Models based on general relativity play an important role in astrophysics, and the success of these models is further testament to the theory’s validity.

Gravitational lensing

Since light is deflected in a gravitational field, it is possible for the light of a distant object to reach an observer along two or more paths. For instance, light of a very distant object such as a quasar can pass along one side of a massive galaxy and be deflected slightly so as to reach an observer on Earth, while light

passing along the opposite side of that same galaxy is deflected as well, reaching the same observer from a slightly different direction. As a result, that particular observer will see one astronomical object in two different places in the night sky. This kind of focussing is well-known when it comes to optical lenses, and hence the corresponding gravitational effect is called gravitational lensing.

Observational astronomy uses lensing effects as an important tool to infer properties of the lensing object. Even in cases where that object is not directly visible, the shape of a lensed image provides information about the mass distribution responsible for the light deflection. In particular, gravitational lensing provides one way to measure the distribution of dark matter, which does not give off light and can be observed only by its gravitational effects. One particularly interesting application are large-scale observations, where the lensing masses are spread out over a significant fraction of the observable universe, and can be used to obtain information about the large-scale properties and evolution of our cosmos.

Gravitational waves

Gravitational waves, a direct consequence of Einstein’s theory, are distortions of geometry which propagate at the speed of light, and can be thought of as ripples in space-time. They should not be confused with the gravity waves of fluid dynamics, which are a different concept.

Indirectly, the effect of gravitational waves has been detected in observations of specific binary stars. Such pairs of stars orbit each other and, as they do so, gradually lose energy by emitting gravitational waves. For ordinary stars like our sun, this energy loss would be too small to be detectable, but this energy loss was observed in 1974 in a binary pulsar called PSR1913+16. In such a system, one of the orbiting stars is a pulsar. This has two consequences: a pulsar is an extremely dense object known as a neutron star, for which gravitational wave emission is much stronger than for ordinary stars. Also, a pulsar emits a narrow beam of electromagnetic radiation from its magnetic poles. As the pulsar rotates, its beam sweeps over the Earth, where it is seen as a regular series of radio pulses, just as a ship at sea observes regular flashes of light from the rotating light in a lighthouse. This regular pattern of radio pulses functions as a highly accurate “clock”. It can be used to time the double star’s orbital period, and it reacts sensitively to distortions of space-time in its immediate neighborhood.

The discoverers of PSR1913+16, Russell Hulse and Joseph Taylor, were awarded the Nobel Prize in Physics in 1993. Since then, several other binary pulsars have been found. The most useful are those in which both stars are pulsars, since they provide the most accurate tests of general relativity.

Currently, one major goal of research in relativity is the direct detection of gravitational waves. To this end, a number of land-based gravitational wave detectors are in operation, and a mission to launch a space-based detector, LISA, is currently under development, with a precursor mission (LISA Pathfinder) due for launch in June 2011. If gravitational waves are detected, they could be used to obtain information about compact objects such as neutron stars and black holes, and also to probe the state of the early universe fractions of a second after the Big Bang.

Black holes

When mass is concentrated into a sufficiently compact region of space, general relativity predicts the formation of a black hole& – a region of space with a gravitational attraction so strong that not even light can escape. Certain types of black holes are thought to be the final state in the evolution of massive stars. On the other hand, supermassive black holes with the mass of millions or billions of Suns are assumed to reside in the cores of most galaxies, and they play a key role in current models of how galaxies have formed over the past billions of years.

Matter falling onto a compact object is one of the most efficient mechanisms for releasing energy in the form of radiation, and matter falling onto black holes is thought to be responsible for some of the brightest astronomical phenomena imaginable. Notable examples of great interest to astronomers are quasars and other types of active galactic nuclei. Under the right conditions, falling matter accumulating around a black hole can lead to the formation of jets, in which focused beams of matter are flung away into space at speeds near that of light.

There are several properties that make black holes most promising sources of gravitational waves. One reason is that black holes are the most compact objects that can orbit each other as part of a binary system; as a result, the gravitational waves emitted by such a system are especially strong. Another reason follows from what are called black hole uniqueness theorems: over time, black holes retain only a minimal set of distinguishing features (since different hair styles are a crucial part of what gives different people their different appearances, these theorems have become known as “no hair” theorems). For instance, in the long term, the collapse of a hypothetical matter cube will not result in a cube-shaped black hole. Instead, the resulting black hole will be indistinguishable from a black hole formed by the collapse of a spherical mass, but with one important difference: in its transition to a spherical shape, the black hole formed by the collapse of a cube will emit gravitational waves.

