exist how the Time Lords wanted it to; they wanted a universe with fixed chains of events and made it so. Perhaps there are no more “fixed points” (which were only arbitrary plot devices mostly) anymore and the web has gone. Every story is valid; every possibility is open. The past can be almost totally rewritten and there is no problem with continuity and no paradox. There aren’t even multiple universes; just a past that is in flux as much as the future.
- I am aware that I am misusing the ideas of Eugine Wigner (“the silent genius”) but it’s only TV. I’m only suggesting it because of what he did with the original Angels; this was a similar concept in some ways. Imagine Moffat trying to explain the suggestions I’ve put forward! That would be impressive telly. Jack Chilli 16:16, June 9, 2010 (UTC)
- OK, what you're missing is that you can't just uncollapse Ben's current state to give him a consistent personal history; you'd have to uncollapse every state he collapsed in the past, and that would affect everyone he'd ever interacted with in the past (probably just everything in his past light cone, period). (Also, as a side note, if the erasure is actually removing eigenstates from the vectors, then the _Doctor's_ collapsed state is no longer compatible with the superposed state that preceded it--you can collapse "A-or-B-or-C" into A, B, or C, but you can't collapse it into D.)
- And, again, your second paragraph contradicts what we've seen. You say that Ben can't vanish from in front of you. And yet, Amy vanishes from in front of the Doctor in City of the Daleks. (In the "canonical version" of the story, of course, the Doctor builds a "chronon blocker", which prevents her from completely vanishing, for just long enough to undo all the changes to history. But if you screw that up, Amy does completely vanish. And, even if you get it right, she's gradually being erased from history the entire time, becoming less visible and less able to interact with everything else.)
- Nobody ever said the Web of Time is necessary for the universe to exist. (Although a few times, the Doctor has said that damaging it could cause damage to the continuum itself, you could argue that this just means the Time Lords have sort of nailed it down to the fabric of spacetime or something.) What has been said is that it's necessary for history to be consistent and causality to work.
- And if there aren't multiple universes, how do you explain the travel between parallel universes that has been seen on the show, both pre- and post-LGTW?
- If you want to say that everything the show ever said about any of this was wrong, you can--but in that case, you're really not talking about Doctor Who; you're talking about another show someone else could have written. I'll agree that there are all kinds of ways time travel can be fit into science fiction--but not all of them are consistent with what we know about Doctor Who.
- Finally, it's not so much that you're misusing strong-CI (which, by the way, Wigner was arguing _against_, not for, with his thought experiments)--I agree that the kind of misuse you're suggested is common and maybe even reasonable for pop sci-fi--as that you're trying to have strong-CI (observer-dependent collapse) and MWI (the combined state keeps developing forever because there is no collapse) at the same time, which to quote Pauli, is not even wrong. --Falcotron 18:40, June 9, 2010 (UTC)
- But we never see history right itself this way on the show (except in terms of further erasures, like Amy in Template:VG if you don't build the chronon blocker). The Doctor or someone else has to either stop the change before it happens (Template:DW), undo the change through further time travel (Template:DW, Template:VG), or introduce a later change that undoes the most dramatic effects of the change in history (Template:DW,