Is it pointless attempting to conceive the notion of higher dimensions?

[forked brain]

If I understand the theories correctly, then yes within the theories - but only because they treat the observed dimensions as abstractly as the others.

Which may (I intiut) have some connection with the fact that they're rather abstract theories - I recall reading that no-one has come up with a prediction that could be used to construct an experiment (necessarily taking place within the observed dimensions ) to distinguish one string theory from another.



Clearly not the same, almost by definition of our having evolved in a four-dimensional world.

Evolutionary psychologists (ptui, but they're useful for this sentence ) would say that our intuitive grasp is rooted in the constant need to decide whether that is lunch or whether it's looking at us as its lunch.

Certainly our intuitive grasp leads to, er, intuitions that Newtonian physics says are not what's "actually going on".

It's fuck-all use dealing with either the Planck scale or the whole-universe scale, which is what your 10- and 11- and 26-dimensional theories are doing.

Nobody yet on this thread has actually defined 'dimensions', for they in their self are timeless, nah?

 

[laptop]

Nobody yet on this thread has actually defined 'dimensions',

In mathematical descriptions, in this context, a dimension is an element of the "vector" that describes a particle's current location in space-time.

In four-dimensional space-time these can be labelled "up", "right", "forward" and "later".

The database example on the previous page describes points in the space of all possible curriculæ vitorum in terms of "first name", "family name", "mathematical expertise" and so on. These are dimensions of that space.

for they in their self are timeless, nah?

Hippy.

As noted above, time is a dimension in the Einsteinian universe.

* Awaits firing of Donna Ferentes' infallible Latin-error-detector *

 

[forked brain]

space-time.

In four-dimensional space-time these can be labelled "up", "right", "forward" and "later".

Please tell me you're kidding

 

[TeeJay]

Certainly our intuitive grasp leads to, er, intuitions that Newtonian physics says are not what's "actually going on".

Our system of visual processing can even get confused with optical illusions (eg seeing things move when they are no, seeing weird colours, seeing things as the wrong length etc). Nice examples and scientific explanations for each one here: http://www.michaelbach.de/ot/

 

[rich!]

where do we get dimensions from? in particular, how do we determine how many there are?

well, the trick mathematicians use is to find the smallest number of directions you need to get everywhere.

On a line, there's one direction (but you can go forwards and backwards).

On a piece of paper, there are two directions. If you only use one direction, you can't get everywhere.

In a room, there are three directions.

In General Relativity, there is another dimension that goes in an imaginary direction very very quickly, but let's not go there.

In string theory, there appear to be 7 or 8 dimensions "rolled-up" - so we can't actually move along them, but they exist.

Then there are the surfaces of objects. A sphere has a 2-dimensional surface. The next object "up" has a surface that is a sphere.

Then people start to try and count the dimension of complex objects, and they find things like coastlines and Sierpinski triangles and Mandelbrot sets that have dimensions like 1.567.

After that, it got too weird for me, and I went to study computers instead.

 

[forked brain]

Our system of visual processing can even get confused with optical illusions (eg seeing things move when they are no, seeing weird colours, seeing things as the wrong length etc). Nice examples and scientific explanations for each one here: http://www.michaelbach.de/ot/

Sorry dude, I haven't looked at you link. Only because you could have 'scientific' background information. Is 'science' three dimensional?

 

[laptop]

Please tell me you're kidding

Not in the slightest.

You can give them other labels. But these are relevant labels for any given observer to use.

And the whole point of Einsteinian space-time is that there is no priviliged dimensional framework.

 

[forked brain]

In General Relativity, there is another dimension that goes in an imaginary direction very very quickly, but let's not go there.

Great post dude, this is your best bit

 

[rich!]

Great post dude, this is your best bit

I was thinking about trying to explain how metrics and dimensions interact.

basically, in a well-ordered space (like a piece of paper) you can measure the distance between points. There's a matrix you use to do this.

In the spaces we're used to, it looks like
1 0 0
0 1 0
0 0 1

In General Relativity, it looks more like
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 -c2

in other words, a difference in one of the dimensions makes distances shorter rather than longer...

After that, black holes seem quite reasonable.

 

[forked brain]

And the whole point of Einsteinian space-time is that there is no priviliged dimensional framework.

Are you privileged? If I never knew mathematics, I'd say I have infinite dimensions

 

[laptop]

Are you privileged? If I never knew mathematics, I'd say I have infinite dimensions

Right now I'm rather privileged to be operating on half a bottle of surprisingly nice wine, and to be going to sleep right after this.

I really do hope you're operating on something more mind-bending and that you'll be sober by lunchtime.

 

[forked brain]

I was thinking about trying to explain how metrics and dimensions interact.

basically, in a well-ordered space (like a piece of paper) you can measure the distance between points. There's a matrix you use to do this.

In the spaces we're used to, it looks like
1 0 0
0 1 0
0 0 1

In General Relativity, it looks more like
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 -c2

in other words, a difference in one of the dimensions makes distances shorter rather than longer...

After that, black holes seem quite reasonable.

No offence dude, but you're talking about three dimensions that can't move, then sling in time.

The best definition of time is:

velocity divided metres

 

[forked brain]

Right now I'm rather privileged to be operating on half a bottle of surprisingly nice wine, and to be going to sleep right after this.

I really do hope you're operating on something more mind-bending and that you'll be sober by lunchtime.

I'd say have a pleasant time, but what is it

Later maybe, but what's that

 

[TeeJay]

Sorry dude, I haven't looked at you link. Only because you could have 'scientific' background information. Is 'science' three dimensional?

Sorry I don't understand what you are asking here.

