Plot holes

Welcome to the lovely world of temporal paradoxes! Depending on how your world is framed, the time machine does not necessarily disappear. His death could have been a defining moment when a split in time occurred, where in one future he lived and made the machine and in another he died. This was a frequent method of dealing with things in Star Trek (The TNG episode "All Good Things" in particularly really messes with that one). See also Terminator where a kid ends up being older than his father because Kyle Reece conceived John Connor before he himself was technically born.

So no, I wouldn't throw the book across the room, so long as its made plausible and a valid explanation given.

Well, one way out of this time paradox is if when she goes back in time, she actually goes to that point in time but in different alternate reality. An alternate reality where she kills the guy. Hmmm, but then she essentially kills a different guy. I don't know, play around with that idea, you could get something workable.

the 'many universes' or alternate realities approach is the oft-used cop out for paradox problems. No harm in doing that. The fact of the matter is, there isn't a time travel story you can't completely rip to pieces if you put your thinking cap on. Case in point, the Terminator movies. Why the heck didn't Skynet simply try again and send another robot back to Sarah Connor's childhood years? Hmm...actually, that might have made a better movie than that awful, sterile CGI showreel-mess that was 'Salvation'. ughhh.

Wouldn't it be a real possibility that someone else performs that necessary part of the building the time machine? That could introduce an interesting twist.

For example: Builder # 1 builds your original time machine in such a manner: appearance, control placement, options of the time machine. You go back in time and Builder #1 dies. Instantly (going back to your concern: wouldn't the time machine instantly vanish), the time machine changes.

A Builder #2 had come along and built a time machine that you use now. (Plausible, since people invent/work on devices that do similar things all the time.) The twist could be you're familiar with machine #1, and machine #2 does things a bit differently, the buttons are in a different order, and you put yourself in a time/place you didn't mean to go. Could be fun!

Good luck!

The above sounds good, but my objection would be this:

The traveller's machine would still vanish because it's not the exact same machine as the one the dead builder would have designed.

Or:

The Honda you bring back to a pre-automobile era with you won't turn into a Toyota if you change the past so that Hondas never exist.

FWIW Please don't take a cop out approach to time travel. Do something really cool with it and think it through.

To many people approach time travel as a neat story telling trope and don't realize how complex it really is.

Primer is a good example of a thoughtful time travel movie.

How about:

Well, the traveler got the time machine out of the future before that future ceased to exist, so the time machine from the changed future still exists in the past because it's from an alternate future.

I'm trying to remember a chapter from The Fabric Of Reality by David Deutsch. It deals with time travel, and shows how paradoxes don't actually crop up due to physical laws. It deals with quantum physics in some way, but I can't remember exactly how it works.

But you could do a lot worse than to read that book in its entirety. You'd have to get it ordered in in most cases, but it's well worth the wait.

How far into your book does the paradox occur? Because if you're rewriting and it'll be a long time before the paradox issues arise, then you have time to get The Fabric Of Reality. I've got it on my shelf, but the chapter in question is a long one, and I don't feel like typing it out. But it shouldn't be too hard to find it once you have the book. IIRC it's about 2/3rds through.

It deals with people paradoxes. The one I can't remember deals with meeting yourself (which could be handy for you even though you didn't bring it up) and there's another section on stuff like killing your grandmother.

Actually, I kind of remember it now - it does seem like a cop out, though this is coming from a noted physicist and not just someone wanting an easy way out of a time travel story. It says something to the effect that if you kill your grandmother in the past, it's a different universe to the one you were born in, and due to quantum probabilities, then you would still be born in your OWN universe in order to come back in time, but in this Universe in which you killed your grandmother, you've basically acted to ensure that a you doesn't exist in this future. So, no paradox.

The Fabric Of Reality is all about the quantum multiverse. It's quite interesting, and honestly is the most supported theory in physics that deals with the idea of time travel and quantum properties.

Also, it says that a time machine is a location and not a device - so you can't "travel" a distance in the time machine, only travel in time. Wormholes are the exception. They link 2 places in the universe and allow you to travel faster than light, which is in effect time travel. Like, travelling faster than light is supposed to take you back in time.

So maybe if you're having a time machine that can travel distances, it needs to have wormhole technology inside it, aswell as a way of travelling into the future (which is far more acceptable in physics).

But I'd still recommend getting the book. If you want to write about physics principles, then you'll probably enjoy The Fabric Of Reality.

