Like the crest on the peacock’s head,
Like the gem in the cobra’s hood,So stands mathematics
at the head of all the sciences.
-
Vedanga Jyotisa (Sanskrit text , 4th
century BC)
I will begin my article series on the ancient Indian
excellence with their knowledge in mathematics.
No work on mathematics can begin without talking about
Aryabhatta and his contributions.
Now without much hush bush , who is this Aryabhatta?
Aryabhata was a great
indain mathematician who was born around 476CE. He is the author of many great
works in the field of maths and astronomy. Lets have a look into few of his
excellent contributions. But before we can understand his contribution , we
need to understand aryabhatiya number system.
What is Aryabhatiya number system?
Ariyabhatiya number system is the system of numerals based
on the Sanskrit phonemes.
It was introduced by Aryabhata in the first chapter called
“Gitika Padam” in his classic work “Aryabhtiya”.
Āryabhaṭa’s code is a mapping of numbers to words that
employs first a division of the Sanskrit alphabet into two groups of consonants
and vowels .
The first 25 consonants called the varga letters of the Sanskrit alphabet are:
k=1 kh=2 g=3 gh=4 ṅ
=5 c=6 ch=7 j=8 jh=9 ñ=10 ṭ=11 ṭh=12 ḍ=13 ḍh=14 ṇ=15 t=16 th=17 d=18 dh=19 n=20
p=21 ph=22 b=23 bh=24 m=25
The remaining 8 consonants are the avarga letters: y=30 r=40 l=50 v=60 ś=70 ṣ =80 s=90
h=100 The varga letters (k through m), V, stand for squares such as 1, 100,
10000, and so on.
The avarga letters (y through h), A, stand for non-squares,
such as 10, 1000, and so on. The
following vowels are the place holders as shown: a=1 i=102 u=104
ṛ =106 ḷ =108 e=1010 ai=1012 o=1014
au=1016
So, ka to ma 1 to 25 Number, and ya is 30, ra is 40, la is
50 and upto sha 80. So, ka is 1, if you are putting ikaaram, ki x 100, if you
are putting ukaaram, ku x 10000, if you are putting rikaaram, kr x 1000000
Aryabhata used this number system for representing both
small and large numbers in his mathematical and astronomical calculations. This
system can even be used to represent fractions and mixed fractions.
For example
nga is 1/5, nja is 1/10 and Jhardam (jha=9; its half) = 4½.
Lets break it down. According to Aryabhata's number system explained above , "Na" gets the value 10 and if any consonant is added to by "Ikara" i.e "EE" it gets multiplied by 100. so Nee (NA+EE) becomes (10*100=1000) 1000 and "La" has the value 50. so the diameter of earth has become 1050 Yojanas.
Now lets breakup what is One Yojana.
One Yojana is said to be "Sachangulo Gahasthonara shi yojana", sa is 90, cha is 6, sachangulo is
96 angulam, one angula is average diameter of your finger, middle finger, 1.6
cm approx. x 96, i.e. your average height or gahastha tha 1, kha 2, ga 3, tha 4
gahastha from this tip to this tip x 4, that is your average height. Like that,
nara shi yojana, sha 80, shi 8000. So 8000 the average height of man is one
yojana is equal to 12.11 kms.
So how do you translate this in terms of the diameter of earth?
When he says "Neela Bhuvyasa" i.e the diameter of earth is 1050 Yojanas , it means the diameter of earth is 1050 * 12.11Kms approx = 12715.5Kms
Now what does the modern value say about the diameter of earth ?
A picture speaks 1000 words. So below is the snapshot from my best friend Mr.Google on the diameter of Earth.
Now how close is the modern value to the one perdicted by Aryabhatta ? Approximately 27Kms less .
I enjoyed writing this article as much as you enjoyed reading this.
Look forward to my next article to know more on what Aryabhata says on the rotation of Earth.
Look forward to my next article to know more on what Aryabhata says on the rotation of Earth.