How many divisions of time in the Hindu Scriptures?
THE PURĀNIC DIVISIONS OF TIME
In Hinduism there are three main divisions of the time employed in the Hindu Scriptures are
- Yugas-Yuga in Hinduism is an era within a four age cycle.It's Starts with Krita Yuga further Treta Yuga then Dvapara Yuga afterall Kalyuga(current).
- Manvantaras-it is a Sanskrit word, a compound of manu and antara, manu-antara or manvantara, verbatim it mean the duration of a Manu, or his life length.
- Kalpas-a kalpa is the period of time between the creation and recreation of a world or universe. 1 kalpas=4.32 billion years.
Here is the source There are four Yugas, which together increase to 12,000 divine years.Their respective duration is as follows:—*
The Krita Yuga = 4,800 divine years.
The Tretā Yuga = 3,600 „ „
The Dvāpara Yuga = 2,400 „ „
The Kāli Yuga = 1,200 „ „
"The one day of god is equal to the one year of human beings." As 360 is taken as the number of days in the year—
The Krita Yuga = 4,800 x 360 = 1,728,000 years of mortals.
The Tretā, Yuga = 3,600 x 360 = 1,296,000 „ „
The Dvāpara Yuga = 2,400 x 360 = 864,000 „ „
The Kāli Yuga = 1,200 x 360 = 432,000 „ „
*One Mahāyuga, or Great Age, including the four lesser Yugas, therefore, being 12,000 divine years = 4,320,000 years of mortals. "A thousand such Mahāyugas are a day of Brahmā," and his nights are of equal duration; a Kalpa, therefore, or Day, of Brahmā extends over 4,320,000,000 ordinary years. "Within each Kalpa 14 Manus reign; a Manvantara, or period of a Manu, therefore, is consequently one-fourteenth part of a Kalpa, or day of Brahmā.**
"In the present Kalpa, six Manus, of whom Swyambhuva was the first, have already passed away; the present being Vaivasata. In each Manvantara (period of a Manu), seven Rishis, certain deities, an Indra and a Manu, and the kings, his sons, are created and perish. A thousand systems of the four Yugas occur coincidentally with these fourteen Manvantaras, and consequently about 71 systems of four Yugas elapse during each Manvantara, and measure the lives of the Manus and the deities of the period. At the close of this day of Brahmā, a collapse of the universe takes place, which lasts through a night of Brahmā, equal in duration to his day, during which period the worlds are converted into one great ocean, when the lotus-born god (Brahmā), expanded by his deglutition of the universe, and contemplated by the Yogis and gods in Janaloka, sleeps on the serpent Sesha. At the end of that night he awakes and creates anew.
"A year of Brahmā is composed of the proper number of such days and nights, and a hundred of such years constitute his whole life. The period of his life is called Para, and the half of it Parārddha, or the half of a Para. One Parārddha, or half of Brahmā's existence, has now expired, terminating with the great Kalpa called the Padma Kalpa. The now existing Kalpa, or day of Brahmā, called Varāha (or that of the boar), is the first of the second Parārddha of Brahmā's existence. The dissolution which occurs at the end of each Kalpa, or day of Brahmā, is called naimittika, incidental, occasional, or contingent." *
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Here is one more source :-
The Puranas describe a number of time cycles within cycles. Discussions of these cycles can become confusing because different cycles are measured in different types of units. For example, the cycles are often described in units of deva years ( years in the higher planets ), each of which equals 360 human years.
The following description starts with the smaller cycles and works up to the larger ones. The length of each cycle is given in ordinary human (earth) years, as well other units where appropriate. Large numbers are described using the conventions of American English: thus, a million is a thousand thousand, a billion is a thousand million, a trillion is a thousand billion.
In Hinduism, the division of time is based upon the movement of atom over space and starts from the smallest unit called paramanu to the larger ones called yuga, mahayuga, manvantara, etc. up to the largest one called Mahakalpa.
sa kālaḥ paramāṇur vai yo bhuṅkte paramāṇutām
sato ’viśeṣa-bhug yas tu sa kālaḥ paramo mahān [SB - 3.11.4]
Atomic time is measured according to its covering a particular atomic space. That time which covers the unmanifest aggregate of atoms is called the great time.
The 3.11 chapter of the Bhagavata contains a description of the smallest units of time which can be listed as below:
Paramāṇu - 26.3 µs
Aṇu - 57.7 µs
Trasareṇu - 158 µs
Truṭi - 474 µs
Vedha - 47.4 ms
Lava - 0.14 s
Nimeṣa - 0.43 s
Kṣaṇa - 1.28 s
Kāṣṭhā - 6.4 s
Laghu - 1.6 min
Danda - 24 min
Muhūrta - 48 min
Ahorātram (Day) - 24 h
Then there are masa(month), varsa(year / solar year), devavarsa (divine years), etc. which constitute yugas:
- Satya Yuga - (1,728,000 solar years)
- Treta Yuga - (1,296,000 solar years)
- Dvapara Yuga - (864,000 solar years)
- Kali Yuga - (432,000 solar years)
Then there are Mahayugas up to Mahakalpa :
- 12,000 divine years = 4 Yugas (= 4,320,000 human years) = 1 Mahā-Yuga
- 1008 Mahā-Yugas = 1 Kalpa = 1 day (day only) of Brahma
- 30 days of Brahma = 1 month of Brahma (259.2 billion human years)
- 12 months of Brahma = 1 year of Brahma (3.1104 trillion human years)
- 50 years of Brahma = 1 Parārdha
- 2 parardhas = 100 years of Brahma = 1 Para = 1 Mahā-Kalpa
The interesting point about the division of time in Hinduism is that it talks about relativity of time thousands of years ago. So we can only guess how spiritually advanced the sages are.