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Negative temperature

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additional energy reduces the entropy, since it moves the system further from a 50/50 mixture. This reduction in entropy with the addition of energy corresponds to a negative temperature. In NMR spectroscopy, this corresponds to pulses with a pulse width of over 180° (for a given spin). While relaxation is fast in solids, it can take several seconds in solutions and even longer in gases and in ultracold systems; several hours were reported for silver and rhodium at picokelvin temperatures. It is still important to understand that the temperature is negative only with respect to nuclear spins. Other degrees of freedom, such as molecular vibrational, electronic and electron spin levels are at a positive temperature, so the object still has positive sensible heat. Relaxation actually happens by exchange of energy between the nuclear spin states and other states (e.g. through the
1774: 2823: 1340: 2228: 1769:{\displaystyle {\begin{aligned}\beta &={\frac {1}{k_{\mathrm {B} }}}{\frac {\delta _{2\varepsilon }}{2\varepsilon }}\\&={\frac {1}{2\varepsilon }}\left(\ln \Omega _{E+\varepsilon }-\ln \Omega _{E-\varepsilon }\right)\\&={\frac {1}{2\varepsilon }}\ln \left({\frac {\left({\frac {N+j-1}{2}}\right)!\left({\frac {N-j+1}{2}}\right)!}{\left({\frac {N+j+1}{2}}\right)!\left({\frac {N-j-1}{2}}\right)!}}\right)\\&={\frac {1}{2\varepsilon }}\ln \left({\frac {N-j+1}{N+j+1}}\right).\end{aligned}}} 2818:{\displaystyle {\begin{aligned}Z(T)&=e^{-0\beta }+2e^{-1\beta }+e^{-2\beta }\\&=1+2e^{-\beta }+e^{-2\beta }\\E(T)&={\frac {0e^{-0\beta }+2\times 1e^{-1\beta }+2e^{-2\beta }}{Z}}\\&={\frac {2e^{-\beta }+2e^{-2\beta }}{Z}}\\&={\frac {2e^{-\beta }+2e^{-2\beta }}{1+2e^{-\beta }+e^{-2\beta }}}\\S(T)&=k_{\text{B}}\ln \left(1+2e^{-\beta }+e^{-2\beta }\right)+{\frac {2e^{-\beta }+2e^{-2\beta }}{\left(1+2e^{-\beta }+e^{-2\beta }\right)T}}\end{aligned}}} 875: 853: 864: 97:. The possibility of a decrease in entropy as energy increases requires the system to "saturate" in entropy. This is only possible if the number of high energy states is limited. For a system of ordinary (quantum or classical) particles such as atoms or dust, the number of high energy states is unlimited (particle momenta can in principle be increased indefinitely). Some systems, however (see the 899: 640: 498: 22: 2177: 738:. In this case, energy flows fairly rapidly among the spin states of interacting atoms, but energy transfer between the nuclear spins and other modes is relatively slow. Since the energy flow is predominantly within the spin system, it makes sense to think of a spin temperature that is distinct from the temperature associated to other modes. 155:(Kelvin) scale can be loosely interpreted as the average kinetic energy of the system's particles. The existence of negative temperature, let alone negative temperature representing "hotter" systems than positive temperature, would seem paradoxical in this interpretation. The paradox is resolved by considering the more rigorous definition of 578::+0 K (−273.15 °C), …, +100 K (−173.15 °C), …, +300 K (+26.85 °C), …, +1000 K (+726.85 °C), …, +∞ K (+∞ °C), −∞ K (−∞ °C), …, −1000 K (−1273.15 °C), …, −300 K (−573.15 °C), …, −100 K (−373.15 °C), …, −0 K (−273.15 °C). 465:, a function of the possible microstates of the system, and temperature conveys information on the distribution of energy levels among the possible microstates. For systems with many degrees of freedom, the statistical and thermodynamic definitions of entropy are generally consistent with each other. 2871:
In the absence of a magnetic field, such a two-spin system would have maximum entropy when half the atoms are in the spin-up state and half are in the spin-down state, and so one would expect to find the system with close to an equal distribution of spins. Upon application of a magnetic field, some
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Negative temperatures can only exist in a system where there are a limited number of energy states (see below). As the temperature is increased on such a system, particles move into higher and higher energy states, and as the temperature increases, the number of particles in the lower energy states
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must also be bounded by the finite area. Bounded phase space is the essential property that allows for negative temperatures, and can occur in both classical and quantum systems. As shown by Onsager, a system with bounded phase space necessarily has a peak in the entropy as energy is increased. For
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The two-dimensional systems of vortices confined to a finite area can form thermal equilibrium states at negative temperature, and indeed negative temperature states were first predicted by Onsager in his analysis of classical point vortices. Onsager's prediction was confirmed experimentally for a
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In many familiar physical systems, temperature is associated to the kinetic energy of atoms. Since there is no upper bound on the momentum of an atom, there is no upper bound to the number of energy states available when more energy is added, and therefore no way to get to a negative temperature.
