A COMPARATIVE STUDY OF ATOMIC THEORY ON THE BASIS OF PHYSICS AND PHILOSOPHY
Introduction
Science and philosophy were both highly developed disciplines in ancient India. However, Indian philosophic thought was considerably more mature and traditionally we misunderstand that any early scientific contributions came only from the west, particularly from Greece. Because of this erroneous belief, which is perpetuated by a wide variety of scholars, it is necessary to briefly examine the history of Indian scientific thought. Grant Duff British Historian of India said that 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. It is true that India has given us extraordinary gifts like grammar and logic, philosophy and fables, hypnotism and chess, and above all numerals and decimal system.
To their credit the Indians have made great strides in the study of numbers and of geometry. They have acquired immense information and reached the zenith in their knowledge of the movements of the stars (astronomy). Sir William Wilson Hunter author of the book, “The Indian Empire”, said that India has even contributed to modern medical science by the discovery of various chemicals and by teaching you how to reform misshapen ears and noses. Ancient Indians measured the land, divided the year, mapped out the heavens, traced the course of the sun and the planets through the zodiacal belt, analyzed the constitution of matter, and studied the nature of birds and beasts, plants and seeds. India's contribution to the sciences of mathematics and medicine has been unique. In other sciences, especially linguistics, metallurgy, and chemistry, Indians made trail-blazing discoveries. India has a much more realistic view of the matter. It says
“Who knows for certain? Who shall here declare it?
Whence was it born, whence came creation?
The gods are later than this world’s formation;
Who then can know the origins of the world?
None knows whence creation arose;
And whether he has or has not made it;
He who surveys it from the lofty skies,
Only he knows- or perhaps he knows not”.
It is understood that the Indian philosophy has contributed some scientific facts, but it is to be evaluated on what capacity these scientific points are still valid in this era of high technology. So in this paper we are going to have a comparative study of atomic theory on the basis of physics and philosophy.
Vaishesika theory of atomism
India developed very early, enduring atomist theories of matter. Possibly, Greek atomistic thought was influenced by India, via the Persian civilization. Kanaada, the founder of the Vaishesika system of philosophy, expounded that the entire matter in this world consists of atoms as many in kind as the various elements. Kanaada said that the cause of creative motion is believed to be adrsta, unseen moral force which guides the destiny of souls according to their karma and requires them to be provided with properly equipped bodies and an appropriate objective world for the experience of pleasure and pain. It is due to the operation of this metempirical force that atoms start moving to get together in order that they may be integrated into countless varieties of things. Although the Vaishesika system developed independently from the Nyaya, the two eventually merged because of their closely related metaphysical theories. In its classical form, however, the Vaishesika school differed from the Nyaya in one crucial respect: where Nyaya accepted four sources of valid knowledge, the Vaishesika accepted only perception and inference. Vaishesika atomism also differs from the atomic theory of modern science: according to the Vaishesikas, the functioning of atoms was guided or directed by the will of the Supreme Being. This is therefore a theistic form of atomism. Kanaada was an expounder of the law of causation and of the atomic theory. He classified all the objects of creation into nine elements, namely: earth, water, light, wind, ether, time, space, mind and soul. According to his theory every object of creation is made of atoms, which in turn are joined with each other to form molecules.
This statement is very similar to the John Dalton’s atomic theory proposed after 2500 years. Kanaada has also described the dimension and motion of atoms and their chemical reactions with each other. In Vaiseshika philosophy, Kanaada (600 B. C) claimed that elements could not be destroyed. Kanaada's theory stated that basic particles mix together as the building blocks for all matter. It is true that the atomic theories of ancient India are brilliant imaginative explanations of the physical structure of the world. Some Jain thinkers went a step further. They thought that all atoms are the same kind and variety emerged because they entered into different combinations. Kanaada thought that light and heat are variations of the same reality. Umasvati, who lived in the first century A.D., suggested that atoms of opposite qualities alone combined and the atoms attracted or repelled, as they were heterogeneous or homogenous.
