Fourth dimension=time?

[Moontanman]

Is time really the fourth dimension? If a 6" line has an infinite number of points, and a 6" square contains an infinite number of 6" lines and a 6" cube has an infinite number of 6" squares doesn't it follow that a 6" hypercube has to have an infinite number of 6" cubes? Does this analogy hold up to our idea of time? I don't think so, could time have nothing to do with dimensions, could it be a process, not a thing?

[freeztar]

Originally Posted by Moontanman

Is time really the fourth dimension? If a 6" line has an infinite number of points, and a 6" square contains an infinite number of 6" lines and a 6" cube has an infinite number of 6" squares doesn't it follow that a 6" hypercube has to have an infinite number of 6" cubes? Does this analogy hold up to our idea of time?

I don't think it does. Extending the known, and spatial, three dimensions to posit a similar characteristic in the fourth does not tell us about time. Indeed, it does not tell us about the fourth dimension. A hypercube is a visual and conceptual aid. It is not the fourth dimension (the map is not the territory). It's a way of envisioning the fourth dimension using the only dimensions conceptually available to us.

I don't think so, could time have nothing to do with dimensions,

Well, if you consider spacetime, time has everything to do with dimensionality, with space and time occupying separate, yet intertwined, dimensions..

could it be a process, not a thing?

Certainly. It would actually be hard to argue that time *is* a thing.
If you haven't already seen it, I recommend the following video for a look at scientific explorations into the nature of time.

YouTube - 1of5 -- Brian Cox - What is Time

[Moontanman]

I think the idea that time is a dimension is flawed, if we lived in a four spatial dimensional universe I think we would still see time, probably as a 5th dimension but we would still be wrong. the idea of a hypercube is like saying a cube is just six two dimensional squares. It ignores the real concept of an extra dimension. when you go up a dimension you gain an infinite amount of space compared to the lower dimension.

[arkain101]

Edited

What strikes me while reading this is the idea of something moving in the dimension of time (regardless of the number you give it: 1st, 2nd, 3rd, 4th).

When we say an object moves, it is the same as saying the object has traveled in the 4th dimension.

Change and Time are intertwined concepts. However, if we consider change to occur, or time to flow in separate "chunks", by means of acquiring a specific state for a given position in space; ie, object @ state 1-position 1 , state 2-position 2, state 3-position 3. Then, this would suggest that time is not a valid dimension without a relative counterpart. That relative counter part would be memory.

In order for time to flow, which means, for any given state to have a connection to any other given state, it needs a relative item, just as a position of an object requires a secondary relative position for the "event" of "position" to exist.

This would mean that Time and Memory are linked. Noting that The medium of memory has remained undefined, but still realized.

To support these notions. Consider the differences of a spacial dimension and a time dimension. We can consider a 3 dimensional cube at a given state, at a given position. It does not demand memory, because one could say that it IS memory, such that, it is a state of memory. What we can see is that the difference between an object and a dimension (ie time) is that an object in a 'state' is full of valid relative counter-parts (formed out of other smaller divided states and positions). How I understand time is often conceived (or at least how you are conceiving it Moontaman), is that, it is conceived with the exclusion of a relative counter-part (an element of its own kind so to speak)

If spacial dimensions are valid via means of relative spacial points. Then should we not consider that time is only valid via means of memory points?

Earlier I mentioned that material was akin to memory and that time and memory are unified, when declaring time "flows". Which basically translates into the old space-time continuum. Space=memory=time.

The Term memory as I am using it can be thought of as simply representing a dimension. For example. Consider the Life of the universe. From beginning to end of this dimensions points A and B are trillions^ trillions of tiny tiny tubes which are to be considered as the view of a particles "life" seen in the dimension of memory(time). When we place slate in this dimension it represents a point in time. Moving this slate along, through the tiny tubes, creates events on the plate, the events determined by the orientation of the tubes. Orientation being, direction and size of the tubes (spirals and curls, narrows and buldges). So the dimension the tubes travel through is times dimension. The body itself is the memory(the connection of time points). The slate, well that is the present.

But this example is a manner of placing the medium of memory to the outter world.. such that it is a place "out there" , physical in some possible way, as opposed to the consciousness and applying memory within, which is a whole other story.

But I am not sure if you can escape the demand of memory, if something is also declared to have passed through the dimension of time, while upholding the notion that the universe flows, as opposed to pops in and out.