(And if you want a nice easy explanation of the multiverse, then that happens in chapter one or two, where light travels through slits. You can't have quantum phenomena without the multiverse, even though when I took that subject at Uni they didn't mention the multiverse at all, and a lot of scientists seem willing to accept the quantum nature of the universe for all the good it could do, but don't want to accept the multiverse because it upsets them. Hello, you can't have one without the other! /bitch)

This is way over my head, quantum physics and all.

It seems to me the simplest solution is to kill the guy AFTER he builds the time machine, unless there's some reason you can't do that.

What if he helped design the time machine in the hope that his involvement would help save him from the aforementioned death? Only, it ends up ensuring it.

Whatever you come up with, it's going to have to be simple enough for the reader to understand it. And it can't appear to be a contrived solution. It has to make sense logically. Good luck. It sounds like a hurdle.

Cliff face, the book you recommended sounds very, very interesting. I'll be getting it for sure. My story majorly revolves around multiverses.
Does it discuss M-theory?

As for you, Rushie, why does the inventor has to die? I mean, maybe your MC kills him and he happens to be the inventor. Or he thinks the inventor was responsible for creating the machine and he wants to kill him to undo the creation of the machine. In the former case, maybe the inventor isn't really the inventor but is someone who took credit for it. Another guy could have invented it. This way, you solve your problem because the real inventor isn't dead.

But if it's the latter case, and the real inventor has to die, then you could choose any other solution.

Time travel has been worked out extensively in SF novels. Expect your readers to be familiar with the Paratime novels of H. Beam Piper and Up The Line by Robert Silverberg.

This is the number one reason I have no intention of doing anything with time travel.

I think once I had a story with time travel. I just said screw it. You travel in time, you break causality until you come back.

That should probably only be a last resort, though. It's sort of the brute force "problems, what problems?" answer.

On the other hand, someone could probably get some good mileage off of it anyway.

I have never written about time travel. Unfortunately, my last novel contained a device that's going to allow my MC to experience a little time travel in the next installment. I have no clue what the rules to that game are. I presume it just follows logical progression as far as plotting is concerned.

I like the idea that there can be no paradoxes. I know, it's meant to be because of the mutliverse (and the example to do with meeting yourself that I mentioned has some pretty weird time-geography which is why I can't remember it well enough to say here) but I'm very tempted to do something a little fun.

It's for my comedy saga, but in a couple of the books there is time travel, but one in particular is centred around time travel, and that's the one where I want to have my MC say, "Look, some physicists have already shown that there can be no paradoxes in time travel," and then kill herself, only to then walk around from behind a tree and say, "See? Nothing to worry about."

Of course, it doesn't matter one whit about the multiverse - if YOU die in the past or the future (and not a different-universe you) then YOU are dead, end of story. But probably it doesn't matter in the context of my comedies.

I think M-theory is mentioned in the book very briefly, but it wasn't too much elaborated on. It just mentions the basics of string theory and branes, and ties it all up nicely, but the focus of the book is on quantum physics, so it all gets brought back to that.

And yes, you should all buy The Fabric Of Reality by David Deutsch. I first read it in high school for a physics project (I was rather gung-ho about theoretical physics while the next most interesting research project in my class was about photocopiers...) and then bought it this year when I was reminded of it by reading The Salmon Of Doubt by Douglas Adams - it's the one with the bulk of the book being his collected papers on just about everything he was passionate about, and The Fabric Of Reality was mentioned in one article.

Planning on re-reading it next year too. I love that book. It's my favourite physics book, of which I have about 5 that aren't text books. Meanwhile, if you're interested in science in general, I'd recommend The Selfish Gene by Richard Dawkins. This book was also mentioned in The Salmon Of Doubt. Is there nothing Douglas Adams didn't get right?

/ramble

Well, I'm definitly going to buy the book. I always took a liking to physics, just got constantly depressed my basic knowledge was shaky.

Time travel is of interest to me - quantum physics in general - I might write a book about it.

The time machine builder could have made notes someone else followed after his death. But that creates another hole in logic; Wh? Easy to understand notes or not?. You decide that but it gives good logic to the time traveler going back in time and experiencing this guy's death.

aka HG Wells "The Time Machine" is perfect inspiration here.

Ehab.Ahmed said:

Well, one way out of this time paradox is if when she goes back in time, she actually goes to that point in time but in different alternate reality. An alternate reality where she kills the guy. Hmmm, but then she essentially kills a different guy. I don't know, play around with that idea, you could get something workable.

Click to expand...

String theory ftw.