I. Introduction
Seldom perhaps, in Modern India a work in science was so much in tune with the evolving and articulate social and economic needs of the people of this country. C. V. Seshadri’s* questioning of the 2nd law of thermodynamics and his formulation of new concepts to serve the genuine needs is a path breaking exercise which is sure to be of great consequence. He has focused attention on the degrading and enslaving nature of this law of physical science, and shown in what sense the biases it incorporates have devastating consequences for, particularly, the people of the Third World. This law states that nature degrades spontaneously and, as we shall see, like a self-fulfilling prophecy it itself becomes the chief instrument of such degradation.
Although so far Seshadri is alone in his scientific exercises, he is in good company in the developing radical intellectual and political atmosphere in the country. His critique of modern science and technology is in essential continuity with Mahatma Gandhi's critique of modernity or modern Western Civilization, and can thus be seen as a part of the fresh awakening among our intellectuals and social theorists in comprehending the civilizational essence of Gandhi's critique of modernity. Two efforts of great consequence that belong to this fresh awakening should be mentioned here. One is the peasant movement, which is amounting to effective questioning of every modern concept, type and ideal and is at the same time laying down a sound basis for new construction. Another is the emerging new intellectual awakening which, while seeking an understanding of the real nature of pre-colonial Indian society, is laying the foundations of an indigenous forward looking philosophy. This new awakening also has a component that is systematically questioning and exposing the biases, assumptions and interests hidden in the philosophy and practice of modern Western science and technology and is thus making the critique of modernity total. C.V. Seshadri through his work on Thermodynamics, is taking this critique of modern science and technology one step further—towards the construction of alternative concepts and theories.
Thermodynamics, as the name suggests, deals with the relations of heat with mechanical work. At any rate investigations into such relation, viz. Conversion of heat energy into useful mechanical energy, constitute the beginning of this huge area of physics in the middle of the 19th century in Europe. It constitutes the basis of energetics so popular and so useful today in the tasks of science policy and development planning. Through the previous century and more thermodynamics has undergone great extension and refinement. It has been given an axiomatic formulation and generalised treatment leading even to the inclusion of dynamics under it. Originally developed as a theory of macro systems and processes independent of the hypothesis of the atomic structure of matter, most of its laws and concepts have been given a consistent interpretation in terms of molecular, atomic and subatomic motions. Its basic concepts have been subjects of fierce debates and a certain type of questioning of their validity has led to what is called non-equilibrium thermodynamics.
However, I am saying all this only to add that in this examination we shall not worry about any of this but concentrate only on the gross aspects of thermodynamics which fix a gauge for making energy-quality and give a certain criteria of efficiency, both being widely used in energy and development planning. So, first we shall devote some space to discuss the relation between development and efficiency or energetics and then go on to give a relatively popular exposition of the 2nd law of thermodynamics which is the villain of the piece. This is then followed by a critical appreciation of Seshadri’s contentions viz. (i) that concepts of thermo-dynamics have a Western bias being rooted in the culture and commerce of the place of their origin, (ii) that 2nd law of thermodynamics is an energy-quality marker giving a concept of efficiency which is a guide to the utilisation of resources to the grave detriment of the poor and generally all those who are outside the modern structure of opportunities in a country like India, (iii) that, this 2nd Jaw in fact is not only parochial but patently false and (iv) that there is need for the development of new energy-quality markers in the interest of the poor and the subjugated. Seshadri, in fact suggests a new concept of ‘Shakthi’ which is discussed in the Appendix to this article.
II. Development and Efficiency :
‘Development’ is the 20th century God-literally every thing happens in its name. The expert. believes, and the non-expert has been made to believe, that all developmental activity based on modern science and technology necessarily leads to an enhancement in the efficiency of utilisation of resources viz. money, men and materials. This however happens to be patently untrue, as will be argued presently.
Let us consider the question of economic efficiency of modern production practices. It is generally believed that the Industrial Revolution of the West made production of commodities cheaper, meaning that modern industry is economically more efficient than the processes it displaces. This is simply not true. Production of cloth by 19th century European mills was always more expensive than handspun cloth of India. It won out in competition solely because of stringent government policy of physical and fiscal controls. Even today if all factors are taken into consideration the mill can be shown to be economically less efficient than charkha or handloom. In fact all modern technique is cost intensive. Whether it is agriculture based on modern implements and chemical fertilizers, transport by automobile, railway or aeroplane, making of steel in giant steel mills, production of electricity by nuclear power plants or catching of fish by large mechanised trawlers, each one of these has a much higher input-output ratio than the process it replaces. This will be particularly obvious when disorganisation of the traditional sector that it necessarily causes is also taken into account. This makes these processes economically less efficient. When confronted with such argument the modern expert is likely to concede, though grudgingly and only to point out that such processes, however, are labour saving, meaning that they have greater human efficiency, that is, in them small human effort leads to greater result. But this is not true either.