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Some theorists have proposed using an alternative definition of entropy as a way to resolve perceived inconsistencies between statistical and thermodynamic entropy for small systems and systems where the number of states decreases with energy, and the temperatures derived from these entropies are
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Since we started with over half the atoms in the spin-down state, this initially drives the system towards a 50/50 mixture, so the entropy is increasing, corresponding to a positive temperature. However, at some point, more than half of the spins are in the spin-up position. In this case, adding
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regime, it is possible to go from a low entropy positive temperature state to a low entropy negative temperature state. In the negative temperature state, the atoms macroscopically occupy the maximum momentum state of the lattice. The negative temperature ensembles equilibrated and showed long
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temperature/coldness conversion scale: Temperatures on the Kelvin scale are shown in blue (Celsius scale in green, Fahrenheit scale in red), coldness values in gigabyte per nanojoule are shown in black. Infinite temperature (coldness zero) is shown at the top of the diagram; positive values of
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The limited range of states accessible to a system with negative temperature means that negative temperature is associated with emergent ordering of the system at high energies. For example in Onsager's point-vortex analysis negative temperature is associated with the emergence of large-scale
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of the atoms will tend to align so as to minimize the energy of the system, thus slightly more atoms should be in the lower-energy state (for the purposes of this example we will assume the spin-down state is the lower-energy state). It is possible to add energy to the spin system using
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for systems with limited states.) By injecting energy into these systems in the right fashion, it is possible to create a system in which there are more particles in the higher energy states than in the lower ones. The system can then be characterised as having a negative temperature.
1228: 2868:, meaning that they correspond to the same energy. When an external magnetic field is applied, the energy levels are split, since those spin states that are aligned with the magnetic field will have a different energy from those that are anti-parallel to it. 478: 137:
It seems negative temperatures were first found experimentally in 1951, when Purcell and Pound observed evidence for them in the nuclear spins of a lithium fluoride crystal placed in a magnetic field, and then removed from this field.  They wrote:
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of temperature, being the more fundamental quantity. Systems with a positive temperature will increase in entropy as one adds energy to the system, while systems with a negative temperature will decrease in entropy as one adds energy to the system.
830:, is added to the system. This is the "normal" condition in the macroscopic world, and is always the case for the translational, vibrational, rotational, and non-spin-related electronic and nuclear modes. The reason for this is that there are an 73:
than any system with a positive temperature. If a negative-temperature system and a positive-temperature system come in contact, heat will flow from the negative- to the positive-temperature system. A standard example of such a system is
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A system in a negative temperature state is not cold, but very hot, giving up energy to any system at positive temperature put into contact with it. It decays to a normal state through infinite temperature.
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Gauthier, G.; Reeves, M. T.; Yu, X.; Bradley, A. S.; Baker, M. A.; Bell, T. A.; Rubinsztein-Dunlop, H.; Davis, M. J.; Neely, T. W. (2019). "Giant vortex clusters in a two-dimensional quantum fluid".
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Johnstone, S. P.; Groszek, A. J.; Starkey, P. T.; Billinton, C. J.; Simula, T. P.; Helmerson, K. (2019). "Evolution of large-scale flow from turbulence in a two-dimensional superfluid".
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clusters of vortices. This spontaneous ordering in equilibrium statistical mechanics goes against common physical intuition that increased energy leads to increased disorder.
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scales. This phenomenon was first discovered at the University of Alberta. This should be distinguished from temperatures expressed as negative numbers on non-thermodynamic
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However, in some situations, it is possible to isolate one or more of the modes. In practice, the isolated modes still exchange energy with the other modes, but the
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number of these types of modes, and adding more heat to the system increases the number of modes that are energetically accessible, and thus increases the entropy.
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The previous example is approximately realized by a system of nuclear spins in an external magnetic field. This allows the experiment to be run as a variation of
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modes of a system determines the macroscopic temperature. In a "normal" system, thermal energy is constantly being exchanged between the various modes.
