(1) |
Most people have learned at school that there is no solution for the square root of a negative number. However at the university you get taught that there is one, this one is not real , but still you can 'imagine' that there is a solution, which we call . This may sound strange and useless, however introducing this number gives enormous advantages for mathematics. Physics deals with quantities, which can be measured and are consequently real. However, in theoretical formulas or in theoretical calculations, we often use imaginary numbers.
Real numbers and imaginary numbers form the group of complex numbers. Mathematicians have derived a whole set of rules how to calculate with complex numbers. Some simple examples of calculations with complex numbers are the following:
(2) |
or a bit more complicated
(3) |
The proof of last expression requires a bit more advanced mathematics.
The reason to put it here is just to show the beauty of
some mathematical formulas with complex numbers.
It is quite surprising that the expression with all those
complicated numbers and has such a simple result.
More information about imaginary numbers, real numbers, rational, irrational numbers, etc., can
be found
here or
here.
A slightly different interpretation of imaginary numbers can also be found in literature:
Waterson Calvin and Hobbes .
(4) |
The hyper-complex numbers are extremely useful in Einstein's theory of Relativity. Here I will show you a single result to prove this. Einstein improved the classical mechanics theory, by a reformulation of the basic physical laws, known from Newton's Philosophiae naturalis principia mathematica. The rules formulated by Einstein are independent on the inertial system of the observer. Basically this means that the laws of physics noticed by you should be always the same, no matter if you are standing still, are in a plane, space shuttle, on Earth or on Mars. The spatial and time observations of a certain event in space (e.g. explosion of a neutron star, collision between two black holes etc.) can differ for two observers, who are at different places and at different times somewhere in the universe.
However there are quantities
which they can both observe and which are exactly the same for both. The
event in space can be described with a
so called position four-vector , in which time and space are
combined into a four dimensional superspace: the
Minkowski-space
(5) |
(6) |
The first part deals with
contravariant and covariant representation of the position four-vector, but
I will not bother you about this here.
What is important, is that is approximately the length of the
four-vector , but not completely, as you need to put the plus and
minus signs on its right position. However it would be much easier
if we really could think of as the length of a four-vector.
That is possible if we would have used the correct position
four-vector!. With the help of hallucinary numbers, we can now define a new position four-vector:
(7) |
(8) |
This is just one example, but all physical formulas become much more simple
and more elegant when we use hallucinary numbers. No need for covariant
and contravariant representations anymore. The elegance of the new
formulas proof that this is the only and true way how we should think.
There is no other way, then
that the four-vector postulated in eq. (7)
is the only and true representation of space and time and is thus favourable
to the old position four-vector of eq. (5).
One striking and inevitable conclusion from eq. (7) is:
Time is the hallucinary dimension of space!!
I think, subconsciously, you were all aware of that, but finally there is scientific proof!!