Modern development affects adversely the efficiency of human effort in general bringing about a decline in the productivity of labour. As a rule a more developed production process means that smaller number of people will be required to conduct the business. But also as a rule such a change in the name of development causes damaging disorganisation of the existing ways of doing things adversely affecting the work and output of a large number of people. If we do not merely consider the men and women who find a place for ‘work in the modern industry but take into account the work of all those deployed in ancilliary or preparatory work from construction of buildings to waste disposal and specific raw material industry and also all those affected in the entire process of change, then it is highly unlikely that change over to modern processes will involve increase in productivity of labour or efficiency of human effort.
Having lost out on the fronts of economic and human efficiencies the modern expert may take recourse to energy efficiency. This is to say that modern processes make a more efficient utilisation of energy contained in the natural resources. That is, these processes in the final analysis, make available greater amounts of energy in the usable form. But this too has been seriously contested.
For example, a recent study comparing the modern energy resources (coal, petroleum, hydel) and the traditional ones (firewood, dung animal) has come to the conclusion that in the context of India modern energy resources are not intrinsically better than traditional ones, rather its opposite is the case1. Neither in terms of availability, nor in terms of cost of development, nor in terms of efficiency of utilisation do modern energy resources appear superior to the traditional ones.
The Green Revolution has been consistently attacked for not actually bringing about any increase in aggregate productivity inspite of being so cost intensive. This is being known to and accepted by more and more people but relatively little known is the fact that modern agriculture very often is energetically less efficient than traditional practices by a factor of 100 or 200. A.K.N. Reddy made this revalation when he showed (in the EPW, Annual Number, 1976) that while some traditional technologies required one calorie of input for fifty calories of output, the modern agriculture requires four to five calories of input for one calorie of output. Such researches are still marginal, for they say things which totally contradict the political and scientific establishments and not because there is any difficulty in establishing such energy relationships.
So, after all, modern and developed processes are not more efficient when all factors are taken into account. But it should be conceded too that they appear more efficient when a limited view is taken. And this limited view is based on a systematic approach. We have it when we limit our vision only to the modern sector and do not take into reckoning effect on non-modern structures, sectors and peoples. Modern science and technology produces riches for a few, it equips them with greater know!edge, makes their efforts more productive and gives them processes which are energetically more efficient.
But the expert on energetics believes that there is actual development and that such development is based on a genuine increase in the energy efficiency of new processes. He is backed in his belief by laws of science. This is the 2nd law of thermodynamics which gives shape to a concept of energy quality and efficiency. These concepts thus assume an infallible status and govern development planning. It is their neutrality and veracity which is challenged by Seshadri. Before proceeding further. it is therefore necessary to take a closer look at what exactly thermodynamics is saying.
III. Thermodynamics
The essence of thermodynamics is captured in two basic laws. The first law states that energy can neither be created nor destroyed. Taking account of the interconvertibility of mass and energy discovered later, this law amounts to a statement of mass-energy conservation principle. It can be said to give a quantitative shape to the concept of energy. Questions.of quality of different energies and constraints on their transfer and conversion are what the second law deals with.
The second law has been stated in great many ways, all such statements being roughly equivalent to one another. For example a clear statement due to Kelvin says that : ‘In a cycle of processes it is impossible to transfer heat from a heat reservoir and convert it all into work, without at the same time transferring a certain amount of heat from a hotter to a colder body2. A neat and precise formulation of this ‘law by Carathéodory is said to be exact and capable of giving all the mathematical consequences. It states that : Arbitrarily near to any given state, there exist states which cannot be reached from an initial state by means of adiabatic processes3. These statements have the merit of bringing out the fact that transfers of heat are central to thermodynamics.
There is another important point about 2nd law that it is associated with some kind of one wayness. For instance, it is a consequence of Carethedory’s version of this law, that there exist states A and B such that one can go from A to B by an adiabatic process but cannot come back from B to A without involving heat transfers.
