Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds,and other vertebrates. In mammals, testosterone is primarily secreted in the testicles of males and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid."Testosterone"
Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds,and other vertebrates. In mammals, testosterone is primarily secreted in the testicles of males and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid.
What Is "Prostate"
The prostate differs considerably among species anatomically, chemically, and physiologically.
What Is "Coulrophobia"
Coulrophobia is a fear of clowns. The term is of recent
origin, probably dating from the 1980s,and according to one analyst, "has been coined more on the Internet than in printed form because it does not appear in any previously published, psychiatric, unabridged, or abridged dictionary." However, the author later notes, "regardless of its less-than-verifiable etymology, coulrophobia exists in several lists".The condition is a specific phobia (DSM-IV Code 300.29).
Newton's 3rd Law
Newton's 3rd law may be formally stated:
"Forces always occur in pairs. If object A exerts a force F on object B,
then object B exerts an equal and opposite force –F on object A"
or
in slogan style:
"Every action has an equal and opposite reaction"
Note the important provision: two objects must be involved! There exists a whole set of situations where two equal and opposite forces act on the same object, canceling each other so that no acceleration (or even no motion) occurs. This is not an example of the third law, but ofequilibrium between forces. Some examples:
A heavy object stands on the floor, pulled down by the Earth with a force mg
Newton's Second Law
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The MKS System and the "newton"Consider free fall due to gravity. The force of gravity is proportional to mass m, so we can write where g is the acceleration of gravity, directed downwards. Yes, proportionality allows one to add on the right some constant multiplier, but we won't, because now we want to define some units of F. All quantitative formulas and units in physics depend on the units in which three basic quantities are measured--distance, mass. and time. Let us therefore choose from now on to measure distance in meters, mass in kilograms and time in seconds. That convention is known as the MKS system: as long as one's formulas contain only quantities derived by that system, they will be consistent and correct. But watch out... if by mistake you mix MKS units with grams or centimeters (or pounds and inches), and you may end up with some mighty strange results!
By that equation, a force of one newton acting on one kilogram of mass accelerates it by 1 m/sec2, so the force of gravity on one kilogram of mass is about 9.8 newtons. Earlier this was called "a force of one kilogram of weight, " a convenient unit for rough applications (1 kg = 9.8 newton), but not for accurate ones, because of the variation of g around the globe. Newton's Second LawWe now can express in numbers the dependence of acceleration on force and mass. Lord Kelvin, leading British scientist in Queen Victoria's era, was quoted as once saying
This expresses the earlier statement "accelerates in the direction of the force."Many textbooks write but equation (3) is the form in which it is usually used--F and m are the inputs, a is the result. The example below should make it clear. Example: the V-2 RocketThe V-2 military rocket, used by Germany in 1945, weighed about 12 tons (12,000 kg) loaded with fuel and 3 tons (3,000 kg) empty. Its rocket engine created a thrust of 240,000 N (newtons). Approximating g as 10m/s2, what was the acceleration of the V-2 (1) at launch (2) at burn-out, just before it ran out of fuel?Solution Let the upwards direction be positive, the downwards direction negative: using this convention, we can work with numbers rather than vectors. At launch, two forces act on the rocket: a thrust of +240,000 N, and the weight of the loaded rocket, mg = –120,000 N (if the thrust were less than 120,000 N, the rocket would never lift off!). The total upwards force is thereforeand the initial acceleration, by Newton's 2nd law, is The rocket thus starts rising with the same acceleration as a stone starts falling. As the fuel is used up, the mass m decreases but the force does not, so we expect a to grow larger. At burn-out, mg = –30,000 N and we have giving The fact that acceleration increases as fuel is burned up is particularly important in manned spaceflight, when the "payload" includes living astronauts. The body of an astronaut given an acceleration of 7 g will experience a force up to 8 times its weight (gravity still contributes!), creating excesive stress (3-4 g is probably the limit without special suits). It is hard to control the thrust of a rocket, but a rocket with several stages can drop the first stage before a gets too big, and continue with a smaller engine. Or else, as with the space shuttle and the original Atlas rocket, some rocket engines are shut off or dropped, while others continue operating. |
The Theory of Knowledge
"It is the customary fate of new truths to begin as heresies and to end as superstitions." (T. H. Huxley)The basic assumption underlying all science and rational thought in general is that the physical world exists, and that it is possible to understand the laws governing objective reality. The great majority of working scientists accept that the universe is governed by natural law, a fact pointed out by Philip Anderson:
"Indeed, it’s hard to imagine how science could exist if they didn’t. To believe in natural law is to believe that the universe is ultimately comprehensible—that the same forces that determine the destiny of a galaxy can also determine the fall of an apple here on earth; that the same atoms that refract the light passing through a diamond can also form the stuff of a living cell; that the same electrons, neutrons, and protons that emerged from the big bang can now give rise to the human brain, mind, and soul. To believe in natural law is to believe in the unity of nature at the deepest possible level." (26)
The same is true of the human race in general. Every new discovery of science and technique broadens and deepens our understanding, but by so doing, also poses new challenges. Every question answered immediately raises two more questions. Like a traveller who, with growing excitement, approaches the horizon, only to discover a new one, beckoning him from afar, the process of discovery unfolds with no end in sight. Scientists delve ever deeper into the mysteries of the subatomic world, in search of the "ultimate particle." But each time they reach the horizon with a triumphant cry, it stubbornly recedes into the distance.
It is the illusion of every epoch that it represents the ultimate peak of all human achievements and wisdom. The ancient Greeks thought that they had understood all the laws of the universe on the basis of Euclid’s geometry. Laplace thought the same in relation to Newton’s mechanics. In 1880, the chief of the Prussian patent office declared that everything that could ever be discovered had already been invented! Nowadays, scientists tend to be slightly more circumspect in their pronouncements. Even so, tacit assumptions are made that, for example, Einstein’s general relativity theory is absolutely true, and the principle of indeterminacy has a universal application.
The history of science shows how economical the human mind is. Very little is actually wasted in the process of collective learning. Even mistakes, when honestly analysed, can play a positive role. Only when thought becomes ossified into official dogma, which treats new ideas as heresy to be prohibited and punished, is the development of thought paralysed and even thrust back. The dismal history of science in the Middle Ages is sufficient proof of this. The search for the philosopher’s stone was based upon a mistaken hypothesis, yet the alchemists made important discoveries, and laid the basis for the development of modern chemistry. The big bang theory, with its search for a non-existent "beginning of time," has scarcely any better scientific credentials, yet, despite this, there is no doubt about the big advances which have been, and are being, made.
As Eric J. Lerner correctly observes: "Good data, competently obtained and analysed, is of scientific value even if the theory that inspired it is wrong. Other theorists will find uses for it that were little imagined when it was first gathered. Even in theoretical work, honest efforts to compare a theory to observation almost always prove useful regardless of the theory’s truth: a theoretician is bound to be upset if his idea is wrong, but time won’t have been wasted in ruling it out." (27)
The development of science proceeds through an infinite series of successive approximations. Each generation arrives at a series of fundamental generalisations about the workings of nature, which serve to explain certain observed phenomena. These are invariably considered to be absolute truths, valid for all time in "all possible worlds." On further examination, however, they are found to be not absolute, but relative. Exceptions are discovered, which contradict the established rules, and, in turn, demand explanation, and so on ad infinitum.