John Dalton's Atomic theory
In 1804 Dalton, put forward his atomic theory according to which all matter was composed of very small particles called atoms. All atoms of a given element are identical. The atoms of a given element are different than those of any other element. Atoms of one element can combine with atoms of other elements to form compounds. A given compound always has the same relative numbers of types of atoms. Atoms are indivisible in chemical processes. Atoms are not created or destroyed in chemical reactions. A chemical reaction simply changes the way atoms are grouped together.
Prout’s atomic theory
Prout, a contemporary of Dalton proposed that all the substances were made of hydrogen atoms because the study of the atomic weights of the various substances seemed to indicate that they were simple multiples of the atomic weight of hydrogen. The atomic view of matter was further supported by the successful development of the kinetic theory of gases which is based on the assumption that the atoms of a gas act as elastic and impenetrable solid spheres, exerting no force upon one another except at the time of collision. This theory leads to the correct interpretation of heat and temperature and is able to derive all the gas laws on the above assumptions.
J.J.Thomson atom model
After Eugen Goldstein’s 1886 discovery that atoms had positive charges, J.J.Thomson proposed in 1898 an atom model that the atom was supposed to be sphere filled with positively charged matter of uniform density in which just sufficient numbers of electrons were embedded to balance the positive charge. Since the electrons placed within the positive charge resembled the plums in a pudding the atom model is some times referred to as plum pudding model. The electrons were further supposed to possess vibratory motion about their equilibrium position so as to account for the emission of light. When no light was being emitted the electrons were supposed to be at rest.
Rutherford atom model
In 1908, Ernest Rutherford, a former student of Thomson's, proved Thomson's plum pudding structure incorrect. Rutherford and his two associates Geiger and Marsden performed a series of experiments with radioactive alpha particles. Rutherford fired tiny alpha particles made up of positively charge particles, at solid objects such as gold foil. He found that while most of the alpha particles passed right through the gold foil, a small number of alpha particles passed through at an angle, and some bounced straight back like a tennis ball hitting a wall. Rutherford's experiments suggested that gold foil, and matter in general, had holes in it! These holes allowed most of the alpha particles to pass directly through, while a small number ricocheted off or bounced straight back because they hit a solid object.
In 1911, Rutherford proposed a revolutionary view of the atom. He suggested that the atom consisted of a small, dense core of positively charged particles in the center (or nucleus) of the atom, surrounded by a swirling ring of electrons. The nucleus was so dense that the alpha particles would bounce off of it, but the electrons were so tiny, and spread out at such great distances that the alpha particles would pass right through this area of the atom. Rutherford's atom resembled a tiny solar system with the positively charged nucleus always at the center and the electrons revolving around the nucleus. The positively charged particles in the nucleus of the atom were called protons. Protons carry an equal, but opposite, charge to electrons, but protons are much larger and heavier than electrons. In 1932, James Chadwick discovered a third type of sub-atomic particle that he named the neutron. Neutrons help stabilize the protons in the atom's nucleus. Because the nucleus is so tightly packed together, the positively charged protons would tend to repel each other normally. Neutrons help to reduce the repulsion between protons and stabilize the atom's nucleus. Neutrons always reside in the nucleus of atoms and they are about the same size as protons. However, neutrons do not have any electrical charge, they are electrically neutral. Atoms are electrically neutral because the number of protons (+ charges) is equal to the number of electrons (- charges) and thus the two cancel out. As the atom gets larger, the number of protons increases, and so does the number of electrons (in the neutral state of the atom).