Another, class of formulations is around the concept of entropy and degradation. Thomson (later Lord Kelvin) first formulated the law as the existence in nature of a universal tendency towards the degradation of mechanical energy2. It is contended that the second law entails that all natural processes increase entropy, that is disorder, in the universe making it less and less potent in terms of source of useful energy. A precise statement of the 2nd law in terms of entropy would be that an isolated system spontaneously gravitates towards a maximum entropy State. This is same as saying that in any process the entropy of the composite system, which consists of the system and its surroundings always increases. The entropy formulation of the second law brings into focus the monotonic degradation of the universe.
The second law of thermodynamics provides definitions of energy efficiency and energy-quality through the device of the ideal heat engine (for eg. the Carnot engine). Working along ideal reversible paths, this engine absorbs heat Q1 from a source at temperature T1 does work W, and rejects heat Q2 to a sink at temperature T2. Assuming the source and the sink to be infinite, this ideal engine has an efficiency of 1 - T2 /T1, and since neither the source can be at infinite temperature nor the sink at absolute zero temperature, the efficiency of even this ideal engine cannot be hundred per cent.
So, 2nd jaw not only states that when heat is converted into work some heat must necessarily flow from a hotter to a colder body, but also it sets limits to the efficiency of such conversion as a function of temperature. Since in practice T2 is the atmospheric temperature, the way to achieve higher efficiencies becomes attainment of higher temperatures.
This also leads us to a concept of energy-quality. This follows from the fact that all of heat energy available in a particular setting or context cannot be converted into useful work, part of it becomes unavailable in the process of conversion. This rejected unavailable heat is of lower quality, in fact useless, if the temperature at which it is rejected is the ambient temperature. It should be obvious because no heat engines can be made to work with source at the ambient temperature. If such an engine was to fruitfully operate the sink temperature should be lower than the ambient, production of which will, it can be shown, consume more. useful work than which could be obtained from such an engine.
The entropy formulation says that from an ordered situation when useful work is obtained, the initial situation runs down or degrades itself to produce disorder. And this resulting disorder is useless from the point of view of obtaining further useful work. So as we harness useful work, the universe runs down to thermal states of greater and greater disorder and eventually to the so called ‘heat death’.
IV. Biases of Thermodynamics
There is great need to reflect on the supposedly universal nature of modern science. When laws of thermodynamics were formulated a great debate ensued because they appeared to bring in man and his needs into the formulation through concepts like useful work and unavailable energy. Mechanics, the then existing paradigm of physical theory, had a formulation which seemingly was independent of human beings and their needs. So, anthropomorphic nature of thermodynamics became a matter of concern. But, anthropomorphism incorporates elements of ethnocentrism and this becomes obvious when in the debate we have participants from different cultures of the world. Seshadri exhibits a deep sense of this when he writes that’ . . . when Newton believed that space and God were synonymous he was merely following a well-rooted tradition of the religions of the Middle East. This is one example of the many anthropomorphisms in science and technology. We recognise.that all human constructs are anthropomorphic ; obviously this is not what is meant. What is implied is, many concepts which are accepted as absolutely self-evident once stated or as arriving.out of a ‘scientific method’ are really based on very deep seated cultural roots that need not necessarily be universal; consequently they become very difficult to stream into the consciousness of the practising engineer who does not share the traditions.15
Discussions with Seshadri reveal that in his view concepts of science invariably carry their birth marks. By this one is not referring to the subjectivity of the scientist who formulates the new theories and concepts. It is important to note that theories or laws of science generally come to be formulated in such terms and in such language which is different from its first appearance. This only means that personal idiosyncracies or preference of individuals get cancelled out or eliminated during the course of a new formulation which ordinarily takes at least a generation. What one means is that it is the culture, religion, history, lifestyles, the way of thinking and the needs of the society where scientific concepts are born, which have their way into the content of these concepts.
Proper concept in this context is ‘Civilisation’. The content and usefulness of science, as of anything else, is circumscribed by civilisational parameters, Be it classical mechanics, electrodynamics, quantum theory or thermodynamics they are all subject to this constraint. For the purpose of convenience let us divide our discussion of thermodynamics in this context into cultural, mechanical and economic beasis of thermodynamics.
Cultural Bias
Although the final formulation of the law of thermo-dynamics did not use theological terms the argument invoked and the line of reasoning adopted owed a lot to theological concepts. The concepts of energy and entropy owed much to the larger cultural traditions of the West. When one goes through the developments based on the contributions of Fourier, Joule, Clausius, Thomson, Helmholtz Maxwell and others one gets a feeling that there is constant attempt at a secularisation of the new ideas. But strictly speaking this is not secularisation but only an attempt at mathematical formulation and mechanical explanation, the cultural and theological contexts of the society having their full role to play in shaping the basic ideas. Obviously such roles as these are they can hardly be identified in a causal nexus. Bur histories and social explanations do not use a causal or hypothetico - deductive model of explanation.