On the other hand, if the incentive is to uphold the notion that universe does not flow through a dimension of time, but rather pops in and out, and each pop is entirely disconnected from any previous or post pop, then in this case, memory or even time, would seem to me, to lack any importance.

[Haech]

But a hypercube does have an infinite number of cubes, and there are infinitely many expressions of the same cube at a given length of time. In any case, I always felt that treating time as a dimension is fairly straight forward and acceptable; that is not to say that time is the same thing as the x, y, z axis.

[maddog]

Originally Posted by Moontanman

Is time really the fourth dimension? If a 6" line has an infinite number of points, and a 6" square contains an infinite number of 6" lines and a 6" cube has an infinite number of 6" squares doesn't it follow that a 6" hypercube has to have an infinite number of 6" cubes?

Assuming that your coordinate space were using the Reals {R}, then yes, there would be
an infinite number of 6" cubes (uncountably so) within the hypercube. In fact for any number
of dimensions, there are an (uncountable) number of subspace objects (1-dimension lower)
within a given object for some space of dimension n. This is a property of the group
GL(g, n) for vector spaces.

Originally Posted by Moontanman

Does this analogy hold up to our idea of time? I don't think so, could time have nothing to do with dimensions, could it be a process, not a thing?

Your example above was a representation. Time as expressed in 4-d space {x,y,z,t}
is a representation. The value (coordinate) t is arbitrary. As such (using Reals) is
also uncountably infinite.

An important point here is we are currently speaking Mathematically and "Classically".
From the point-of-view (POV) of QM where coordinates can be discrete ("quantized"),
this can still be a large number yet finitely divisible. This would be so for time as has
recently been conjectured.

As representations go, time is not exactly the same as a space coordinate yet can be
transformed into one by multiplying c (velocity of light).

maddog

[LaurieAG]

Hi all,

I always marvelled at the intimate relationships between speed, acceleration and the distance travelled revealed through pure calculus proofs. All were based on the derivation of something with regards to time (delta t).

Surely, if time was the 4th dimension, this convention would have to be adhered to in all algorithms used, at least if calculus was going to be involved.

[buddyzen]

we have to remember also time is a man made thing and it does not actually exist so time can't be the 4th demention. People always have crazy talk about going back in time when the time itself is something that cant be touched or changed because once again it is just a measurment of the sun relation to where you are on the earth. Also people ask what was the beginging of the universe in my opinion it has always been here because there is no time involved with the universe only what we percieve involves time there never had to be a start..... so no i really don't think the fourth demension is time

[Pyrotex]

Originally Posted by Moontanman

I think the idea that time is a dimension is flawed, if we lived in a four spatial dimensional universe I think we would still see time, probably as a 5th dimension but we would still be wrong. ...

You're right. Time is not THE 4th Dimension.

There are three (3) spatial dimensions. If you have "time" to plot them.

Seriously folks, that's really the way it is -- BUT scientists and engineers often have need to plot the positions of events. Trouble is, the events don't always happen at the same time. Suppose we're plotting radar bounce events. We have this map, see, and on it we plot where our radar detected reflections. But some reflections happened before others, and this is important.

So, we arbitrarily, draw in a new "dimension" and we call it "time". Now we can plot where and when the radar reflections occured.

But the physicist says, "that's not good enough. My calculations have to involve the speed of the radar beam and its reflection (c), and the speed of the vehicle carrying the radar, and the speed of the target. Your arbitrary "time" axis isn't good enough for me."

So the engineers knock heads and come up with this: Let's turn our arbitrary "time" axis into a pseudo-distance axis. If we take the clock-time in seconds and multiply that by c, then that would give us units of distance. [ sec * m/sec = m] Now, to avoid this pseudo-distance axis being just some combination of the three real distance axes, we can also multiply it by i [the square root of minus one]. Our time-pseudo-distance (TPD) is now an imaginary number. And we all know how to do complex arithmetic!

And it worked! The physicist could now do his calculations and get the right answers.

And the years and generations went by until... folks actually begin to think that time was the "fourth" dimension. And then they had doubts. "Wait! That can't be right! Time isn't like the other dimensions at all! I can't see time or go back in time like I can, say, East-West!"

And they were right.

[freeztar]

Originally Posted by Pyrotex

And they were right.

You can't leave us hanging like that! What did they do about it?