Talk:History of gravitational theory

Al Biruni

   "If such were the case, stones would and trees would fall from the earth."
   —Al-Biruni (1030), Ta'rikh al-Hind (Indica)

I assume the quote is supposed to contain "stones would fly" or the like. 74.78.162.229 (talk) 00:50, 4 July 2008 (UTC)

New Theory of Ligh Gravity - TOLG- light pressure gravity from proton photon light

I (Col Parkes in Autralia) have proposed a new theory of gravity. It is based on the difference in light pressure due to mutual shadowing. The light is not conventional electron photon light (EP) but from proton photon light (PP). This has much higher energy and hence momentum and this creates sufficient pressure at subatomic level (proton/neutron)due to elestic collisions. The light is iso tropic or more like iso cosmic inward from all directions. The difference in pressure between two bodies is caused by a shadowing between them. The inverse square law is simply due to change in the area (solid angle) of the shadow due to distance. The main problem with TOLG is shielding but PP has high penetration and shielding is considered minor. TOLG acts at speed of light and this solves the Mercury orbit problem and others. However TOLG creates problems for the BIG BANG and assocaited cosmic outcomes from GR. Appreciate comments. Thanks, Col 144.134.23.110 (talk) 07:29, 13 November 2008 (UTC)

Islamic philosophers and gravity

I believe that the claims on this page about Islamic philosophers and gravity involve some misunderstanding (or over-interpretation) of the sources. Claims about there being a "force of attraction between heavenly bodies" probably originate from philosophical discussions about the nature of the celestial spheres. Aristotle believed that they were made of a fifth element, which had neither "gravity" nor "levity" (i.e., which did not naturally move towards or away from the centre of the universe). Some other philosophers debated whether these spheres might not instead be composed of the standard four elements, which would then cause them to have a natural movement towards the centre of the universe. It would then be God that kept them moving with an (unnatural) circular motion, rather this being due to their own nature.

If I can find some good sources on this, I'll try and update the information here.

All the best. –Syncategoremata (talk) 22:32, 24 April 2010 (UTC)

And I've just noticed that the claim that

In 1121, Al-Khazini, in The Book of the Balance of Wisdom, differentiated between force, mass, and weight

is a complete misrepresentation of the original source (Hill, Donald R. (1993). Islamic Science and Engineering. Edinburgh University Press. ISBN 978-0-7486-0455-5.) which actually says:

al-Khazini repeats the vagueness of the Greeks in failing to differentiate clearly between force, mass and weight. (p. 61)

So I've removed it from here and will do so from wherever else it has crept in Wikipedia.

All the best. –Syncategoremata (talk) 22:46, 24 April 2010 (UTC)

I think there were expresions clearly referring to gravity, and should not be neglected, such as this quote by Abu Rayhan Biruni

"The attraction of all things towards the center of the earth."

So, I don't think this was just a philosophy.--Email4mobile (talk) 23:40, 8 September 2010 (UTC)

In a word NO please see Rāshid, Rushdī; Morelon, Régis (1996). Encyclopedia of the history of Arabic science. Psychology Press. p. 622. ISBN 9780415124119. Retrieved 9 September 2010. "The phenomenon of variation of the gravity of bodies with variations of their distances from the center of the Earth was discovered only in the eighteenth century after a certain development in the theory of gravitation". Also the "Muslim Heritage" site is not a wp:rs as per http://en.wikipedia.org/wiki/Wikipedia:Reliable_sources/Noticeboard/Archive_18#History_of_Science. Also see WP:Jagged 85 cleanup Thank you J8079s (talk) 17:54, 9 September 2010 (UTC)

Aryabhata's "heliocentrism"

I have removed the references to Aryabhata's supposedly heliocentric system from the article because every reliable source I have seen on the subject says unequivocally that it was geocentric. See Aryabhatta's "heliocentric" system on the Heliocentrism talk page and Abu Ma'shar al-Balkhi on the Geocentric model talk page for further details. As indicated in the second of those discussions, the mathematician and historian Bartel Leendert van der Waerden, who is apparently the source from which all such claims of heliocentrism have been derived, explicitly says, in the paper there cited, that Aryabhata's system was not heliocentric, but merely that it might have been "based on" a heliocentric system previously developed by Seleucus and possibly some of his followers. In that paper van der Waerden does not even make it clear whether he thought Aryabhata had derived his own system directly from a heliocentric one which he had access to, or whether he thought the traces of heliocentrism which it supposedly contained could have been inherited indirectly via transmission through other non-heliocentic descendents of Seleucus's.

