The ancient Indian Hindu texts describe units of time ranging from microseconds to trillions of years. According to these ancient Indian texts, the creation and destruction of the Universe is an ongoing cyclic process that repeats forever infinitely.
Universe as an endless cycle of creation and destruction
In other words, Universes are created and destroyed, and the process goes on and on. The process of creation (called Srishti in Sanskrit) of the Universe is personified in the form of Brahma – the God of Creation. The process of destruction (called PraLaya in Sanskrit) of the Universe is personified in the form of Shiva – the God of destruction. The permanance, the cycle of creation and destruction that goes on forever infinitely and hence is timeless and eternal, is personified in the form of Vishnu – the preserver who is permanent and all pervasive.
So, Brahma, Vishnu and Shiva form the trinity of Creation, Maintenance and Destruction. Hence they are called Trimurti – the three forms of the Universe. So God here is personified into the three forms – Generator, Observer, Destroyer – GOD
Instances of Universe in an endless Multiverse
So Universe in ancient Indian texts is not one single entity. But there are an infinite number of Universes that are continuously created and destroyed. In other words, we live in an Universe that belongs to a Multiverse. Our Universe will ultimately die, but the multiverse lives on. Vishnu is a personification of this multiverse.
Then we have the units of measurements of time, called Kaala Vyavahara. Many of these smaller units are the ones which an individual can experience in his life time – like second, minute, month, year, etc.
And there are other units of time that are beyond the age limit of an individual, and can be experienced only across thousands of generations, only by entire civilizations – like the Yuga.
And finally there are time units that can be experienced only at the level of the life time of entire Universes – like the Kalpa.
Units of Time in ancient Indian texts
The smallest unit of time in ancient Hindu texts is called Truti whose value is 0.031 microseconds! This is the base unit upon which other units are built. According to some other texts which use an alternate system of time measurements, a Truti is 35.5 microseconds.
If you need a modern analogy, think about how some part of the world prefers miles and some part of the world kilometers. This is similar, except that the name remains the same – Truti. In the vedic texts, the smallest unit of time used is Paramanu, which is 26.3 microseconds.
So even in ancient India we had different set of units of measurement, similar to how we have SI, CGS, FPS systems today. Each of these systems have other smaller units of time like Kshana (1.28 seconds), Laghu (1.6 minutes), Danda (24 minutes) etc.
But all these units of time in ancient Hindu texts converge to the same measurement at the level of a Muhurta which is 48 minutes of modern times. So, a Muhurta has a value of 48 minutes in all ancient Indian units of time.
So 30 muhurtas constitute an entire day (called ahoratri). While we have 24 hours in a day today, the ancient Indians had muhurtas instead of hours, and each muhurta lasted for 48 minutes of our times.
Also note that in ancient India, the day started with sunrise, unlike the midnight system we have today.
Yuga – large units of time
Yuga is a unit of time on the scale of thousands to millions of years. The ancient Hindu text Vishnu Purana has details about these Yuga measurements.
A Maha Yuga (great yuga) is made up of four sub yugas that are distributed in the ratio of 4:3:2:1
The smallest yuga in a mahayuga is a Kali Yuga whose measurement is 432,000 solar years. Next comes Dvapara Yuga which is 432,000 x 2 = 864,000 years. Then comes Treta Yuga which is 432,000 x 3 = 1,296,000 and finally we have the largest i.e the Satya Yuga which is 432,000 x 4 = 1,728,000 years.
So in all, a Mahayuga is a period of 4.32 million years on Earth.
Manvantara – Rise and fall of life forms
The next large unit of time after a MahaYuga in ancient Indian texts is called Manvantara. It is said at the beginning of a Manvantara, new life forms are created and at the end of it, those life forms are destroyed.
1 Manvantara is said to be of a duration of 71 Mahayugas, which makes it 4.32 x 71 million years which is 306.72 million years. So according to these texts, once the evolution of life starts on Earth, all life forms will be destroyed after a period of around 300 million years.