"The first discoveries were realisation that each change of scale brought new phenomena and new kinds of behaviour. For modern particle physicists, the process has never ended. Every new accelerator, with its increase in energy and speed, extends science’s field of view to tinier particles and briefer time scales, and every extension seems to bring new information." (28)
Should we therefore despair of ever achieving the whole truth? To pose the question in this way is not to understand the nature of truth and human knowledge. Thus Kant thought that the human mind could only ever know appearances. Behind the world of appearances lay the Thing-in-Itself, which we can never know. To this Hegel replied that to know the properties of a thing is to know the thing itself. There is no absolute barrier between appearance and essence. We start with the reality which presents itself to us in sense-perception, but we do not stop here. Using our intellect, we penetrate ever deeper into the mysteries of matter, passing beyond appearance to essence; from the particular to the universal; from the secondary to the fundamental; from the facts to the law.
To use the terminology which Hegel used to answer Kant, the whole history of science and of human thought in general is the process of changing the Thing-in-Itself into a Thing-for-Us. In other words, what "cannot be known" at a given stage of the development of science is eventually explored and explained. Every barrier placed in the way of thought is broken down. But in solving one problem, we immediately come up against new ones which must be solved, new challenges to be overcome. And this process will never come to an end, because the properties of the material universe are indeed infinite.
"To pursue our analogy further," writes David Bohm, "we may say that with regard to the totality of natural laws we never have enough views and cross-sections to give us a complete understanding of this totality. But as science progresses, and new theories are developed, we obtain more and more views from different sides, views that are more comprehensive, views that are more detailed, etc. Each particular theory or explanation of a given set of phenomena will then have a limited domain of validity and will be adequate only in a limited context and under limited conditions. This means that any theory extrapolated to an arbitrary context and to arbitrary conditions will (like the partial views of our object) lead to erroneous predictions. The finding of such errors is one of the most important means of making progress in science.
"A new theory, to which the discovery of such errors will eventually give rise, does not, however invalidate the older theories. Rather, by permitting the treatment of a broader domain in which they are inadequate and, in so doing, it helps define the conditions under which they are valid (e.g. as the theory of relativity corrected Newton’s laws of motion, and thus helped to define the conditions of validity of Newton’s laws as those in which the velocity is small compared with that of light). Thus, we do not expect that any causal relationships will represent absolute truths; for to do this, they will have to apply without approximation, and unconditionally. Rather, then, we see that the mode of progress of science is, and has been, through a series of progressively more fundamental, more extensive, and more accurate conceptions of the laws of nature, each of which contributes to the definition of the conditions of validity of the older conceptions (just as broader and more detailed views of our object contribute to defining the limitations of any particular view or set of views)."
(29) In his book The Structure of Scientific Revolution, Professor Thomas Kuhn pictures the history of science as periodic theoretical revolutions, punctuating long periods of merely quantitative change, mainly devoted to filling in details. In such "normal" periods, science operates within a given set of theories which he calls paradigms, which are unquestioned assumptions about what the world is like. Initially, the existing paradigm stimulates the development of science, providing a coherent framework for investigation. Without such an agreed framework, scientists would be forever arguing about the fundamentals. Science, no more than society, cannot live in a permanent state of revolutionary upheaval. For this very reason, revolutions are relatively rare events, both in society and science.
For a time, science is able to advance along these well-trodden paths, piling up results. But in the meanwhile, what were originally daring new hypotheses become transformed into rigid orthodoxies. If an experiment produces results that conflict with the existing theories, scientists may suppress them, because they are subversive to the existing order. Only when the anomalies build up to the point where they cannot be ignored is the ground prepared for a new scientific revolution, which overthrows the dominant theories and opens up a new period of "normal" scientific development, on a higher level.
While it is undoubtedly over-simplified, this picture of the development of science, as a broad generalisation, can be accepted as true. In his book Ludwig Feuerbach, Engels explains the dialectical nature of the development of human thought, as exemplified both in the history of science and philosophy:
"Truth, the cognition of which is the business of philosophy, was in the hands of Hegel no longer an aggregate of finished dogmatic statements, which, once discovered, had merely to be learned by heart. Truth lay now in the process of cognition itself, in the long historical development of science, which mounts from lower to ever higher levels of knowledge without ever reaching, by discovering so-called absolute truth, a point at which it can proceed no further, where it would have nothing more to do than to fold its hands and gaze with wonder at the absolute truth to which it had attained."
And again:
"For it [dialectical philosophy] nothing is final, absolute, sacred. It reveals the transitory character of everything and in everything; nothing can endure before it except the uninterrupted process of becoming and of passing away, of endless ascendancy from the lower to the higher. And dialectical philosophy itself is nothing more than the mere reflection of this process in the thinking brain. It has, of course, also a conservative side: it recognises that definite stages of knowledge and society are justified for their time and circumstances; but only so far. The conservatism of this mode of outlook is relative; its revolutionary character is absolute—the only absolute dialectical philosophy admits." (30)
What Is the Scientific Method?
In the 3rd century B.C. the Greek scholar Eratosthenes read that a vertical stick, positioned in a place called Syrene, cast no shadow at midday. He then observed that in his own city, Alexandria, a vertical stick did cast a shadow. From these observations of real physical phenomena, he deduced that the earth was round. He then sent a slave to Syrene to measure the distance from Alexandria. Then, using simple geometry, he calculated the circumference of the earth. This is the real method of science in action. It is a mixture of observation, hypothesis and mathematical reasoning. Eratosthenes began with observation (both his own and that of others). Then, on the basis of this, he drew a general conclusion, the hypothesis that the earth is curved. He then made use of mathematics to give a precise form to his theory.
The brilliant achievements of Alexandrine science were eclipsed by the rise of Christianity in the Dark Ages. For centuries, the development of science was paralysed by the spiritual dictatorship of the Church. Only by freeing itself of the influence of religion did science manage to develop. Yet by a strange quirk of history, at the end of the 20th century determined attempts are being made to drag science backwards. All kinds of quasi-religious and mystical ideas are floating in the air. This strange phenomenon is closely related to two things. Firstly, the division of labour has been carried to such extremes that it has begun to cause serious harm. Narrow specialisation, reductionism, and an almost complete divorce between the theoretical and experimental side of physics has had the most negative consequences.
