India has a rich intellectual heritage that spans millennia. It is as old as the Ṛgvedic Period (3300-1900 BCE), during which Indian civilisation laid the foundation for advancements in diverse scientific domains. The Vedas, Itihāsas, Brāhmaṇas, Āraṇyakas, Upanishads, and Purāṇas, not only delved into philosophical and spiritual realms but also contained profound insights into mathematics, astronomy, medicine, and more.
It will require an entire book to elaborate on all the mathematics, science and technology born in India. Nevertheless this article points to some of the most important achievements in the field of mathematics, astronomy, medicine, and metallurgy in which the ancient Indian scholars, often known as sages or poets, excelled.
In the field of mathematics, the decimal system was the most significant which impacted the entire world. This discovery involves decimal place value system, the use of zero as a number and the notation of zero while writing numbers. Brahmagupta (598-668 CE) elaborated on the rules of arithmetic using zero. The concept of zero as a numeral and as a placeholder in positional notation was a groundbreaking idea. Indian mathematicians, such as Aryabhata (476-550 CE), played a crucial role in defining the properties of zero. The Brahmi numerals are today known as Hindu-Arabic numeral system.
Ancient Indian mathematicians made advancements in algebra and trigonometry. Aryabhata’s work named Āryabhatiya contained solutions to quadratic equations. He introduced trigonometric functions in the context of astronomy. Trigonometry was used to construct fire altars in various shapes like bird (Garuda) shape, as described in texts like Yajurveda. Baudhāyana (800-740 BCE), provided an approximation for the value of pi in the form of the ratio of the circumference to the diameter of a circle. The Baudhāyana Śulba Sūtra states the famous rule:-
दीर्घचतुरस्रस्याक्ष्णया रज्जुः पार्श्वमानी तिर्यग् मानी च यत् पृथग् भूते कुरूतस्तदुभयं करोति ॥
The diagonal of an oblong produces by itself both the areas which the two sides of the oblong produce separately. This rule is known today as the Pythagorean Theorem. Baudhāyana discovered it much earlier than Pythagoras.
Śulba Sūtras contains rules for constructing various Vedic fire-altars in various geometric shapes. This demonstrates a profound understanding of geometry. Mādhava of Saṃgama Grāma (1340-1425 CE) and the Kerala School mathematicians discovered the infinite series expansions for trigonometric functions. They are the foundation of calculus. The Jesuit missionaries learned this mathematics from Kerala scholars and propagated in Europe. Isaac Newton (1642-1726) learned it from them.
There are references in the Vedic literature about Vaidyuti (electricity). It is often understood as a force with the potential for shock or spark, which can also create light. The manipulation of metals, including the creation of alloys, indirectly contribute to the understanding of electrical conductivity. Many texts like Rāmāyaṇa and Mahābhārata make mention of ‘Yantras’ which is understood as complex machines, often employed in warfare. Yantras are often attached to the walls of fortresses. They can strike multiple number of enemies. Śataghni is a Yantra which can kill hundred enemies at a time. Other Yantras like Ṭāṭṭālaka (turret), Kaca Grahaṇi (hair-grasper), Uṣṭrika (camel shaped catapults), Huḍa Śṛṅgika, Huḍāguḍa and Yantrajāla too are frequently mentioned in the Itihāsas. Most of these are mentioned in Vana Parva of Mahābhārata in the battle of Kṛṣṇa with the king of Śālva.
Vimānas of various complexity are mentioned in the Itihāsas. Often, they are described as flying vehicles, though a Vimāna could also mean the tall tower of a building. The poet of Mahābhārata reports the arrival of a Vimāna to take Arjuna from Himālaya as follows (MBH 3.43.3-6):- “Removing the darkness from the sky and splitting the clouds, it made a thundercloud like sound. It had Asi (swords), Śakti (spears), fearsome Bhīma Gada (huge clubs) and Prāsa (lances) with divine power. It had Vidyuta (lightning) flashes. It had Huḍāguḍa with Cakra (wheel). It had Vāyu Sphoṭa – implements that created bursts of winds. It produced sounds of Barhi (peacocks) and clouds. It had terrible and huge Nāgas with glowing mouths, tall as white clouds and hard as rocks.”
