Can someone explain to me dimensions

[CODE-D]

The difference or rather meaning between another dimension(universe) as opposed to 2d, 3d etc.
Is there something or are people just using the word dimension when they should be using universe? because whenever they do this(for say a crossover) its usually a 3d universe meeting another 3d universe.....

 

[Thaluikhain]

It's using the word in a different way to usual, yeah.

Now, you could argue that if you had those different "universes", the way they'd be arranged could be described as dimensions.

Like if you had universe X which was similar to universe Y which was similar to universe Z, which different to X, and you had to go through Y to get from X to Z or the other way around, you could plot the on a line going X Y Z, and say moving from one to the other is travelling along that dimension.

It's not from another dimension, any more than birds flying above us while we walk on a 2D surface is, but sorta kinda.

 

[Vegosiux]

Yeah, there's often that "other dimension" business that would be more accurate as in "other universe".

Now, "dimension" is basically a number that tells the minimum number coordinates you need to specify any point in a given space; and at the same time, the maximum number of existing unit vectors (ergo, vectors with length 1) that cannot be expressed as a combination of other unit vectors in a given space. So, in 3-dimensional space, you need 3 coordinates, in 2D space you'd only need too, in 11D space you'd need 11.

Also for the "time is the 4th dimension" business. Well, in space-time it is, since you need 4 coordinates to specify any given point in space-time, but that's specific to that particular 4D space and not universal.

For example it's possible to have a vector space with infinite dimensions - in mathematics.


PS: Feel free to correct me if I used a wrong expression somewhere, English isn't my native.

 

[Jonluw]

Dimensions are funny and I haven't really touched on more than the first three or four myself, but here is a nice video on the subject.
Ah, I see what you're saying in the OP now.
In the mentioned context, I think they mean "timelines" when they say "dimensions". Basically jumps between branches in the fifth or higher dimensions.

 

[PotluckBrigand]

Carl Sagan was the first person to explain it to me in a way I understood.

 

[Guffe]

Dimensions are funny and I haven't really touched on more than the first three or four myself, but here is a nice video on the subject.
Ah, I see what you're saying in the OP now.
In the mentioned context, I think they mean "timelines" when they say "dimensions". Basically jumps between branches in the fifth or higher dimensions.

AAAAARRRRGGGHGHGHHGHGHGHHHHH
MY HEEEAAAAAAAAAAD!!!
Make it stop pleaseee, noooooooooo!!
*head explodes*

 

[Aussie502]

Dimensions are funny and I haven't really touched on more than the first three or four myself, but here is a nice video on the subject.
Ah, I see what you're saying in the OP now.
In the mentioned context, I think they mean "timelines" when they say "dimensions". Basically jumps between branches in the fifth or higher dimensions.

AAAAARRRRGGGHGHGHHGHGHGHHHHH
MY HEEEAAAAAAAAAAD!!!
Make it stop pleaseee, noooooooooo!!
*head explodes*

That is actually one of my favourite videos on Youtube, It's what makes me love everything about physics

 

[CrimsonBlaze]

I might be wrong about this, so please feel free to correct me. I don't mind.

A dimension is essentially a unique plane of existence. A dimension is confined to its own set of rules and laws of nature that might conflict, or be completely unique, to those established from other dimensions. These dimensions can contain life and physical elements or be completely void.

Dimensions are not to be confused with an alternative time line (as they focus on a relative time and place in a given dimension) or an alternate universe (which focuses on different outcomes within a given dimension).

 

[Aidinthel]

*snip*

That is how the word is often used in fiction, but it's important to remember the real-world definition as well, in which the three visible dimensions are length, width, and height.

 

[CulixCupric]

snip

a line is a one dimensional object, and i am sure the 4th dimension is time, represented with a time-line. Also, I've never read flatland (I know it's a book), is it mathematics, psychology, and political satire?

EDIT: there are at leas 16 defined dimensions. I'll try to find the names.

height, width, depth, time, gravitation/electromagnetism, rest are string theory/quantum pockets and hypothetical theorems, the 11th being M-Theory.

 

[CAMDAWG]

EDIT: there are at leas 16 defined dimensions. I'll try to find the names.

height, width, depth, time, gravitation/electromagnetism, rest are string theory/quantum pockets and hypothetical theorems, the 11th being M-Theory.

Source please?

gravity/electromag are not dimensions. They are forces that may or may not be slightly different versions of the same thing, that operate within physical dimensions. Also, M-theory is not the "11th dimension" but rather the name given to a "theory" in physics that posits 11 dimensions. I am unaware of anything that predicts 16 dimensions. Bosonic string theory requires 26, but it's been superseded by other string theories.

Additionally, as Vegosiux said, the dimension of a vector space is simply the number of coordinates required to fully describe a point. Time is not "THE fourth dimension", merely the fourth dimension in the vector space that is four dimensional spacetime, but this is only because there are only 3 spatial dimensions we are aware of. So working with the fourth dimension as another spatial dimension like Sagan does is not an issue.

 

[Zack Alklazaris]

Ypu want to learn about strange dimensions looked up "M" Theory (The theory of Everything)

[link]http://en.wikipedia.org/wiki/M_theory[/link]

[In theoretical physics, M-theory is an extension of string theory in which 11 dimensions are identified. Because the dimensionality exceeds that of superstring theories in 10 dimensions, proponents believe that the 11-dimensional theory unites all five string theories (and supersedes them). Though a full description of the theory is not known, the low-entropy dynamics are known to be supergravity interacting with 2- and 5-dimensional membranes.

This idea is the unique supersymmetric theory in eleven dimensions, with its low-entropy matter content and interactions fully determined, and can be obtained as the strong coupling limit of type IIA string theory because a new dimension of space emerges as the coupling constant increases.]

 

[Fishyash]

Since I can't come up with a real answer, I am just gonna drop this here.


I personally found it pretty funny.

 

[PotluckBrigand]

snip

a line is a one dimensional object, and i am sure the 4th dimension is time, represented with a time-line. Also, I've never read flatland (I know it's a book), is it mathematics, psychology, and political satire?

I'm glad you asked that, because I didn't know the answer. I had only heard the name "Flatland" in reference to a book once or twice, and I assumed they were unrelated.

As it turns out, they are not! Flatland by Edwin Abbot Abbot (DOUBLE LAST NAME! WHAT DOES IT MEAN!?) is indeed apparently a book from 1884 about a square who is visited by a sphere who tries to convince him that there are more than just two dimensions, but he takes it as an affront to his sensibilities because he can't conceive of anything outside of his own reckoning. The sphere takes him to the first dimension to try and prove this point, as the people in the first dimension are just as unable to believe in the existence of the second dimension.

Parts of the book are intended to be direct social satire regarding the class and caste system of Victorian England, and it seems really interesting and funny. I've never read it, but now that I know about it, I fully intend to. (Admittedly, while I love reading, I'm not a massive fan of stuff from the 1800s... it tends to sound very dry to me, and the excerpt on Wikipedia was no exception).

But yes, apparently Sagan took his analogy pretty much part and parcel from the Flatland novel, but I'll let him have it since Cosmos rocked so fucking hard.

 

[CulixCupric]

But yes, apparently Sagan took his analogy pretty much part and parcel from the Flatland novel, but I'll let him have it since Cosmos rocked so fucking hard.

Sagan wrote the foreword for the book.

 

[Some_weirdGuy]

Pretty sure dimension is a homonym.