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different. It has been argued that the new definition would create other inconsistencies; its proponents have argued that this is only apparent.
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below), have a maximum amount of energy that they can hold, and as they approach that maximum energy their entropy actually begins to decrease.
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Shen, Jian-Qi (2003). "Anti-shielding Effect and Negative Temperature in Instantaneously Reversed Electric Fields and Left-Handed Media".
2856:. In the case of electronic and nuclear spin systems, there are only a finite number of modes available, often just two, corresponding to 480: 1077: 4486: 3711: 1223:{\displaystyle \Omega _{E}={\binom {N}{\frac {N+j}{2}}}={\frac {N!}{\left({\frac {N+j}{2}}\right)!\left({\frac {N-j}{2}}\right)!}}.} 946: 687: 545: 114: 626:
However, in statistical mechanics, temperature can correspond to other degrees of freedom than just kinetic energy (see below).
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This entire proof assumes the microcanonical ensemble with energy fixed and temperature being the emergent property. In the
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Hanggi, Peter; Hilbert, Stefan; Dunkel, Jorn (2016). "Meaning of temperature in different thermostatistical ensembles".
3706:. World Scientific series in 20th century physics, v. 21. Singapore; River Edge, N.J.: World Scientific. p. 417. 909: 650: 508: 4383:
Schmidt, Harry; Mahler, Günter (2005). "Control of Local Relaxation Behavior in Closed Bipartite Quantum Systems".
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For the system to have a ground state, the trace to converge, and the density operator to be generally meaningful,
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and in the higher energy states approaches equality. (This is a consequence of the definition of temperature in
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over any cyclical process is zero. For a system in which the entropy is purely a function of the system's energy
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Following the previous example, we choose a state with two levels and two particles. This leads to microstates
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Varga, Peter (1998). "Minimax games, spin glasses, and the polynomial-time hierarchy of complexity classes".
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Dunkel, Jorn; Hilbert, Stefan (2013). "Consistent thermostatistics forbids negative absolute temperatures".
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of this exchange is much slower than for the exchanges within the isolated mode. One example is the case of
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When the temperature is negative, higher energy states are more likely to be occupied than low energy ones.
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Braun, S.; Ronzheimer, J. P.; Schreiber, M.; Hodgman, S. S.; Rom, T.; Bloch, I.; Schneider, U. (2013).
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Braun, S.; Ronzheimer, J. P.; Schreiber, M.; Hodgman, S. S.; Rom, T.; Bloch, I.; Schneider, U. (2013).
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Parihar, V.; Widom, A.; Srivastava, Y. (2006). "Thermal Time Scales in a Color Glass Condensate".
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Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
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and changing the overall harmonic potential from trapping to anti-trapping, thus transforming the
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atoms. This was done by tuning the interactions of the atoms from repulsive to attractive using a
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Frenkel, Daan; Warren, Patrick B. (2015-02-01). "Gibbs, Boltzmann, and negative temperatures".
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as energy increases, and high-energy states necessarily have negative Boltzmann temperature.
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confined within a finite area, and realized that since their positions are not independent
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Spectroscopy with coherent radiation: selected papers of Norman F. Ramsey with commentary
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Entropy, thermodynamic beta, and temperature as a function of the energy for a system of
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Montgomery, D. C. (1972). "Two-dimensional vortex motion and "negative temperatures"".
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Hsu, W.; Barakat, R. (1992). "Statistics and thermodynamics of luminescent radiation".
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coldness/temperature are on the right-hand side, negative values on the left-hand side.
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Purcell, E. M.; Pound, R. V. (1951). "A nuclear spin system at negative temperature".
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in which the interaction term becomes negligible. The total energy of the system is
568: 198: 79: 66: 58: 54: 4430: 3931:(1974). "Negative Temperature States of Two-Dimensional Plasmas and Vortex Fluids". 3685: 3519: 3455: 4375: 4273: 4153: 3873: 3598: 3378: 3267: 3119: 1068:
is the number of particles with positive energy minus the number of particles with
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The simplest example, albeit a rather nonphysical one, is to consider a system of
3382: 3271: 4575: 1936:, the temperature is fixed and energy is the emergent property. This leads to ( 978: 898: 742: 705: 639: 497: 152: 122: 86: 4414: 4312: 3140:. Performing this transformation adiabatically while keeping the atoms in the 4017: 3800: 3677: 3572: 3402: 3337: 3291: 4535: 4257: 4137: 4076: 3857: 3763: 3721: 3227:"Comment on: Negative Kelvin temperatures: some anomalies and a speculation" 977:
but are otherwise noninteracting. This can be understood as a limit of the
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Castle, J.; Emmerich, W.; Heikes, R.; Miller, R.; Rayne, J. (1965).
