Is it possible to do time-travel without plot holes? I've avoided time travel in my setting for this very reason, I don't like plot holes, I try my best to workout the story, and answer all the proper questions. I also don't like going back in time and changing history that has already been set within that universe. Your readers(or viewers) have spent a certain amount of time reading/viewing and understanding the stories of your characters, only to go back in time, and change it.
I can imagine only one way to use time travel without plot holes : there is only one past and it can't be changed. If you go back and try to change it, you become part of the events that formed the past as it is. Welcome to the forum
That can cause problems too. Often time travel stories which use this method seem as holey as any other. If something you did while time travelling enabled you to be born in the first place to time travel then how did the whole situation come about in the first place? Surely to start off with you wouldn't have traveled back in time, so you wouldn't have created the events to allow yourself to travel back in time so the whole story shouldn't exist. Time fixing itself so the same events still happen, tends to feels like a bit of a fudge to me. Such stories can still be highly entertaining, but they don't feel hole free. The least holey method to me is if you go back in time and change things then you actually create a parallel universe that has your changed future, meanwhile the previous universe you traveled back from in the first place carries on as before.
Time travelling has a tendency to be very paradox-prone, and I'm not sure if there's really any way to get around that (unless the traveller can neither interact with nor be seen by the past world to which they travelled). On the bright side, though, this also means that people expect (and probably accept) time travelling to feel a little wonky.
Another theory I can think of was that once the universe's timeline was in a crazy state of flux. Time kept being rewritten every time someone traveled back and causing the point in history at which time travel was invented to change, until eventually a stable iteration of the universe occurs where time travel is never invented and the only time traveler left in the timeline is the one person who time traveled from the penultimate iteration of the timeline. As Komposten says, most people who want to read or watch time travel fiction aren't expecting to find something without plot holes, so if you have a fun plot based on a certain theory then go for it. Still it's fun to think about the pros and cons of the different methods of writing time travel.
I think there are fewer issues with travelling FORWARD in time, right? So you could do time-travel that way, maybe. Or you could travel back in time as an observer-only, or a sort of ghost. I think that would catch most of the traditional holes?
I suppose it depends whether you go backwards or forwards, and whether your time traveler ends up in an average place with average people and their aim is to get back, or whether they've been thrown into (for example) the theater where Abraham Lincoln is about to get assassinated and feel they need to step in. It would also depend whether the time traveler has gone to an era hundreds of years away or if they've gone back through their own lifetime. I think as long as you set your own limits and 'rules', and stick to them, you should be alright. As Komposten said, people would probably be more forgiving of the wonkiness.
The way I thought about it was the time travels could make a virtual snap shot of the time period and interact with the world in a virtual state, so no matter what they do, it isn't permanent.
I hate time travel as a device in fiction. It generates paradoxes and plot holes that are virtually unresolvable. You could simply ignore these, but that would raise a pile of questions in your readers' minds that you don't answer. Or you can settle for the many-parallel-universes idea, but you already said you don't like that. I think the only context in which time travel can work "sensibly" is in comedy. Back To The Future, Austin Powers, things like that. The Terminator made it work, sort of, but only by making it highly restricted: it's a one-way trip and you go through naked. No bouncing around the timeline on a whim. I've never written a time travel story and I bet I never will. Too much baggage, and the baggage is full of crap.
Somewhat, like the time traveler can choose the time/location they wanted to go in, and the machine creates the virtual world based on that input.
That's an interesting take on it, but I wouldn't associate it with time travel. I'm not sure what you'd call that- an observation journey?
I wrote a time travel short story a while back, that I think has no plot holes (correct me if I'm wrong). https://www.writingforums.org/threads/tick-t-tock.127321/
In general I like the concept of being an observer of the past; maybe the future as well? However to actually travel forward in time is simply to be "alive". If you meant skip forward a year say, how would you get back to the present without traveling back in time? Have your existence frozen in time until it caught up? If you intend to skip forward in time and never go back that might be possible without plot holes too numerous to count, not sure what good it would do a person, which could be an interesting exercise in thought.
I have always wondered why no one has come up with time travel where you lack the other dimensions of height, width and depth when you arrive in the past. It would make you unable to interact with the events of the past and avoid any paradox.