Here, the swords, spears clubs and lances could be objects like antennas and globular structures. Huḍāguḍa with Cakra and Vāyu Sphoṭa could be its main engine with air compression chambers and thrusters, that eject gas for maintaining thrust. High pitched sounds (peacock sound) and low-pitched heavy sounds (sounds of clouds: – thunder cloud or cloud-burst) could be various sounds of the engine. What is described as Nāgas could be external coils and wires of the vehicle.
The binary system is evident in the ancient Indian text Chandah Śastra of Piṅgala (3rd or 2nd century BCE), a treatise on prosody, which used binary representations for the poetic meters. Binary system is the foundation of today’s computers and electronics. Neither electronics nor computer science were possible without the Indian discovery of zero and the decimal system. In linguistics, the study of languages, the ancient Indians did pioneering work with texts like Nirukta (etymology) and Vyākaraṇa (grammar). This study is what led to the creation of etymology and grammar to all languages of the world. The development of computer programming languages is indebted to these fields of knowledge developed by ancient Bhāratīyas.
The Bhagavat Yāna episode in Udyoga Parva of Mahābhārata describes the Viśvarūpa of Kṛṣṇa. The poet mentions Kṛṣṇa showing the 30 (Tridaśa) Devatas including Brahma, Rudra, Lokapālas, Ādityas, Sādhyas, Vasus, Aśvins, Indra, Maruts and others as thumb-sized holograms (MBH 5.129.4). They were radiant as fire! This description resembles the digital hologram technology used in today’s Augmented Reality and Virtual Reality, broadly described as Extended Reality. Similar descriptions are seen in Bhīṣma Parva, as part of Bhagavad Gita where Kṛṣṇa showed Viśvarūpa to Arjuna.
The contributions in astronomy were equally remarkable. Āryabhata proposed a heliocentric model of the solar system in Āryabhatiya. He suggested that the earth rotates on its axis and provided calculations for the positions of the planets in a heliocentric framework. Ancient Indian astronomers developed precise methods for calculating the positions of celestial bodies. The Siddhāntas, astronomical treatises, provided mathematical models for planetary motion, eclipses, and the positions of stars. The Indian calendar system, known as the Pañchāṅga, was developed to accurately measure time, celestial events, and festivals. Pañca Siddhāntika of Varāhamihira (505-587 BCE) discussed various methods for calculating calendar dates based on planetary positions.
Ancient Indian astronomers used ecliptic coordinates, a system for locating celestial objects along the ecliptic plane. The Surya Siddhanta described the measurement of celestial longitude and latitude. the division of the celestial sphere into lunar mansions, or Nakshatras, played a significant role in Indian astronomy. These divisions were used for timekeeping, especially in the context of lunar and solar calendars. Ancient Indian astronomers were skilled observers. They documented celestial events such as eclipses, comets, and the positions of planets, contributing to a growing body of astronomical knowledge. Such observations, recorded in the texts like Vedāṅga Jyotiṣa, Rāmāyaṇa and Mahābhārata aid in dating the events mentioned in these texts or dating the text itself, after normalising it with other disciplines like archaeology.
Indian astronomy had a profound impact on Islamic astronomy during the medieval period. Scholars like Al-Biruni studied Indian texts and incorporated Indian astronomical methods into Islamic traditions. Through them, Indian astronomy also influenced the European astronomy.
Indians made profound contributions to what we today call physics. The Vaiśeṣika Sūtra dated to between 6th to 2nd century BCE is a work of Kaṇāda. It had some early insights into the Newtonian laws of motion. However, it was not formalised into a formal theorem with mathematical formulas like Newton has done. Bhaskara II (1114-1185 CE) proposed the idea of gravity, recognising that objects are attracted towards the Earth due to a force. It was an early insight to the gravitational laws, few centuries before Newton.