3253: 69:. A system with a truly negative temperature on the Kelvin scale is 4120: 4059: 3486: 4240: 3840: 3547: 3430: 2897: 724: 476: 20: 4328:
Mosk, A. (2005). "Atomic Gases at Negative Kinetic Temperature".
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for a single mode of a luminescent radiation field at frequency
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energies exceeding the value where the peak occurs, the entropy
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The possibility of negative temperatures was first predicted by
90: 4224:"Negative Absolute Temperature for Motional Degrees of Freedom" 3824:"Negative Absolute Temperature for Motional Degrees of Freedom" 3601:(1951-01-15). "A Nuclear Spin System at Negative Temperature". 892: 633: 582:
The corresponding inverse temperature scale, for the quantity
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A substance with a negative temperature is not colder than
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is defined in terms of temperature. This is reversed here,
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Negative temperatures have also been achieved in motional
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must itself be negative, implying a negative temperature.
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Carr, Lincoln D. (2013-01-04). "Negative Temperatures?".
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lasers) are in excited states. This is referred to as a
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and never need to enter a negative temperature regime.
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particles, each of which can take an energy of either
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The Laws of Thermodynamics: A Very Short Introduction
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The Laws of Thermodynamics: A Very Short Introduction
3003: 2936: 2231: 1949: 1788: 1343: 1250: 1093: 990: 754: 371: 348:{\displaystyle T=\left({\frac {dS}{dE}}\right)^{-1}.} 297: 218: 266:{\displaystyle T={\frac {dQ_{\mathrm {rev} }}{dS}}.} 3737:
Spin Dynamics: Basics of Nuclear Magnetic Resonance
799:{\displaystyle T={\frac {dq_{\mathrm {rev} }}{dS}}} 3145:lifetimes in an anti-trapping harmonic potential. 3067: 2979: 2900:systems, wherein a large fraction of the system's 2817: 2171: 1921: 1768: 1285: 1222: 1042: 798: 431: 347: 265: 4203:Science by Degrees: Temperature from Zero to Zero 3308:Onsager, L. (1949). "Statistical Hydrodynamics". 1136: 1110: 3764:"Positive and negative picokelvin temperatures" 1235:fundamental assumption of statistical mechanics 573: 4488:Towards Quantum Magnetism with Ultracold Atoms 2896:This phenomenon can also be observed in many 1286:{\displaystyle S=k_{\text{B}}\ln \Omega _{E}} 700:The distribution of energy among the various 575:The temperature scale from cold to hot runs: 89:cannot achieve negative temperatures: adding 8: 4508:Negative temperature, at about 48min. 53sec. 3934:Proceedings of the Royal Society of London A 2980:{\displaystyle H=(h\nu -\mu )a^{\dagger }a.} 190:is a function of the change in the system's 3387:. Oxford University Press. pp. 10–14. 3276:. Oxford University Press. pp. 89–95. 