Thermodynamics Essay Research Paper ThermodynamicsYou arrive at

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Thermodynamics Essay, Research Paper Thermodynamics You arrive at your office and unpack your breakfast. The piping-hot tea and chilly orange juice you purchased just minutes ago are now both lukewarm. Why can t the tea steal heat from the juice to stay hot? Why does even the most state-of-the-art car operate at a mere 30 percent efficiency? Why can t some genius create a perpetual motion machine? The answers lie in the field of thermodynamics. Thermodynamics is the study of the mechanical action or relations of heat. It turns out that the flow of heat from the tea into the air- or from any body into a cooler one, for that matter- defines the flow of time itself. Earlier is, by definition, the time when the cup was hot, later the time when it is cool (Von Baeyer xiv). This

idea is what gave scientists the concept of real and imaginary time. Stephen Hawking says, Imaginary time is indistinguishable from directions in space. If one can go north, one can turn around and head south; equally, if one can go forward in imaginary time, one ought to be able to turn around and go backward (Hawking 182). Real time on the other hand follows certain arrows, or directions in space. This is where the difference between past and future comes from. This is why we remember the past but not the future. In his book Maxwell s Demon, Von Baeyer explains how without this arrow of time provided by thermodynamics, we would be living in a reversible world, in which time could flow forward, backward, or not at all (Von Baeyer xiv). In this essay I will explain further how

the flow of heat, or increase in disorder of the universe, is intimately related to the forward progression of the time that we experience. If an arrow is drawn arbitrarily, and if as one follows this arrow, he finds more and more of the random element in the state of the world, then the arrow is pointing towards the future; if the random element decreases, the arrow points towards the past (Fraser 100). Stephen Hawking described these arrows of time in his book The Illustrated A Brief History of Time. He says, there are at least three different arrows of time. First there is the thermodynamic arrow of time, the direction of time in which disorder or entropy increases. Then there is the psychological arrow of time. This is the direction in which we feel time passes, the direction

in which we remember the past but not the future. Finally there is the cosmological arrow of time. This is the direction of time in which the universe is expanding rather than contracting (Hawking 184-5). Now that we ve given time the property of direction, we can begin to try to understand the thermodynamic progression of time. Assuming that the universe has no boundary, it can be argued that all of Hawking s arrows point in the same direction. He says the psychological arrow is determined by the thermodynamic arrow, and that these two arrows necessarily always point in the same direction. [And] There must be well-defined thermodynamic and cosmological arrows of time, but they will not point in the same direction for the whole history of the universe it is only when they do that

conditions are suitable for the development of intelligent beings (Hawking 186). As far as humans are concerned, the thermodynamic arrow of time gives rise to the laws of thermodynamics. The First Law of Thermodynamics is the law of conservation of energy. It states that energy cannot be created or destroyed. Instead it is converted from one form to another, such as from work to heat, from heat to light, or from chemical to heat, or such. As the universe expands, energy tends towards unordered states, but it is not increased or decreased in total relative amount. The Second Law of Thermodynamics has several variations. One version says that some heat is always wasted when converting heat into mechanical energy. Another states that heat normally flows from high to low