Light and Life
Light is a form of energy that helps us see the world around us. Most living organisms need light to see. Man has always been captivated by light. He always remains inquisitive to know what it is made of as well as how and when it was formed.
It is now universally accepted that our Universe originated from a ‘Big Bang’. The Big Bang occurred when a single point in the cosmos either exploded or expanded. It released huge amount of energy at extremely high temperature and pressure. The energy that was emitted out was in the form of light particles. Each particle travelled in all directions at tremendous speed because of the high energy that each particle carried.
As the explosion cooled down, energy started being converted into subatomic particles like electrons, protons and neutrons. These particles gave birth to simple atoms like hydrogen, helium and lithium. In the meantime, the cooling of particles continued and bigger atoms came into existence. Energy was converted to matter. When matter was born, gravity started playing its role. Later matter started coming together to form stars and planets.
The Universe as we know today started taking shape. Millions of years ago, simple molecules like nitrogen oxide, carbon monoxide and water were formed. This was followed by the formation of bigger molecules like amino acids, sugars, proteins, carbohydrates and DNA. The process of evolution of life began. The various stages in evolution, from empty space to particles to simple atoms and molecules, cells and large, multicellular organisms have their origin in light. In short, life comes into existence from light.
Today, we know that light is electromagnetic radiation. It consists waves of electric and magnetic fields. Light has an unbelievable speed of 300,000,000 metres per second in vacuum. Nothing in the Universe can move faster than light. Though light is said to travel in the form of waves, the Big Bang Theory tells us that light is made up of particles.
Light is seen in the form of waves as well as particles. We understand the world around us through our eyes with the help of light. We use certain instruments that use light as the investigation when our unaided eyes are not enough. Thus, the life that arose from light is perceived and understood through light.