Atoms are extremely small. One hydrogen atom (the smallest atom known) is approximately 5 x 10-8 mm in diameter. Atoms of different elements are distinguished from each other by their number of protons (the number of protons is constant for all atoms of a single element, the number of neutrons and electrons can vary under some circumstances). To identify this important characteristic of atoms, the term atomic number (z) is used to describe the number of protons in an atom. For example, z = 1 for hydrogen and z = 2 for helium. Another important characteristic of an atom is its weight, or atomic mass. The total number of protons and neutrons in the atom roughly determines the weight of an atom. While protons and neutrons are about the same size, the electron is more that 1,800 times smaller than the two. Thus the electrons' weight is inconsequential in determining the weight of an atom: it's like comparing the weight of a flea to the weight of an elephant.
Niels Bohr atom model
Ernest Rutherford's view of the atom consisted of a dense nucleus surrounded by freely spinning electrons. In 1913, the Danish physicist Niels Bohr proposed yet another modification to the theory of atomic structure based on a curious phenomenon called line spectra. Bohr hypothesized that electrons occupy specific energy levels. When an atom is excited, such as during heating, electrons can jump to higher levels. When the electrons fall back to lower energy levels, precise quanta of energy are released as specific wavelengths (lines) of light.
Under Bohr's theory, an electron's energy levels, also called as electron shells can be imagined as concentric circles around the nucleus. Normally, electrons exist in the ground state, meaning they occupy the lowest energy level possible, the electron shell closest to the nucleus. When an electron is excited by adding energy to an atom (for example, when it is heated), the electron will absorb energy, 'jump' to a higher energy level and spin in the higher energy level.
After a short time, this electron will spontaneously 'fall' back to a lower energy level, giving off a quantum of light energy. Bohr not only predicted that electrons would occupy specific energy levels; he also predicted that those levels had limits to the number of electrons each could hold. Under Bohr's theory, the maximum capacity of the first (or innermost) electron shell is two electrons. For any element with more than two electrons, the extra electrons will reside in additional electron shells. For example, in the ground state configuration of lithium (which has three electrons) two electrons occupy the first shell and one electron occupies the second shell.
Conclusion
Commenting on the theories of atomism in philosophy, L Basham remarks that Indian atomic theories were not of course, based on experiment, but on intuition and logic. Vaishesika theory of atomism says that every object of creation is made of atoms and when they are joined with each other to form molecules. Kanaada has also described the dimension and motion of atoms and their chemical reactions with each other. In Vaishesika philosophy, Kanaada (600 B. C) claimed that elements could not be destroyed. Kanaada's theory stated that basic particles mix together as the building blocks for all matter. These statements are very similar to the John Dalton’s atomic theory. But Vaishesika atomism differs from the atomic theory of modern science: according to the Vaishesikas, the functioning of atoms was guided or directed by the will of the Supreme Being. This is therefore a theistic form of atomism. In Physics there is no question of theism and only experiments are giving way to many theories of atom. Dalton’s theory, Prout’s theory, Thomson’s theory, Ruther ford’s theory, Bohr’s theory, Sommerfeld’s theory, Vector atom model, Liquid drop model and shell model are all based on experimental evidences. Though Vaishesika theory of atomism in philosophy has been predicated based on some logic, it has given an idea about an atom before 2500 years. The atomic theories developed in physics within 200 years based on experiments lead to scientific developments namely nuclear fission, nuclear fusion, artificial transmutation of elements namely artificial radio-isotopes, atom bomb, hydrogen bomb, nuclear energy nuclear power, nuclear medicine and many more. Hence, at least we can accept the statement given by Grant Duff British Historian of India that 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.
References
Chidambara Kulkarni, Indian History and Culture, Orient Longman Ltd. 1974. (268).
D.P.Singhal, India and World Civilization, Macmillan India Ltd, 1993 (153 - 188).
S.Natarajan, Indian Culture, Indo-Middle East Cultural Studies Hyderabad, 1960, (68).
Jawaharlal Nehru, The Discovery of India, Oxford University Press. 1995(216).
Swami Tattwananda, Ancient Indian Culture At A Glance, Oxford Book Co. 1962 (127).
K.Ilangovan, Engineering Physics, Anuradha Agencies, Kumbakonam (1987).