William Thomson who may be credited with the first formulation of the 2nd law as well as considerable refining of the concept of ‘energy’, often takes recourse to theological and cosmological justifications. For example Thomson declared in a paper of 1852 that “as it is most certain that creative power alone can either call: into existence or annihilate mechanical energy”, dissipated energy cannot be annihilated, only transformed. The creation of energy and the restoration of energy dissipated in irreversible processes are thus acts which can only be performed by divine agency6
When a scientist uses God or Divine Power and finally produces a neat mechanical or mathematical model, there is tendency to ignore the former or make a schizophrenic analysis of the thought process of the scientist. Both these are a result of seeing God as a vacuous concept, a redundancy. It happens due to a false tendency of universalisation which modern science has done much to strengthen. For non-believers God may be just a supra-natural concept devoid of all content but for believers it is simply not. so, for them it is either a Christian
God or Islamic God or Hindu God etc.. depending upon their religion. And this ‘parochial’ God is not vacuous by any means. In fact, secularists are as much part of the cultural traditions of a society as the believers are. For example take the humanist trend in Europe at the turn of the 18th century. Humanism is in essence that way of thinking which refuses to accept the supra-natural or super-human. Understood as such it looks like an idea which may be applicable in any society. But then we realise that European humanism is against the Christian supra-human which it considers oppressive and dehumanising. What if the Hindu or Islamic supra-human is not oppressive or dehumanising? So, reference to God by scientist is no vacuous reference to a non-existing generality, but a real and operative reference to a particular historical-cultural tradition, in this case Christianity. This point is directly borne out in case of entropy.
As is well known ‘William Thomson . . . saw the dissipation of energy as implying a progressivisit cosmogeny, an idea that harmonised with the biblical view of the transitory character of the universe’.7 Concept of time did assume a great importance as a consequence of the 2nd law. Monotonic increase in entropy brought into existence an arrow of time. The incessant degradation of energy in the universe made return in time impossible. Since this was not so in mechanics a physicist qua physicist found it difficult to comprehend. But it was the physicist belonging to the European tradition who had given shape to it.
Look at what Prigogine has to say : “Thomson thus made a dizzy leap from engine technology to cosmology. His formulation of the second law was couched in the scientific terminology of his time : the conservation of energy, engines, and Fourier’s law. It is clear, moreover, that the part played by the cultural context was important. It is generally accepted that
the problem of time took on a new importance during the nineteenth century. Indeed, the essential role of time: began being noticed in all fields in geology, in biology, in language, as well as in the study of human social evolution and ethics. But it is interesting that the specific form in which time was introduced in physics, as a tendency toward homogeneity and death, reminds us more of ancient mythology and religious archetypes than of the progressive complexification and diversification described by biology and the social sciences. The return of these ancient themes can be seen as a cultural repurcussion of the social and economic upheavals of the time’.8
Can there be any doubt that Indian Scientists qua Indians may not find much by way of inspiration from such concepts of energy and time? Indian tradition perhaps does not disjoint mass and energy, it perhaps has a different concept of birth and death which suits a different concept of time than the linear ‘arrow time’. What is there in thermodynamics which could give dynamism to the Indian scientists and engineers?
Mechanical Bias
The mechanical bias operates at two levels ; one, at the level of interpretation of thermodynamic theory and another, at the level of object of thermodynamics.
Helmholtz first formulated the energy conservation principle on the assumption of the universal validity of the mechanical theory of nature developed after Newton's work. His main work was in physiology of organisms where he wanted to show that forces which governed the physiology of organisms were explained in terms of the laws of mechanics.9 Mechanical equivalence of heat and theory of interconvertibility of heat and mechanical energy were great steps forward from the point of view of the programme of mechanical explanation. But irreversibility posed problems. Development of the kinetic theory of gases solved much of the difficulty. Temperature was shown to be proportional to the kinetic energy of the speeding molecules of a gas. So this provided the basis for seeing heat in terms of a statistical and probabilistic formulation of the microscopic world. But in a way the problem of sources of irreversibility persisted and still persists.