Secondly, there has been no adequate philosophy which could help to point science in the right direction. The philosophy of science is in a mess. This is not surprising, because the prevailing "philosophy of science"—or rather the philosophical sect of logical positivism which set itself up in this capacity—is least of all able to help science out of its difficulties. On the contrary, it has made matters worse. In recent decades, we have seen a growing tendency in theoretical physics to approach the phenomena of the natural world from an excessively abstract and mathematical standpoint. This is clearly the case in the arbitrary attempt to reconstruct an alleged beginning of the universe. As Anderson pointed out in an article written in 1972:
"The ability to reduce everything to simple fundamental laws does not imply the ability to start from those laws and reconstruct the universe. In fact, the more the elementary particles physicists tell us about the nature of the fundamental laws, the less relevance they seem to have to the very real problems of the rest of science, much less society." (31)
In recent decades the prejudice has become deeply rooted that "pure" science, especially theoretical physics is the product of abstract thought and mathematical deduction alone. As Eric Lerner explains, Einstein was partly responsible for this tendency. Unlike earlier theories, such as Maxwell’s laws of electromagnetism, or Newton’s laws of gravity, which were firmly based on experiment, and soon confirmed by hundreds of thousands of independent observations, Einstein’s theories were initially confirmed on the basis of only two—the deflection of starlight by the sun’s gravitational field and a slight deviation in the orbit of Mercury. The fact that relativity theory was subsequently shown to be correct has led others, possibly not quite up to Einstein’s level of genius, to assume that this is the way to proceed. Why bother with time-consuming experiments and tedious observations? Indeed, why depend upon the evidence of the senses at all, when we can get straight to the truth through the method of pure deduction?
We must remind ourselves that the great breakthrough in science came in the Renaissance, when it separated itself from religion, and began to base itself upon observation and experiment, setting out from the real material world, and always returning to it. In the 20th century, however, there has been a partial regression to idealism, both Platonism and still worse, to the subjective idealism of Berkeley and Hume. For all his unquestioned genius, Einstein was unable to free himself from this trend, although he frequently recoiled against the consequences that flowed from it. It is to his credit, for example, that he conducted a stubborn rearguard action against the subjective idealist interpretation of quantum mechanics put forward by Heisenberg.
Like many scientists, Einstein did not feel at home with philosophy, and honestly confessed that great scientists tend to make poor philosophers of science. Nevertheless, he himself made a number of pronunciations of a philosophical or semi-philosophical character, which, given his colossal prestige, were bound to be taken seriously by many scientists—with some very unfortunate results. In 1934, for example, he wrote:
"The theory of relativity is a fine example of the fundamental character of the modern development of theoretical science. The hypotheses with which it starts are becoming steadily more abstract and remote from experience. The theoretical scientist is compelled in an increasing degree to be guided by purely mathematical, formal considerations in his search for a theory, because the physical experience of the experimenter cannot lift him into the regions of highest abstraction. The predominantly inductive methods appropriate to the youth of science are giving place to tentative deduction." (32)
In point of fact, it is not true that Einstein arrived at his theories through a process of pure reasoning and deduction. As he himself states in his Essays in Science, his theory of special relativity was derived from Maxwell’s work on electricity and magnetism, which, in turn, was based on the work of Faraday, with its solid experimental foundations. Only after 1915, when he turned to cosmology did Einstein turn to the method of abstract deduction to obtain his results. Here he departed from the established method by taking as his fundamental hypothesis an assumption which was contradicted by observation: the notion that the universe as a whole is homogeneous (evenly spread throughout space).
Setting out from this proposition, Einstein used his general theory of relativity to prove that space is finite. According to this view, the greater the mass of a given density, the more it "curves space." A sufficiently large mass will lead to a situation where space curves round on itself altogether, thus producing a "closed universe." This marked, in effect, a regression to the mediaeval world outlook of a finite universe, previously rejected as unscientific. However, even in 1915, there was sufficient evidence to show that the universe was not homogeneous. The theory collided with the facts established by observation. It is no coincidence that Einstein’s search for a unified theory of gravitation and electromagnetism during his last thirty years ended in failure, as he himself admitted.
Limits of Empiricism
Real philosophy ended with Hegel. Since then, we have seen only a tendency to repeat old ideas, occasionally a filling out of this or that detail, but no real breakthrough, no great new idea. This is hardly surprising. The unprecedented advances of science over the past hundred years makes philosophy in the old sense of the word redundant. There is very little point in speculating about the nature of the universe, when we are in a position to uncover its secrets with the aid of ever more powerful telescopes, space-probes, computers and particle accelerators. Just as the debate about the nature of the solar system was decided by Galileo’s telescope, so the advances in technique will settle the question of the history of the universe, only to pose new questions for future generations to solve.
"As soon as each separate science is required to clarify its position in the great totality of things and of our knowledge of things, a special science dealing with this totality is superfluous," wrote Engels. "All that remains in an independent state from all earlier philosophy is the science of thought and its laws—formal logic and dialectics. Everything else merges into the positive science of nature and history." (33)
Yet philosophy still has a role to play, in the only two areas left to it—formal logic and dialectics. Science, as we have seen, is not merely concerned with accumulating facts. It still requires the active intervention of thought, which alone can discover the inner meaning of the facts, their lawfulness. It is still necessary to make hypotheses, which can guide our investigations along the most fruitful channels, to grasp the real interrelations between apparently unrelated phenomena, to derive order from chaos. This requires training and a thorough knowledge of the history of both science and philosophy. As the American philosopher George Santayana put it, "He who does not learn from history is doomed to repeat it." One of the most pernicious consequences of the influence of logical positivism in 20th century science is that all the great schools of the past were treated like a dead dog. Now we see where this attitude leads us. Those who haughtily dismissed "metaphysics" have been punished for their pride. At no time in the history of science has mysticism been so rampant as now.
The purely empirical school of thought inevitably leads to this, as Engels pointed out long ago:
"Exclusive empiricism, which at most allows itself thinking in the form of mathematical calculation, imagines that it operates only with undeniable facts. In reality, however, it operates predominantly with traditional notions, with the largely obsolete products of thought of its predecessors, and such are positive and negative electricity, the electric force of separation, the contact theory. These serve it as the foundation of endless mathematical calculations in which, owing to the strictness of the mathematical formulation, the hypothetical nature of the premises gets comfortably forgotten. This kind of empiricism is as credulous towards the results of the thought of its predecessors as it is sceptical in its attitude to the results of contemporary thought. For it even the experimentally established facts have gradually become inseparable from their traditional interpretations…They have to resort to all kinds of subterfuges and untenable expedients, to the glossing over of irreconcilable contradictions, and thus finally land themselves into a medley of contradictions from which they have no escape." (34)
It is impossible for scientists to remain aloof from society, on the grounds that they are purely impartial. None of us live in a vacuum. As the American geneticist Theodosius Dobzhansky says:
"Scientists often have a naïve faith that if only they could discover enough facts about a problem, these facts would somehow arrange themselves in a compelling and true solution. The relation between scientific discovery and popular belief is not, however, a one-way street. Marxists are more right than wrong when they argue that the problems scientists take up, the way they go about solving them, and even the solutions they are inclined to accept, are conditioned by the intellectual, social, and economic environments in which they live and work." (35)
It is sometimes asserted that Marx and Engels considered the dialectic to be some kind of Absolute—the last word in human knowledge. Such a notion is a self-evident contradiction. The Marxian dialectic differs from the Hegelian in two fundamental ways. Firstly, it is a materialist philosophy, and therefore derives its categories from the world of physical reality. Nature is infinite, not closed. Likewise, truth itself is endless and cannot be summed up in a single all-embracing system. The negation of the negation, as Engels explains, is a kind of spiral of development—an open-ended system, not a closed circle. That is the second fundamental difference with the Hegelian philosophy, which ultimately contradicted itself by attempting to express the dialectic as a closed and absolute System.