Jadunath sinha, Indian Philosophy, New Central book agency, Kolkata.
Introduction
Science and philosophy were both highly developed disciplines in ancient India. However, Indian philosophic thought was considerably more mature and traditionally we misunderstand that any early scientific contributions came only from the west, particularly from Greece. Because of this erroneous belief, which is perpetuated by a wide variety of scholars, it is necessary to briefly examine the history of Indian scientific thought. Grant Duff British Historian of India said that 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. It is true that India has given us extraordinary gifts like grammar and logic, philosophy and fables, hypnotism and chess, and above all numerals and decimal system.
To their credit the Indians have made great strides in the study of numbers and of geometry. They have acquired immense information and reached the zenith in their knowledge of the movements of the stars (astronomy). Sir William Wilson Hunter author of the book, “The Indian Empire”, said that India has even contributed to modern medical science by the discovery of various chemicals and by teaching you how to reform misshapen ears and noses. Ancient Indians measured the land, divided the year, mapped out the heavens, traced the course of the sun and the planets through the zodiacal belt, analyzed the constitution of matter, and studied the nature of birds and beasts, plants and seeds. India's contribution to the sciences of mathematics and medicine has been unique. In other sciences, especially linguistics, metallurgy, and chemistry, Indians made trail-blazing discoveries. India has a much more realistic view of the matter. It says
“Who knows for certain? Who shall here declare it?
Whence was it born, whence came creation?
The gods are later than this world’s formation;
Who then can know the origins of the world?
None knows whence creation arose;
And whether he has or has not made it;
He who surveys it from the lofty skies,
Only he knows- or perhaps he knows not”.
It is understood that the Indian philosophy has contributed some scientific facts, but it is to be evaluated on what capacity these scientific points are still valid in this era of high technology. So in this paper we are going to have a comparative study of atomic theory on the basis of physics and philosophy.
Vaishesika theory of atomism
India developed very early, enduring atomist theories of matter. Possibly, Greek atomistic thought was influenced by India, via the Persian civilization. Kanaada, the founder of the Vaishesika system of philosophy, expounded that the entire matter in this world consists of atoms as many in kind as the various elements. Kanaada said that the cause of creative motion is believed to be adrsta, unseen moral force which guides the destiny of souls according to their karma and requires them to be provided with properly equipped bodies and an appropriate objective world for the experience of pleasure and pain. It is due to the operation of this metempirical force that atoms start moving to get together in order that they may be integrated into countless varieties of things. Although the Vaishesika system developed independently from the Nyaya, the two eventually merged because of their closely related metaphysical theories. In its classical form, however, the Vaishesika school differed from the Nyaya in one crucial respect: where Nyaya accepted four sources of valid knowledge, the Vaishesika accepted only perception and inference. Vaishesika atomism also differs from the atomic theory of modern science: according to the Vaishesikas, the functioning of atoms was guided or directed by the will of the Supreme Being. This is therefore a theistic form of atomism. Kanaada was an expounder of the law of causation and of the atomic theory. He classified all the objects of creation into nine elements, namely: earth, water, light, wind, ether, time, space, mind and soul. According to his theory every object of creation is made of atoms, which in turn are joined with each other to form molecules.
This statement is very similar to the John Dalton’s atomic theory proposed after 2500 years. Kanaada has also described the dimension and motion of atoms and their chemical reactions with each other. In Vaiseshika philosophy, Kanaada (600 B. C) claimed that elements could not be destroyed. Kanaada's theory stated that basic particles mix together as the building blocks for all matter. It is true that the atomic theories of ancient India are brilliant imaginative explanations of the physical structure of the world. Some Jain thinkers went a step further. They thought that all atoms are the same kind and variety emerged because they entered into different combinations. Kanaada thought that light and heat are variations of the same reality. Umasvati, who lived in the first century A.D., suggested that atoms of opposite qualities alone combined and the atoms attracted or repelled, as they were heterogeneous or homogenous.