This programme of mechanical explanation as applied to thermodynamics was quite in tune with the object of thermodynamics itself. Useful work was a central concept. When heat engines were the chief practical pre-occupations, thermodynamics worried about mechanical work, gaseous state and high temperatures. What should be bothersome is how such limited concern could be said to lead to universal theories. Most processes in the word, at least those of human concern which humans can control and manage, take place at ordinary temperatures and in liquid and solid states also. Nature of thermodynamic theory and analysis is what it is because of total preoccupation with processes which produced mechanical work. Such processes were also chosen selectively as we shall shortly see. The economic bias was perhaps more compelling than any other.
Economic Bias
Heat engines are the first of the modern machines, they mark the beginning of modern industry. It is this industry which made Europe prosper at the cost of people all over the world. So, this was the industry of useful work and high efficiency. 19th century Eurape had within its power to produce high temperature (by burning coal) so thermodynamics never bothered about what makes it possible to attain the high temperature, it only bothered about how to obtain work by using. bodies at high temperature. And this too had to be work of a special type which could be put into services of the economic power. Only such mechanical work was useful work which could be harnessed for the production of marketable commodities.
A contemporary analogy may make it clear. Consider the research going on for increasing agricultural productivity. It has produced high yielding varieties of seeds, the chemical fertilizers, insecticides etc. Such a package of new practices is said to increase agricultural production, but what necessarily happens along with it is that this increased production must be controlled by the state and not the farmers. Strategy of the Government is not to increase overall agricultural production but to increase only controllable production. Witness the market arrivals, the graneries and the hungry millions in the rural areas. In a similar vein thermodynamics studied only the production of useful work which was controllable. For why otherwise it pays scant attention to say processes of monsoon formation in which billions of tons of sea water evaporate and travel great distances doing enormous amount of work at the ambient, atmospheric temperature, to form clouds. Rain, no doubt even today, is infinitely more important than heat engines. Why is it that thermodynamics has no interest in the formation of coal and petroleum which make the high temperature possible? So, it is an insult to nature to say that thermodynamics is an attempt to study nature and formulate laws of its governance; in fact, it seems to study only those processes which can be controlled and put in the service of the economic powers.
Its ‘unblushing economic tinge’10 as a science has been noted, but the argument was never pushed to its logical conclusion. Seshadri should be credited for doing this an exercise to which we turn in the next section.
V Energy as Value
Seshadri and Balaji have demonstrated that the second law of thermodynamics mainly serves as a guide-line for extraction of resources and their utilisation. Moreover it can be seen to follow necessarily from the formulation of the concepts of energy and efficiency that such utilisation is against the interest of, and disorganises the life of, the people outside the modern sector only to promote and fulfill the needs of the modern-sector. They write: By its very definition energy becomes available only through a conversion process and according to the “most supreme” law of entropy, a portion of energy is always lost in such process. Further, under restricted conditions, the loss can be minimised and realisation of such condition is, therefore, essential for operating a process efficiently. At this level, the concept, viz energy, cannot be viewed separate from its use and itself becomes criterion for deciding the value of resources for utilisation in processes at hand. Energy becomes a quality marker in resource utilisation in the same way that money becomes a marker in exchange’62
How such a perception of energy as value leads to usurpation of resources from the non- industrial sector is shown by the following examples :11
(a) Use of wood for cooking is energetically wasteful. Since the modern industry can make more efficient use of wood, forests and their produce should be exclusively in the service of the industrial sector. What disastrous consequence this view has had on the people of the non-industrial sector of this country during the last hundred years, is rather well documented.
(b) Food has value only as energy, and as its production (viz agriculture) and ingestion are ambient temperature processes, it is also energy of the lowest quality. Food thus occupies a low priority in the eyes of energetics and development planning.
(c) It is more efficient to convert molasses into alcohol for industrial use than into yeast that has food value for humans and animals.
(d) Sugarcane should be converted into white sugar instead of gur, even though fatter may be nutritionally superior and capable of being produced in small low cost units in the villages themselves.12
What these examples show is that energy-quality considerations favour a modern industrial process at the cost of the food consumption needs of the people on a large scale. This is so because according to the second law of thermodynamics, biological processes are energy conversion processes of very little significance since they occur at the ambient. In fact the energy criterion of the second law does not merely disfavour food and nutrition oriented processes, but also favours inorganic chemical fertiliser against organic natural fertiliser, production and use of cement against the traditional lime mortary production of cloth in the mills against hand spun cloth, etc. That all inputs into modern agriculture (fertilizers, pesticides, machinery, etc) are products of high temperature processes, or more generally high gradient processes, or that the recent interest in solar energy is primarily towards using it to achieve high temperatures - all these follow quite logically. The point is that this energy criterion fits neatly to serve a particular kind of arrangement of things and men, viz the internal colonial set up.13 Modern energetics is only a tool to allocate resources so as to promote modern industry and modern life styles at enormous cost to those outside the modern structures.
