Answer: Ancient India not only attracted religious scholars and philosophers from around the world, but several mathematicians and scientists as well, such as Al-Uqlidisi, Al-Khwarizmi and Al-Kindi, who visited India, learned Indian mathematics and propagated them to the West. The ten mathematical symbols (0,1,2,3…) are known as Arabic numerals to the world, but Mathematics/Geometry itself in Arab is called ‘Hindsa,’ (meaning ‘from India’). Ancient Indian mathematicians and their contributions:

• Baudhayan: His work, Sulva-Sutra (1st millennium BC), contains the formula for calculating the area of triangle (later called Pythagoras theorem), value of pi and square root of two, along with several other formulas of trigonometry.
• Aryabhatta: His work ‘Aryabhatiya’ (5th century CE), described the algorithm of calculating square and cubic roots using the decimal number system. He gave an almost accurate value of pi, showing that zero was not only a numeral but also a symbol and a concept. He also showed that ‘Earth is round and rotates on its own axis’, the moon and the planets shine due to reflected sunlight and gave a scientific explanation for solar and lunar eclipse.
• Brahmagupta: In his methods of multiplication, Brahmagupta used place value in almost the same way as it is used today. He introduced negative numbers and operations on zero into mathematics. He wrote Brahma Sputa Siddhanta through which the Arabs came to know the Indian mathematical system.
• Bhaskaracharya: He wrote ‘Siddanta Shiromani’ wherein he introduced Chakrawat Method or the Cyclic Method to solve algebraic equations. This method was rediscovered six centuries later by European mathematicians, who called it the inverse cycle.
• Mahaviracharya: He wrote Ganit Sara Sangraha in 850A.D., which is the first textbook on arithmetic in present day form. The current method of solving Least common Multiple (LCM) of given numbers was also described by him, long before John Napier.

Ancient Indian scientists and their contributions:

• Kanad: He was a sixth century scientist of Vaisheshika School. According to him, the material universe is made up of kanas (atom) which cannot be seen with naked eyes and are indivisible and indestructible.
• Varahamihira: He propounded earthquake cloud theory in his Brihat Samhita (6th Century), wherein he discussed signs of earthquakes; tried to relate earthquakes to the influence of planets, undersea activities, underground water, unusual cloud formation and abnormal behaviour of animals.
• Nagarjuna: A 10th Century alchemist, he succeeded in making an element with gold-like shine. This technology is used now in making imitation jewellery. In his treatise, Rasaratnakara, he has discussed methods for the extraction of metals like gold, silver, tin and copper.
• Susruta: Born around 700 BCE, he invented surgical procedures such as Rhinoplasty and removal of cataract. His treatise Susruta Samhita covers more than 1100 diseases, 760 plants and method of selecting and preserving a dead body for the purpose of its detailed study
• Charaka: He is considered as the father of ancient Indian science of medicine. His Charak Samhita has the description of a large number of diseases and gives methods of identifying their causes as well as the method of their treatment. He was aware of the fundamentals of Genetics in 2nd Century.
• Patanjali: The Yoga-Sutra of Patanjali, identified mental and emotional illness in addition to physical illness, and suggested its cure with the help of Yoga and Ayurveda.

Due to poor documentation of the works of ancient Indian mathematicians and scientists, and a setback in the research and development work during medieval times, the contribution of these Indian scholars did not find the place they deserved.