927:. Unsourced material may be challenged and 668:. Unsourced material may be challenged and 526:. 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So if 1296:We can solve for thermodynamic beta ( 288:, the temperature can be defined as: 85:Thermodynamic systems with unbounded 65:, which are nevertheless higher than 7: 3225:Tremblay, André-Marie (1975-11-18). 925:adding citations to reliable sources 666:adding citations to reliable sources 524:adding citations to reliable sources 163:. This reveals the tradeoff between 887:noninteracting two-level particles. 813:corresponds to the condition where 113:in 1949. Onsager was investigating 4498:. ETH Zurich, ITS-MMS; Switzerland 4485:Ketterle, Wolfgang (22 Sep 2010). 1475: 1450: 1369: 1274: 1114: 1095: 843:Noninteracting two-level particles 779: 776: 773: 745:can be based on the relationship: 243: 240: 237: 121:from their momenta, the resulting 39:negative thermodynamic temperature 14: 4470:10.1238/Physica.Regular.068a00087 2904:(for chemical and gas lasers) or 2876:techniques. This causes atoms to 809:The relationship suggests that a 1080:with this amount of energy is a 897: 873: 862: 851: 638: 618:is considered more natural than 496: 362:, or "coldness", is defined as 3098:is negative semidefinite, then 821:, increases as thermal energy, 171:contained in the system, with " 2958: 2943: 2631: 2625: 2376: 2370: 2245: 2239: 2149: 2143: 2117: 2111: 2030: 2024: 1963: 1957: 1883: 1871: 1857: 1845: 1798: 1792: 1399: 1393: 1: 4496:The Zurich Physics Colloquium 4360:10.1103/PhysRevLett.95.040403 3149:Two-dimensional vortex motion 98: 3990:Il Nuovo Cimento (1943-1954) 3911:10.1016/0375-9601(72)90302-7 2990:The density operator in the 4568:"−K: Negative Temperatures" 3986:"Statistical hydrodynamics" 3735:Levitt, Malcolm H. (2008). 3535:American Journal of Physics 3234:American Journal of Physics 3106:Motional degrees of freedom 2880:from spin-down to spin-up. 161:Boltzmann's entropy formula 4630: 4415:10.1103/PhysRevE.72.016117 4313:10.1103/PhysRevC.73.017901 3984:Onsager, L. (1949-03-01). 2886:nuclear Overhauser effect 2828:The resulting values for 1326:) by considering it as a 185:thermodynamic temperature 157:thermodynamic temperature 147:Definition of temperature 4580:University of Nottingham 3801:10.1103/PhysRevB.46.6760 3678:10.1103/PhysRevE.57.6487 3128:Bose-Hubbard Hamiltonian 2992:grand canonical ensemble 2864:, these spin states are 1940:refers to microstates): 630:Temperature and disorder 4536:10.1126/science.1232558 4330:Physical Review Letters 4258:10.1126/science.1227831 4138:10.1126/science.aat5793 4077:10.1126/science.aat5718 3858:10.1126/science.1227831 1239:microcanonical ensemble 93:always increases their 3955:10.1098/rspa.1974.0018 3623:10.1103/PhysRev.81.279 3504:10.1098/rsta.2015.0039 3212:10.1103/PhysRev.103.20 3069: 2981: 2860:. In the absence of a 2819: 2173: 2070: 1993: 1923: 1779:hence the temperature 1770: 1287: 1237:, the entropy of this 1224: 1076:, the total number of 1044: 1020: 800: 580: 489: 433: 349: 267: 45:can be expressed as a 30: 3070: 2982: 2858:spin up and spin down 2820: 2174: 2050: 1973: 1924: 1771: 1288: 1225: 1045: 1000: 801: 734:in a strong external 561:statistical mechanics 487: 434: 350: 268: 24: 3001: 2934: 2914:population inversion 2229: 1947: 1786: 1341: 1248: 1091: 1082:binomial coefficient 988: 921:improve this section 811:positive temperature 752: 662:improve this section 520:improve this section 369: 295: 216: 76:population inversion 4528:2013Sci...339...42C 4462:2003PhyS...68...87S 4407:2005PhRvE..72a6117S 4352:2005PhRvL..95d0403M 4305:2006PhRvC..73a7901P 4250:2013Sci...339...52B 4130:2019Sci...364.1267J 4114:(6447): 1267–1271. 