# N-dimensional time

#### goldeng8

The idea of 3,4,....11 dimensional spacetime has been around for a while.

This always means (N-1)-dimensional space, with the usual addition of time as one dimensional.

Are there any serious thoughts on the possibility of M-dimensional time, and what this would mean in the physical world?

(Maybe this is somewhat of a parallel discussion to the earlier post of 'imaginary time' here, but I decided to start a new thread anyway)

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#### MathematicalPhysicist

Gold Member
F theory

there's a theory that adds another time dimension and it's called f theory.
the developer of theory is cumrun vafa.

#### quartodeciman

Here is something to contemplate.

The four dimensions of basic relativity are ct, x, y, z. Though often called one time dimension and three space dimensions, in fact, 'ct' is a space dimension (speed times time). A famous relativity space invariant equation is

s2 = - (ct)2 + x2 + y2 + z2

Now represent this by substituting uniform variable names from

x0 <== ct
x1 <== x
x2 <== y
x3 <== z

Here is the result.

s2 = - x02 + x12 + x22 + x32

Every term is a space term.

But it can all be rewritten in time dimensions.

&TAU <== is/c
t0 <== t
t1 <== x/c
t2 <== y/c
t3 <== z/c

The result.

&TAU2 = + t02 - t12 - t22 - t32

This is a relativity time invariant equation using four time dimensions.

#### Doctor Luz

This has few to be with the subject however, when I was 'studiying' Quantum Mechanics, one day my teacher told (looking at me when I was about to fall asleep) that the time was not a dimension, it was a parameter. I never understood what he was talking about that day.

#### Tyger

Originally posted by Doctor Luz
This has few to be with the subject however, when I was 'studiying' Quantum Mechanics, one day my teacher told (looking at me when I was about to fall asleep) that the time was not a dimension, it was a parameter. I never understood what he was talking about that day.
Your teacher was right. Space has three degrees of freedom, that is what a dimension is, a degree of freedom. But you can't move around in time the same way, if you move around in space a lot you change your movement in time some, but bsically you move through time at the same rate, whether you want to or not.

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