Monday, May 2, 2011

Not Newton but Bhashkaracharya

Who Discovered the Law of Gravitation?
Bhashkaracharya had discovered the law of gravitation well before Newton did some thousand years later.

१) Gravitational Pull—“Father, the earth on which we live, rests on which thing?”
Leelavati had asked this question hundreds of years ago to her father, Bhaskaracharya. In reply, Bhaskaracharya said, “O daughter, Leelavati! Those people who say that the earth is resting on the sheshnaag (cobra snake), the tortoise or elephant or any other thing, are wrong. If we accept that it is based on something, then the question that arises is, that thing rests on which thing? Thus, the reason and its reason…if this sequence continues, then it is known as a state of uncondition in jurisprudence.” Leelavati still insisted on asking the question. Then, Bhaskaracharya said , “Why can we not accept that the earth is not based on anything? What is wrong in saying that the earth is standing on its own strength and call it its power of retention?” At this Leelavati asked how it was possible? Then, Bhaskaracharya speaks of principles and says that the power of things is very peculiar.
Marucchalo bhoorachala swabhaawato
yato Vichitravatavastu shaktyah
—(Siddhant Shiromani Golaadhyay-Bhuvankosh—5)
He further says:
Aakrishtishaktishch mahi taya yat
khastham Guru swabhimukham swashaktya.
Aakrishyate tatpatateev bhaati
Samesamantaat kwa patatviyam khe.
—(Siddhanta Shiromani Golaadhyay-Bhuvankosh—6)
आकृष्टिशक्तिश्च महि तय यत्
खष्ठं गुरु स्वभिमुखं स्वशक्त्या ।
आकृष्यते तत्पततीव भाति
समेसमन्तात् क्व पतत्वियं खे ॥
—(शिद्धान्त शिरोमणि गोलाध्यय-भुवनकोष-६)
This means that the earth has the power of attraction. So, it attracts heavy things towards itself and because of the attraction, they fall to the ground. But, when an equal power or strength pulls from all directions in the sky, then how can a thing fall? This means that the planets stay in the sky without any support because the gravitational powers of the various planets maintain the balance.
Today, we say that Newton was the first to discover the gravitational power of the earth, but 550 years before him, Bhaskaracharya had spoken about it.
२) The Earth is Round—Leelavati asks her father how he can say that the earth is round when she can see only a flat surface all around?
Bhaskaracharya says that what we see is not always the truth. He says that if you draw a large circle and look at only a hundredth part of its circumference, then it will appear to be a straight line; but actually it is not so. It is curved. Similarly, we see only a small part of the sphere of this huge earth. Hence, it seems flat to us. In reality, the earth-is round.

Samo yatah syaatparidheh shataanshah
Prithvi cha prithvi nitaraam taneeyaan
Narashcha tatprishthagatasya kritsnaa
Sameva tasya pratibhaatyatah saa.
—(Siddhanta Shiromani golaadhyay-Bhuvankosh 13)
समो यत: स्यात्परिधेह शतान्श:
पृथी च पृथ्वी नितरां तनीयान् ।
नरश्च तत्पृष्ठगतस्य कृत्स्ना
समेव तस्य प्रतिभात्यत: सा ॥
—(सिद्धन्त शिरोमणि गोलाध्यय-भुवनकोष- १३)

Saturday, October 31, 2009

State management with ASP.NET

Dear friends! Here is summary of my today's technical presentation "State Management with ASP.NET". Here "State" means not political region; in web development preserving user's information during the visit of web site is referred as "State management".....http:// (Hyper Text Transfer Protocol) is connection less protocol. Every page in a web application is independent; while developing web application it is difficult to preserve user's supplied information; because we can not directly read the content of one web forms text box while working on another web form.By using "State" management technique we can establish connection in a connection less environment (http://).
ASP.NET provides state management that saves information between pages, which helps to maintain the continuity of user information (sate) through out a visit to a web site. here are two types of state management technique: 1. Server side 2. Client side 1. Server Side State management by using >> I) Application II) Session and III) Database Server/ State Server2. Client Side State management >> I) Cookies II) ViewState property and III) Query String
Session and Cookies are used to maintain security in web site. In ASP.NET Microsoft Forms based authentication mechanishim is most commonly used. It is based on cookies.
In Cookies based authentication after verifying User credentials (User Name, Password etc.) ASP.NET sends valid authentication cookie to the users' machine. If valid cookie is present in user's machine then secure page (Inbox of e-mail) will be sent to client the computer.
Cookies are less reliable then server side state management because user can delete cookies and few amount of data (4 KB) can be stored.