I wanted to ask you all about a certain and pretty nice plot device.

Dimension Travel.

I've seen it done here with Sweetie Chronicles: Fragments, along with occasional fic concerning the canon characters seeing one of alternate universes, but what is main opinion on that?

What do you think when characters travel through the dimensions and universes? When they see more than one version of a pony? How much dimensions is enough? What if they are simply passing through? What if the author works with the author of the other fic to make that said crossed over dimension travel chapter? What is your opinion on authors working together on crossovers?

Discuss.

904053
These things are almost always cool. I remember one non-fanfictoin example being the corssover between Doctor Whooves & Assistant and Doctor Whooves Adventures. There aren't as many fan fiction examples, but I'd love to see some more.

It's an interesting concept to say the least. I prefer to use it in comedy and combine it with subtle and less-than-subtle fourth wall humor but there are other applications.

Foundation, stories that delve in time-travel, alternate realities and dimensional crossing over require foundation for the audience to understand. Because reality is subject to our interpretation, might I suggest that you use perception to define the realities as you explore them, primarily on the main character or characters. It's a subject that can cause a lot of confusion but can be interesting if pulled off well, perhaps open the door for new possibilities.

The possibilities are limitless, you can literally go anywhere with this idea. But in order to keep a captivated audience and also to prevent from losing yourself, tether yourself to a rock as you dive into uncertainty. If the subject is travel, I recommend the origin.

What I'd like to see is a dimension travel/crossover between universes other than MLP but populated by ponified versions of the original cast of those other dimensions/universes. I was planing to do something like that once I finished my fanfic but at this rate, I may never finish it.

904053
904066

Actually i have a collab that's pretty much a massive crossover complete with a central hub location where plenty of ponies can meet their alternate selves. The central story line is incomplete but it's also set up to be a sandbox universe as well so authors that don't want to work on the main story can have a group of four to five canon characters and one OC can have adventures. Or if they want, they can simply do a "Life on the HQ" story where the different ponies are.

On topic, I find dimensional travel a fun idea to explore as it opens up, literally, worlds of possibilities.

Well, for me it can be done either comically or in a very serious way. I personally tend to stray away from crossovers of things I'm not familiar with even though the mark of a good crossover is if it can tell its story without the reader having to be pre informed. But it can be used for comedy, in a dimension-hopping, fourth-wall-breaking, almost-but-not-quite-meta kinda way. Or it can be done in an extremely serious manner like in one of my personal favorites, Sunshine and Fire.

These kinds of things are always fun. I loved the Doctor Whooves audio series cross over. Unfortunately, I've always wanted to read a doctor whooves fiction where the Doctor takes his assistant back to his universe and the pony turns human, but I've yet to find one.

also, Yasahiro, I love your avatar

Hi! I hope you're doing fantastic.

I love discussions relating to Science, and further more like that!

Multiverse is an interesting topic. It purposes the idea that for every possibility, there can be another Universe. Such as, what if a background pony was the part of the Mane 6, and one of the characters was a background pony? Or Celestia could have ruled the Night, and Luna the Day. Usually, if one could actually travel to another one, of-course they would act strange. It could be random. They could travel to an Alternate Universe where Queen Chrysalis rules Equestria, or maybe even a Universe where Trixie would be the former student of Princess Celestia, or maybe even a Universe where Scotaloo isn't part of the Cutie Mark Crusaders.

Usually, Multiverse is infinite ( Or is it? ). Since there are dozens of possibilities of every single second, minute, action, or word. Maybe it is infinite, and there are definitely hundreds of possibilities for everything. And yes, I would love to read something relating to Science Fiction. ^_^x

Welp, that is all. Take care, and be safe. Ciao!

I've seen cross overs done a multitude of ways. They can be genious or disasterous.

The bad ones were done with poorly thought out story lines, changing the personalities of people/ponies from the original version too much. Leaving out important details can ruin a fabulous idea. I've found stories that seemed natural to combine, but just didn't work due to a writer's lack of basic understanding of the original stories.

The great ones are so fluid, the rules of science and magic, from both/multiple worlds, so flawlessly combined, you wouldn't beleive that one story was a Scfi story and the other story was about a magical princess.

I've seen many Harry Potter crossovers. These can go horribly horribly wrong. If someone is a not nice person, no one will believe there is a secret nice side, and vice-versa, without a throughly believe-able explaination. The bad versions also made the main person god-like without any flaws, seriously not even prone to paper cuts or tripping on stones.
Then again I read a cross-over where Sailor Moon became part of the Borg. It was genious!
So yes as long as you approach it with respect, Cross-overs are amazing. Just read any "Dr. Who" fanfic. The easiest story to cross into any universe.

I actually use dimensional travel more as a plot device, kinda like Doctor Who. In both attempts at my Sanchez Chronicles crossover, I use the, by all means, normal convention within one continuity of dimensional travel to make the idea of the story possible. Of course, Sanchez Chronicles is entirely BASED on the idea of dimensional travel or spatial freedoms, meaning that anything can cross-over into the Sanchez universe and it would not only make perfect sense regardless of the series but would require very little to no explanation for how because of the Sanchezes own abilities. Hell, by the end of both stories, the Mane 6, or at least Rainbow Dash, were going to be made Sanchezes or at least honorary in the case of AJ and Twilight.

