Big Bang Theory

The Big Bang Theory is a popular theory about how the Universe came into existence. This theory explains the origin of the Universe, which is believed to have begun with a resounding bang when there was nothing else. The matter and energy that were used to form the Universe had existed in a vacuum in a compact form. The entire Universe was concentrated in a minuscule space about the size of an atom.

What is the Big Bang Theory?

There was neither space nor time in the beginning. However, the Big Bang resulted in an expansion of the entities within that tiny area with matter, energy, time, and space being created. Soon enough, the matter came together to form the planetary bodies and stars. Huge clouds of gases were created according to the Big Bang Theory. Scientists believe that the Universe is still undergoing expansion. However, it is going to end in the future. The Universe will then start to collapse until the big crunch takes place. You would have to study the various theories associated with this expansion to get the idea behind this theory.

What was there before the Big Bang?

No one knows for sure! However, scientists, particularly cosmetologists, have studied the condition for years before volunteering theories about the expansion of the Universe and how it resulted in the formation of life on earth. The latest model, known as the “Inflationary Universe” model, describes the condition before the Big Bang happened. According to scientists, space was filled with tiny points of a highly concentrated form of energy that was extremely unstable. The Big Bang caused the energy to transform into matter. Thus, the Universe was formed. However, no one has many ideas about what was present in the vacuum before the gigantic explosion occurred.

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What caused the Big Bang?

Astrophysicists believe that a small point of concentrated energy burst forth in a huge explosion, causing a resounding sound that is termed the Big Bang. The resulting matter that was created spilt-out in all directions, forming stars, galaxies, and planets in its wake. The Milky Way or our galaxy is not the only one out there in space. On the contrary, the Big Bang Theory tells you that there are billions of galaxies in the Universe today. Some of them may even have been destroyed, with many new ones created years after the Big Bang Theory of the Universe occurred.

How does the Universe appear today?

The explosion resulted in a  light, with the photons getting scattered by the tiny electrons in the newly formed matter. The hot Universe began to cool slowly once most of the matter was used up. This caused the nuclei to unite with electrons, thus creating a neutral atom. This action was termed recombination. It made the Universe appear opaque, as the free electrons scattered the photons to distant locations. Eventually, all the free electrons recombined to create the neutral atoms that made the Universe appear transparent. The photons bathed the Universe with an afterglow that is seen today. Cosmologists term it as “Cosmic Background Radiation,” which was explained after the Big Bang Theory was used to describe the creation of the Universe.

Mystery of a rapidly expanding Universe

Scientists who described the explosion using the Big Bang Theory explained that the Universe would expand for a period and then gradually slow down. The decrease in the rate of expansion would be the result of the cooling of the Universe. The explanation was simple, with the astrophysicists describing the gradual process as follows:-

• Huge mass forms gravity
• Gravity exerts a pull on the body
• Expansion is thus slowed down

However, the reality turned out to be different. Scientists observing the supernovae found that the Universe was rapidly expanding  instead of slowing down. There was a strange force that was pushing the galaxies further away from each other. This force was termed dark energy. Its properties are yet to be discovered, but scientists are working on it to find a perfect explanation.

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Is there any proof of the Big Bang Theory?

Some early scientists have been able to provide a proof about the occurrence of the Big bang or a gigantic explanation that may have occurred 13.7 billion years earlier. They have found the following elements in the Universe and measured the quantities:

This proves that the increased amounts of lighter elements than the heavier ones could only have been found in a Universe that was hot and dense. Other calculations reveal that the Universe cooled gradually and began expanding, sending the lighter elements away from its core.

Some other pieces of evidence that establish the Big Bang Theory include the following:

• Expansion of galaxies- Studies by the renowned scientist, Edwin Hubble, in 1929 show that the galaxies outside the Milky Way are moving further away. The speed of this movement has been noted as being directly proportional to its distance from the Milky Way. The inference derived from this study stated that the Universe must have occupied a minuscule area resembling a point at the beginning of time. The explosion was what caused the Big Bang

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Cosmic background radiation– The photons scattered by the Big Bang can be viewed today as an afterglow known as cosmic background radiation.