Marx and Engels worked out the outline of a new dialectical method, the usefulness of which was brilliantly shown in the three volumes of Capital. But the enormous advances of 20th century science provides ample material with which to fill out, develop and extend the content of dialectics. The further evolution of chaos and complexity theory can provide the basis for such a development, which would be of immense benefit to both the natural and social sciences. We cannot therefore say that dialectical materialism will not in the future be overtaken by some new and more satisfactory mode of thinking. But we can certainly say that up to the present time, it is the most advanced, comprehensive and flexible method of scientific analysis available. Let Engels speak for himself on this subject:
"Further, if no philosophy as such is needed any longer, then no system, not even a natural system of philosophy, is needed any longer either. The recognition of the fact that all the processes of nature are systematically interconnected drives science on to prove this systematic interconnection throughout, both in general and in detail. But an adequate, exhaustive scientific exposition of this interconnection, the formation of an exact mental image of the world system in which we live, remains impossible for us, as it does for all times. If at any epoch in the development of mankind such a final, definitive system of the interconnections within the world—physical as well as mental and historical—were constructed, this would mean that the realm of human knowledge had reached its limit, and that further historical development would be cut short from the moment when society had been brought into accord with that system—which would be an absurdity, pure nonsense.
"Mankind therefore finds itself faced with a contradiction: on the one hand, it has to gain an exhaustive knowledge of the world system in all its interconnections, and on the other hand, this task can never be completely fulfilled because of the nature both of men and of the world system. But this contradiction not only lies in the nature of the two factors—the world and man—it is also the main lever of all intellectual advance, and constantly finds its solution, day by day, in the endless progressive development of humanity, just as for example mathematical problems find their solution in an infinite series or continued fractions. Actually, each mental image of the world system is and remains limited, objectively by the historical situation and subjectively by its author’s physical and mental constitution." (36)
Prejudice Against Dialectics
Modern science furnishes an abundance of material which completely confirms Engels’ assertion that "in the last analysis, nature works dialectically." The discoveries of science in the hundred years since Engels died completely confirms this view.
"When we reflect on Nature, or the history of mankind, or our own intellectual activity," Engels wrote, "the first picture presented to us is of an endless maze of relations and interactions, in which nothing remains what, where and as it was, but everything moves, changes, comes into being and passes out of existence. This primitive, naïve, yet intrinsically correct conception of the world was that of ancient Greek philosophy, and was first clearly formulated by Heraclitus: everything is and also is not, for everything is in flux, is constantly changing, constantly coming into being and passing away." (37)
Let us compare this to another quotation from Hoffmann: "In the world of quantum, particles are incessantly appearing and disappearing. What we would think of as empty space is a teeming, fluctuating nothingness, with photons appearing from nowhere and vanishing almost as soon as they were born, with electrons frothing up for brief moments from the monstrous ocean to create evanescent electron-proton pairs and sundry other particles adding to the confusion." (38)
The rise of chaos and complexity theory indicates a welcome reaction against the stultifying reductionism of the past. Yet very little attention has been paid to the pioneering work of Hegel, Marx and Engels. This astonishing fact is largely to be explained by the widespread prejudice against dialectics, partly as a reaction against the mystical way that dialectics was presented by the idealist school after Hegel’s death, but mainly because of its connection with Marxism. Hegel’s dialectics have been described as the "algebra of revolution." If the law of quantity and quality is accepted as valid for chemistry and physics, the next step would be to apply it to existing society, with most unfortunate consequences for the defenders of the status quo.
The scientific writings of Marx and Engels cannot be separated from their revolutionary theory of history in general (historical materialism), and their analysis of the contradictions of capitalism. There are evidently not very popular with those who currently possess a monopoly of economic and political power, and who control, not only the newspapers and television companies, but also hold in their hands the purse-strings which determine the fate of universities, research-projects, and academic careers. Is it surprising that dialectical materialism is a taboo subject, which is systematically passed over in silence, except when it is denounced as unscientific mumbo-jumbo, by people who have clearly never read a single line of Marx or Engels? True, a small number of brave souls have raised the question of the contribution of Marxism to the philosophy of science, but even then, such mentions are frequently hedged round with all kinds of qualifications, aiming to show that dialectics may be valid for a given field of science, but cannot be accepted as a general proposition.
Nowadays, the idea of change, of evolution, has deeply penetrated the popular consciousness. But evolution is generally understood as a slow, gradual, uninterrupted process. As Trotsky put it, "Hegel’s logic is the logic of evolution. Only one must not forget that the concept of ‘evolution’ itself has been completely corrupted and emasculated by university professors and liberal writers to mean peaceful ‘progress.’"
In politics, this common prejudice finds its expression in the theory of reformist gradualism, where today is better than yesterday and tomorrow will be better than today. Sadly, human history in general, and the history of the 20th century in particular, provides precious little comfort for the supporters of this tranquillising view of the social process. History knows long periods of gradual change but this is by no means a continuous and smooth process. It is interrupted by all kinds of explosions and catastrophes: wars, economic crises, revolutions and counter-revolutions. To deny this is to deny what everyone knows to be true. So how do we regard these phenomena? As sudden, inexplicable outbreaks of collective madness? As accidental "deviations" from the gradualist "norm"? Or, on the contrary, are they to be seen as an integral part of the process of social development—not accidents but the necessary outcome of tensions and stresses that build up gradually and unseen within society and which, sooner or later, must force their way to the surface, just as the pressures that accumulate along a fault-line in the earth’s crust result in an earthquake?
Any attempt to banish contradiction from nature, to smooth out its rough edges, to subject it to the neat rules of formal logic, as the gardeners at Versailles subjected rude nature to the rules of classical geometry, is doomed to fail. Such efforts may well have a soothing effect upon the nerves, but will prove to be utterly useless to arrive at an understanding of the real world. And what is true for inanimate and animate nature is also true for the history of human society itself, despite the stubborn attempts to demonstrate the contrary. The history of society reveals the self-same tendencies—the inner contradictions that impel development; the rise and fall of different socioeconomic systems; the long periods of gradual "evolutionary" change, punctuated by sudden upheavals, wars and revolutions, which stand at the crossroads of every great historical development. Are such striking phenomena merely to be shrugged off as accidents, temporary and unfortunate deviations from the alleged evolutionary "norm"? Or irrefutable proof of the stupidity or inherent wickedness of human beings?