Quite in tune with energy as value guiding the actual transfer of resources, at another level energetics biases the scientific workers for investigations only in particular directions. In the wake of the 1973 Arab-Israel war and the resulting shift in the control of the oil-fields to the Arab nations, leading to the so called energy crisis, the American Physical Society (APS) appears to have felt constrained to remind the scientists of what constituted the measure of energy quality. Seshadri quotes a statement sponsored by the APS :14 ‘From the perspective of the second law, organised coherent motion is most precious, very high (and very low) temperature is next most precious and heat at a temperature near ambient (luke warm, cool) is degraded energy’, and ‘The reference is to work (rather than heat) because work is the highest “quality” form of energy equivalent to, heat at infinite temperature’. So we note that after more than a century and a half since the first heat engine appeared in Europe, mechanical work and mechanistic interpretations still occupy the centre stage. Perhaps it only shows the continued domination and arrest of a particular industrial mode. The importance of the high temperature is simply related to the fact that high temperature processes minimise entropy change, it being inversely proportional to temperature. (Entropy change is expressed by a q/T expression). More simply, perhaps, the importance of temperature can be seen from the expression of energy efficiency of an ideal heat-engine. It is1-
where the engine absorbs heat at T1 and does work rejecting part of it to sink at T2, normally the atmospheric surroundings. So this makes attainment of high temperatures a -key to making greater mechanical work available. This is quite a compelling guide for résearch into and development of new processes.
VI. Conceptual and Methodological Falsities of Thermodynamics
The concept of an ‘isolated system’ or isolability is central to the formulation of the second law of thermodynamics. Recollect its statement that isolated systems spontaneously change to the entropy maximum state. Also the concept of unavailability or lowering of energy quality of degradation or the universe are realisable or understandable only through formulations which use the concept of an isolated system.
Seshadri contends that a way of identifying the false content of the second law of thermodynamics is to recognise that strictly speaking isolability is not conceivable, meaning that isolated systems are not possible even in principle.15
Sometimes it may appear that basic thermodynamic formulations are carried out without recourse to isolability. But if one looks deeper it will be found that certain other assumptions are made which are. equivalent to the assumption of isolability. For example take the ideal Carnot engine operating between a heat source at temperature T1 and a heat sink at temperature T2 whose efficiency is given by the expression 1. This ideal engine is not supposed to be an isolated system because it enters into heat exchanges with the source and the sink. But an additional assumption is involved, namely that these heat exchanges bring about no changes in the source or the sink. This makes it possible for the Carnot engine to go through a reversible cycle with zero change in entropy, something that can happen only for isolated systems. Imaginative thought experiment is an important and legitimate tool of discovery in science. But such thought experiments as that due to Carnot are not imaginative but imaginary. What with conceptualisation of heat reservoirs of infinite capacity unaffected by finite transfers of heat to and from them? It is such conceptualisation which makes concepts like unavailable energy possible. In real processes the heat source is obtained generally by burning fossil fuels, coal, petroleum etc., and the sink is the atmosphere. And it is changes in the atmosphere (earth included) which makes construction of heat sources possible. Is not this rejected heat, called unavailable energy, in part responsible for coming into existence of fossil fuels over long periods of time? Processes at the ambient i.e. T2, make attainment of T1 possible. High energy-quality is possible only because of processes of low energy quality. But the thermodynamicist will reply saying that we have started talking about real systems wheres the isolated system is an ideal case.
But to say that no systems are isolable is not only to maintain the trivia that in practice no systems can be isolated but to make a substantial theoretical point that ‘isolated system’ is a wrong kind of idealisation leading to erroneous results. This is to say that for a thermodynamic system all its interactions with anything outside it cannot be made to tend to zero togically, that is they cannot be made to vanish completely even in principle.
Theories of nature present neat pictures of reality, concerning themselves only with aspects of it and even within these limited aspects neglecting most of the features and that too with the help of ‘ideals’ and ‘limiting cases’. So reality is never actually that which the theory says but approximates to it and how good this approximation is determines how good a theory is. But the point is, reality must approximate to theory for theory to be acceptable. One way in which a theory can go wrong is that the real objects and phenomena do not approximate to the theoretical constructs therein, meaning that such constructs are not proper ‘ideals’, they do not represent the. ‘limiting case’ of the real situation or that they are wrong kind of ‘idealisations’. A thermodynamically isolated system is one such wrong kind of idealisation.