Surya Siddhantha included discussions on optics and the nature of light. It explained the phenomenon of refraction and correctly described the apparent motion of the sun caused by the Earth’s axial tilt. The Nātya Shastra, an ancient Indian treatise on performing arts attributed to Bharata Muni, contained insights into acoustics. It discussed the principles of sound, including the classification of musical instruments based on their sound-producing mechanisms. Brahmagupta made contributions to fluid dynamics by discussing the nature of liquids and the formation of waves. His work included insights into the behaviour of fluids in motion. The concept of atoms (Aṇu) is found in early Indian philosophical texts like the Vaiśeṣika Sūtras. These texts proposed the idea of indivisible particles as fundamental building blocks of matter. It served as the philosophical basis for the atomic theory, which later developed into formal theorems in Europe, backed with mathematical formulation.
Later, this Classical Physics transitioned into Quantum Physics. The philosophical foundation for Quantum Physics is seen in Vedanta. The philosophy of Vedanta, quite similar to Quantum Physics, posits that the observer influences what is observed. In other words, the mind with its act of observation collapses the abstract probabilistic quantum superpositions and creates the concrete reality. Correspondingly, the Advaita Vedanta insists that it is our mind that creates our reality – viz, this observable universe. Similar to Advaita Vedanta, Quantum Physics is nearing the conclusion of universal Oneness of the multiplicity apparently observed by the observer.
Indian contribution to chemistry is numerous, especially in metallurgy. The Copper Age in India started by 4000 BCE, Bronze Age by 3300 BCE, Iron Age in 2000 BCE. Ancient Indian artisans were skilled metallurgists, and their expertise is evident in the extraction and processing of metals. The iron pillar in Delhi, dating back to the Gupta period (4th-5th centuries CE), is a remarkable example of advanced metallurgical knowledge, showcasing corrosion resistance and a mastery of ironworking techniques. The ancient Indian tradition of chemistry was known as Rasa Śastra. It involved the systematic study of minerals and metals for medicinal and transmutational purposes. Texts such as the Rasa Ratnākara and Rasa Kāmadhenu provided detailed instructions on the preparation of various chemical compounds, including alloys, acids, and medicines. The Arabs translated these as alchemy texts.
Ancient Indian metallurgists were skilled in creating metal alloys. Artha Śastra, mentions methods for alloying metals and describes techniques for testing the purity of metals. This knowledge was crucial for ensuring the quality of metal products. The development of alloys, such as bronze (copper and tin) and brass (copper and zinc), played a crucial role in various industries, including sculpture, coinage, and tool manufacturing. Copper was widely used in ancient India for making tools, utensils, and decorative items. Bronze, an alloy of copper and tin, was employed to create durable and corrosion-resistant artefacts.
Gold and silver were extensively used in ancient Indian art and jewellery. Skilled artisans crafted intricate ornaments and artefacts using techniques like repoussé, filigree, and granulation. Metal was used in architectural elements such as pillars and gates. The exquisite detailing on metalwork in temples and palaces reflects the craftsmanship of ancient Indian metallurgists.
Ancient Indian metallurgists were proficient in various casting techniques. The lost-wax casting method was commonly used for creating intricate metal sculptures, particularly during the period of the Chola dynasty (9th-13th centuries CE). India has a long history of metal coinage, with various dynasties issuing coins made of copper, silver, and gold. These coins were often adorned with symbols and inscriptions, showcasing the metallurgical skill of the time.
Ancient Indian texts describe various methods of salt production, highlighting a practical understanding of chemical processes. The Artha Śastra, of Chanakya (4th century BCE), detailed techniques for extracting salt from saline water and soil. The ancient Indians were skilled in glass making, and the use of glass vessels is mentioned in various texts. Additionally, dyeing techniques for textiles involved chemical processes, and the knowledge of plant-based dyes and mordants was well-established. Ancient agricultural practices involved the use of various chemical processes. Artha Śastra provided guidance on soil fertility, irrigation, and the use of organic and inorganic substances for enhancing agricultural productivity.