 

[forked brain]

Sorry I don't understand what you are asking here.

You were referring to optics, I was referring to time. You can only measure time if you're three dimensional, it's a law

 

[TeeJay]

Sorry I still don't understand what you are asking. Look at the link if you want to. My point about optical illusions is that the process which the eyes and brain use to construct a "3d" world from raw sensory input can get confused. There are various theories about why certain images confuse the eye/brain and this helps us realise that even basic dimensions are a kind of abstract concept used to process information rather than something we simply "see" directly and consistently.

 

[rich!]

No offence dude, but you're talking about three dimensions that can't move, then sling in time.

time doesn't move either.

The best definition of time is:

velocity divided metres

given that velocity is defined as metres divided by seconds, that's not a definition of time.

 

[forked brain]

There are various theories about why certain images confuse the eye/brain and this helps us realise that even basic dimensions are a kind of abstract concept used to process information rather than something we simply "see" directly and consistently.

I'm not arguing this, but how do you, as an individual, measure 'time'?

 

[forked brain]

time doesn't move either.

Why didn't i think of that

given that velocity is defined as metres divided by seconds, that's not a definition of time.

but if velocity is divided by metres, what then

edi: see what time does

 

[forked brain]

over a period of time

who's 'time'?

 

[J77]

I work in infinite dimensions

It's a challenge...

 

[Diem K]

I don't think it's pointless to try and concieve a notion of higher dimensions.

Mathematics has no problems with it and there is a possibility that they actually exist.

Unless the "curled up" dimensions uncurl themselves and humans evolve in parallel we will never be able to "see" or "understand" additional dimensions, however, we should do whatever we can to understand if/why they exist and what that means to the universe.

 

[J77]

The crux is that people understand spatial dimensions but mathematically this is the tip of the iceberg.

Euclidean dimensions are what most people think of and the fourth dimensional tesseract is an easy concept to grasp when extending from the cube - see the earlier Flatworld reference.

However, there are many more...

Also, when people are talking about the other dimensions "tightly curled up" - we're getting onto string theory here, right?

wiki

 

[EastEnder]

I don't think it's pointless to try and concieve a notion of higher dimensions.

Mathematics has no problems with it and there is a possibility that they actually exist.

Unless the "curled up" dimensions uncurl themselves and humans evolve in parallel we will never be able to "see" or "understand" additional dimensions, however, we should do whatever we can to understand if/why they exist and what that means to the universe.

I tend to agree with you, but the implication of what you're saying is that there is no point trying to understand extra dimensions on any tangible level.

My original query was really trying to ascertain whether the human brain can, or could ever, have a similar intuitive grasp of extra dimensions that it has of the usual 3 spatial dimensions. Obviously, these things can be understand via analogy, mathematical representations, and so on. But that is not how we understand the usual X/Y/Z spatial dimensions.

My supposition is that even if it's proven that there are extra dimensions, and no matter how much we learn about them, the human mind will never be able to comprehend them in anything more than a descriptive, rote based manner.

I can describe a point in 3D space using a variety of coordinate systems, I can draw it out on paper, I can explain the principles to others, but crucially I can also visualise the whole thing in my head - without ever needing to find any practical way of describing it. It's intuitive & innate, a product of growing up in a 3D world. No matter how much is ever discovered about extra spatial dimensions, I don't think it will ever be possible for the human mind to comprehend them in any genuinely tangible way.

 

[Blagsta]

do some ket

 

[Diem K]

I can describe a point in 3D space using a variety of coordinate systems, I can draw it out on paper, I can explain the principles to others, but crucially I can also visualise the whole thing in my head - without ever needing to find any practical way of describing it. It's intuitive & innate, a product of growing up in a 3D world. No matter how much is ever discovered about extra spatial dimensions, I don't think it will ever be possible for the human mind to comprehend them in any genuinely tangible way.

maybe we dont need to comprehend them in a tangible way. Like you say we inhabbit a 3d dominated space.

Einsteins "tangible" way of describing gravity is not really tangible. To explain that space-time is curved (but not curved in our 3 dimensions of space) is only an analogy and is not a tangible method of comprehension, its just a tool to help you think about it and visualise the impact which mass has on space.

The same would apply if some extra spacial dimensions were "found", all we would need to know is that at every position in space there are other dimensions which we can't probe at a human level.

Its no different than saying that space has a curvature in every position. I have no visual comprehension for the curvature of space caused by the mass of the earth, however, I do know the "feeling" of gravity.

If physics confirms extra dimensions they will therefore have physical properties/influences on what we experience (otherwise i doubt the extra dimensions will be found or suggested to exist!) therefore the resultant physical interaction with the extra dimensions will be the tangible method of comprehension (and proof!). This is where i think dark matter/energy are probably bound up in some way into the extra dimensions.

If if they are tangible in terms of physical explainations (like Einstiens space curvature) you still won't "see" them.

 

[Binkie]

Some of you guys are like dark age mystics - speculating about the existence of human constructs. They speculated on the properties of angels and the mind of god; you speculate on the 'existence' of 'a fourth dimension'. As the guy said - do some ketamine if all you want to explore is your own mind.

 

[EastEnder]

As the guy said - do some ketamine if all you want to explore is your own mind.

I've done more than enough ket to go exploring hippy, out of mind trips.

But that hardly addresses the question of whether the human mind is now, or will ever be, capable of understanding extra dimensions on any kind of tangible level.

 

[laptop]

I work in infinite dimensions

Um... what do you put in them?

If you have a space with a countable infinity of dimensions, is the number of integral-coordinate points in the space countable?

 

[Azrael23]

I think anyone can understand bands of vibrational frequency.