Subject: Re: [HM] Indian astronomy and mathematics
From: Dinesh Maheshwari (dsm@cypress.com)
Date: Wed Feb 09 2000 - 00:09:56 EST
Kim Plofker (KP) wrote:
> "More recent" is not always the same as "better informed"; I like
> Thurston's book (a general survey of premodern astronomy in world
> cultures) very much and find much useful information in it, but
> Shukla and Sarma know more about Indian astronomy than Thurston does.
While it is one's prerogative to denounce, even for no reason at all,
H Thurston's understanding of Indian astronomy to be wrong, one
cannot deny Thurston a claim of extensive erudition of ancient world
astronomy. He claims the "glimmerings" of the heliocentric model for
Aryabhata's system but not for the Babylonian system.
> We've already gone through these points and discussed which of them
> are supported by textual sources from what's known of Aryabhata's work
> and which are not. A reference to MacTutor that provides no verifiable
> citations of primary textual sources will not further the discussion
> much, I'm afraid.
Well, MacTutor does indeed list 30 books and articles as references
and in the very top section you find "Shukla, Kripa Shankar Glimpses
from the 'Aryabhata-siddhanta', Indian J. Hist. Sci. 12 (2) (1977),
181-186."; the same author who co-authored "Aryabhatiya", [New Delhi
1976] that KP has referred to, in her posts.
For MacTutor's write-up on Aryabhata, please refer to
http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Aryabhata.html
The references are available through the hypertext link towards the bottom
of the article. You can also go directly to the references using the link
below.
http://www-groups.dcs.st-and.ac.uk/~history/References/Aryabhata.html
> The Sanskrit texts we see quite definitely assign to all seven planets,
> including the sun, orbital periods and orbital distances with respect to
> the earth.
As I had mentioned in the previous post, there appear to be two systems.
One for measurement and primary observation (heliocentric) and another
for rendering time and position of the heavenly bodies with respect to the
earth, earth being the vantage point of the observers(geocentric) with
mapping done from the former to the latter. The "Sanskrit
texts" that KP refers to can very well be descriptions of the second system
and do not imply (and neither can be used to infer ) the absence of the
first system. In fact, one would expect references to only the more
practical second system in a compilation of the formulas.
> If we assume that the existence of the sighra-correction
> implies a truly heliocentric cosmology, we will have to assume that
> almost all ancient astronomy had a heliocentric system too: for example,
> Babylonian astronomy was based on synodic planetary periods, which also
> computationally link the position of the planet to that of the sun.
First, as I understand sighrocca, it is a mapping of the motion of the
planets around the sun to an imaginary point moving around the earth.
Second, equating the concept of sighrocca to synodic planetary periods
in significance is tantamount to seriously (perhaps purposefully)
undermining the significance of the concept of sighrocca; synodic
planetary periods is a very primitive concept compared with sighrocca.
> Recall, after all, that Brahmagupta and many later authors,
> who all used the sighra-correction as a matter of course, strongly
> rejected Aryabhata's notion that the earth might even rotate;
I am not surprised to see Brahmagupta disagreeing with Aryabhata,
the two schools of astronomy (from two different geographical
locations in India) were rivals and were competing with each other.
For instance, Brahmagupta also calculated the length of the year which
disagreed with that of Aryabhata. However, it has to be said that
Brahmagupta's school was quite influential in western and northern
India during his time.
> this was considered impossible for many of the same intuitive
> physical reasons that European anti-Copernicans put forth. I don't
> feel that we're justified in inferring that these siddhanta authors
> accepted the hypothesis of the earth's hurling through space, when
> a simpler interpretation (i.e., sun-dependent models need not be
> literally sun-centered) will cover the facts.
Perhaps, there is a preconceived notion that the ideas of "time and
space" in ancient India were the same as in contemporary Europe.
Let me quote from Yoga-Vasishta(YV) composed by Valmiki,
author of the epic Ramayana. YV is a book of philosophy and describes
instructions given to Rama, the hero of the epic Ramayana.
Consider the following quotes from YV [translated by Venkatesananda, S.
in "The concise Yoga Vasistha" 1984, Albany (State University of New
York) Press.]
1. "The world is like a potter's wheel: the wheel looks as if it stands
still, though it revolves at a terrific speed"
2. "There are three types of space - the psychological space, the
physical space and the infinite space of consciousness. The infinite
space of undivided consciousness is that which exists in all, inside
and outsite .. The finite space of divided consciousness is that which
created divisions of time, which pervades all beings ... The physical
space is that in which the elements exist. The latter two are not
independent of the first."
3. "Just as space does not have a fixed span, time does not have a fixed
span either"
4. "(There are) countless universe, diverse in composition and space-time
structure... In every one of them there are continents and mountains,
villages and cities inhabited by people who have their own time-space and
life-span."
5. "The entire universe is forever the same as the consciousness that dwells
in every atom" - refers to non-duality of the laws of universe and the atom.
Yes, there was a notion of atom ("pramanu") [expounded fully by Kanada in
6th century BC in his philosophy of Vaisaikha] and all matter was considered
to be composed of combinations of the 5 basic atoms.
As I mentioned in the previous post, there are hints of an idea of a
heliocentric system in _Satapatha_Brahamana_(SB)[. Consider SB 8.7.3.10
which says -
"The sun strings these worlds - the earth, the planets, the atmosphere-
to himself on a thread. This thread is the same as the wind"
The atmosphere here refers to the "ether" and the "wind" refers to
the "cosmic wind" which was supposed to hold the system together.
In Vedic cosmology, earth is part of a universe that undergoes deaths and
rebirths in cycles. Dr. Carl Sagan, (1934-1996) , astro-physicist, in his
book "Cosmos" says:
"The Hindu religion is the only one of the world's great faiths dedicated
to the idea that the Cosmos itself undergoes an immense, indeed an infinite,
number of deaths and rebirths. It is the only religion in which the time
scales correspond, to those of modern scientific cosmology. Its cycles run
from our ordinary day and night to a day and night of Brahma, 8.64 billion
years long. Longer than the age of the Earth or the Sun and about half the
time since the Big Bang. And there are much longer time scales still."
The above citations should give you an idea that the Vedic people did not
consider the earth to be the central element of importance in the spatial
or temporal reference of the universe.
Best regards,
Dinesh
PS 1: A number of the modern western quantum physicists were familiar with
the Vedic texts and it seems were particularly interested in the notions of
non-duality of time and space, matter and consciousness etc.
The list includes : Albert Einstein, J R Oppenheimer, Fritjof Capra, Erwin
Schroedinger, John Dobson, David Bohm, etc. Werner Karl Heisenberg seems to
be familiar with the Vedic texts but may not have done extensive reading
himself. I can provide quotations from the above physicists, if any one is
interested.
PS 2:
A.L. Basham, Australian historian :
"Ancient Indian theories lacked an empirical base,
but they were brilliant imagnative explanations
of the physical structure of the world, and in a large measure,
agreed with the discoveries of modern physics. "
Grant Duff -British Historian :
"Many of the advances in the sciences
that we consider today to have been made in Europe
were in fact made in India centuries ago."
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