John Dalton's Atomic theory
In 1804 Dalton, put forward his atomic theory according to which all matter was composed of very small particles called atoms. All atoms of a given element are identical. The atoms of a given element are different than those of any other element. Atoms of one element can combine with atoms of other elements to form compounds. A given compound always has the same relative numbers of types of atoms. Atoms are indivisible in chemical processes. Atoms are not created or destroyed in chemical reactions. A chemical reaction simply changes the way atoms are grouped together.
Prout’s atomic theory
Prout, a contemporary of Dalton proposed that all the substances were made of hydrogen atoms because the study of the atomic weights of the various substances seemed to indicate that they were simple multiples of the atomic weight of hydrogen. The atomic view of matter was further supported by the successful development of the kinetic theory of gases which is based on the assumption that the atoms of a gas act as elastic and impenetrable solid spheres, exerting no force upon one another except at the time of collision. This theory leads to the correct interpretation of heat and temperature and is able to derive all the gas laws on the above assumptions.
J.J.Thomson atom model
After Eugen Goldstein’s 1886 discovery that atoms had positive charges, J.J.Thomson proposed in 1898 an atom model that the atom was supposed to be sphere filled with positively charged matter of uniform density in which just sufficient numbers of electrons were embedded to balance the positive charge. Since the electrons placed within the positive charge resembled the plums in a pudding the atom model is some times referred to as plum pudding model. The electrons were further supposed to possess vibratory motion about their equilibrium position so as to account for the emission of light. When no light was being emitted the electrons were supposed to be at rest.
Rutherford atom model
In 1908, Ernest Rutherford, a former student of Thomson's, proved Thomson's plum pudding structure incorrect. Rutherford and his two associates Geiger and Marsden performed a series of experiments with radioactive alpha particles. Rutherford fired tiny alpha particles made up of positively charge particles, at solid objects such as gold foil. He found that while most of the alpha particles passed right through the gold foil, a small number of alpha particles passed through at an angle, and some bounced straight back like a tennis ball hitting a wall. Rutherford's experiments suggested that gold foil, and matter in general, had holes in it! These holes allowed most of the alpha particles to pass directly through, while a small number ricocheted off or bounced straight back because they hit a solid object.
In 1911, Rutherford proposed a revolutionary view of the atom. He suggested that the atom consisted of a small, dense core of positively charged particles in the center (or nucleus) of the atom, surrounded by a swirling ring of electrons. The nucleus was so dense that the alpha particles would bounce off of it, but the electrons were so tiny, and spread out at such great distances that the alpha particles would pass right through this area of the atom. Rutherford's atom resembled a tiny solar system with the positively charged nucleus always at the center and the electrons revolving around the nucleus. The positively charged particles in the nucleus of the atom were called protons. Protons carry an equal, but opposite, charge to electrons, but protons are much larger and heavier than electrons. In 1932, James Chadwick discovered a third type of sub-atomic particle that he named the neutron. Neutrons help stabilize the protons in the atom's nucleus. Because the nucleus is so tightly packed together, the positively charged protons would tend to repel each other normally. Neutrons help to reduce the repulsion between protons and stabilize the atom's nucleus. Neutrons always reside in the nucleus of atoms and they are about the same size as protons. However, neutrons do not have any electrical charge, they are electrically neutral. Atoms are electrically neutral because the number of protons (+ charges) is equal to the number of electrons (- charges) and thus the two cancel out. As the atom gets larger, the number of protons increases, and so does the number of electrons (in the neutral state of the atom).
Atoms are extremely small. One hydrogen atom (the smallest atom known) is approximately 5 x 10-8 mm in diameter. Atoms of different elements are distinguished from each other by their number of protons (the number of protons is constant for all atoms of a single element, the number of neutrons and electrons can vary under some circumstances). To identify this important characteristic of atoms, the term atomic number (z) is used to describe the number of protons in an atom. For example, z = 1 for hydrogen and z = 2 for helium. Another important characteristic of an atom is its weight, or atomic mass. The total number of protons and neutrons in the atom roughly determines the weight of an atom. While protons and neutrons are about the same size, the electron is more that 1,800 times smaller than the two. Thus the electrons' weight is inconsequential in determining the weight of an atom: it's like comparing the weight of a flea to the weight of an elephant.