Cosmology

One of the most important aspects of general relativity is that it can be applied to the universe as a whole. A key point is that, on large scales, our universe appears to be constructed along very simple lines: All current observations suggest that, on average, the structure of the cosmos should be approximately the same, regardless of an observer’s location or direction of observation: the universe is approximately homogeneous and isotropic. Such comparatively simple universes can be described by simple solutions of Einstein’s equations. The current cosmological models of the universe are obtained by combining these simple solutions to general relativity with theories describing the properties of the universe’s matter content, namely thermodynamics, nuclear- and particle physics. According to these models, our present universe emerged from an extremely dense high-temperature state (the Big Bang)

roughly 14 billion years ago, and has been expanding ever since.

Einstein’s equations can be generalized by adding a term called the cosmological constant. When this term is present, empty space itself acts as a source of attractive or, unusually, repulsive gravity. Einstein originally introduced this term in his pioneering 1917 paper on cosmology, with a very specific motivation: contemporary cosmological thought held the universe to be static, and the additional term was required for constructing static model universes within the framework of general relativity. When it became apparent that the universe is not static, but expanding, Einstein was quick to discard this additional term; prematurely, as we know today: From about 1998 on, a steadily accumulating body of astronomical evidence has shown that the expansion of the universe is accelerating in a way that suggests the presence of a cosmological constant or, equivalently, of a dark energy with specific properties that pervades all of space.

Adapted from the Wikipedia article Introduction to general relativity, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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inversion temperature in thermodynamics and cryogenics is the critical temperature below which a non-ideal gas (all gases in reality) that is expanded at constant enthalpy will experience a temperature decrease, and above which will experience a temperature increase. This temperature change is known as the Joule-Thomson effect, and is exploited in the liquefaction of gases.

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Classical mechanics was traditionally divided into three main branches:

* Statics, the study of equilibrium and its relation to forces

* Dynamics, the study of motion and its relation to forces

* Kinematics, dealing with the implications of observed motions without regard for circumstances causing them

Another division is based on the choice of mathematical formalism:

* Newtonian mechanics

* Lagrangian mechanics

* Hamiltonian mechanics

Alternatively, a division can be made by region of application:

* Celestial mechanics, relating to stars, planets and other celestial bodies

* Continuum mechanics, for materials which are modelled as a continuum, e.g., solids and fluids (i.e., liquids and gases).

* Relativistic mechanics (i.e. including the special and general theories of relativity), for bodies whose speed is close to the speed of light.

* Statistical mechanics, which provides a framework for relating the microscopic properties of individual atoms and molecules to the macroscopic or bulk thermodynamic properties of materials.

Adapted from the Wikipedia article Classical mechanics, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Adapted from the Wikipedia article Eric Lerner, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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In ancient and medieval times, the objective study of nature was known as natural philosophy. In late medieval and early modern times, a philosophical interpretation of nature was gradually replaced by a scientific approach using inductive methodology. The works of Ibn al-Haytham and Sir Francis Bacon popularized this approach, thereby helping to forge the scientific revolution.

By the 19th century, the study of science had come into the purview of professionals and institutions. In so doing, it gradually acquired the more modern name of ”natural science.” The term ”scientist” was coined by William Whewell in an 1834 review of Mary Somerville’s ”On the Connexion of the Sciences”. But the word did not enter general use until nearly the end of the same century.

According to a famous 1923 textbook ”Thermodynamics — and the Free Energy of Chemical Substances” by the American chemist Gilbert N. Lewis and the American physical chemist Merle Randall, the natural sciences contain three great branches:

Aside from the logical and mathematical sciences, there are three great branches of ”natural science” which stand apart by reason of the variety of far reaching deductions drawn from a small number of primary postulates — they are mechanics, electrodynamics, and thermodynamics.

Today, natural sciences are more commonly divided into life sciences, such as botany and zoology; and physical sciences, which include physics, chemistry, geology and astronomy.

