Question: Will it be possible to go to a different dimension when im still alive

Geraint Evans answered on 26 Mar 2021:

Who knows? If they exist, maybe! As the others have said so far we only have theories or hypotheses.
It might actually depend on what you mean by a dimension. Usually when we say dimension we mean (roughly speaking) the directions you can move in – so up and down, forwards and backwards, left and right are the three dimensions we are familiar with (some would even say time is a dimension, but that’s not important here!). Ideas like String Theory predict up to 10 dimensions! Some of the extra ones are curled up, into a tiny cylinder (think of a never-ending Pringle can) and is so small we can only travel along it and not around it. Because they’re so small it would take a lot of energy to detect these, so it’s unlikely.
If you’re talking about something like a parallel universe, then one way of thinking about Quantum Mechanics would be that every measurement we make, the world splits according to the different possibilities. People like to think of it like this: if you go outside one day and measure the wind is travelling south, then you would have created three other “universes/worlds” with three other versions of yourself where you felt the wind going in the other directions instead (north, west and east). It’s a bit more complicated than that, but that’s one way of thinking about it! Unlike String Theory, Quantum Mechanics has been experimentally tested, and there is a bunch of wacky experiments going on right now trying to see if there is something like parallel universes. We haven’t gotten very far I think but still, it’s exciting!
Those two are probably the most popular beliefs about different dimensions/alternate realities but there are a bunch of other cool and crazy ideas. For instance we don’t know what happens when you go into a black hole. Some people think these could take you to otherwise inaccessible places (like other dimensions). But I do agree, it does seem unlikely – we need to prove they exist first. Being positive, I think we will get a lot closer to finding out if they do exist, whatever “they” are and travel between would be a whole other challenge. But hey, why don’t you give it a try, it’s not going to happen until someone says they’re going to figure it out!
Apologies for going overboard with the long answer but I hope it has given you some idea of what the physics community thinks!