Ayurveda, the ancient Indian system of medicine, incorporated principles of chemistry in the preparation of medicines. Charaka and Sushruta, ancient medical scholars, documented the properties of various substances, including minerals and plant extracts, and their therapeutic uses. The Ayurvedic pharmacopoeia included processes like distillation and sublimation. The ancient Indian system of taxonomy, as found in texts like the Jīvaka Chintāmaṇī, categorised living organisms into various classes based on their characteristics. This classification system included divisions such as plants, animals, and microorganisms.
Ancient Indians had a comprehensive understanding of plants and their medicinal properties. The Ṛgveda contains references to various plants used for medicinal purposes, and later texts like the Nighantu explored plant classifications and their therapeutic applications. The Panchatantra and other ancient texts included study of animals (zoology)—observations of animal behaviour and characteristics. Artha Śastra discussed wildlife management, wildlife resources and conservation. The Sushruta Samhit” contains insights into embryology, describing the development of the foetus in the womb. It includes discussions on various stages of foetal growth and the formation of organs. Artha Śastra deals with the study of insects (entomology). It provided information on insects and their impact on agriculture. The text suggests measures for pest control and emphasises the importance of understanding insect behaviour.
Suśruta, was an ancient Indian physician and surgeon. His Suśruta Samhita (6th century BCE) was a comprehensive treatise on medicine and surgery. It is one of the earliest known works on surgery. It covers a wide range of topics, including anatomy, surgical instruments, and various surgical procedures. The Suśruta Samhita contains detailed descriptions of various plastic surgery procedures, including reconstruction of the nose (rhinoplasty) and repair of torn earlobes. Suśruta’s techniques for skin grafting and reconstructive surgery were remarkably advanced for the time. The Suśruta Samhita describes surgical procedures for cataract removal. Ancient Indian surgeons used a curved needle to push the opaque lens aside and allow light to enter the eye, a technique known as couching. Suśruta emphasised the importance of understanding human anatomy for successful surgical interventions. The text provides details on the dissection of cadavers to study anatomy, showcasing a profound commitment to empirical observation.
Ancient Indian surgeons were skilled in setting fractured bones and treating dislocations. The Suśruta Samhita outlines various methods for bone-setting, including the use of splints and braces. The Suśruta Samhita mentions the use of wine and other substances to induce a state of anaesthesia during surgery. While the methods might not align with modern anaesthesia practices, the recognition of the need for pain management during surgical procedures is noteworthy. The ancient Indian surgeons used a variety of surgical instruments, many of which are described in detail in the Suśruta Samhita. These instruments included scalpels, forceps, needles, and specialised tools for specific surgical procedures. The importance of cleanliness and hygiene in surgical practices is emphasised in the Suśruta Samhita. Ancient Indian surgeons recognised the significance of maintaining a sterile environment to prevent infections. The use of herbs, Yoga, and meditation for healing purposes reflects the integration of physical and mental well-being in ancient Indian medical practices.
India’s maritime knowledge is evident in Artha Śastra. It provided guidelines for shipbuilding, navigation, and trade. The existence of maritime trade routes between India and other civilisations underscores the proficiency of ancient Indian sailors and navigators. The term Navi and navigation has its origin in the Sanskrit term Nāvam (meaning boat or ship). Indians were foremost ship builders. Indian ships travelled in Indian Ocean and reached the shores of Africa and South East Asia. Ancient Indians had trade relationships with Greece, Rome and China both through land and sea.
The concept of environmental conservation, as seen in the reverence for nature in various scriptures, reflects a deep ecological understanding. Practices such as water harvesting, afforestation, and sustainable agriculture were embedded in ancient Indian societal norms. Ancient Indian were excellent city builders and town planners. Water management with excellent sanitation and drainage system with flush toilets, concealed or underground water pipelines, public baths, interior bathrooms, water canals, well paved rectangular roads, four-squares and buildings are evident in the Harappan city planning. The Harappan Civilisation is named as such since the first settlement of this civilisation was found in Harappa. Its geographical span is now understood as Western UP in the east, Eastern Afghanistan in the west, Jammu and Kashmir in the north and Northern Maharashtra in the south. This vast region of North West India was watered by the rivers – Sarasvati, Sindhu and Narmada. Hence, it is to be more aptly renamed as Sarasvati Sindhu Narmada Civilisation (SSNC).