Adapted from the Wikipedia article Natural science, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Astrophysics (Greek: ”Astro ”- meaning “star”, and Greek: ”physis ”– ”φύσις ” – meaning “nature”) is the branch of astronomy that deals with the physics of the universe, including the physical properties (luminosity, density, temperature, and chemical composition) of celestial objects such as galaxies, stars, planets, exoplanets, and the interstellar medium, as well as their interactions. The study of cosmology addresses questions of astrophysics at scales much larger than the size of particular gravitationally-bound objects in the universe.

Because astrophysics is a very broad subject, ”astrophysicists” typically apply many disciplines of physics, including mechanics, electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic and molecular physics. In practice, modern astronomical research involves a substantial amount of physics. The name of a university’s department (“astrophysics” or “astronomy”) often has to do more with the department’s history than with the contents of the programs. Astrophysics can be studied at the bachelors, masters, and Ph.D. levels in aerospace engineering, physics, or astronomy departments at many universities.

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Biophysics is an interdisciplinary science that uses the methods of physics and physical chemistry to study biological systems. Studies included under the branches of biophysics span all levels of biological organization, from the molecular scale to whole organisms and ecosystems. Biophysical research shares significant overlap with biochemistry, nanotechnology, bioengineering, agrophysics and systems biology.

Molecular biophysics typically addresses biological questions that are similar to those in biochemistry and molecular biology, but the questions are approached quantitatively. Scientists in this field conduct research concerned with understanding the interactions between the various systems of a cell, including the interactions between DNA, RNA and protein biosynthesis, as well as how these interactions are regulated. A great variety of techniques are used to answer these questions.

Fluorescent imaging techniques, as well as electron microscopy, x-ray crystallography, NMR spectroscopy and atomic force microscopy (AFM) are often used to visualize structures of biological significance. Conformational change in structure can be measured using techniques such as dual polarisation interferometry and circular dichroism. Direct manipulation of molecules using optical tweezers or AFM can also be used to monitor biological events where forces and distances are at the nanoscale. Molecular biophysicists often consider complex biological events as systems of interacting units which can be understood through statistical mechanics, thermodynamics and chemical kinetics. By drawing knowledge and experimental techniques from a wide variety of disciplines, biophysicists are often able to directly observe, model or even manipulate the structures and interactions of individual molecules or complexes of molecules.

In addition to traditional (i.e. molecular and cellular) biophysical topics like structural biology or enzyme kinetics, modern biophysics encompasses an extraordinarily broad range of research. It is becoming increasingly common for biophysicists to apply the models and experimental techniques derived from physics, as well as mathematics and statistics, to larger systems such as tissues, organs, populations and ecosystems.

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Astronomy

This discipline is the science of celestial objects and phenomena that originate outside the Earth’s atmosphere. It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the formation and development of the universe.

Astronomy includes the examination, study and modeling of stars, planets, comets, galaxies and the cosmos. Most of the information used by astronomers is gathered by remote observation, although some laboratory reproduction of celestial phenomenon has been performed (such as the molecular chemistry of the interstellar medium).

While the origins of the study of celestial features and phenomenon can be traced back to antiquity, the scientific methodology of this field began to develop in the middle of the 17th century. A key factor was Galileo’s introduction of the telescope to examine the night sky in more detail.

The mathematical treatment of astronomy began with Newton’s development of celestial mechanics and the laws of gravitation, although it was triggered by earlier work of astronomers such as Kepler. By the 19th century, astronomy had developed into a formal science, with the introduction of instruments such as the spectroscope and photography, along with much-improved telescopes and the creation of professional observatories.

Biology

This field encompasses a set of disciplines that examines phenomena related to living organisms. The scale of study can range from sub-component biophysics up to complex ecologies. Biology is concerned with the characteristics, classification and behaviors of organisms, as well as how species were formed and their interactions with each other and the environment.

The biological fields of botany, zoology, and medicine date back to early periods of civilization, while microbiology was introduced in the 17th century with the invention of the microscope. However, it was not until the 19th century that biology became a unified science. Once scientists discovered commonalities between all living things, it was decided they were best studied as a whole.

Some key developments in biology were the discovery of genetics; Darwin’s theory of evolution through natural selection; the germ theory of disease and the application of the techniques of chemistry and physics at the level of the cell or organic molecule.

Modern biology is divided into subdisciplines by the type of organism and by the scale being studied. Molecular biology is the study of the fundamental chemistry of life, while cellular biology is the examination of the cell; the basic building block of all life. At a higher level, physiology looks at the internal structure of organism, while ecology looks at how various organisms interrelate.