4069:2019Sci...364.1264G 4053:(6447): 1264–1267. 4002:1949NCim....6S.279O 3947:1974RSPSA.336..257E 3903:1972PhLA...39....7M 3850:2013Sci...339...52B 3793:1992PhRvB..46.6760H 3660:1998PhRvE..57.6487V 3615:1951PhRv...81..279P 3557:2015AmJPh..83..163F 3496:2016RSPTA.37450039H 3440:2014NatPh..10...67D 3322:1949NCim....6S.279O 3246:1976AmJPh..44..994T 3204:1956PhRv..103...20R 3168:Negative resistance 2888:with other spins). 1330:without taking the 1072:. From elementary 1060:is the sign of the 463:statistical entropy 4566:Moriarty, Philip. 4207:Walker and Company 4010:10.1007/BF02780991 3480:(2064): 20150039. 3330:10.1007/BF02780991 3124:Feshbach resonance 3112:degrees of freedom 3065: 2977: 2840:all increase with 2815: 2813: 2169: 2167: 1934:canonical ensemble 1919: 1766: 1764: 1328:central difference 1283: 1220: 1040: 796: 612:Boltzmann constant 490: 448:Boltzmann constant 429: 360:thermodynamic beta 345: 280:, the integral of 263: 183:The definition of 119:degrees of freedom 31: 4385:Physical Review E 4289:(17901): 017901. 4283:Physical Review C 4193:978-0-7167-1088-2 3941:(1606): 257–271. 3890:Physics Letters A 3787:(11): 6760–6767. 3780:Physical Review B 3746:978-0-470-51117-6 3700:Ramsey, Norman F. 3638:Physical Review E 3565:10.1119/1.4895828 3448:10.1038/nphys2815 3394:978-0-19-957219-9 3283:978-0-19-957219-9 3060: 2809: 2648: 2616: 2519: 2462: 2163: 2134: 2048: 1896: 1824: 1821: 1753: 1705: 1676: 1666: 1631: 1594: 1559: 1518: 1436: 1411: 1375: 1264: 1215: 1205: 1176: 1134: 1133: 957: 956: 949: 794: 698: 697: 690: 556: 555: 548: 485: 424: 404: 391: 327: 258: 197:under reversible 63:Fahrenheit scales 41:; that is, their 4619: 4583: 4555: 4510: 4505: 4503: 4493: 4481: 4455: 4453:cond-mat/0302351 4434: 4400: 4398:quant-ph/0502181 4379: 4345: 4343:cond-mat/0501344 4324: 4298: 4277: 4243: 4218: 4197: 4182:(2nd ed.). 4158: 4157: 4123: 4103: 4097: 4096: 4062: 4042: 4036: 4035: 4033: 4032: 3981: 3975: 3974: 3921: 3915: 3914: 3884: 3878: 3877: 3843: 3819: 3813: 3812: 3774: 3768: 3767: 3760: 3751: 3750: 3732: 3726: 3725: 3696: 3690: 3689: 3671: 3653: 3651:cond-mat/9604030 3644:(6): 6487–6492. 3633: 3627: 3626: 3591: 3585: 3584: 3550: 3530: 3524: 3523: 3489: 3469: 3460: 3459: 3433: 3413: 3407: 3406: 3379:Atkins, Peter W. 3375: 3369: 3368: 3356: 3350: 3349: 3310:Il Nuovo Cimento 3305: 3296: 3295: 3268:Atkins, Peter W. 3264: 3258: 3257: 3231: 3222: 3216: 3215: 3184: 3156:quantum vortices 3139: 3101: 3097: 3093: 3083: 3074: 3072: 3071: 3066: 3061: 3059: 3058: 3054: 3053: 3027: 3026: 3011: 2986: 2984: 2983: 2978: 2970: 2969: 2926: 2843: 2839: 2835: 2831: 2824: 2822: 2821: 2816: 2814: 2810: 2808: 2804: 2800: 2799: 2798: 2780: 2779: 2752: 2751: 2750: 2729: 2728: 2712: 2707: 2703: 2702: 2701: 2683: 2682: 2650: 2649: 2646: 2617: 2615: 2614: 2613: 2595: 2594: 2572: 2571: 2570: 