Niels Bohr atom model
Ernest Rutherford's view of the atom consisted of a dense nucleus surrounded by freely spinning electrons. In 1913, the Danish physicist Niels Bohr proposed yet another modification to the theory of atomic structure based on a curious phenomenon called line spectra. Bohr hypothesized that electrons occupy specific energy levels. When an atom is excited, such as during heating, electrons can jump to higher levels. When the electrons fall back to lower energy levels, precise quanta of energy are released as specific wavelengths (lines) of light.
Under Bohr's theory, an electron's energy levels, also called as electron shells can be imagined as concentric circles around the nucleus. Normally, electrons exist in the ground state, meaning they occupy the lowest energy level possible, the electron shell closest to the nucleus. When an electron is excited by adding energy to an atom (for example, when it is heated), the electron will absorb energy, 'jump' to a higher energy level and spin in the higher energy level.
After a short time, this electron will spontaneously 'fall' back to a lower energy level, giving off a quantum of light energy. Bohr not only predicted that electrons would occupy specific energy levels; he also predicted that those levels had limits to the number of electrons each could hold. Under Bohr's theory, the maximum capacity of the first (or innermost) electron shell is two electrons. For any element with more than two electrons, the extra electrons will reside in additional electron shells. For example, in the ground state configuration of lithium (which has three electrons) two electrons occupy the first shell and one electron occupies the second shell.
Conclusion
Commenting on the theories of atomism in philosophy, L Basham remarks that Indian atomic theories were not of course, based on experiment, but on intuition and logic. Vaishesika theory of atomism says that every object of creation is made of atoms and when they are joined with each other to form molecules. Kanaada has also described the dimension and motion of atoms and their chemical reactions with each other. In Vaishesika philosophy, Kanaada (600 B. C) claimed that elements could not be destroyed. Kanaada's theory stated that basic particles mix together as the building blocks for all matter. These statements are very similar to the John Dalton’s atomic theory. But Vaishesika atomism differs from the atomic theory of modern science: according to the Vaishesikas, the functioning of atoms was guided or directed by the will of the Supreme Being. This is therefore a theistic form of atomism. In Physics there is no question of theism and only experiments are giving way to many theories of atom. Dalton’s theory, Prout’s theory, Thomson’s theory, Ruther ford’s theory, Bohr’s theory, Sommerfeld’s theory, Vector atom model, Liquid drop model and shell model are all based on experimental evidences. Though Vaishesika theory of atomism in philosophy has been predicated based on some logic, it has given an idea about an atom before 2500 years. The atomic theories developed in physics within 200 years based on experiments lead to scientific developments namely nuclear fission, nuclear fusion, artificial transmutation of elements namely artificial radio-isotopes, atom bomb, hydrogen bomb, nuclear energy nuclear power, nuclear medicine and many more. Hence, at least we can accept the statement given by Grant Duff British Historian of India that 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.
References
Chidambara Kulkarni, Indian History and Culture, Orient Longman Ltd. 1974. (268).
D.P.Singhal, India and World Civilization, Macmillan India Ltd, 1993 (153 - 188).
S.Natarajan, Indian Culture, Indo-Middle East Cultural Studies Hyderabad, 1960, (68).
Jawaharlal Nehru, The Discovery of India, Oxford University Press. 1995(216).
Swami Tattwananda, Ancient Indian Culture At A Glance, Oxford Book Co. 1962 (127).
K.Ilangovan, Engineering Physics, Anuradha Agencies, Kumbakonam (1987).
Jadunath sinha, Indian Philosophy, New Central book agency, Kolkata.
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