Chemistry

Constituting the scientific study of matter at the atomic and molecular scale, chemistry deals primarily with collections of atoms, such as gases, molecules, crystals, and metals. The composition, statistical properties, transformations and reactions of these materials are studied. Chemistry also involves understanding the properties and interactions of individual atoms for use in larger-scale applications.

Most chemical processes can be studied directly in a laboratory, using a series of (often well-tested) techniques for manipulating materials, as well as an understanding of the underlying processes. Chemistry is often called “the central science” because of its role in connecting the other natural sciences.

Early experiments in chemistry had their roots in the system of Alchemy, a set of beliefs combining mysticism with physical experiments. The science of chemistry began to develop with the work of Robert Boyle, the discoverer of gas, and Antoine Lavoisier, who developed the theory of the Conservation of mass.

The discovery of the chemical elements and the concept of Atomic Theory began to systematize this science, and researchers developed a fundamental understanding of states of matter, ions, chemical bonds and chemical reactions. The success of this science led to a complementary chemical industry that now plays a significant role in the world economy.

Earth science

Earth science (also known as geoscience, the geosciences or the Earth Sciences), is an all-embracing term for the sciences related to the planet Earth, including geology, geophysics, hydrology, meteorology, physical geography, oceanography, and soil science.

Although mining and precious stones have been human interests throughout the history of civilization, the development of the related sciences of economic geology and mineralogy did not occur until the 18th century. The study of the earth, particularly palaeontology, blossomed in the 19th century. The growth of other disciplines, such as geophysics, in the 20th century led to the development of the theory of plate tectonics in the 1960s, which has had a similar effect on the Earth sciences as the theory of evolution had on biology. Earth sciences today are closely linked to climate research and the petroleum and mineral exploration industries.

Physics

Physics embodies the study of the fundamental constituents of the universe, the forces and interactions they exert on one another, and the results produced by these interactions. In general, physics is regarded as the fundamental science, because all other natural sciences use and obey the principles and laws set down by the field. Physics relies heavily on mathematics as the logical framework for formulation and quantification of principles.

The study of the principles of the universe has a long history and largely derives from direct observation and experimentation. The formulation of theories about the governing laws of the universe has been central to the study of physics from very early on, with philosophy gradually yielding to systematic, quantitative experimental testing and observation as the source of verification.

Key historical developments in physics include Isaac Newton’s theory of universal gravitation and classical mechanics, an understanding of electricity and its relation to magnetism, Einstein’s theories of special and general relativity, the development of thermodynamics, and the quantum mechanical model of atomic and subatomic physics.

The field of physics is extremely broad, and can include such diverse studies as quantum mechanics and theoretical physics, applied physics and optics. Modern physics is becoming increasingly specialized, where researchers tend to focus on a particular area rather than being “universalists” like Albert Einstein and Lev Landau, who worked in multiple areas.

Cross-disciplines

The distinctions between the natural science disciplines are not always sharp, and they share a number of cross-discipline fields. Physics plays a significant role in the other natural sciences, as represented by astrophysics, geophysics, chemical physics and biophysics. Likewise chemistry is represented by such fields as biochemistry, geochemistry and astrochemistry.

A particular example of a scientific discipline that draws upon multiple natural sciences is environmental science. This field studies the interactions of physical, chemical and biological components of the environment, with a particular regard to the effect of human activities and the impact on biodiversity and sustainability. This science also draws upon expertise from other fields such as economics, law and social sciences.

A comparable discipline is oceanography, as it draws upon a similar breadth of scientific disciplines. Oceanography is sub-categorized into more specialized cross-disciplines, such as physical oceanography and marine biology. As the marine ecosystem is very large and diverse, marine biology is further divided into many subfields, including specializations in particular species.

There are also a subset of cross-disciplinary fields which, by the nature of the problems that they address, have strong currents that run counter to

specialization. Put another way: In some fields of integrative application, specialists in more than one field are a key part of most dialog. Such integrative fields, for example, include nanoscience, astrobiology, and complex system informatics.