2549: 2548: 2532: 2524: 2520: 2515: 2514: 2513: 2492: 2491: 2475: 2467: 2463: 2458: 2457: 2456: 2435: 2434: 2407: 2406: 2387: 2362: 2361: 2343: 2342: 2315: 2311: 2310: 2292: 2291: 2270: 2269: 2221: 2211: 2201: 2191: 2178: 2176: 2175: 2170: 2168: 2164: 2156: 2136: 2135: 2132: 2103: 2102: 2098: 2097: 2080: 2079: 2069: 2064: 2049: 2041: 2016: 2015: 2011: 2010: 1992: 1987: 1939: 1928: 1926: 1925: 1920: 1915: 1914: 1906: 1902: 1901: 1897: 1895: 1869: 1843: 1825: 1823: 1822: 1819: 1813: 1805: 1775: 1773: 1772: 1767: 1765: 1758: 1754: 1752: 1735: 1718: 1706: 1704: 1693: 1685: 1681: 1677: 1675: 1671: 1667: 1662: 1645: 1636: 1632: 1627: 1610: 1603: 1599: 1595: 1590: 1573: 1564: 1560: 1555: 1538: 1531: 1519: 1517: 1506: 1498: 1494: 1490: 1489: 1488: 1464: 1463: 1437: 1435: 1424: 1416: 1412: 1410: 1402: 1392: 1391: 1378: 1376: 1374: 1373: 1372: 1359: 1325: 1324: 1322: 1321: 1310: 1307: 1292: 1290: 1289: 1284: 1282: 1281: 1266: 1265: 1262: 1229: 1227: 1226: 1221: 1216: 1214: 1210: 1206: 1201: 1190: 1181: 1177: 1172: 1161: 1154: 1146: 1141: 1140: 1139: 1129: 1118: 1113: 1103: 1102: 1067: 1064:th particle and 1063: 1059: 1049: 1047: 1046: 1041: 1030: 1029: 1019: 1014: 976: 969: 962: 952: 945: 941: 938: 932: 901: 893: 886: 877: 866: 855: 829: 820: 805: 803: 802: 797: 795: 793: 785: 784: 783: 782: 762: 741:A definition of 693: 686: 682: 679: 673: 642: 634: 621: 617: 609: 605: 604: 602: 601: 596: 593: 551: 544: 540: 537: 531: 500: 492: 486: 460: 456: 445: 438: 436: 435: 430: 425: 423: 415: 407: 405: 397: 392: 390: 379: 354: 352: 351: 346: 341: 340: 332: 328: 326: 318: 310: 287: 283: 276:Entropy being a 272: 270: 269: 264: 259: 257: 249: 248: 247: 246: 226: 208: 196: 189: 49:quantity on the 4629: 4628: 4622: 4621: 4620: 4618: 4617: 4616: 4587: 4586: 4565: 4562: 4522:(6115): 42–43. 4513: 4501: 4499: 4491: 4484: 4440:Physica Scripta 4437: 4382: 4327: 4280: 4221: 4200: 4194: 4180:Thermal Physics 4170: 4167: 4165:Further reading 4162: 4161: 4105: 4104: 4100: 4044: 4043: 4039: 4030: 4028: 3983: 3982: 3978: 3923: 3922: 3918: 3886: 3885: 3881: 3834:(6115): 52–55. 3821: 3820: 3816: 3776: 3775: 3771: 3762: 3761: 3754: 3747: 3734: 3733: 3729: 3714: 3698: 3697: 3693: 3635: 3634: 3630: 3603:Physical Review 3593: 3592: 3588: 3532: 3531: 3527: 3471: 3470: 3463: 3415: 3414: 3410: 3395: 3377: 3376: 3372: 3358: 3357: 3353: 3307: 3306: 3299: 3284: 3266: 3265: 3261: 3254:10.1119/1.10248 3240:(10): 994–995. 3229: 3224: 3223: 3219: 3192:Physical Review 3186: 3185: 3181: 3176: 3164: 3151: 3131: 3116:optical lattice 3108: 3099: 3095: 3085: 3079: 3039: 3035: 3028: 3012: 2999: 2998: 2961: 2932: 2931: 2924: 2894: 2874:radio frequency 2850: 2841: 2837: 2833: 2829: 2812: 2811: 2784: 2768: 2758: 2754: 2753: 2736: 2717: 2713: 2687: 2671: 2661: 2657: 2641: 2634: 2619: 2618: 2599: 2583: 2573: 2556: 2537: 2533: 2522: 2521: 2499: 2480: 2476: 2465: 2464: 2442: 2420: 2392: 2388: 2379: 2364: 2363: 2347: 2331: 2313: 2312: 2296: 2277: 2255: 2248: 2227: 2226: 2219: 2213: 2209: 2203: 2199: 2193: 2189: 2183: 2166: 2165: 2127: 2120: 2105: 2104: 2089: 2081: 2071: 2033: 2018: 2017: 2002: 1994: 1966: 1945: 1944: 1937: 1870: 1844: 1838: 1831: 1827: 1826: 1814: 1806: 1784: 1783: 1763: 1762: 1736: 1719: 1713: 1697: 1683: 1682: 1646: 1640: 1611: 1605: 1604: 