The birth and the death of the universe
Introduction: Our understanding of how the universe has evolved is one of the greatest achievements of modern science. Decades of experiments and theories have allowed us to know what we do today. There are many explanations for our universe --- religious, astrological and philosophical, but in science, we accept only what is tested and proven by experiments or observation. Modern telescopes have detected light from galaxies that are far away. Satellites have detected radiation left by the creation of the universe billions of years ago. So, what are the theories of creation?
Theories of creation:
The Big
Bang Theory: This
theory is the most popular one and it talks about how the universe was formed
by a massive explosion some 14 billion years ago. At this time, space was
extremely hot and it took close to 3,00,000 years for the universe to cool down
by about 3,000 degrees. This cooling down also helped in the creation of
elements, as atomic nuclei could finally capture electrons to form atoms. The universe
was soon filled with clouds of hydrogen and helium gas, allowing stars and
galaxies to come together due to the force of gravity.
The
Eternal Inflation Theory:
This is an extension of the Big Bang Theory and states that the universe
expanded rapidly during a small period, in a process called inflation, and then
never stopped expanding! Even now, new universes are being formed.
The
Oscillating Model: This
model states that the universe undergoes an infinite series of creations and
ends (Big Bangs and Big Crunches). Accordingly, the universe we live in could
be the first of a possible series of universes or the nth universe
in the series.
DEATH
OF THE UNIVERSE
The end of the
universe probably won’t happen for at least the next 200 billion years. Let’s
look at some theories associated with this.
The Big
Crunch Theory: This
theory states that at some point, the expansion of the universe will reverse
and the universe will decrease in size, potentially leading to the end of the
matter. This also suggests that it will lead to the creation of the universe
all over again from the collapsed matter.
The Big
Rip Theory:
According to this theory, the universe will continue to expand till it is at
its maximum point of expansion. At this point, all the stars, planets and even
the tiniest of atoms will be torn apart and collapse into themselves.
WHY IS
IT IMPORTANT TO KNOW HOW THE UNIVERSE WAS CREATED?
The creation of the
universe out of absolutely nothing seems to defy all the laws of physics that
we know today. By investigating the centre of the universe, we might find the
mysterious fifth force of nature that will fill so many gaps in physics today,
including parts of Einstein’s Theory of Relativity. It will completely change
our understanding of the universe.
FUN
FACTS:
· * In 1992, instruments aboard the Cosmic Background
Explorer satellite showed that 99.97% of the energy of the universe was
released within the first year of its origin.
· * Astronomers theorise that 96% of the matter in the
universe is invisible or dark matter composed of matter that is difficult to
detect. The other 4% is made up of stars, planets and galaxies that can be
detected.
· * In 1998, two teams of astronomers announced that not
only is the universe expanding, but it is accelerating as well. According to
the researchers, the farther a galaxy is from Earth, the faster it is moving
away.
· * Three scientists --- Saul Perlmutter of Lawrence
Berkeley National Laboratory and University of California, Berkeley, USA; Brian
Schmidt of Australian National University; and Adam Reiss of Johns Hopkins
University and Space Telescope Science
Institute, USA --- won the 2011 Nobel Prize in Physics for the discovery
that the expansion of the universe is accelerating.
· * The first stars probably began to form out of hydrogen
when the universe was about 100 million years old. This is how our sun
originated close to 4.5 billion years ago.