If this is the case, then all attempts to arrive at a rational understanding of human development must be abandoned. We are compelled to echo the opinion of Edward Gibbon, author of The Decline and Fall of the Roman Empire who described history as "little more than the register of the crimes, follies, and misfortunes of mankind." But if, as we firmly believe, human history proceeds according to the same dialectical laws that we observe throughout nature (and why should the human race claim the unlikely "privilege" of being entirely exempt from objective laws of development?) then the pattern of human history for the first time begins to make sense. It can be explained. It can even—within certain limits—be predicted, although predictions of complex phenomena are not as straightforward as ones involving simple linear processes. This applies just as much to predicting an earthquake or the weather as it does to anticipating the movement of society. No one can say for certain when the city of Los Angeles will fall victim to a catastrophic earthquake, but one can predict with absolute certainty that such a thing will happen.
Despite the most strenuous efforts to deny the validity of dialectics, the latter always takes its revenge on its most hardened detractors. The conservative geological community has been compelled to accept continental drift, the birth and death of continents, which they once laughed out of court. Biologists have been compelled to accept that the old idea of evolution as a gradual, uninterrupted process of adaptation is one-sided and false; that evolution takes place through catastrophic qualitative leaps, in which death (extinction) becomes the precondition for birth (new species).
At every turn, the wealth of material furnished by the natural sciences compel scientists to adopt dialectical conclusions. However, they soon become uncomfortably aware of the potentially "subversive" implications of such ideas. It is at this point that they hasten to resort to all kinds of embarrassed disclaimers and subterfuges in order to cover up their tracks. The usual get-out is to protest ignorance concerning philosophy in general. Like Oscar Wilde’s "love that dare not speak its name," these authors who wax eloquent about everything under the sun, find themselves utterly unable to pronounce the words dialectical materialism. At best, they insist, in effect, that dialectical materialism is valid for their own narrow speciality but has no application to the broader field of science or (perish the thought!) to society at large.
It is surprising that even those proponents of the theory of chaos who come quite close to a dialectical position display a complete lack of knowledge about Marxism. Thus, Ian Stewart and Tim Poston could write in Analog (November 1981) the following lines:
"So the ‘inexorable laws of physics’ on which—for instance—Marx tried to model his laws of history, were never really there. If Newton could not predict the behaviour of three balls, could Marx predict that of three people? Any regularity in the behaviour of large assemblies of particles or people must be statistical, and that has quite a different philosophical taste." (39)
This is completely off the mark. Marx did not base his model of history on the laws of physics at all. The laws of social development must be derived from a painstaking study of society itself. Marx and Engels devoted the whole of their lives to such a study, based upon a colossal amount of carefully collected empirical data, as even the most superficial examination of the three volumes of Capital alone will reveal. Incidentally, both Marx and Engels were highly critical of mechanical determinism in general and Newton in particular. The attempt to establish some parallel between Marx’s method and that of Newton and Laplace is without the slightest foundation.
The closer chaos and complexity theory moves to an examination of existing society, the greater is the potential for arriving at an understanding of the contradictions of capitalism:
"But in the United States, the ideal is maximum individual freedom—or, as (Brian) Arthur puts it, ‘letting everybody be their own John Wayne and run around with guns.’ However much that ideal is compromised in practice, it still holds mythic power.
"But increasing returns cut to the heart of that myth. If small chance events can lock you into any of several possible outcomes, then the outcome that’s actually selected may not be the best. And that means that maximum individual freedom—and the free market—might not produce the best of all possible worlds. So by advocating increasing returns, Arthur was innocently treading into a minefield." (Brian Arthur is an economist and one of the theoreticians of complexity.) (40)
Stephen Jay Gould, who has made an important contribution to current evolutionary theory, is one of the few Western scientists who has openly recognised the parallels between his theory of "punctuated equilibria" and dialectical materialism. In his book, The Panda’s Thumb, he says the following:
"If gradualism is more a product of Western thought than a fact of nature, then we should consider alternative philosophies of change to enlarge our realm of constraining prejudices. In the Soviet Union, for example, scientists are trained with a very different philosophy of change—the so-called dialectical laws, reformulated by Engels from Hegel’s philosophy. The dialectical laws are explicitly punctuational. They speak, for example, of the ‘transformation of quantity into quality.’ This may sound like mumbo jumbo, but it suggests that change occurs in large leaps following a slow accumulation of stresses that a system resists until it reaches the breaking point. Heat water and it eventually boils. Oppress the workers more and more and bring on the revolution. Eldredge and I were fascinated to learn that many Russian palaeontologists support a model similar to our punctuated equilibria."
Palaeontology and anthropology are, after all, only separated by a very thin wall from the historical and social sciences, which have potentially dangerous political implications for the defenders of the status quo. As Engels pointed out, the nearer one gets to the social sciences, the less objective and the more reactionary they become. It is therefore encouraging that Stephen Gould has come quite close to a dialectical point of view, despite his obvious caution:
"Nonetheless, I will confess to a personal belief that a punctuational view may prove to map tempos of biological and geologic change more accurately and more often than any of its competitors—if only because complex systems in a steady state are both common and highly resistant to change." (41)
In the last century, Marx ironically pointed out that most of the natural scientists were "shamefaced materialists." In the last half of the 20th century, we have a still greater paradox. Scientists who have never read a word of Marx or Hegel, have independently arrived at many of the ideas of dialectical materialism. We are firmly convinced that the future development of science will confirm the importance of the dialectical method, and that those who pioneered it will finally obtain the recognition which has been denied them.
Stalinist Caricature
A serious obstacle in the path of many who approached the ideas of Marxism in the past was the caricature presented by Stalinism. This played a contradictory role. On the one hand, the tremendous successes of the nationalised planned economy in the Soviet Union powerfully attracted many workers and intellectuals in the West. Prominent scientists such as the celebrated biologist J. B. S. Haldane in Britain were drawn to Marxism, and began to apply it to their own fields with promising results. A large number of works appeared which attempted to explain the latest discoveries of science in a comprehensible language. The results were uneven, but this literature was infinitely preferable to the mystifying stuff produced for popular consumption today.
There is no doubt that the unprecedented advances of culture, education and science in Russia served as a point of reference not just for the international labour movement, but for the best of the intellectuals and scientists in the West. These achievements showed the potential of a nationalised planned economy, despite all the monstrous bureaucratic distortions which ultimately undermined it. They stand in stark contrast to the present situation. The fall of the Soviet Union, and the attempt to move in the direction of a "market economy" has produced a frightful collapse of the productive forces and culture. Overnight, a colossal ideological counter-offensive has been launched on a world scale against the idea of a planned economy, Marxism and socialism in general. The enemies of socialism have taken advantage of the crimes of Stalinism to attempt to blacken the name of Marxism. They aim to convince people that revolution does not pay and that, consequently, it is better to put up with the rule of the big banks and monopolies, accept mass unemployment and falling living standards, because, they say there is "no alternative."
In reality, what failed in Russia was not socialism, but a bureaucratic caricature of socialism. A totalitarian and bureaucratic system is incompatible with a regime of nationalised planned economy which, as Leon Trotsky explained in 1936, needs democracy as the human body needs oxygen. Without the active and conscious participation of the population at all levels, without complete freedom of criticism, discussion and debate, it would inevitably lead to a nightmare of bureaucracy, corruption, red tape, bungling and mismanagement, which would undermine the basis of the planned economy in the end. This is precisely what happened in the former Soviet Union, as predicted by Marxists decades ago.
