For the album by Off Minor, see The Heat Death of the Universe. The idea of heat death stems from the second law of thermodynamics, of which one version states that entropy tends to increase in an isolated system. The conjecture that all bodies in the universe cool off, eventually becoming too cold to support life, seems to have been first put forward by the French astronomer Jean Sylvain Bailly in 1777 in his writings on the history of astronomy and nonequilibrium entropy production in open and closed quantum systems PDF the ensuing correspondence with Voltaire.
Författare: Sebastian Deffner.
Thermodynamics is a phenomenological theory describing the energy conversion of work and heat. At its origins thermodynamics was developed in order to understand and improve heat engines. In conventional thermodynamics, however, only such processes are completely describable which are slow enough to keep the system of interest in an equilibrium state with its thermal environment at all times. On the contrary, all real physical processes are accompanied by non-equilibrium phenomena. These are mathematically described with the help of the irreversible entropy production. Moreover, the modern trend of miniaturization leads to smaller and smaller devices. On short length scales thermal noise as well as quantum fluctuations become important. Thus, usual thermodynamic quantities as work and heat acquire stochastic nature.The present dissertation contributes to this prevailing field by the derivation of analytical expressions for the entropy production in open and closed quantum system far from thermal equilibrium. To this end, it was dealt with methods and approaches of statistical physics, conventional thermodynamics, quantum information theory and the theory of open quantum systems.
The idea of heat death of the universe derives from discussion of the application of the first two laws of thermodynamics to universal processes. Lord Kelvin originated the idea of universal heat death in 1852. In 1852, Thomson published On a Universal Tendency in Nature to the Dissipation of Mechanical Energy, in which he outlined the rudiments of the second law of thermodynamics summarized by the view that mechanical motion and the energy used to create that motion will naturally tend to dissipate or run down. The result would inevitably be a state of universal rest and death, if the universe were finite and left to obey existing laws.
Proposals about the final state of the universe depend on the assumptions made about its ultimate fate, and these assumptions have varied considerably over the late 20th century and early 21st century. In a hypothesized „open“ or „flat“ universe that continues expanding indefinitely, either a heat death or a Big Rip is expected to eventually occur. Max Planck wrote that the phrase „entropy of the universe“ has no meaning because it admits of no accurate definition. A recent analysis of entropy states, „The entropy of a general gravitational field is still not known“, and, „gravitational entropy is difficult to quantify“.
The analysis considers several possible assumptions that would be needed for estimates and suggests that the observable universe has more entropy than previously thought. This is because the analysis concludes that supermassive black holes are the largest contributor. A History of Modern Planetary Physics: Nebulous Earth. On the Dynamical Theory of Heat, with numerical results deduced from Mr Joule’s equivalent of a Thermal Unit, and M. Energy and Empire: A Biographical Study of Lord Kelvin. On the Age of the Sun’s Heat“. Archived from the original on 22 May 2011.
Disturbing Implications of a Cosmological Constant“. A dying universe: the long-term fate and evolution of astrophysical objects“. Particle emission rates from a black hole: Massless particles from an uncharged, nonrotating hole“. Spontaneous Inflation and Origin of the Arrow of Time“. Interplay between quantum phase transitions and the behavior of quantum correlations at finite temperatures. International Journal of Modern Physics B. Spontaneous entropy decrease and its statistical formula“.
Sinks in the landscape, Boltzmann brains and the cosmological constant problem“. Journal of Cosmology and Astroparticle Physics. The fate of the universe: heat death, Big Rip or cosmic consciousness? Sean Carroll, „Fluctuations in de Sitter Space“ FQXi conference 2014 in Vieques.
De Sitter Space Without Dynamical Quantum Fluctuations“. Irreversibility and the Second Law of Thermodynamics“. Entropy and the Time Evolution of Macroscopic Systems. A Larger Estimate of the Entropy of the Universe“. Time, laws, and future of cosmology“. Initially amorphous cubes gradually transform into ordered 3D meshes of crystalline nanowires as summarized in the model below. Self-organization occurs in many physical, chemical, biological, robotic, and cognitive systems.