Interestingly, the Earth’s largest mass extinction event known to us, the Permian–Triassic extinction event is estimated to have occurred around 252 million years ago!! It is said that during this period nearly 90% to 96% of all species on Earth then were killed. This was also the only mass extinction period of insects on Earth!!
After each Manvantara i.e mass extinction of life forms, it is said that there exists a Sandhi Kaala, a boundary period, when the life on Earth is still undergoing recovery and is said to last for the period of 1 Satya Yuga (1.728 million years). According to the estimates of modern science, it is estimated that the recovery of life on Earth after the Permian–Triassic extinction event took around 10 million years. See, It took Earth ten million years to recover from greatest mass extinction
Kalpa – day of the Universe
Just like we humans have a day on Earth, Kalpa is defined as the day of the entire Universe itself! The time period for one Kalpa is said to be equivalent to 14 Manvantaras and their Sandhi Kaala. Also, it is said that there is one Sandhi Kaala before the first Manvantara of a Kalpa during which no life has evolved yet. So in all we have 14 Manvantaras and 15 Sandhi Kaalas in a Kalpa.
So, 1 Kalpa = 14 x 306.72 million years + 15 x 1.728 million years
which makes it 1 Kalpa = 4.32 billion years.
So 1 day at the Universal scale is said to be 4.32 billion years. It is said that the process of creation of life exists during this entire day and there is an equivalent universal night period during which no creation process takes place, which is another 4.32 billion years.
In other words, a complete day on the Universal scale is 8.64 billion years!
It is interesting to note that, according to modern scientific discoveries the oldest life form found on Earth is 4.28 billion years old! So according to the Kalpa calculation, life on Earth will continue to exist for another 400 million years!
Mahakalpa – The lifespan of a Universe
Kalpa – a day at Universal scale is further extended with days and years similar on earth so that a month at the Universal scale is 30 Kalpas i.e 30 Universal days. And a year at the universal scale is 12 such Universal months.
100 such years at the Universal scale are defined as the life span of the Universe, which means a Universe is said to end at the end of its 100 years of age. This is called a Maha Kalpa.
So the life span of an entire Universe is 8.64 x 30 x 12 x 100 billion years, which comes to around 311 trillion years!!
Shvetavaraha kalpa – the present day of the Universe
Finally, the ancient Indian texts say that our Universe is currently in the first day of its 51st year. And in this day of the Universal scale, we are in the Kaliyuga of the 28th Mahayuga of the 7th Manvantara.
The name of the Universal day is Svetha Varaha Kalpa. The name of the Manvantara is Vaivasvata Manvantara.
Age of the Universe as per ancient Hindu texts
So, getting back to our calculations again, the age of the Universe according to ancient Indian texts is
50 Universal years + 6 Manvantaras + 7 Sandhi kaala + 28 Mahayuga
50 Universal Years = 8.64 x 30 x 12 x 50 billion years = 155, 520 billion years
6 Manvantaras = 6 x 306.72 million years = 1,840.32 million years
7 Sandhi Kaala = 7 x 1.728 million years = 12.096 million years
28 Mahayuga = 28 x 4.32 million years = 120.96 million years
So the age of the Universe as per ancient Hindu texts is 157.49 trillion years!
Age of the Universe according to modern science
According to modern science, the age of the Universe is around 13.799 billion years. This is no where what the ancient Indian texts predict.
While modern science calculations are based on rigorously tested theories and data obtained from rigorous and painful observations, we have no empirical data or theory available in the ancient Indian texts about how the numbers were arrived at.
So this article is definitely not to say that the age of the Universe is 157.49 trillion years. Our conclusions should always be based on empirical data and solid theories, the scientific laws that are constantly questioned, refined and updated based on new evidence.
This article is only an attempt to appreciate the great scale of time on which ancient Indians were working on, irrespective of whether they were correct or wrong, because these time scales correspond to those in modern science. We do not come across any other ancient civilizations that talk in terms of billions or trillions of years, with specific names given to such large periods of time.
Like the famous American cosmologist Carl Sagan said in his book Cosmos,