Thermodynamics has been presented axiomatically also. An axiomatic system is a mathematical structure based on certain axioms or postulates and a set of inference rules which allow one to derive new results starting with the axioms. The inference rules are taken from logic or mathematics and when a physical theory is axiomatised it is the axioms which charecterise the theory. For example when thermodynamics is axiomatised the axioms will be so formulated as to give shape to its laws and various other concepts like equilibrium, state of a system etc. The expression of laws also occurs in terms of axioms giving shape to certain basic concepts like energy, entropy etc. The set of axioms is a sufficient set which allows one to derive the otherwise known results of thermodynamics. One result of such axiomatic development is that a theory so developed cannot be falsified because the range of applicability of the theory is definitionally precisely that in which it is true. So if you apply it to problems traditionally supposed to be in its fold and find it inapplicable leading to the conclusion that the theory is false, your application will be called a misapplication and the theory exonerated.
This manner of defence of physical laws occured before axiomatisation also, albeit in loose way. For example Newton’s law of motion is as much a statement of motion of particles as it is a definition of force. The first law of thermodynamics is as much a statement about real life processes as it is a definition of energy. If and when such phenomena are found which controvert these laws, they will not be seen as falsifying the law but as a newly discovered constraint amounting to pruning and refining the concepts of force and energy. This tendecy of defense at all costs finally finds a neat expression in axiomatic formulations in the name of rigour. But I will take an. example of a very neat axiomatic theory to show how such theories get falsified too.
This is Euclidean geometry. Right from the time of Euclid, plane geometry was developed based on a set of postulates. The fifth postulate, called the parallel postulate, stated that given a line and a point outside it there exists exactly one line passing through the point and meeting the given line only at infinity. For centuries people failed to see it as self evident as other postulates were thought to be, and tried to show that it is contradictory to other postulates. Finally by showing that if in place of the parallel postulate, we have a postulate contrary to it the system remains consistent, its independence was shown. This later led to the development of non Euclidean geometries which in essence negate the parallel postulate. These non-Euclidean geometries were then used in Einstein's theory of gravitation or general relativity for which Euclidean theory was found inappropriate. The question is : Can Euclidean geometry be said to be a false description of reality? Does the fact that the straight line, which is the chief concept to which this geometry gives shape, does not have a counterpart in reality make the Euclidean geometry a false description of reality? Answer is: In a substantial sense, yes.
But now consider the apparently extraordinary fact that Euclidean and a class of non Euclidean geometries have been shown to be equivalent.16 That is to every theorem of one there corresponds a theorem of the other and vice versa. This means, in physical terms, that for all those phenomena and their theories for which non Euclidean geometry is an appropriate mathematical structure of description, Euclidean geometry should also be appropriate. Generally whatever is possible by the one should also be possible for the other. And yet it is sensible to maintain that Euclidean geometry is not usable where non Euclidean geometries are being used, otherwise there was no reason for them to develop also. This is a clear dilemma. Where lies the problem ? In fact, both the positions are right. What is involved is this. If you try to use Euclidean geometry where actually non-Euclidean geometries are used, you will have to radically change the meanings of words as primary as straight - line, angle and so on, with the net effect that the entire exercise will become meaningless. It is a humanly impossible exercise which has not been performed.
These considerations shed some light on how an axiomatic formulation of thermodynamics can also be falsified. If only such areas of inapplicabilities are considered which are marginal and do not drastically disturb the framework, basic concepts of energy and entropy can undergo refinement to adjust. But if areas of radical inapplicability are considered such as biological systems or processes of ingestion, then certainly thermodynamics faces a prospect of direct falsification. For in such a case if axiomatic theory is made to adjust by a redefinition of the meanings of. the concepts involved, it will become an uninteligible exercise.
It is quite probable that the veracity of theories of science is only a contextual concept., truth being related to the: needs of the dominant classes of an epoch. This is the message of energy as value and one need not scorn at an epoch relative, economic or class criterion of truth and therefore of the veracity of theories and laws of science.
Appendix: Shakthi: An Attempt at Developing A New Energy - Quality Marker17
Having thus seen that Thermodynamics is based on false conceptions and gives us such markers of energy - quality which guide the strategy of resource utilisation in a way which goes against the interests of people outside the modern sectors, let us now turn our attention to Seshadri’s attempts at formulation of a new. energy quality marker in which attempt is made to avoid these pitfalls and distortions. In fact it is not a search for a new energy quality marker but a search for a concept which may be quite like energy but different enough to incorporate many other ‘useful’ factors not accounted for under energy and laws of its conversion. As we shall see three such major factors suggested by him are ‘mass’, ‘information’, and ‘time’.
