Nasadiya Sukta- The Big Bang Theory in Rig Veda
The day we disregard our ancient knowledge is the day we start decaying. What differentiates a human being from any other living form is the knowledge that our ancestors preserved for us, accompanied with our instinct to learn and expand that knowledge. The four Vedas are one such example of widely disregarded (but precious) knowledge in modern world.
Through this blog post, I'll try to present one hymn from Rig Veda: The Nasadiya Sukta, that corresponds with the modern day Big Bang Theory. The Big Bang Theory is the theory of creation of universe. This theory explains how our universe started expanding from a Singularity after a big bang, and how it is still expanding.
Nasadiya Sukta is the 129th hymn of 10th Mandala of Rigveda (Rigveda - 10:129). Nasadiya literally means Not the non-existent. So Nasadiya Sukta translates to The hymn of Not the non-existent. The sukta (hymn) describes the creation of universe and the world as we see today. This post is intended to logically relate the seven verses of the hymn with the Modern Big Bang theory. Here we go!
Verse - 1 of Nasadiya Sukta 
Verse -1: The verse 1 of Nasadiya Sukta describes what existed (or not existed) before the creation of universe. There was no sky, no air, and no water. But there was (or wasn't) something. No one can tell what it was, where it was, and what covered it. In classical Big Bang Theory, this state is described as the State of Singularity. No one knows what a Singularity is, they are "thought to" exist as zones of infinite densities at the core of Black holes. All we actually know is that we are not sure what existed, or not existed before the Big Bang - described in the hymn as "THEN was not non-existent nor existent"
Verse - 2 of Nasadiya Sukta 
Verse - 2: The Verse 2 further describes the nature of what Modern Big Bang Theory calls Singularity. As per Big Bang Theory, our universe is "thought to" have begun from a Singularity: an infinitesimally small, vibrant, self-sustaining, and intensely dense singularity. There is no theory about its origination, where did it come from, how it got created and how it looked like.
The only thing that we know is "that One thing, breathless, breathed by its own nature: apart from it was nothing whatsoever."
Verse - 3 of Nasadiya Sukta 
Verse - 3: The third verse describes the nature of the Singularity, and
what lied inside it. The Big Bang theory "assumes" Singularity existed at the core of black holes amidst eternal darkness: an area of extreme gravitational pressure which compresses the finite matter into infinitesimally small directionless particles of infinite density which are extremely hot. All we know (or can assume) is that it was void and formless, and by the great power of warmth was born that Unit.
Verse - 4 of Nasadiya Sukta
Verse - 4: The fourth verse describes the triggering of Big Bang, the perpetual expansion that got triggered by a Desire: the primal seed and germ of Spirit. According to Space.com, a point came when this calm Singularity underwent an extremely brief and dramatic period of inflation, expanding faster than the speed of light. It doubled in size perhaps 100 times or more, all within the span of a few tiny fractions of a second. The Desire had risen. What is existent today started to develop from the non-existent.
Verse - 5 of Nasadiya Sukta 
Verse - 5: The fifth verse describes what happened moments after the Big Bang. The expansion of the universe started, and it had no specific direction. There were mighty forces, free action and endless energy generated from the phenomenon.
On similar lines, The Big Bang Theory states that immediately after the Big Bang, there was a chaos (free action) in a 10-billion degree sea of Neutrons, Protons, Electrons, Positrons, Photons, and Neutrinos. The expansion started, and so was the gradual cooling of the universe. Ref. NASA 
Verse - 6 of Nasadiya Sukta 
Verse - 6: The sixth verse describes what the scientists know today: No one can conclusively prove anything about the Big Bang. Einstein's Theory of Relativity talks about the idea of Singularity, however, the current researchers such as Sean Carroll from Caltech denies this theory on the grounds of Quantum Mechanics. According to Space.com, " the very beginning of the universe remains pretty murky "
Verse - 7 of Nasadiya Sukta 
Verse - 7: This self explanatory verse concludes the Nasadiya Sukta with the statement that none in the world, even the first born of this creation, knows about this creation of Universe. It's hard to comprehend by the human mind, and impossible to be proved conclusively by any living being.
Rig Veda is one among the four Vedas, the ancient sacred (and scientific) texts of Hinduism. It is a collection of 1028 Hymns (Suktas) and approximately 10,600 verses.
The author of this post, Rishi, is an IIM Calcutta alumnus and author of India's first Mythological Science - Fiction book series The Whispering Dwapara.
3. Rig Veda, tr. by Ralph T.H. Griffith, , at sacred-texts.com. https://www.sacred-texts.com/hin/rigveda/rvi10.htm