Adapted from the Wikipedia article Natural science, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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By: Man Singh
Right from ancient time science has revolutionized a wheel of progress made so far. Historical contribution of science for society was initiated by Alexander Grahm Bell whose mom and students whom he married were deaf, on March 10, 1876, at small laboratory at Boston, USA, established a communication from one room to another. It led to establish Bell Telephone Company in year 1877 for quicker communication. Gregor Mendel, central European monk who published his ideas on genetics in 1866 but largely went unrecognized until 1900, and a long after his death, was recognized as father of genetics. Newton gave laws for gravitational force, Jams Watt discovered locomotive engine, Hargovind Singh khurana synthesized artificial gene and Madam Curie discovered a radioactive materials named Pitchblende in 1911. Antoine Lavoisier, a French Chemist in 1700s, put forward a quantitative basis for chemistry by measuring weights of materials used in chemical reactions. For this work, Lavoisier is known as a “father of modern chemistry. His prefixes are most important in modern day technology where decimal and exponential equivalents in a metric system are very useful and listed as pico for 10-12, nano for 10-9, micro for 10-6, milli for 10-3, centi for 10-2 for deci for 10-1, no prefix for 00, deka for 101, hepta for 102, kilo for 103,mega for 106 and giga for 109.

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Many more could be derived by conversion from one unit of length to another in a metric system by shifting a decimal point. For example 12 inches make feet and 5280 feet make a mile. There are many glaring discoveries which are indispensable from the society for example in 19th century matter and energy have been complementary to each other and has fascinated Einstein for principle of relativity. It led him to make nuclear bombs, bombarded on Hiroshima and Nagasaki, the business cities of Japan, in 1945. In a history of human civilization, it was as a 2nd sun as it generated radiations equivalent to those of sun with vas change in environmental thermodynamics. The thermos means temperature and dynamics means motion, and coined the word thermodynamics. Origin of life has been because of alignment and association of nitrogen (N2), oxygen (O2), hydrogen (H2) gases and sulfur (S) together to form amino acids, proteins to compose life system. It was put forward by Stanley who at Chicago University, USA, in 1950s did successful experiment to prove that methane (CH4) and ammonia (NH3) gases with other gases form amino acids and proteins. The alignment and association of gases conserve energy in a form of molecules, which sustain life. Newton’s observation about falling of an apple from apple tree further emphasized key position of energy. Evolution of civilization followed by various experimental realizations about energy for construction of world famous pyramid at Cairo, Egypt. Thousands years old, the workers loaded heavy and bigger sized stones on wooden planks and did swim in river Nile for transportation to pyramid site. The energy has brought revolutionary changes in civilization like Chinese and Indian inks were prepared by burning the wood to convert it into the wooden coals which were converted into fine powder and mixed with mustard oils. Similarly Harrappa and Mohan Jodaro, century old big buildings were constructed following lock and key concept based on a socket and cone joints of bones of elbow and knees of human body. At countryside, for centuries, grandmother used to burn mustard oil with cotton wick through a capillary and collect soot on neat and clean metallic surfaces like on brass or ion, and applied in eyes for adsorbing a secretion. During stone and metallic ages of civilization, the stones were shaped up to different designs and used for hunting.

These forms conserve and liberate energies transforming from one form to another as burning of oil to soot. Egyptians understood thermodynamics in a better way as they knew pushing heavy wooden planks on water surface reduces frictional forces and minimum human energy was needed for transportations. During Stone Age, the stones were shaped up to different sizes to manifolds the impulse for hunting. The water potential was noticed centuries ago and dams were constructed at Mississippi and Niles to make water falls for rotating turbine to generate electricity and irrigational works.

Paddling of cycle, letter typing machines, bull carts, churners (for churning curd to whey), horse carts, swing machines, ships were operated manually and best form of human energy conversion. The machine were run with human energy in fact if we go deeper, the human energy harnessed from food is partly stored in muscles and was used for operating the machines. Similarly levers were made which were very effective to economize the human energy for example the rollers were not pushed from back but were pulled forwards from front to minimize the human energy consumption. These scientific developments were revolved around a energy conversion from one form to another and termed as thermodynamic by Joule Thompson, Carnot and Cannon Rumford in 18th countries. Now the thermodynamics is an indispensable part of the human sciences and civilizations. In ancient times the major cities were established at the banks of rivers, due to easier transportation and as sources of water for drinking, irrigation, cottage industries. River Nile in African countries is considered highly revered and is boon to Egypt, Sudan, Ghana, Ethiopia, Somalia and Nigeria etc. In India, rivers Ganga, Yamuna, Sarswati etc. were taken in very high esteem and cities like Delhi at bank Yamuna, Allahabad at Trivani or Pragraj, kolkata at river Hugly, Mumbai and Madras are at coastal areas. The energy is understood as thermodynamics. During British India various dams for energy harnessing were constructed like Tungbhadra dam at Krishna-Cavery, Rihand, Hirakund, Nagarjun Sagar at Krishna River, Cauvery, Periyar, Ramagundam, Bhakra Nangal, and Salal project at Chenab River. Theses were eco-friendly techniques with no pollution hazards. The replacement of cycle, bull cart and horse carts by engine run motors are emitting tone and tones of CO, CO2, NO, NO2, NO3, SO2, SO3, polluting gases causing global warming.