A need exists now, to record and reclaim India’s ancient scientific knowledge. We have been taught that everything that is science emerged from the Western world. This is simply not true. Hence, India’s scientific achievements from ancient times need to be made part of the curriculum and syllabus of the schools and colleges. Some Western universities now acknowledge that the theorems like Pythagoras Theorem was discovered by Indian scholars. Yet, these simple truths are not properly taught to Indian students. This situation needs to change. Indians need to proactively read their ancient texts and understand the scientific information contained therein, through primary sources. This will help them to think and develop modern applications of our ancient knowledge, or at the minimum, it will inspire them to be pioneers in scientific discoveries and technological innovations.
Dharma Digital is a platform initiative of this author, which focuses on blending Generative AI with Digital Hologram Technology of Extended Reality. Through this platform, more than hundred interactive 3D digital holograms of Devatas like Indra, Viṣṇu, Śiva, Brahma, Sarasvati, Pārvatī, Lakṣmī, Rāma, Sīta, Hanumat, Ganeśa, Skanda, Ayyappa, Kṛṣṇa along with Pāṇḍavas and Pāñcālī are created.
These Devata Holograms are thumb-sized, as is mentioned in the Viśvarūpa Darśana and Bhagavat Yāna episodes of Mahābhārata! They glow in their own light. They can appear in the real world and are capable of conversing with us using Generative AI. They can walk with us, smile at us or interact with us. They can be used to teach the students about concepts of Sanātana Dharma. Dharma Digital platform can also recreate ancient personalities like Aryabhata and Bhāskara who can teach the ancient scientific knowledge of India to today’s generation in an interactive and intimate way. They can work as knowledge Gurus, and guides for the young generation.
These knowledge Gurus can reside in their mobile phones or their Augmented Reality and Virtual Reality devices. They can be invoked into the real world as and when required, to guide our new generations.
Figure: Dharma Digital Holograms rendered on a table.
I also similarly note the development in creating software tools by other technology experts to help bring the ancient scientific knowledge of India to the current generation. These include Sanskrit-to-Indian-language translation and Sanskrit-to-English translation using Panini’s grammar rules. Similarly, the text-to-speech software can read and speak Sanskrit text and the speech-to text software can convert spoken Sanskrit to Sanskrit text. Such tools will help in the learning of Sanskrit through daily conversation. Pāṇini’s Sanskrit can be used as a bridge language between machine language and human language. Research in this area has seen some progress, after a recent discovery about a simplifying principle of Pāṇini’s grammar. These developments can easily bring back the ancient Indian knowledge to the current generation, and inspire them to improve them and apply them into the field of electronics, Virtual Reality (VR), Artificial Intelligence (AI), Space etc.
Author Brief Bio: Jijith Nadumuri Ravi is a former space scientist with ISRO. He is the author of the book ‘Rivers of Ṛgveda’ and ‘Geography of Rāmāyaṇa’. At ISRO he contributed to the Chandrayan 1 GSO-LTO orbit design, and the GSLV launches D2, F01, and F02. He founded the website AncientVoice (ancientvoice.wikidot.com). It contains 25,376 pages on Mahābhārata, Rāmāyaṇa, Vedas and Purāṇas, and has Bhāratavarṣa maps, analysis articles, lineage charts, analysis of 16,000 plus nouns, data illustrations and paintings. Naalanda and Takshasila are the sister sites of AncientVoice, focusing on the Upaniṣads and Greek, Avestan and Tamil literature. Jijith founded the platform Dharma Digital (dharmadigital.in) with 100 plus self-made Metaverse ready 3D digital holograms to promote Dharma using digital technologies like Virtual Reality and Artificial Intelligence.
 It was the Arabs who popularised it in Europe.
 The term algebra is Arabic since the Arabs popularised it in Europe
 The current version of Surya Siddhantha we get to read is dated to 4th or 5th Century CE