Matter
ghost-matter astrophysics.3 :
The
radiative era : The problem of the "origin" of the universe.
The problem of the
homogeneity of the early universe.(p6)
Fig. 8
: Compared evolutions of temperatures.
- The problem of the origin
of universe.
Corresponding to that new description
of the radiative era, the entropy, as shown in former papers ([4], [5] and
[6]) is no longer constant.
(77)
For detailed calculation, see reference [6]. As shown in it that former paper
if during that radiative era the entropy is chosen as chronological parameter
the metric becomes conformally flat :
(78)
The origin corresponds to s =
- ¥
. Notice that s, the entropy per
baryon, identifies to the so-called "conformal time" Log t. With that new
time-marker the "initial singularity" disappears.
Looking back in the distant past
(early universe), one gets difficulties to define a clock, in order to measure
time, for all the particles run at relativistic velocities. It becomes questionable
to conceive a cold clock. Consider a system of two masses orbiting around
their common center of gravity :
Fig. 9 :The basic clock.
One assume that this clock is
not destroyed during the expansion process and calculate how many turns occured
in distant past (from t
= tcr to hypothetic origin of "cosmological time" t = 0). From above :
(79)
R »
t 2/3
G »
t - 2/3
m »
t 2/3
The orbitation time, the period
of the clock, corresponds to
(80)
The number of turns is :
(81)
(which tends to infinite when
t1 tends to zero). Surprizingly, we refind
the entropy per baryon s . If a rotation of the above system is considered
as an event of the evolution of the Universe there are an infinite number
of events between today and the epoch defined by the time marker t = 0.
Compare the universe to a book,
telling a story. The time is the width of the book. On would like to reach
the first page to read what the author�s purpose. Then we try to flip back
through the pages of the book. But the pertinent question is not the width
of the book but how many pages it owns. A page is an event. Acoording to this
new definition of time, when we flip back the pages, they become thinner and
thinner : the book owns an infinite number of pages, so that reaching the
preface becomes hopeless.
- An alternative to the
inflation theory.
Classically this the cosmologic
horizon His defined as ct , where c is considered as an absolute constant.
It rises a paradox as the primeval Universe is very homogeneous (cbr or cosmic
background). If we compare any characteristic distance R(t) (for an example
the mean distance between particles), with the horizon H , we get :
Fig. 10
: Comparizon of the evolution of the characteristic length of the Universe
with the cosmological horizon
in an Eintein-de Sitter model.
In the present model the cosmological
horizon becomes the following integral :
(82)
Fig. 11
: Comparizon of the evolution of the characteristic length Rof
the Universe with
the cosmological horizon, in
radiative era : same variation in time.
We get horizon H(t) »
R(t) during all the evolution of the universe, so that its homogeneity is
ensured during radiative era. This is an alternative to the theory of inflation,
(whose only today�s justification is the present homogeneity of the primeval
universe).
