Third law of Thermodynamics: is it broken?

There are always some invisible barriers in the physical science - the edge of the detectable universe-the cosmological horizon is one, and the relativistic speed limit,Beyond which no object can accelerate, is another .A third such barrier is absolute zero Temperature, the state beyond which matter cannot be cooled, in which all molecular motion ceases .

Absolute zero, as a theoretical concept, was found as early as 1699, in the work of the French physicist Guillaume Amontons, conducted experiments in temperature and it’s measurement, but still it is a mystery why it is unattainable. The numerical value of absolute zero is -273.15 degrees Celsius or -459.67 degrees Fahrenheit.

The first significant step in the direction of achieving absolute zero was taken in the 1880s when a French mining engineer named Louis-Paul Cailetet liquefied Oxygen,At about-200 degrees Fahrenheit .Today, when temperature of less than a degree above Absolute zero are achievable, this trend continues at the University of Florida, is Gainesville, where a new cryogenics laboratory has been opened recently.

The first law of thermodynamics (also known as law of conservation of energy) holds that energy can neither created nor destroyed. It establishes an exact relation between heat and work. But it does not tell us the direction of energy transformation.

The second law, which governs the direction of the flow of heat, dictates that during every transformation of energy, a certain amount is dissipated and so, is unavailable for doing work. It introduces a new thermodynamic variable named Entropy which is the measurement of disorder. With disorder, entropy increases.

By an orderly sate of molecules in a substance we mean that at any instant we can be sure in specifying their arrangement within the substance.

The third one was proposed, in 1906, by Walther Nernst, of the University of Berlin (for which he won the 1920 Nobel Prize in chemistry).

Physicists previously had assumed that, when cooled, molecules and atoms gradually slow down until, at absolute zero, they come to rest. But Quantum Mechanics does not allow that. The lowest energy available to an atom, called its ground state energy, is not zero. The associated with this state cannot be shared with other objects ( it cannot “flow”) or be interpreted as heat, so it does not count as disorderliness. Reasoning in this manner, Nernst reached at a new understanding of absolute zero: rather than the absence of motion, it indicates the absence of disorder, that means, a state of perfect order.

Surveying the specific heat –six year latter Nernst discovered a remarkable fact: During the approach toward absolute zero, or perfect order, each step is more difficult than the preceding one. Temperature decreases less with each successive removal of heat. Nernst proposed a stronger form of the third law: Absolute zero is unattainable.

In principle, according to the statistical nature of order, there is a small but finite probability that an object will reach a temperature of a billionth of a Kelvin, or even zero. This is the base of Gainesville physicists.

Oceans Control Global Weather

By pumping massive amounts of heat through the oceans, vast ocean currents control weather and climate on land.

American statesman, inventor, and scientist Benjamin Franklin conducted the first scientific investigation of the Gulf Stream at 1770 and discovered its importance to Earth’s weather

and climate. His work launched scientific study of ocean currents, ocean temperature, the

interaction of ocean current with winds, and the effect of ocean currents on climate. Franklin’s discoveries mark the beginnings of modern oceanographic science.

The Atlantic Ocean’s Gulf Stream is the most important of our world’s ocean currents.

It is a major heat engine, carrying massive amounts of warm water north to warm Europe. It

has directed the patterns of ocean exploration and commerce and may be a major determinant of the onset of ice ages. Finally, it is the key to understanding global circulation patterns and the interconnectedness of the world’s oceans, weather, and climates.

The Gulf Stream is bigger than the combined flow of the Mississippi, the Nile, the Congo, the Amazon, the Volga, the Yangtze,and virtually every other major river in the world.

Cancer and Power lines

Epidemiologists in Denver , Los Angeles and Sweden are asking us to believe that magnetic fields of 2 milligauss from power distribution lines are a serious cause of childhood Leukemia . And they believe that low frequency electromagnetic fields ( like ovens and TV sets) of modern life threaten our health .

However, laboratory studies on animals and cell cultures have shown that weak magnetic fields can have effects on several biological processes. For example, they may alter hormone and enzyme levels and the rate of movement of some chemicals through living tissue. In the long term, they may have an effect on the incidence of cancer or other adverse health effects.

But the studies have been criticized . The studies were using data gathered from second hand

sources . They all suffer inadequate statistical samples ; in some cases , it is as little as only one case of cancer per year . The studies are mutually inconsistent and self- contradictory .

Well , "Do the all-pervasive low-frequency electromagnetic fields of modern life threaten our health ? Most probably not , judging from comparisons with the natural fields present in the

environment and in our bodies ." said William R. Bennett Jr , is a professor of Physics at

Yale University .

Well , Let's consider some natural sources of exposure .

The Earth's magnetic field is generated predominantly by circulating currents of uncertain origin well below the crust . The fields varies over the Earth's surface from about 300 mG at the equator to 700 mG at the poles .A representative value over the continental United States is

about 450 mG , about 200 times that from typical distribution lines . The magnetic field may vary about 0.1-0.3 mG due to photoionization of molecules in the upper atmosphere . For unusual solar activity sudden fluctuations often exceed 100 mG .

Again Earth's static electric field is directed downward normal to the earth's surface and is about

120 V/m near ground level , about three times the field from a 12-KV distribution line .

So, If you live in a house near one of these high-voltage power lines, you shoud not move.

But based on what we know now, we can never say there is no risk, but we can say that the risk appears to be extremely small.

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