Extra dimensions

[Imagine]

I recently read a book called "The Elegant universe".

The book was about string theory, and it talked about how in order for string theory to be possible, there would have to be 10 or 11 dimensions. I didn't believe it at first, but then I kept reading, and it used the following analogy.

Summarized, it said:

Imagine you are looking at a garden hose stretched across two cliffs from far away, and there's an ant on it. You can see the ant, but the garden hose is so thin you only use the horizontal coordinate to describe its position. This would be a one dimensional world.

However, once you get closer, there is also an extra "curled up dimension". You'd also have to describe it in the vertical direction.

Now, imagine if you had the same sort of thing in our 3 dimensional world. We could have curled up dimensions, like say a circle at every point. We'd be too big to actually notice them, since by a slight movement we'd go around them too many times, but say subatomic particles could still use them.


Now, if we had circles then that would add one dimension, spheres would add two dimensions. but we'd still be four short. One such shape that would fit all the requirements would be the Calabai-Yau shape:

The Calabai-Yau would exist at every point, like the circle or sphere would.




Now, after reading the book, I could begin to imagine 4 or even 5 extra dimensions, but I wasn't sure about the accuracy of them. Here is the debatable question:

Do we live in a universe of only 3 spatial dimensions, or do the fourth, fifth, sixth, etc. actually exist?

Discuss.

 

[Herman Li]

It's a possibility as we cannot seem to decide if Einstein's theory of relativity is more accurate or molecules are on the subatomic level are more accurate to describe how things work.

 

[Noam]

Personally, while I do see the sense in string theory, It doesn't seem logical to me. On a side note, looking at people trying to imagine extra dimensions is quite hilarious. Don't bother trying, though, since it's impossible unless you've actually seen extra dimensions in full size before.

 

[Imagine]

Personally, while I do see the sense in string theory, It doesn't seem logical to me. On a side note, looking at people trying to imagine extra dimensions is quite hilarious. Don't bother trying, though, since it's impossible unless you've actually seen extra dimensions in full size before.

I can imagine the 4th dimension... its actually not very hard... we just don't know how to travel in it yet. Say there are circles at each point. you could be traveling across these circles, sort of like alternate universes.

 

[Egu]

It's very well possible.

But in my opinion, it's all in the art of perception and how different people / living creatures perceive things to look like.

 

[Noam]

I can imagine the 4th dimension... its actually not very hard... we just don't know how to travel in it yet. Say there are circles at each point. you could be traveling across these circles, sort of like alternate universes.

No, you can only imagine a 3d projection of a 4-sphere. An actual 4-sphere cannot be imagined, since even the wildest dreams are, in some way, based on the real world. Since you cannot perceive a 4d object in irl, you cannot imagine them either.

Traveling in 4 physical dimensions seems rather deadly to me. If you put human in one of those, I think they would come out looking like a glob of red toothpaste XD

 

[Imagine]

No, you can only imagine a 3d projection of a 4-sphere. An actual 4-sphere cannot be imagined, since even the wildest dreams are, in some way, based on the real world. Since you cannot perceive a 4d object in irl, you cannot imagine them either.

Traveling in 4 physical dimensions seems rather deadly to me. If you put human in one of those, I think they would come out looking like a glob of red toothpaste XD

no - I don't imagine 4 dimensional objects. I imagine curled up spaces, such that I could disappear into another curled up dimension say, walk past an object such as a wall, and reappear.

 

[Skyraz]

4th dimension does exist. Its time.

The elegant universe is quite a interesting read, and i would recommend it to anyone interested in the Elegant side of mathematics and physics. Since the maths behind string-theory is just beautiful.

Multiple dimensions, yeah i think they exists, but dont mis understand the book. String-Theory believes there are more dimensions, but none of those dimensions would ever be visible to us. These dimension are for sub-sub atomic particles.
So people could talk about what the 5th, 6th dimension looks like, but you need to remember that its based on things that we will more then likely never be able to see, ever.

 

[Quadro]

Maybe we all see a different dimensions, it would be impossible to tell if someone sees something different, for example, if you saw circles as squares ever since you were born, then you would call what is a square in your eyes a circle, while another person who has been taught normally that a circle is a circle would see the circle(what is a square in the others eyes) and call it a circle, we ask the two to describe the shape, the one who has been taught corners are round would say round, the one who was taught to say round is round would say round. Same with different dimensions, any one of you could be seeing what I perceive as 2D while you think that your 2D is called 3D. It is also possible that I see 4D but I think I'm seeing 3D because that is what I've been told since I was born

 

[Try and run]

That's a book by Brian Greene, correct? You might be interested in The Elegant Universe by Heinz Pagels.

There's several theories centered around the idea that there are extra dimensions and universes. I'll edit this post later with some interesting theories.

EDIT: Also it is widely believed that time is the fourth dimension. I'm sure that Swan would be nice to have in this topic, seeing as physics is one of his hobbies.
EDIT2: You also might like The Animate and the Inanimate by William James Sidis. You can't check it out, as there are limited copies left, but you can find a copy online if you google it.

 

[Noam]

Maybe we all see a different dimensions, it would be impossible to tell if someone sees something different, for example, if you saw circles as squares ever since you were born, then you would call what is a square in your eyes a circle, while another person who has been taught normally that a circle is a circle would see the circle(what is a square in the others eyes) and call it a circle, we ask the two to describe the shape, the one who has been taught corners are round would say round, the one who was taught to say round is round would say round. Same with different dimensions, any one of you could be seeing what I perceive as 2D while you think that your 2D is called 3D. It is also possible that I see 4D but I think I'm seeing 3D because that is what I've been told since I was born

NO. That doesn't actually work in the real world. If one person saw a rectangle, and the other a circle, and you told both of them to sit around the table as close as you can, you would notice that one of them would either be shocked that they are going into the table, or mysteriously stop a certain distance away from it. How would that work?