7 Match the words a-g and their synonyms 1-7.
a. an expansion
1. a crisis
b. a curvature
2. an enlargement,
growth
c. to verify
3. a swing, variation
d. to encompass
4. bending
e.
a blunder
5. to affirm, prove
f.
a fluctuation
6. a fault, mistake, slip
g- a big crunch
7. to include, contain
4 0 )
8 Read and complete the text with the following
sentences.
1. Adam Reiss was quite surprised looking through
the results — the expansion of the universe was not
decelerating, but accelerating — it was expanding
faster and faster!
2. However, in 1922 Friedmann published a paper
where he used Einstein’s original equations
without the cosmological constant term to show
that the universe must be dynamical.
3.
It is known that Einstein showed,
in his theory
of general relativity, that gravity is due to the
curvature o f spacetime.
4.
If the density were above a critical density, the
universe would continue slowing down in its
expansion due to the gravitational attraction of
the galaxies for each other, and the whole universe
would collapse in a big crunch at some future time.
9 Read the statements and decide if they are
true (T) or false (F).
1. In the theory of Einstein the gravity owes to the
curvature o f space
F
2. The source of gravitational field had to include
pressure and mass-energy density.______
3. Einstein proved that exactly pressure caused
spacetime to b en d .______
4. The gravitational repulsion cannot influence the
universe expansion.______
5.
The destiny of the universe
could be related to a
slowing down of the expansion ra te ._______
Text by J. Richard Gott (an extract)
The 2011 Nobel Prize in Physics has been
awarded to Adam Riess, Brian Schmidt, and Saul
Perlmutter for their discovery o f the accelerating
expansion of the universe. It is one of the times
when astronomers have won the Nobel Prize in
Physics. What does this discovery mean? Why
is the accelerated expansion o f the universe so
important? a ) ________________ He predicted that
the Sun should bend light rays from distant stars
passing near it. This effect was observed in 1919 and
Einstein’s prediction was verified.
In developing his
theory, he realized that the source of the gravitational
field had to include pressure as well as mass-energy
density. This is encompassed in something called
stress-energy. When Einstein worked out the
equations, they showed how stress-energy caused
spacetime to curve. His equations guaranteed local
energy conservation - cosmological constant, b)
_________________It starts with a big bang and
expands.
Space itself expands - a remarkable
concept. Galaxies move apart as the space between
them expands. Einstein then called the cosmological
constant his “biggest blunder.” In 1981, Alan
Guth proposed a theory o f inflation noting that
there was a quantum vacuum
state with a positive
energy density and a negative pressure causing a
gravitational repulsion. The gravitational repulsive
1 2
Scale U p
effects of the negative pressure make the overall
effect of this vacuum energy density and vacuum
pressure repulsive. It is an accelerated expansion.
The universe doubles in size every 10-35 seconds.
Eventually, the quantum vacuum state decays,
dumping its energy into the form of thermal radiation
- and the big bang Friedmann model takes over, c)
_______________ If the universe was below that
critical density, it would continue expanding forever.
The fate o f the universe could thus be determined
today by measuring how fast the expansion of the
universe was decelerating - how fast its expansion
rate was slowing down.
Two teams led by Saul
Perlmutter and Brian Schmidt set out to measure the
deceleration of the universe, d ) _____________ The
most likely explanation was that old cosmological
constant term of Einstein! The two teams came to
the same conclusion and reported their results in
1998. As the universe expands, dark energy stays
at nearly constant energy density and, as the matter
in the universe thins out, the dark energy begins to
dominate. Once that occurs, the universe goes from
an expansion that is slowing down to an expansion
that is becoming faster and faster.
In the future
we expect the universe to begin to double in size
approximately every 10 billion years.
Do'stlaringiz bilan baham: 
