sci.physics.relativity

"Jean Paul" wrote in message
news: @ ...
:> : >
: > : > R^2 = (ct)^2 + (ix)^2 + (iy)^2 + (iz)^2 = (ct)^2 + (ir)^2
: > : >
: >
: > The distance from the centre to the surface of a hypersphere.
: >
:
: Ok. That makes sense, mathematically anyway.

No it doesn't.
2AB/(t'A-tA) = c (Einstein),
the light has to go back to the centre to qualify c, so the radius is twice
the radius.


: So then the point
: (x,y,z,t) is at a distance R from some origin where that hypersphere
: is, where the values 'x', 'y' and 'z' are mapped to the axis X, Y and
: Z respectively of the Space dimensions, and the value 't' is mapped
: onto the Time axis. Cool.

Not cool. You can't go backwards in time.



:
: I understand why Einstein (or whoever else) came up with that formula
: because mathematically, it follows the same form as the one for the
: Space dimensions:
: x^2 + y^2 + z^2 = R^2
: *except* that in that formula, R is a distance in the same Space
: dimensions as x, y and z whereas in the formula
: R^2 = (ct)^2 + (ix)^2 + (iy)^2 + (iz)^2
: R is the *time* value T (as you confirmed below). It does not reflect
: anything about the Space dimension where (x,y,z) is. It's like that
: the distances in Space are irrelevant. One would think that the R
: should be some value where both time and distance units are involved,
: no? This formula confuses me.

That was the idea. As long as you are confused, Einstein wins.



:
: > : The
: > : (vt) is distance on a Space axis, say x, so it comes to: T^2 + x^2 =
: > : (ct)^2, or T^2 = (ct)^2 - x^2 = (ct)^2 + (ix)^2.
: > :
: > : So does the R mean the same as the T? So then R is 'distance' in the
: > : Time dimension... is that correct?
: >
: > Supposed to be, except Einstein and Minkowski were jokers and idiots,
: > not mathematicians.
: >
: > : Another thing. The fact that the imaginary number 'i' appears in the
: > : Space dimension should not be taken to mean that the Space dimensions
: > : are imaginary in the sense that they do not exist. They do exist:
: > : there are three such dimensions. That is clear. What is imaginary are
: > : the Space axes. They are imaginary in the same way that a grid on a
: > : city map are imaginary. Having said that, in the formula, the time 't'
: > : is not imaginary, so then the Time axis is real, although we cannot
: > : see or feel it. Am I understand this correctly?
: >
: > I can go back to where I was. That's imaginary, because I travel
: > a negative distance. I seem to be having difficulty going back to
: > when I was, but that was real enough.
: >
:
: I see what you mean, and I was thinking the same too, except that the
: minus sign in the formula
: R^2 = (ct)^2 - x^2 - y^2 - z^2
: does not mean a negative direction of movement in space. When I go
: back where I was, it is the 'x', 'y' and 'z' values that become
: negative, right?

Of course. So make t negative too, then you can go back to when when you
were.
All you have to do is write -t and bingo, mathematics makes physics work.
See axiom 4 of this:
/
Note: There EXISTS...

Einstein failed mathematics in school, in 1895 he failed an examination that
would have allowed him to study for a diploma as an electrical engineer at
the Eidgenössische Technische Hochschule in Zurich (couldn't even pass the
SATs).


: In any case, that formula does not feel to have a physical reality. No
: wonder that the 'i' number is involved! ;-)
:
: Jean