Thermodynamics a boon:

Liberation of calories from food is well known and establish q = DE + PDV, a first law of thermodynamics. The q is heat, DE liberated energy, P pressure and DV volume change when food is digested in body. Putting no volume and pressure change the q = DE exists which decides an intake of food. Concept of eating jugglery after lunch and dinner for intake of iron and other useful vitamins is centaury old in Indian society. By practice our ancestors carried forward this tradition generation to generation, the families who used to stick to a concept of “as you eat so you reap” leads to have sound mind in sound body. The traditions of wearing types of clothes are monitored by the thermodynamics and illuminate the human side of science. Newton’s observation of falling of apple from tree to earth was based on potential energy due to height. A matter energy-relation fascinated Einstein to make nuclear bomb. Weather forecasting is a big thermodynamics, where moistures and pressure gradient are basic parameters. In villages, people still guess in advance about a rainfall by watching the movement of ants and curtains birds. The ants very accurately sense a change in humidity and start taking out their eggs from their underground nests. Similarly the tailor birds start making nests at heighted trees. The villagers guess that increases in humidity forecasts a rainfall in coming days.

During heating, the milk boils out of a heating vessel while water does not this is due to a layer formation of a fat of the milk on upper surface on heating because of low density. The layer thickens acts as cover to push back the milk vapors and kinetic energy of the milk molecules get accumulated and a state comes when the layer can not bear with the internal energy DE. It suddenly bursts out with large amount of the milk but water heating simply breaks its hydrogen bonds.

Who lays down its Foundation:

James Watt, a naughty boy, in 1750 noticed experimental relevance of thermodynamics with uplifting of a lid of kettle being used for boiling water for cooking the vegetable. Watt coined the word horsepower as horses powered water pumps in mines and laid down a foundation of railway engines. In 1799, Humphry Davy melted ice by rubbing two ice cubs together. Latter in 1824, Sadi Carnot and Cannon Ford, observed generation of heat when iron screw was used to make hole in wooden logs. It was supported by count Rumford for boring cannon experiment in 18th and early 19th century. The handle of a screw was rotated manually putting mechanical energy to work. Partly it evolved heat during process, later on the ideas of Watt, Carnot and Ford laid down a foundation of first law of thermodynamics as q = DE+PDV.  The q is heat contents, the DE internal energy1 and the PDV a mechanical work done by or on the system. It successfully converts mechanical energy into the electrical. Benjamin Thompson in 1790’s, for measuring the power of light coined the word candlepower for candlelight as standard. Similarly James Joule in 1840’s gave the Joule as standard unit for energy measurement2, which is still in use. There are several other discoveries where our ancestors developed like fire which burnt by rubbing dried wooden logs that generates fire by friction3.

Description:

