The system of time division of the ancient Hindus features a profoundly interesting pattern: Mathematically, it builds up from Man to God (see Beethoven and the God-Conception), and experientially, it builds up according to the time dilation and expansion we have, at some time or the other, experienced.
From Wikipedia: One tithi (lunar day) is the time it takes for the longitudinal angle between the moon and the Sun to increase by 12 degrees. Tithis vary in duration from approximately 19 to approximately 26 hours.
One paksa (lunar fortnight) consists of 15 tithis.
One Maasa (lunar month) is twice the above.
One Hritu (season) lasts 2 Maasa
Three Hritus make one Ayana, two of which make a human year.
This is one day of the gods (the devas).
4,800 divine years equalling 1,728,000 human years equal one Satyug (one grand era of perfect peace).
3,600 divine years, equalling 1,296,000 human years is one Tretah Yuga (one grand era of relative equanimity).
2,400 divine years, equalling 864,000 human years is one Dvaapara Yuga, which is one grand era of degenerated lawfulness.
1,200 divine years, which is 432,000 human years, equals one Kali Yuga, an era of the present kind.
So, 12,000 divine years, summing the four Yugas, equals 4,320,000 human years; this is called one Mahaa-Yuga.
A thousand Mahaa-Yugas equal a Kalpa, which is one day (only the day; not the night) of Brahma, the Creator.
From the Music we have heard, we may devise a similar, albeit not perfectly accurate, system of time:
One Music-Microcosm is the time it takes for the Mind’s eye to broaden by 12 degrees. Music-Elements vary in duration from 19 to 26 minutes; 60 Music-Microcosms, by repetition, comprise a Music-Element.
One Theme (or Variation), for us a fortnight’s worth of truth and music, consists of 15 Music-Elements.
One Theme & Variation pair (for us, a month’s worth of truth and music) is twice the above.
One Movement lasts 2 Themes.
Three Movements make one Master-composition, two of which make a human year. This is one day of the Gods (any of the four Masters).
4,800 Mozart-years (equalling 1,728,000 human years) equal a grand era of perfect peace.
3,600 Schubert-years, equalling 1,296,000 human years equal one grand era of sad equanimity.
2,400 Brahms-years, equalling 864,000 human years, is one grand era of cunning victory, which also encompasses sentimentality.
1,200 divine years, which is 432,000 human years, equals one Beethoven-Era, an era we have as our Legacy.
So, 12,000 divine years, summing the Grand Years of the Four Masters, equals 4,320,000 human years; this is called one Mastermusic-Aeon.
In contrast with the system of the ancient Hindus, in the Music of the kind we have heard, time lies condensed within time: A thousand Mastermusic-Aeons equal one Supreme-Beethoven, the last movement of Opus 131, String Quartet Nr. 14 in C# minor. Ludwig van Beethoven’s Mastermovement, unheeding to – yet irrevocably part of – one Mastermusic-Aeon is contained within the Scheme of Time He Himself decides. With this, His Day is done (cf Wagner).