The totalitarian regime of Stalinism, with its inevitable companions, corruption, conformism and toadyism, had its most negative effects in the fields of science and the arts. Despite the enormous impulse given to education and culture by the October revolution and the nationalised planned economy that issued from it, the free development of science was held back by the suffocating bureaucratic regime. More than any other section of society, science and the arts need to develop in an atmosphere of intellectual freedom, freedom to think, to speak, to explore, to make mistakes. In the absence of such conditions, creative thought will wither and die. Thus the USSR, with more scientists than America and Japan together (and they were good scientists), was unable to get the same results as in the West, and gradually fell behind in a whole series of fields.
One of the things which created all kinds of misconceptions about Marxism was the way that it was presented by the Stalinists. The ruling elite in Russia could not tolerate freedom of thought and criticism in any sphere. In the hands of the bureaucracy, Marxist philosophy ("diamat" as they called it) was twisted into a sterile dogma, or a variety of sophism used to justify all the twists and turns of the leadership. According to Lefebvre, at one point things got so bad that the Soviet army high command insisted that lessons on formal logic be put back on the curriculum of military academies because of the shameful confusion caused by the teachers of so-called "diamat." At least lessons in logic would teach the cadets the ABCs of reasoning. This little incident is enough to expose the caricature nature of the "Marxism" of the Stalinists.
Under Stalin, scientists were forced to accept without question this rigid and lifeless caricature, as well as a number of false theories with no scientific basis which happened to suit the bureaucracy, such as Lysenko’s "theory" of genetics. This discredited the idea of dialectical materialism in the scientific community to a certain extent, and prevented a fruitful and creative application of the method of dialectics to different fields of science, which would have made possible serious advances both in the sciences themselves and in the further elaboration of the philosophical ideas which Marx and Engels explained in outline, but left to future generations to develop and fill out in detail.
It is a condemnation of the Stalinist regime that, for more than six decades, with all the resources of the Soviet state at its disposal, the bureaucracy was unable to introduce a single original idea into the theoretical arsenal of Marxism. In spite of the tremendous advantages of the nationalised planned economy, which created a powerful industry and technology. They proved incapable of adding anything new to the discoveries of Karl Marx, working alone in the library of the British Museum.
Despite everything, the benefits of a planned economy permitted outstanding progress in many fields, a fact which the present avalanche of propaganda would like to conceal. Moreover, where scientists did apply the dialectical method to different fields, interesting results were obtained. This is shown precisely by chaos theory, one area in which Soviet scientists, undoubtedly influenced by dialectical materialism, were in advance of the West by at least two decades. It is not generally realised that the original research into chaos theory was done in the Soviet Union, and this gave an impulse to those Western scientists who were independently coming to the same conclusions, and whose ideas in turn stimulated the further development of Soviet research into chaos, as Gleick admits:
"The blossoming of chaos in the United States and Europe has inspired a huge body of parallel work in the Soviet Union; on the other hand, it also inspired considerable bewilderment, because much of the new science was not so new in Moscow. Soviet mathematicians and physicists had strong tradition in chaos research, dating back to the work of A. N. Kolmogorov in the fifties. Furthermore, they had a tradition of working together that had survived the divergence of mathematics and physics elsewhere." (42)
Who Is "Nikola Tesla"
Nikola Tesla 1856 – 1943
“The scientists of today think deeply instead of clearly. One must be sane to think clearly, but one can think deeply and be quite insane.”
Who Is "Albert Einstein"
Albert Einstein 1879 – 1955
“A man should look for what is, and not for what he thinks should be.”
Who Is "Isaac Newton"
1.Isaac Newton 1643 – 1727
“To myself I am only a child playing on the beach, while vast oceans of truth lie undiscovered before me.”
Newton was an English physicist, mathematician, astronomer, natural philosopher, alchemist, theologian and one of the most influential men in human history. His Philosophiæ Naturalis Principia
Mathematica, published in 1687, is considered to be the most influential book in the history of science. In this work, Newton described universal gravitation and the three laws of motion, laying the groundwork for classical mechanics, which dominated the scientific view of the physical universe for the next three centuries and is the basis for modern engineering. Newton showed that the motions of objects on Earth and of celestial bodies are governed by the same set of natural laws by demonstrating the consistency between Kepler’s laws of planetary motion and his theory of gravitation, thus removing the last doubts about heliocentrism and advancing the scientific revolution. In mechanics, Newton enunciated the principles of conservation of momentum and angular momentum. In optics, he built the first “practical” reflecting telescope and developed a theory of color based on the observation that a prism decomposes white light into a visible spectrum. He also formulated an empirical law of cooling and studied the speed of sound. In mathematics, Newton shares the credit with Gottfried Leibniz for the development of the differential and integral calculus. He also demonstrated the generalized binomial theorem, developed the so-called “Newton’s method” for approximating the zeroes of a function, and contributed to the study of power series. Newton’s stature among scientists remains at the very top rank, as demonstrated by a 2005 survey of scientists in Britain’s Royal Society asking who had the greater effect on the history of science, Newton was deemed much more influential than Albert Einstein.
What is DTH?
What is DTH?
DTH stands for Direct-To-Home television. DTH is defined as the reception of satellite programmes with a personal dish in an individual home.DTH does away with the need for the local cable operator and puts the broadcaster directly in touch with the consumer. Only cable operators can receive satellite programmes and they then distribute them to individual homes.
How does DTH work?
A DTH network consists of a broadcasting centre, satellites, encoders, multiplexers, modulators and DTH receivers.
A DTH service provider has to lease Ku-band transponders from the satellite. The encoder converts the audio, video and data signals into the digital format and the multiplexer mixes these signals. At the user end, there will be a small dish antenna and set-top boxes to decode and view numerous channels. On the user's end, receiving dishes can be as small as 45 cm in diametre.
DTH is an encrypted transmission that travels to the consumer directly through a satellite. DTH transmission is received directly by the consumer at his end through the small dish antenna. A set-top box, unlike the regular cable connection, decodes the encrypted transmission.
How does DTH really differ from cable TV?
The way DTH reaches a consumer's home is different from the way cable TV does. In DTH, TV channels would be transmitted from the satellite to a small dish antenna mounted on the window or rooftop of the subscriber's home. So the broadcaster directly connects to the user. The middlemen like local cable operators are not there in the picture.
DTH can also reach the remotest of areas since it does away with the intermediate step of a cable operator and the wires (cables) that come from the cable operator to your house. As we explained above, in DTH signals directly come from the satellite to your DTH dish.
Also, with DTH, a user can scan nearly 700 channels!
Does one need to put two dish antennae and pay double subscription per month if one has two TVs [ Get Quote ]?
For multiple connections in the same premises, one can use the same connection. However, every television set will need to have an individual STB.