 Real meaning of thermodynamics is to achieve the best equilibrium among the pressure, temperatures, mass and energy. However its real meaning could be understood by several states of the water, these are most useful example in society. At low temperature the liquid water is solid and referred to as ice while at optimum temperature is liquid state and at higher temperature i.e. 1000C the gaseous form (vapor). The vapor is powerful to generate electricity by turbine at thermal power stations. The windmills for centuries have been the most traditional power in villages for pumping out the water from the deep grounds. The air pressure for centuries is being used as a big potential by farmers to separate out the food grains from the straw of the wheat crops. In 18th centuries the watermills were emerged as a powerful source of energy from turbine attached directly to a axle fitted with grinding stones to grind wheat, maize, gram and other food grains into flour. At higher altitude the pressure is low hence cooking of vegetables takes longer time and more fuel. Training area of Nehru Institute of Mountaineering (NIM) Utterkashi is at very high altitudes, I personally observed that the cooking of rice or any food item takes longer time. In 1996, I have attended one month mountaineering course and studied this phenomenon. In general, the ladies used to wet solid grains of grams, soyabeans, peas etc, and spices in fresh and clean water before 4 to 5 hrs of cooking. This process was well known by our forefathers/ancestors. They were aware about a significance of thermodynamics. Hence used to wet the food grains in water prior cooking. It is time saving device and enriching the food in nutrients. It saves lot of fuels, and depicts that the wet food grains take comparatively less time in cooking and saves the fuel. The calorie of the 1g mol of the butane is -687.982 K calorie mol-1, and of methane –191.800 K calorie mpl-1 thus the total time 123-65 = 58 min are saved. This saves a lot of gas and the time in kitchen.

Thermodynamics for natural events:

The wetting concept of dried grains must be popularized in the society in interest of health and economic reasons. The rain is a best example of thermodynamics, the water vapors from south India to North from the oceans of Hind and Arabian oceans, and from bay of Bengal gets transported to North to fill the deficiency of the water moistures at the North India. This process is spontaneous or the natural one and is closely associated with the thermodynamics. The gallons and gallons of the water are being transported to North India through open sky. Evaporation of water moisture from the leaves of trees, herbs and shrubs do add some moisture to the amount of the already water vapor. This process of the thermodynamics highlights contributions of the trees. The society must encourage tree plantation to maintain the equilibrium and ecosystems. The learners can understand the meaning and worth of non-equilibrium system. The pressure gradient causes the energy gradient, and is calculated with DG = -2.303RT log K. The DG is free energy, K is equilibrium constant, the K= p2/p1, the p1 water vapor pressure at southern India and the p2 at the northern. At northern the vapor pressure is lower than that of the southern. The pressure moves from south to north India and could be equated with kinetics of reactions where the reactants are decomposed with time and rate of reaction is determined. A state is reached where the systems are equilibrated with respect to the concentration of the reactants. The rate constant K is as p1 at southern Û p2 at northern, and K = P2/P1. The DG is free energy, and a working capacity of environment due to pressure or moisture gradients. This clarifies the concept of Gibbs free energy, for example if the P1 = 1.5 bar and P2 = 1.0 bar, the log K = 0.17609 and the amount of DG = -1005.22 Joule mol-1kelvin-1. This is the energy, which is being used to push up the water vapor to northern India. The 1005.22 Joule mol-1kelvin-1 is being used till the P1 = P2, at this condition the K=1 and the log K=0, and the DG=0. This predicts that the movements of the water vapors are stabilized and condensation is started in a form of clouds with transition of phase. And after some time it falls in the form of rains. For farmers the thermodynamics has special significance. For example when high-pressure difference is there the storms occur that distribute the seeds of the herbal plants and other useful trees.

There are 4 seasons and the seed germination is temperature sensitive, the wheat, maize, guar gum, pulses, oil seeds etc. are sown at an optimum temperature with some moisture contents. The intelligent farmers generally wet the seed of crops overnight before sowing. It enhances the moisture contents in the seed for quicker and healthy germination. This makes a better understanding of the thermodynamic applications in farming. The plants show much growth in rainy seasons due to water in plenty. The artificial thermodynamic conditions are being generated for growing of the seeds and flowering so that fresh fruits can be had at any seasons. For example at Tamil Naidu the mango plants give fruits in all seasons, as it is coastal area where almost same temperature prevails. Human thermodynamics, the sweating in very useful phenomenon and is closely related to the human body. Due to sweating several harmful toxins come out of the body. The living in air condition (AC) is harmful to the body because the toxins get accumulated in the body and accumulation in excess causes sudden disease. Similarly other way round is also beneficial for example in winter seasons the people rub their hands to generate heat due to friction, and expose minimum surface of body to the environments to prevent dissipation of heat of the body. 

Currently, the thermodynamics is being defaced or deformed at domestic levels for example most of the ladies cook the food and for the time being store in freezes to prevent it from spoiling. It is OK that it protects the food for time being but heating eatable again and again is not good and destroys the calorie value. In general, overheating decompose and denature the food items. Some of the valuable vitamins and other chemicals get lost in heating process as vitamin C and iodine get vaporized. Overheating of the milk loses the vitamin C, similarly at kitchen ladies use oil for cooking the food, they dip the processed or knitted flour in hot oil. The used oil after cooking the food is stored and reused for further cooking. The oil after heating several times gets saturated whose intake in body along food is harmful.