Seshadri states the practical problem as derived from the developing needs of the poor and the poor countries. Bio processes still constitute the explicit sources which fulfil their life-needs. In the face of modernisation constantly decreasing the resources of the world and affecting the ecosystems adversely the problem is stated as : ‘In a world of decreasing resources, how do we maintain a viable eco-system with a meaningful quality of life for all living beings? What are the descripters which will help us do this? The ones we have are useless’
(p. 13). This is a rather general statement of the problem. Various specific statements can be constructed which fall within its scope. For example, ‘Given a hectare of land what is the best mix of fuel, fodder and food that we should grow ?’ (p. 3). Another can be: what descripters can be used to specify an optimal human diet ? A related problem in agriculture relates to the need of a new concept of fertility.
Two important ways in which bio-processes differ from the processes involved in heat engines are (i) the transfers of mass are of crucial importance and (ii) rates of the processes are very different. This is only in nutshell because how these things happen is also very important. To show the importance of these factors Seshadri discusses a situation in which a heat engine and a tree are part of a system, called the green house (pp. 9-10). This is like a thought experiment. The heat engine burns wood from the tree, does work and rejects part of the energy as thermal energy lost for ever. But when we look at the mass of the off gases we see that carbon dioxide is being fixed by the tree. This contributes to the growth of the tree, wood from which is again used to burn in the heat engine.
If the engine is an ideal reversible engine the heat lost as unavailable work goes as radiated and convected sensible heat. In the case of a real engine there are many other losses due to friction, diffusion, mixing, turbulance and the sensible heat of off-gases. Butin both cases the material of transport is the off gas including carbon dioxide which is fixed by the tree, wood from which is used for combustion in the engine. So, the unavailability in this case in confined to the thermal part and not the mass part which is re-cyclable after some time. Also, strictly spereaking, thermal energy rejected is not all fost, for part of it is in the form of certain types of energy of the off gases, say vibrational and translational kinetic energy of the molecules of these gases. The mass of carbon dioxide is not seperatable from these kinetic energies and when the gas is used by the tree these thermal energy components are also used. A major problem in such a conceptualisation is that the rates of the processes in the engine are high compared to the rate of tree growth. But if the tree is replaced by an algal cell, the time taken to produce the biomass is shortened. The time factor can be reduced to a matter of hours if bacterial biomass is used for combustion. This clearly brings out the importance of both mass and time in energy conversion processes.
Some of these factors are brought in clear relief if we compare certain aspects of cycles of combustion and metabolism. Following is a slightly modified form of a table given by Seshadri. (p. 12).
It is pointed out that ‘self reference to previous history, reversibility and recursivity are a feature of life processes in addition to interacting cycles of many such processes’ (p. 13). In addition it is noted that the fundamental unit of life that must go into formulation of a general function ‘Shakthi’. Sheshadri has taken the example of specification of minimal or optimal human diet expressing the possibility of including the contributions of carbohydrates, proteins, lipids, fibre, ash, minerals and vitamins etc., in a single equation through the use of 'shakthi’ concept.
In fact development of such a Shakthi function may be expected to radically alter our concepts of fertility. The agricultural output may not be measured purely in terms of quintals per acre but in terms of the Shakthi output. This is more or less equivalent to answering the question posed earlier, namely, given a hectare of land what is the best mix of fuel, food and fodder that we should grow on it?
So although the examples of possible application of Shakthi are drawn primarily from the food realm, its relevance to the larger question of strategy of utilisation of resources is obvious. In fact, there follows a radical corollary so far as agriculture is concerned. It is this : It is well known that agriculture world over is economically unviable, thanks to modern industrial development and the energy-efficiency criterion. So, in the richer countries it is based on subsidy and in poorer countries on the exploitation of the farmer. In the modern world, in communist countries and in other places, this has been seen as an organisational problem. So, land reform and reorganisation of rural society have been attempted as solutions. Our considerations point out that there may be scientific technical components to the problem. Development of the concept of Shakthi is one such exercise which may provide alternative, more valuable and more real ways of getting round the scientific technical obstacles. That this will not make agriculture economically viable is obvious but what is important to note is that without it the political and economic changes, however radical, may not be able to change the given status of agriculture and so also the agriculturists,
Sunil Sahasrabudhe
Gandhian Institute of Studies,Varanasi
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