Also, DTH is a national service and the STBs enable a viewer to change service providers without changing the STB, even if one moves from one city to another.
Can a CAS set-top box be used for DTH?
No, these are different set-top boxes.
Why is DTH is being discussed now?
Doordarshan plans to launch its DTH telecast from April 1. The government has said it will provide 10,000 dishes free across eight states for increased community viewing of the DTH service. The government is estimated to be investing over Rs 300 crore (Rs 3 billion) in this DTH venture.
There are four serious contenders for DTH services in India: Doordarshan, Star, Zee, and Data Access.
Is DTH superior to cable TV?
Yes. DTH offers better quality picture than cable TV. This is because cable TV in India is analog. Despite digital transmission and reception, the cable transmission is still analog. DTH offers stereophonic sound effects. It can also reach remote areas where terrestrial transmission and cable TV have failed to penetrate. Apart from enhanced picture quality, DTH has also allows for interactive TV services such as movie-on-demand, Internet access, video conferencing and e-mail. But the thing that DTH has going for it is that the powerful broadcasting companies like Star, Zee, etc are pushing for it.
So why are broadcasters pushing for DTH?
In DTH, the payments will be made directly by the subscriber to the satellite company offering the service.
A big problem that broadcasters face in India is the issue of under-reporting of subscribers by cable operators.
Consider the cable operators pyramid. Right at the top is the broadcaster. Next comes the Multi Service Cable Operator (MSOs) like Siticable, InCable, etc. Below them are the Access Cable Operators (ACOs) or your local cable guy who actually lays the wires to your house.
The local cable operators or the ACOs then allegedly under-report the number of subscribers they have bagged because they have to pay the MSOs something like Rs 30-45 per household. Showing a lesser number of households benefits ACOs.
With no way to actually cross check, the MSOs and the broadcasters lose a lot. Broadcasters do not earn much in subscription fees and are mostly dependent on advertisement revenue to cover their costs, which is not sustainable and does not offer high growth in revenues for broadcasters.
The way out of this is to use a set-top box so that it will be clear how many households are actually using cable or going for DTH where broadcasters directly connect to consumers and can actually grow revenues with a growth in the subscriber base.
Why do Doordarshan, Zee, Star think DTH will work in India?
Today, broadcasters believe that the market is ripe for DTH. The prices of the dish and the set-top box have come down significantly. Overall investments required in putting up a DTH infrastructure has dropped and customers are also reaping the benefits of more attractive tariffs.
The major thing that DTH operators are betting on is that the service is coming at a time when the government is pushing for CAS (conditional access system), which will make cable television more expensive, narrowing the tariff gap between DTH and cable.
Will DTH be cheaper than cable or more expensive?
DTH will be definitely more expensive than cable as it exists today.
A set-top box is a must for DTH. Earlier, when CAS made set-top box mandatory for households, the costs between DTH and cable would not have been too wide.
But CAS on the backburner now -- which means no set-top box (a must for DTH), the price gap between DTH and cable will be wide.
In Oct 2002, Siticable, which is owned by Zee, said that the cost of the installation equipment, which includes the receiver dish and the set-top box, would be priced at around Rs 3,900. Siticable is looking to rope in 1 million subscribers in 15 months.
Other estimates say that digital cable set-top box may cost Rs 4,000, a DTH decoder dish is unlikely to cost less than Rs 7,000.
DTH's minimum subscription could be priced around Rs 500 per month.
Some reports say that an entry level DTH STB will cost about Rs 7,000 (including taxes and installation cost at consumers end). A more advanced STB with value added features like PVR (Personal Video Recorder), PSTN connectivity, Gamming console, channel management system, etc. may cost as much as Rs 15,000.
What is the history of DTH in India?
DTH services were first proposed in India in 1996. But they did not pass approval because there were concerns over national security and a cultural invasion. In 1997, the government even imposed a ban when the Rupert Murdoch-owned Indian Sky Broadcasting (ISkyB) was about to launch its DTH services in India.Finally in 2000, DTH was allowed. The new policy requires all operators to set up earth stations in India within 12 months of getting a license. DTH licenses in India will cost $2.14 million and will be valid for 10 years. The companies offering DTH service will have to have an Indian chief and foreign equity has been capped at 49 per cent. There is no limit on the number of companies that can apply for the DTH license.
So, what's the buzz? Will DTH finally be the one that rules?
The cable system is well entrenched in India and is showing quite rapid growth. If DTH had come to India in 1996-97 (like Star had originally attempted), then it could have made a significant breakthrough.Europe is an example of this. DTH developed there before cable and now controls nearly 80 per cent of the total satellite television subscriber base. But in US, cable rules because it came before DTH.
DTH will definitely cut into the existing cable user base. It will make the local cable operator less important and take business away from him. It will give consumers greater choice.
But it is likely to be an up market premium product and most middle class households will stick to cable.
What Is "In"
.in is the Internet country code top-level domain (ccTLD) for India. The domain is operated by INRegistry under the authority of NIXI, the National Internet Exchange of India. INRegistry was appointed by the government of India.
As of 2005, liberalised policies for the .in domain allow unlimited second-level registrations under .in. Unlimited registrations under the previously structured existing zones are also allowed:
.in (available to anyone; used by companies, individuals, and organizations in India)
.co.in (originally for banks, registered companies, and trademarks)
.firm.in (originally for shops, partnerships, liaison offices, sole proprietorships)
.net.in (originally for Internet service providers)
.org.in (originally for non-profit organizations)
.gen.in (originally for general/miscellaneous use)
.ind.in (originally for individuals)
Six zones are reserved for use by qualified organizations in India:
.ac.in (Academic institutions)
.edu.in (Educational institutions)
.res.in (Indian research institutes)
.ernet.in (Older, for both educational and research institutes)
.gov.in (Indian government)
.mil.in (Indian military)
Before the introduction of liberalised registration policies for the .in domain, only 7000 names had been registered between 1992 and 2004. As of March 2010, the number had increased to over 610,000 domain names, with 60% of registrations coming from India, rest from overseas.[1] This domain is popular for domain hacks.
The domain .nic.in is reserved for India's National Informatics Centre, but in practice most Indian government agencies have domains ending in .nic.in.
Internationalized domain names and country codes
Internationalized domain names and country codes
India plans to introduce internationalized domain names, that is domain names in 22 local languages used in India. They are planned to be introduced in mid-2012.[dated info][2]
These internationalized domain names will be used together with seven new top domains for India.[3]
These top domains are:
.भारत (Devanagari)
.ਭਾਰਤ (Gurmukhī)
.ભારત (Gujarati)
.இந்தியா (Tamil)
.భారత్ (Telugu)
.ভারত (Bengali)
.بھارت (Urdu)
Windows 7
Unlike Windows Vista, which introduced a large number of new features, Windows 7 was intended to be a more focused, incremental upgrade to the Windows line, with the goal of being compatible with applications and hardware with which Windows Vista was already compatible. Presentations given by Microsoft in 2008 focused on multi-touch support, a redesigned Windows shell with a new taskbar, referred to as the Superbar, a home networking system called Home Group, and performance improvements. Some standard applications that have been included with prior releases of Microsoft Windows, including Windows Calendar, Windows Mail, Windows Movie Maker, and Windows Photo Gallery, are not included in Windows 7;most are instead offered separately at no charge as part of the Windows Essentials suite.
