It is the regular opinion especially among many astronomers and scientists that the universe began about 14 billion years ago. They think it suddenly exploded into being on its own. They call this beginning the big bang.
According to them, all space and time began with the big bang. Some astronomers still claim that with a special and sophisticated telescope, they can see radiation left over from the big bang. They call this cosmic background radiation.
The big bang theory holds that the universe was hotter beyond any human imagination at the moment it began. As a result, it started to fly outward, or expand, as it expands it started to cool, tiny particles that would make up matter started to form, all of these happened in just a few minutes.
When the universe was about one million years old says the scientist, it had cooled to about 5900 Fahrenheit (3300 Celsius). This temperature, they said was still scorching but it was cool enough that tiny bits of matter called atoms started to form. All the tiny objects around us – the cars, the telephones, the computers, the floor, the air etc, are made of atoms. The atoms gave off rays of light.
It is believed that the force of gravity pulled gas and dust together for over millions of years. Stars and galaxies formed from clumps of gas and dust. The stars began to shine, the sun and the solar system are said to have formed about 4.6 billion years ago.
There are so many theories propounded by astronomers towards explaining the origin of the universe, however, the big bang theory seems to have dominated all other theories except the religious/creationist account of the origin of the universe which is mostly held by all the religions of the world.
The Big Bang Theory
The big bang theory of the origin of the universe has received wide attention and acceptance in different quarters. The big bang theory proposes that the universe was once extremely compact, dense and hot. Some original event, a cosmic explosion called the big bang occurred about 13.7 billion years ago and the universe has since been expanding and cooling.
The big bang theory seeks to explain what happened at or soon after the beginning of the universe. According to the big bang theory, the universe expanded rapidly in its first microseconds. A single force existed at the beginning of the universe and as the universe expanded and cooled, this force separated into those we know today: gravity, electromagnetism, the strong nuclear force and the weak nuclear force.
Some philosophical questions that can be raised against this theory are these: what was the origin of the explosion – that is, what actually created the elements that made the explosion possible? Again, who was actually there when this explosion happened to determine that every other thing in the universe took shape immediately following the explosion? Thus, because scientist cannot look back in time beyond that early epoch, the actual big bang is hidden from them. There is no way at present to detect the origin of the universe.
Further, the big bang theory does not explain what existed before the big bang. Hence, due to its inability to explain beyond every doubt and to convince the intelligent and spiritual mind that the universe actually originated from the hot explosion, the big bang theory can only be accepted for what it is – a theory, and not a fact that can be logically relied upon.
The Religious/Creationist theory
This theory is based on the creation account given in the book of Genesis in the Christian Bible. According to this account, man was created by God in his own image and likeness and was placed on earth to multiply, to be fruitful and to subdue the earth.
The creation theory tries to present the fact that man was purposefully created and did not evolve by chance. God the omnipotent and omniscience had thought of man and after creating every other thing, created man to be the master of all things.
In that way, man was accorded not only a human status but also a spiritual status, distinguishing him from all other creatures. The creation theory is supported and accepted by all the religious denominations not as a scientific fact but as a dogma based on the unquestionable words of the Bible.
The Scientific/Evolution Theory
The scientific or evolution theory of the origin of man differs radically from the creationist theory because most of the adherents of this scientific theory were professed atheists. According to the scientific or evolution theory, about 3.5 billion years ago, conditions developed in which it was possible for life to emerge.
The world ocean and atmosphere, affected by the proliferation and evolution of early life–forms, underwent major transformations, many of which would later enable the evolution of higher life forms.
Since then, according to this account, life has evolved from single cell organism into microorganism, insects, plants and animals we know today. The world atmosphere has evolved as well, both influencing and influenced by the life forms living within it.
The evolutionist theory states that:
- All life forms (species) have developed from other species.
- All living things are related to one another to varying degree through common descent. In other words, they all share common ancestors.
- All life on earth has common origin. That in the past, there once existed an original life form and that this life forms gave rise to all subsequent life forms.
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