You speak about the bootstrap paradox and you are fully right. The same thing happen when you for example go back one hour in time, leave an item there and one hour later (when traveling back) you take it with you. The item exists only for one hour as it never existed before your time machine arrived and it will not exists after you start the travel. It wasn't created, just popped out of nowhere and disappears the same way. Particle/virtual particle pairs do something similar on the quantum level (at least this is the mathematical description). A possible solution to this is a kind of time loop : you go back in time and with this terminate your original timeline at the point where your travel starts and create a different one branching away at the point where you arrive in the past. Baaang, the bootstrap paradox and also the "where did you come if you prevent your own birth" problem (aka grandfather paradox) is solved This is more like fantasy than sci-fi. It would require that "time" or "theuniverse" has the intelligence to understand not just particle-level things but also very high level events like the death of a person or a marriage, not speaking about it's universal ability/power to act against your moves. Sounds like fighting against God. And when traveling "back to the future" you arrive to a world very different from what you've left, most probably meeting with yourself, who did not travel anywhere. A version of this is when parallel universes are constantly created (the rate of creation is widely differs in films and novels, from "a parallel universe is created every time a black hole is formed" to "one new universe every time the quantum wave-function collapses somewhere"). One thing worth to mention : the OP asked about ways to write a time-travel story without plot holes / changing the past, not about time travel without paradoxes. While all fictional time travel methods suffer from the paradoxes associated with time travel in general, a story can be written without even mentioning them. Depending on what situation you want your hero be thrown, different methods can be used. I am supposed to say here that you need to stick with that method but as we have seen a decent commercial success can be achieved by mixing them and leaving a huge amount of plot holes in the final work (yes, I'm pointing to the Back to the future series) Plot holes can be avoided with careful writing and this is true for every kind of novels, including ones employing time travel. P.S. : discussing plot holes with a plothog : priceless
Since there's no way to know what happens if you go back in time, I thought Stephen King's take in 11/22/63 was interesting. His character could go back in time (always to the same time in the same place), but if he wanted to make changes in the past (in this case, to stop the Kennedy assassination), the changes would be negated if he returned to his own time, and the changes that resulted in his original time were unpredictable.
The only way to (possibly) avoid paradox, is by assuming that time doesn't have to be completely linear to begin with, but could have one or two loops already built in. Thus, whatever happens in the past is actively what makes the present what it is. Not despite of, but because of.
If the time traveller is going back to a time and place where they existed, but their past self wasn't aware of their future time-travelling self, they could leave helpful items and clues for their past self, explaining any conveniences in the past.
I can imagine that there is a debate that could be had about whether the various sorts of time travel paradoxes are plot holes. Some readers/viewers definitely view them as such, albeit they may consider them among the more acceptable class of plot holes because they allow for the creation of such interesting plots. Then again one could argue that paradoxes exist in the real universe. You could class the fact that universe exists at all as a paradox. Maybe someone went back in time and caused the big bang, bootstrapping the whole universe into existence. It's nonsensical, but so is any other explanation if you think about it too hard.
Paradoxes are plot holes only if you write something that results in the paradox. Let's say someone travels back in time and changes major historical events that are well known and has their effect on today, then he travels back to his own age and finds himself in a totally changed world. This is clearly a plot hole (how did he travel back, how did he know what should be changed, etc...), at least for those who pay attention. If he changes only small events that are not known at the moment when he started the travel, the reader does not see a plot hole and is more indulgent about the paradox. Good point!!! Big Bang, black holes or time dilation caused by gravitational fields or fast speeds are real-world paradoxes that we must live with, however as we do not encounter them often, these do not have any effect on our everyday life. This is similar to what I was mentioning above : if you do not encounter the problem that a paradox causes you pay much less attention. Some people do encounter these. For example because of relativistic effects atomic clocks on GPS satellites run faster than clocks on Earth and without taking that into account the difference would cause a 10km ( ~6.25 miles ) error after one day : http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html
The only time travel story I've ever seen or read that I didn't have an issue with (generally I hate time travel in stories) was The Time Traveler's Wife. It was kind of like what @Vandor76 said. It was almost like all moments in time existed all at once. If he traveled back to a certain day, whatever he did while there had already happened exactly that way leading to how things were in the present. For example, one day he went back in time, and the girl he was with drew a picture. She put a date on the picture. But since they had that drawing in their apartment in the present, he told past her it didn't have a date on it. They decided to leave the date and see what happened. When he got back to the present, the picture had no date. When he asked her about it, she said she had gotten worried in the past and erased the date. But that whole conversation, him telling her about the date, her erasing it, etc. had all already happened exactly that way which is why it had no date in the present. There was no way he could've changed the outcome of that because whatever he said or did, it had already been said/done. It sounds really confusing trying to explain it like this. Some other things to note are that where and when he traveled was involuntary, and he couldn't travel with anything--no clothes, no objects, not even fillings in his teeth. So that covered some of the other issues sometimes involved.