Hardware requirements
Computers that display this sticker meet the requirements for Windows 7.
Microsoft has published the minimum specifications for a system to run Windows 7.
Requirements for the 32-bit version are similar to that of premium editions of Vista, but are higher for 64-bit versions. Microsoft has released an upgrade advisor that determines if a computer is compatible with Windows 7.
Minimum hardware requirements for Windows 7
Architecture 32-bit 64-bit
Processor 1 GHz IA-32 processor 1 GHz x86-64 processor
Memory (RAM) 1 GB 2 GB
Graphics card DirectX 9 graphics processor with WDDM driver model 1.0
(Not absolutely necessary; only required for Aero)
HDD free space 16 GB of free disk space 20 GB of free disk space
Optical drive DVD-ROM drive(Only to install from DVD-ROM media)
SATA AHCI
What Is "Ozone"
Ozone
Ozone or trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope (O2), breaking down with a half life of about half an hour in the lower atmosphere, to normal dioxygen. Ozone is formed from dioxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
Ozone was proposed as a new substance in air in 1840, and named, even before its chemical nature was known, after the Greek verb ozein , from the peculiar odor after lightning storms. Ozone's odor is sharp, reminiscent of chlorine, and detectable by many people at concentrations of as little as 10 parts per billion in air. Ozone's O3 formula was determined in 1865. The molecule was later proven to have a bent structure and to be diamagnetic. In standard conditions, ozone is a pale blue gas that condenses at progressively cryogenic temperatures to a dark blue liquid and finally a violet-black solid. Ozone's instability with regard to more common dioxygen is such that both concentrated gas and liquid ozone may decompose explosively. It is therefore used commercially only in low concentrations.
Ozone is a powerful oxidant (far more so than dioxygen) and has many industrial and consumer applications related to oxidization. This same high oxidizing potential, however, causes ozone to damage mucus and respiratory tissues in animals, and also tissues in plants, above concentrations of about 100 parts per billion. This makes ozone a potent respiratory hazard and pollutant near ground level. However, the so-called ozone layer (a portion of the stratosphere with a higher concentration of ozone, from two to eight ppm) is beneficial, preventing damaging ultraviolet light from reaching the Earth's surface, to the benefit of both plants and animals.
History
Ozone, the first allotrope of any chemical element to be recognized, was proposed as a distinct chemical substance by Christian Friedrich Schönbein in 1840, who named it after the Greek verb ozein (ὄζειν, "to smell"), from the peculiar odor in lightning storms.The formula for ozone, O3, was not determined until 1865 by Jacques-Louis Soret
and confirmed by Schönbein in 1867
What Is "Physics"
Physics is a natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force.More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy.Over the last two millennia, physics was a part of natural philosophy along with chemistry, certain branches of mathematics, and biology, but during the Scientific Revolution in the 17th century, the natural sciences emerged as unique research programs in their own right Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms of other sciences, while opening new avenues of research in areas such as mathematics and philosophy.
Physics also makes significant contributions through advances in new technologies that arise from theoretical breakthroughs. For example, advances in the understanding of electromagnetism or nuclear physics led directly to the development of new products which have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus.
Classical physics
Classical physics includes the traditional branches and topics that were recognized and well-developed before the beginning of the 20th century—classical mechanics, acoustics, optics, thermodynamics, and electromagnetism. Classical mechanics) is concerned with bodies acted on by forces and bodies in motion and may be divided into statics (study of the forces on a body or bodies at rest), kinematics (study of motion without regard to its causes), and dynamics (study of motion and the forces that affect it); mechanics may also be divided into solid mechanics and fluid mechanics (known together as continuum mechanics), the latter including such branches as hydrostatics, hydrodynamics, aerodynamics, and pneumatics. Acoustics, the study of sound, is often considered a branch of mechanics because sound is due to the motions of the particles of air or other medium through which sound waves can travel and thus can be explained in terms of the laws of mechanics. Among the important modern branches of acoustics is ultrasonics, the study of sound waves of very high frequency beyond the range of human hearing. Optics, the study of light, is concerned not only with visible light but also with infrared and ultraviolet radiation, which exhibit all of the phenomena of visible light except visibility, e.g., reflection, refraction, interference, diffraction, dispersion, and polarization of light. Heat is a form of energy, the internal energy possessed by the particles of which a substance is composed; thermodynamics deals with the relationships between heat and other forms of energy. Electricity and magnetism have been studied as a single branch of physics since the intimate connection between them was discovered in the early 19th century; an electric current gives rise to a magnetic field and a changing magnetic field induces an electric current. Electrostatics deals with electric charges at rest, electrodynamics with moving charges, and magnetostatics with magnetic poles at rest.
Modern physics
Classical physics is generally concerned with matter and energy on the normal scale of observation, while much of modern physics is concerned with the behavior of matter and energy under extreme conditions or on the very large or very small scale. For example, atomic and nuclear physics studies matter on the smallest scale at which chemical elements can be identified. The physics of elementary particles is on an even smaller scale, as it is concerned with the most basic units of matter; this branch of physics is also known as high-energy physics because of the extremely high energies necessary to produce many types of particles in large particle accelerators. On this scale, ordinary, commonsense notions of space, time, matter, and energy are no longer valid.
The two chief theories of modern physics present a different picture of the concepts of space, time, and matter from that presented by classical physics. Quantum theory is concerned with the discrete, rather than continuous, nature of many phenomena at the atomic and subatomic level, and with the complementary aspects of particles and waves in the description of such phenomena. The theory of relativity is concerned with the description of phenomena that take place in a frame of reference that is in motion with respect to an observer; the special theory of relativity is concerned with relative uniform motion in a straight line and the general theory of relativity with accelerated motion and its connection with gravitation. Both quantum theory and the theory of relativity find applications in all areas of modern physics.
Difference between classical and modern physics
While physics aims to discover universal laws, its theories lie in explicit domains of applicability. Loosely speaking, the laws of classical physics accurately describe systems whose important length scales are greater than the atomic scale and whose motions are much slower than the speed of light. Outside of this domain, observations do not match their predictions. Albert Einstein contributed the framework of special relativity, which replaced notions of absolute time and space with spacetime and allowed an accurate description of systems whose components have speeds approaching the speed of light. Max Planck, Erwin Schrödinger, and others introduced quantum mechanics, a probabilistic notion of particles and interactions that allowed an accurate description of atomic and subatomic scales. Later, quantum field theory unified quantum mechanics and special relativity. General relativity allowed for a dynamical, curved spacetime, with which highly massive systems and the large-scale structure of the universe can be well-described. General relativity has not yet been unified with the other fundamental descriptions; several candidate theories of quantum gravity are being developed.ALL IN WEB
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