Origin of the Universe

The most popular theory of our universe’s origin states that the universe originated from the big
bang some 13.7 billion years ago. This theory was born of the observation that other galaxies
are moving away from our own at great speed, in all directions, as if they had all been propelled
by an ancient explosive force. In 1927, Edwin Hubble, an American astronomer, while studying
the galaxies using a powerful telescope discovered that the universe was expanding. The
farther away the galaxies are, the faster they recede from each other. The statement that there
is a direct correlation between the distance to a galaxy and its recessional velocity as
determined by the red shift is known as Hubble’s Law.

If the universe is expanding, then it means that if we move back in time the universe would get
smaller and smaller. If we moved back to 13.7 billion years ago, then everything in the universe
should be a single point in space. That point is extremely dense and bound by immense
gravitational force. Some yet unknown factor caused this to explode and expand, thus creating
this universe. This explanation is called the Big Bang Theory.