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A word about parallax method :
This method was introduced by the german Bessel. Left, the
orbit of the Earth. S : the sun. s : a star.
From two opposite points of view, on the Earth's orbit ( T1 and T2 corresponding
for example to July to December) the star s occupies two different positions,
with respect to very distant stars, forming the background.
The astronomer may compute the angle D
q and compute easily the distance Dto the star,
using :
(108 ter)
The problem of the early universe.
Consider a time close to the so-called "origin" : t =
0
Suppose a particle, at this "very beginning of the universe"
a test-particle emits an electromagnetic wave, expanding at light veolocity
c. After a time c, this wave is a sphere whose radius is ct. One uses to call
it cosmological horizon. To be "informed" by a particle, a neighbour one must
be located in its spherical horizon.
The expansion dilates the cosmic "material", space. One
can consider two particles which are comobile which "move with space".
Call R(t) a characteristic length describing space dilatation.
(109)
It may represent the distance between these two particles.
If we compare R(t) to ct we get the figure (110) :
(110)
If t < th the radius of the spheric horizon is smaller
than the mean distance between two neighbour particles. They cannot exchange
anything ( energy, information ), they ignore each other : a fully autistic
universe, shown on figure (111).
When t > th the situation changes. The particles can communicate
for ct >> the mean distance between them.
t < th corresponds to primeval universe. The 2,7°
Kcosmic background radiation ( cbr) is the fossil image of this primeval
universe, which appears remarkably homogeneous. Why ?
If the air you breath is so homogeneous it is because
it is collision dominated. No important temperature gradient could stay a
long time, on short distance. Collision would smooth it quickly.
If you talk the same language it is because your ancestors
have talked a lot, together. Why the components of this primeval universe
look so similar when "they did not talk together in the past ? ".
The answer today is called inflation, Russian Linde's
theory. It is equivalent to give to the primeval universe some sort of super
cosmological constant, varying in time, some sort of repulsive property of
vacuum, which causes a fantastic expansion.
In :
J.P.Petit & P.Midy : 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. Geometrical Physics A, 6,
march 1998
the reader will find an alternative possible explanation.
The problem of the origin of time.
t = 0
`What does it means ? Does it make any sense, "close to
the origin" ?
When we go back in the past, the temperature of the cosmic
fluid grows and grows. The thermal velocity of "non zero mass particules"
grows too and tends to c when the temperature tends to infinite.
The non zero-mass particles own a "proper time" :
(112)
which depends on their velocity v, on the ratio v/c. When
v tends to c the proper time gets frozen. How can we imagine a clock in such
conditions ?
We see that the Standard Model is far from perfect, to
answer all questions ( this is not an exhaustive analysis).
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In the following we will present personal works. We
need to introduce first some geometric concepts, on which the job will be
setlled.
