It is known that the
universe after the Big Bang has undergone swift increase, during which its
volume increased to a staggering 80-degree! Universe and then continued its extension,
but the recent increase in size was accelerated, resulting in a region of the
universal signal extended outside.
For "writing"
a detailed history of the expansion in the boss method, called "baryon
acoustic oscillations-oscillations" (BAO). Physicists call ordinary
baryons and all the usual matter.
Quite unexpectedly they
found that the galactic density peaks defined sound pressure, hence the name of
the method.
Like any explosion, the
Big Bang, which led to the birth of the universe, "roared" at full
power. Propagation of sound waves that long blast occurred in a hot source
plasma "soup" in which any regular density peaks. After about 380
thousand years after the Big Bang "soup" cool enough to slow down as
a result did the first proton-electron pairs, or hydrogen atoms. Invisible dark
matter, too, was part of the broth and the photons of light have gone their own
way.
It can be assumed that
the recession of galaxies has until recently been fairly uniform, so the
distance to the object, and also speaks about his age. Helps and redshift of
light waves, telling us about the age of a particular corner of the universe.
The physics of this unique phenomenon is the fact that the expansion is
proportional to "stretch" of the space: the same light wavelength
increase in its path as it contributes to tension and an increase in length
respectively. Red edge of the visible spectrum has wavelengths nearly half
times more than the blue.
With Bossi have already
precisely determined the position of 327,349 of massive galaxies with a
redshift of 0.7 that is still very close to the Earth. The mean bias is 0.57,
which corresponds to a distance of 6 billion light-years. The achieved accuracy
of the range of 1.7%, or about 2 megaparsecs. Anything like optical astronomy cannot
give.
BOSS can also talk
about violations of the red shift, which the researchers hope to test gravity.
Tests show the speed of joint motion galaxies neighbors, which leads to the
formation of clusters. It is possible that it will be another confirmation of
Einstein's general theory of relativity.
Now the definition of
the expansion depends only on the definition of the red shift, which is the
less accurate the farther away the deleted object. Statistical analysis of the
red shift of hundreds of thousands of galaxies revealed the presence of local
variations of the Hubble expansion rate, as well as indicators of gravity at a
distance of 100 million light-years, more accurate than those obtained by measuring
the distance from the Earth to the Moon.
"Maintenance"
in the space provided does not mean the death of ground-based telescopes. On
the contrary, the data are compared with those obtained by the Sloan telescope
with a mirror diameter of 2.5 meters, which is located in the town of Apache,
New Mexico. Interest to the telescope increased particularly when it installed
a new fiber spectrograph having a half more fiber than the previous versions,
to monitor it for the Galaxy.
In just 15 minutes of
observation telescope time to "cover" the three degrees of the sky,
while on thousands of fibers running from the focal plane of the mirror, the
computer is receiving digital information. The spectrograph is designed in such
a way that each of the fibers ensures a distant, but still bright galaxy that
has already "lit up" in previous cases. To increase the area of
monitoring and permit new spectrograph equipped with secondary camera
captures images in the red and blue spectral regions.
Of New Mexico, the data
being sent for treatment in Berkeley, not far from San Francisco. The
information is then used to generate new galactic catalogs describing today
more than a million of them. In March, reported the discovery of exotic, like
"Spider" and "Diamond". Bossi results are presented in two
major reviews that were published in the prestigious journal Monthly Notices of
the Royal Astronomical Society.
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