The farmers do irrigate the crops for water and softening the soil for a growth of the roots and a use of earthen pots for cooling the water in summer is century old. In village is highly beneficial, this is natural cooler and do not cause any disease. There is a shortage of the electricity to run the electric coolers.

The thermodynamics is playing a glaring role in vehicular traffic, air and waterways. Too much friction between the road and outer surface of the wheels at the roads do cause some heat and wastage of the energy at roads and more fuel is used to cop up this effect. Air-cooling is most useful for dissipating the heat from oil engines during work. There are some demerits of the thermodynamics as global warming, air pollution. But the wonderful aspect of the thermodynamics is to generate electricity due the to temperature difference in water with depth of the oceans. This is called as OTEC i.e. Ocean Thermal Energy Conversion as at 4 to 8 feet deep water the temperature is lower (about 10 to 150C) while at upper surface is very high (about 350C). This difference develops the temperature gradients, thus a machine made up of metallic pipes of about 1 to 2 feet inner diameter is made in a square shape. Inside pipes, at their each corner a turbine is fitted and a volatile gas like ammonia or propane is filled inside the pipes, which due to temperature gradient runs from a high temperature to a lower. The gas on the way strikes the turbines where the latter are rotated and mechanical energy is converted into the electrical energy with suitable electric circuits. The thermodynamics is applicable to human anger as human anger is an adiabatic process. If the heat of the human is quickly dissipated, the anger of the person is cooled down and the person becomes normal. Currently Survismeter and econoburette are invented from Indian soil for saving energy and resources.

Conclusion: The best use of thermodynamic processes draws manifold benefits to our society and maintains the healthy ecosystem. This article contains a very primitive and useful science that has been enriching our civilization. The energy is still in great demand and a key for all round developments. There is an urgent need to pay attention on the trivial methods and concepts and perceptions dealing with energies, as the young minds can accelerate and develop some new dimension of science that can boost up our quality of life. There are many areas and works where least scientific attentions are paid because careful execution of any thing would up ridge some new thoughts.

References:

Man Singh and Sanjay Kumar, J. Appl. Sci., 93, 47-55, 2004. Man Singh, J. Ind. Chem. Soc. 78, August 2001, 397-402. Man Singh, J. Ind. Chem. Soc.  80, July 2003, 704-706.

Dr.Man Singh, associate prof. physical chemistry, is working on molecular features of dendrimers and supramolecues, their surface area, wetting coefficents, interaction dynamics.

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Critics to Shrödinger´ Cat

Before proceeding with the disclosures of controversial ideas of physics, let us recall one of the major mysteries of quantum mechanics, which deals with the paradox of the cat. This thought experiment was proposed by the great physicist Erwin Shrödinger that was one of the architects of revolutionary theory which along with the Theory of Relativity of Albert Einstein, led to a philosophical revolution in scientific thinking this century.

The reader may have become estranged physicists dealing with a subject that seems like a joke. Trap a cat in a box in which has a radioactive source, a radiation detector and a poisonous gas that is released when a particle is detected, killing the cat, is not only a joke, is the height of wickedness. But it’s just a thought experiment, and  say the biographers, Shrödinger was a beautiful soul. Another version is due to David Bohm that consist in a light source, a half-silvered mirror and a light detector (a photocell, for example) that is coupled to a weapon that kills the cat when a photon is detected. In this version the half-silvered mirror splits the quantum state of the incident photon in a superposition of two different states, one reflected and one that is transmitted by the mirror. The fact is that in both cases, the cat lives in a superposition of life and death. Let us now address the original version.

In the case of the cat trapped in the box, the particle detector is only triggered once per minute. Suppose the probability of

Physicist and writer. Five published books. Msc.  in science by COPPE-UFRJ (Rio de Janeiro). Phd in Physics by UFPA(Belém do Pará). Take training at Kernforschunganlage Jülich Gmbh-Germany. Professor and guide of two thesis in post-graduation. Flght-Controller. Articles published at journals. See more at Google search: “leopoldino dos santos Ferreira”.

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