Are there other dimensions ?

[Aryan]

We all know that there are four dimensions x,y,z,time
Perhaps new theories can create more dimensions (eg.: string theory , 11 dimensions)
But all dimensions either have units of length or time
x=length=y=z,
Isnt there some new dimension based upon some new property ?

[Almaviva]

Time and length are too closely related under relativity to be considered completely different. One meter of time is the amount of time is takes light to travel one meter. Distances will be measured as different for different observers moving at different speeds, but the "spacetime interval", x^2+y^2+z^2-t^2 is always the same.

Another cool thing is that a baseball travelling in a parabola looks to be on a far curvier path than a bullet, which might fall an inch or two before it hits its target, but if you measure their curvature *including the time dimension* it is the same, because the baseball takes a much longer time to follow its path. And in fact, gravity can be thought of as this curvature in space-time.

[Niflheimian]

Isnt there some new dimension based upon some new property ?

I wouldn't know... But even if there were more dimensions, it's unlikely we'd be able to perceive them.
What a pity...

[indczn]

The language i need to answer your question slips my mind. Maybe I will recall in the morning, but i do believe its likely there are more curled dimensions.

[Hypnos]

In string theory (and related theories), dimensions beyond 4 are "compactified" -- wrapped up in hyper-toroids and what not.

[KentOhio]

I was just thinking... what if gravity can be a dimension? Things can exist with and without gravity. Maybe dark matter, then, is ''stuff'' that doesn't exist in any other dimension than gravity.

[Hypnos]

I was just thinking... what if gravity can be a dimension? Things can exist with and without gravity. Maybe dark matter, then, is ''stuff'' that doesn't exist in any other dimension than gravity.
See above.

[jimkopelli]

Can you think of anything that can exist without gravity? Even if it's lightyears away from anything else, there is still a small amount... plus, any material object will have some small amount of gravity that it creates. What's that quote... "If you pluck a flower, you move the farthest star..."

[KentOhio]

Well, energy can exist without having gravity

[jimkopelli]

What kind of gravity? How would you measure the energy unless it acted on something?

[Aryan]

KentOhio has got a point.
In fact I was thinking like an object which cannnot be detected by our instruments but still exists within our own domain must have some other attributes (dimensionally).

I know there are eleven dimensions and so on in string theory But i said dimensions always have the attributes of length and time and mothing else (eg. Gravity or whatever )

[Hypnos]

Well, energy can exist without having gravity
Not according to general relativity, nor in any of the string models I have seen.

[jimkopelli]

The thing with theoretical physics.. is that it's theoretical. String theory is the best they can come up with at the moment, and it seems to fit all the facts that they know of. However, they still don't have enough empirical evidence to prove squat.

[Hypnos]

The thing with theoretical physics.. is that it's theoretical. String theory is the best they can come up with at the moment, and it seems to fit all the facts that they know of. However, they still don't have enough empirical evidence to prove squat.
It does fit with known facts, and is moreover plausible.

Some of the stuff bantied about here is just plain wrong.

[jimkopelli]

It's plausible that they faked the moon landing. Have you seen any rocks? Did you go? Videos and rocks are easy to fake. Have you seen the other eight dimensions neccasary for string theory to work? Never mind that they're "really small and twisted up." I think that it's possible, sure... but cutting-edge physics people have been wrong before.

[Hypnos]

It's plausible that they faked the moon landing. Have you seen any rocks? Did you go? Videos and rocks are easy to fake. Have you seen the other eight dimensions neccasary for string theory to work? Never mind that they're "really small and twisted up." I think that it's possible, sure... but cutting-edge physics people have been wrong before.
String theory fixes many of the intransigent problems of field theory (esp. w.r.t. gravity), without creating anymore physical problems, and exhibits the beauty and economy common to all successful physical theories -- so it's not obviously wrong, and probably worth our time.

Fake moon landings are not.

[Aryan]

Thoeries are just intstruments.
They don't explain realities.

[Boozer]

I thought that's exactly what theories were for, to help explain reality. It's not like you're going to see them yourself. It's obvious that for whatever reason we've evolved as 4 dimensional beings (including time as a dimension). In order to understand anything beyond what our senses can tell us we need scientific theories to fill in the gaps.

And to answer your question, in my opinion there are other dimensions. Not only because of string theory, but just aesthetically is has always seemed to me that reality contains a lot of symmetry. I don't find it hard to believe that there is more to this world that what we can sense.

[floyd]

i was reading up on this lately and some think that multi-dimension theory is just a trendy theory, any question string theory can answer can also, apparently, be answered by the xyz-time dimensional model.

[Boozer]

For me the biggest appeal of string theory is the possiblilty of combining relativity and quantum theory in a system that makes sense. I think if string thoery didn't bring something new to the table people would be all too ready to dismiss it. And yeah it is getting trendy. I'm not a physicist, how else would I know any of this stuff if it hadn't already leaked into the mainstream, that doesn't make it wrong.

[Google Monster]

I can't see clearly how time is a dimension.

[Hypnos]

I can't see clearly how time is a dimension.
In relativistic kinematics, the speed limit at c means that when you change intertial frames of reference, time must be shifted as well as space -- this makes it dimensionful.

There are a number of good tutorials on the web explaining this process.

[Boozer]

I can't see clearly how time is a dimension.
In relativistic kinematics, the speed limit at c means that when you change intertial frames of reference, time must be shifted as well as space -- this makes it dimensionful.

There are a number of good tutorials on the web explaining this process.

I thought I understood it... no I lost it

:D

[Kljoki]

Is it possible that space and time are different kinds of dimensions?


There are 3 space dimensions we perceive. Time is assumed to be the 4-th dimension. But if there were 2 dimensions we would still perceive an additional time dimension. A sense of change. Same analogy goes for n number of dimensions.



Could dimensions be like particles with different kinds? Where our space dimensions are intertwined with time dimensions.


Could our dimensional existence with space and time be a dimensional complex particle of sorts?