Also, the source cited in the article, Alberuni's India. An account of the religion, philosophy, literature, geography, chronology, astronomy, customs, laws and astrology of India about A.D. 1030, says on page 266:

"... according to them [i.e. Hindu astronomers] the earth is in the centre of the universe, and everything heavy gravitates towards it."

and it is clear from the subsequent pages that both Brahmagupta and Aryabhata are among the "Hindu astronomers" which Al-Biruni was referring to in this passage.
David Wilson (talk · cont) 07:04, 10 May 2010 (UTC)

Quotation from De revolutionibus orbium coelestium

A recent edit has asked for a translation of the fragment of text "...inter centrum gravitatis terrae, & centrum magnitudis..." quoted from Copernicus's De revolutionibus orbium coelestium. The fragment comes from Chapter 3 of Book I. A translation by Charles Glenn Wallis is indicated by the italicised text in the following passage taken from Volume 16 of Great Books of the Western World:

"It can be gathered that there is no difference between the centres of magnitude and of gravity of the Earth from the fact that the convexity of the land spreading out from the oceans does not swell continuously, ..."

Since I can't see how this has any relevance to the history of gravitational theory, I am simply going to remove it from the article.
David Wilson (talk · cont) 06:28, 28 July 2014 (UTC)

Bogus quotation of Bhaskaracharya

The supposed quotation of Bhaskaracharya added to the article by this recent edit is bogus. Also, since Bhaskaracharya lived in the 12th century, he cannot have been responsible for anything that appeared in the Surya Siddhanta in 400-500 AD.

In Chapter 3, paragraph 6 of his Siddhanta Shiromani Bhaskaracharya did write:

"The property of attraction is inherent in the Earth. By this property the Earth attracts any heavy unsupported thing towards it: The thing appears to be falling [but it is in a state of being drawn towards the Earth]."

But there's nothing here, or anywhere else in his writings about "the earth, planets, constellations, moon, and sun" being "held in orbit due to this force." In fact, in the very same work, Bhaskaracharya states unequivocally that the Earth remains stationary in the heavens and is encompassed by the orbits of the Moon, Sun, planets and stars, so he cannot have even believed that the Earth itself had any orbit to be held in.

A previous discussion of this issue has already been held on the talk page of the article Gravity.
David Wilson (talk · cont) 00:04, 11 February 2016 (UTC)

I have now removed the quotation from the article.
David Wilson (talk · cont) 00:17, 11 February 2016 (UTC)

Good job it is all done by the new wave of hindu nationalist who want to rewrite history by fake quotation. Obiwana (talk) 20:59, 12 December 2022 (UTC)

Note

It has been said by Gillispie that Galileo "admired" Kepler's ellipses. It will be interesting to see Gillispie's grounds for saying this. — Preceding unsigned comment added by 2A00:23C4:7C87:4F00:F5B7:3823:63E2:4414 (talk) 12:47, 25 July 2020 (UTC)

See page 51 of Gillispie's book, of 1960. — Preceding unsigned comment added by 2A00:23C4:7C87:4F00:F5B7:3823:63E2:4414 (talk) 12:50, 25 July 2020 (UTC)

Thanks for pointing this out. As far as I can tell, Gillispie was referring to Galileo's regard of Kepler's work in general. It seems that the communication between the two was mostly one-sided from Kepler. Galileo regarded Kepler's work as too open-minded, which is likely what was being referred to here. UpdateNerd (talk) 08:52, 26 July 2020 (UTC)

Bhaskarcharya

The article that you uploaded has been already debunked since it has nothing to do with gravity.see David Wilson talk page of bogus claim of bhasaracharya to learn more. Obiwana (talk) 11:05, 15 January 2023 (UTC)