I have a little story that uses this fairly extensively.

A quick rundown of the rules:

1: Propagation

The universe follows a "Many Worlds" model, with a "lazy universe" modification that sets a barrier to the creation/propagation of alternate worldlines. Minor random events, such as the motion of electrons within an orbital shell, would only create an "alternate worldline" within the limited vicinity of that orbital shell. Larger events could create an actual Star Trek style alternate timeline, but the propagation of that would not extend beyond a distance (or a distance within a given time) whereby the information from each divergent worldline would have an affect.

IE - if Dr Neil DeGrasse Tyson claims that Pluto is no longer a moon, then the very atoms that make up Pluto do not necessarily receive any information about Dr Tyson's claims. However, if Dr Tyson uses his powers for evil, and constructs a high power laser to change Pluto's status into an 'orbiting debris field', then the scope of this divergent event would reach pluto - and any entitiy capable of absorbing the stray photons from it's fiery destruction.

2: No "Grandfather Paradox"

The staple of any time travel adventure - going into the past to alter some aspect about your past self, and returning to a dystopian future crammed full of unforseen consequences. Not applicable here. The act of going into the past (or arriving at your destination in an FTL capable ship) simply branches off a brand new worldline. If you were to build a supercomputer the size of a small moon to calculate the entropy mappings required to hop into an alternate worldline - you would simply create yet another alternate reality. Long story short - if future-you pays present-you a visit, bear in mind that your sudden death may be of little consequence. Especially if future-you is a high powered spaceman on high powered SPACE DRUGS who's been living the past few decades in a "groundhog day" sort of self atonement for present-you's seemingly inconsequential blunders.

Run...

3. A stone skipping across a lake will reach the other side long before the ripples catch up.

Given the nature of your "conveniently fast hyperdrive", the most technogically taxing portion has to deal with mapping out space. You need to know your starting position, and your destination. Provided that your space-entropy-measuring device is accurate enough to make Heisenburg spin +2/3 in his grave, your ship's drive will happily transport the whole ship there. Even if that measured destination happens to be a few miles in front of your ship's bow. And when you get there, your destination becomes your origin, and you repeat the whole process. Meanwhile, you're travelling fast enough to make the Milky Way spin in reverse (if you stare at it long enough).

If you had a ridiculous amount of storage space, you could record some of these hops, and travel back to one at a later date, effectively travelling backwards in time. If you look out the window, you might even see your alternate selves flying alongside, but pointed in the opposite direction. (but only while the drive is running)

If you launch the same ship to the same destination from two different worldlines, and your destination is farther away than the propegation of information from whence they left - both ships will arrive at the same time, in the same location. While the universe would naturally be inclined to split each of these ships off into their own distinct worldlines, the near perfect overlay may allow them to naturally synchronize in a fashion, after a certain span of time.

Naturally, this wouldn't work if the crew were moving around, and causing massive perturbations to the entropy of the universe at that particular point. But that's not an issue now.

(THEY'RE ALL DEAD!)

One day in early high school or late middle school (I can't remember, it kinda blurs together) I started to build a multiverse theory that could work for any situation, and universe, and other multiverses. The basic laws or rules I came up with was thus:
1) Whatever you imagine exists for as long as you imagine it. Whether it stays depends on whether the creatures within have enough "importance" to "imagine" itself into existence (often achieved by having enough "believers". A black universe with a floating rock will eventually fade into an endless loop, since nothing really happens and the rock is too unimportant. If L. Faust decided to keep her version of MLP to herself, it wouldn't have gained enough strength to stay for long.
1a) Said universe must also require a foundation to build up upon, or else it will fall like a card castle without a table to stand on, or go crazy and be a danger to everything else.

2) All universes, including spin offs, exist within their own "bubble." They usually float near similar worlds in a weird, multi-dimensional sort of way. Multiverses are also in their own bubble.
2a) Outside the bubble is a sea of raw energy (inspired by the Outside in the Ender's Game series). Beings who keep the bubbles from harming other worlds live/roam the place.
2b) This "Outside" is also within its own bubble, and loops with other Outsides like a infinite Mobius Strip.

3) These beings are immensely powerful, in order to counter equally powerful things nightmares and dark thoughts create. They are usually borne from heroes, who have achieved something truly great, and are hyberboled by later generations.

Ammendment4) There are exceptions. These exceptions are often times treated with extreme prejudice and/or scrutiny.
Examples include:
1) Those who don't exist within a bubble, often causes havoc to the copies of them within bubbles.
2) Those who shouldn't have joined the ranks of the Outsiders.
3) Glitches that couldn't be removed due to their nature.

P.S.: The events of Earth is a series of stories written by an Author from a different universe, as unknowable as Harry Potter figuring out how J.K. Rowling has to do with his life.