As regards the concept of time, the calculation was done on the basis of Padardha (Matter) and Parithi (Space); the sum of Space occupied and the movement of Matter determined is the Paramaanu Samaya (atomic time). Thus the Matter, Space and Time are measurable. The Time Units were arrived as per the mix of these Entities called Traserenus or celestial atoms and the duration of integrating these entities. The smallest unit of three traserenus is called ‘triti’; hundred tritis make one vedha; three vedhas  make a lava; three lavas make one nimesha or blink of an eye; three nimeshas one kshana; five nimeshas one kashta or eight seconds; fifteen kashtas one laghu or two minutes; fifteen laghus one nadika or danda; six-seven dandas one fourth of a day or night; four praharas or yamas make one day and night; two pakshas a month; two months a Ritu /season; six months one Ayanam or two complete movements of a year by Sun; Dakshinayana is the movement of Surya from top to bottom and Uttarayana is the movement of Sun from bottom to top. 365 combinations of a day and night make a year. Normally the span of human life is hundred years. A human year is a day to Devas; Satya Yuga is stated to have a span of 4800 Deva Years; Treta Yuga 3600 Divine years;Dwapara Yuga 2400 years; Kali Yuga 1200 years; 12000 divine years one Maha Yuga; 1000 Maha Yugas make one Kalpa or a day to Brahma and two Kalpas one day and night to Brahma; Brahma’s life span is 100 Brahma Years or two Pararthas; one Maha Kalpa is half of Brahma’s life span; Brahma’s present age is now fifty years plus;that is how our  daily prayer states: Dwiteeya Parthaey! One Maha Kalpa there are a mind-boggling 311040 crore of human years. We are now in the 28th Kaliyuga of the First Day of the First Year of Sweta Varaha Kalpa, second Parartha in the reign of the Seventh Manu Vaivaswata. Kali Yuga is calculated to have commenced on 17th February 3102 BC of Julion Calendar. Each Manu rules for 71 Maha yugas. Brahma is 51 year old having lived for 155 trillion years. We are now in the Third Kalpa (Varaha Kalpa).