Bogus claim of bhasaracharya

The property of attraction is inherent in the Earth. By this property the Earth attracts any heavy unsupported thing towards it: The thing appears to be falling [but it is in a state of being drawn towards the Earth]." But there's nothing here, or anywhere else in his writings about "the earth, planets, constellations, moon, and sun" being "held in orbit due to this force." In fact, in the very same work, Bhaskaracharya states unequivocally that the Earth remains stationary in the heavens and is encompassed by the orbits of the Moon, Sun, planets and stars, so he cannot have even believed that the Earth itself had any orbit to be held in. Credit to David Wilson see his talk page and if you still love doing so then we are going to remove you for the charge of vandalism Obiwana (talk) 11:06, 15 January 2023 (UTC)

That's why I had removed the article Obiwana (talk) 11:20, 15 January 2023 (UTC)

Bhaskarcharya and Surya siddhanta

There is a error on your link since Surya siddhanta was written in 505CE and bhaskaracharya was born in 11l2th century it has nothing to do with him. Obiwana (talk) 11:18, 15 January 2023 (UTC)

Reply to Obiwana about Bhaskaracharya

Dear Obiwana, first of all please assume good faith, we have never interacted before and it was my first edit on this specific topic. A sentence such as Credit to David Wilson see his talk page and if you still love doing so then we are going to remove you for the charge of vandalism feels honestly quite offensive. However, I prefer not to take it personally and just focus on the facts.

Just a sidenote: You don't need to create 3 topic titles for the same conversation. Also, please let's keep this conversation under one title, you could reply underneath my message and use a colon (:) for indenting the message.

Just to make it clear, Bhaskaracharya actually refers to multiple people who have lived in history, however there are two often confused Bhaskaracharyas (or Bhaskaras) as they are both invaluable mathematicians. The older Bhaskaracharya, also known as Bhāskara I lived approximately between 600 – 680 CE. And the "younger" Bhaskaracharya, aka Bhāskara II lived approximately between 1114 – 1185 CE.

If you look at the information I added in the article (check here), I didn't even mention the Surya Siddhanta, but the Siddhānta Shiromani which is composed by Bhaskara II in 1150. The links I provided (as well as other sources) confirm the quotation, it is in the volume called Goládhyáyah, chapter III-Bhuvanakośa. If anyone can read Bengali, Devanagari and Gujarati scripts, there are also Sanskrit originals of his work in those scripts.

I want to make it further clear that I don't have any agenda with this subject, I actually came across this topic pretty recently and I don't have any favourites, I just want to contribute to the subject as neutrally as possible. While researching it, I did come across some bogus theories, none of it I support. However, just because some people misquote and use wrong data while trying further their ideas, doesn't mean everything they say has to be wrong. For example, if I say kangooroos live in Australia and Australia is in North America, that's bogus – but only the part that says Australia is in N. America. Someone can still use reliable sources to independently prove that kangooroos live in Australia.

We are talking here about the History of Gravitational Theory in the chapter of Antiquity, where so many Greco-Roman philosophers are mentioned for their own understanding about or related to gravity. If your reason for removing Bhaskaracharya is that his gravitational theory wasn't complete, so are all of the other quoted philosophers and sages of the past. For consistency, we have to either remove them all, or none. Alternatively, we can – as the article tries to establish – try to summarise as best possible, the chronicles of how, the understanding of gravity has been furthered in history until the modern times.

Furthermore, I couldn't find any User:David Wilson to check his talk page. There is one User:David Wilson Raja.P whose talk page hasn't been created yet. If you mean the talk page of an article called David Wilson, there are tons of articles by that name, which would take an enourmous amount of time to check one by one. You didn't provide me with any link. And I had sourced the information you removed in the article. Sourced information in the right place, written with a neutral language should not be removed without due consideration. So, for all these reasons, and to better the article, I'm adding it back. Sorry for the wall of text. Humbly Universal Life (talk) 23:15, 15 January 2023 (UTC)

Go to the bogus quotation of bhasaracharya list you will find out why did he removed it Obiwana (talk) 01:45, 16 January 2023 (UTC)