1574: 1568: 1539: 1533: 1532: 1526: 1510: 1496: 1495: 1474: 1449: 1442: 1438: 1428: 1414: 1413: 1403: 1380: 1379: 1363: 1351: 1339: 1338: 1332:continuum limit 1317: 1311: 1308: 1305: 1304: 1302: 1297: 1273: 1257: 1246: 1245: 1191: 1185: 1162: 1156: 1155: 1147: 1119: 1108: 1094: 1089: 1088: 1070:negative energy 1065: 1061: 1058: 1054: 1021: 986: 985: 971: 964: 960: 953: 942: 936: 933: 918: 902: 891: 890: 889: 888: 884: 880: 879: 878: 869: 868: 867: 858: 857: 856: 845: 840: 828: 822: 818: 786: 767: 763: 750: 749: 694: 683: 677: 674: 659: 643: 632: 619: 615: 607: 597: 594: 591: 590: 588: 583: 579: 552: 541: 535: 532: 517: 501: 477: 475: 458: 454: 443: 416: 408: 383: 367: 366: 319: 311: 305: 304: 293: 292: 285: 281: 250: 231: 227: 214: 213: 207: 201: 194: 187: 165:internal energy 149: 107: 17: 12: 11: 5: 4627: 4626: 4623: 4615: 4614: 4609: 4604: 4599: 4589: 4588: 4585: 4584: 4561: 4560:External links 4558: 4557: 4556: 4511: 4482: 4435: 4380: 4325: 4296:hep-ph/0505199 4278: 4234:(6115): 52–5. 4219: 4198: 4192: 4166: 4163: 4160: 4159: 4098: 4037: 3996:(2): 279–287. 3976: 3925:Edwards, S. F. 3916: 3879: 3814: 3769: 3752: 3745: 3727: 3712: 3691: 3669:10.1.1.306.470 3628: 3609:(2): 279–280. 3595:Purcell, E. M. 3586: 3541:(2): 163–170. 3525: 3461: 3418:Nature Physics 3408: 3393: 3381:(2010-03-25). 3370: 3361:Physics Review 3351: 3316:(2): 279–287. 3297: 3282: 3270:(2010-03-25). 3259: 3217: 3188:Ramsey, Norman 3178: 3177: 3175: 3172: 3171: 3170: 3163: 3160: 3150: 3147: 3142:Mott insulator 3107: 3104: 3076: 3075: 3064: 3057: 3052: 3049: 3046: 3042: 3038: 3034: 3031: 3025: 3022: 3019: 3015: 3009: 3006: 2988: 2987: 2976: 2973: 2968: 2964: 2960: 2957: 2954: 2951: 2948: 2945: 2942: 2939: 2893: 2890: 2862:magnetic field 2849: 2846: 2826: 2825: 2807: 2803: 2797: 2794: 2791: 2787: 2783: 2778: 2775: 2771: 2767: 2764: 2761: 2757: 2749: 2746: 2743: 2739: 2735: 2732: 2727: 2724: 2720: 2716: 2710: 2706: 2700: 2697: 2694: 2690: 2686: 2681: 2678: 2674: 2670: 2667: 2664: 2660: 2656: 2653: 2644: 2640: 2637: 2635: 2633: 2630: 2627: 2624: 2621: 2620: 2612: 2609: 2606: 2602: 2598: 2593: 2590: 2586: 2582: 2579: 2576: 2569: 2566: 2563: 2559: 2555: 2552: 2547: 2544: 2540: 2536: 2530: 2527: 2525: 2523: 2518: 2512: 2509: 2506: 2502: 2498: 2495: 2490: 2487: 2483: 2479: 2473: 2470: 2468: 2466: 2461: 2455: 2452: 2449: 2445: 2441: 2438: 2433: 2430: 2427: 2423: 2419: 2416: 2413: 2410: 2405: 2402: 2399: 2395: 2391: 2385: 2382: 2380: 2378: 2375: 2372: 2369: 2366: 2365: 2360: 2357: 2354: 2350: 2346: 2341: 2338: 2334: 2330: 2327: 2324: 2321: 2318: 2316: 2314: 2309: 2306: 2303: 2299: 2295: 2290: 2287: 2284: 2280: 2276: 2273: 2268: 2265: 2262: 2258: 2254: 2251: 2249: 2247: 2244: 2241: 2238: 2235: 2234: 2217: 2207: 2197: 2187: 2180: 2179: 2162: 2159: 2154: 2151: 2148: 2145: 2142: 2139: 2130: 2126: 2123: 2121: 2119: 2116: 2113: 2110: 2107: 2106: 2101: 2096: 2092: 2088: 2084: 2078: 2074: 2068: 2063: 2060: 2057: 2053: 2047: 2044: 2039: 2036: 2034: 2032: 2029: 2026: 2023: 2020: 2019: 2014: 2009: 2005: 2001: 1997: 1991: 1986: 1983: 1980: 1976: 1972: 1969: 1967: 1965: 1962: 1959: 1956: 1953: 1952: 1930: 1929: 1918: 1913: 1910: 1905: 1900: 1894: 1891: 1888: 1885: 1882: 1879: 1876: 1873: 1868: 1865: 1862: 1859: 1856: 1853: 1850: 1847: 1841: 1837: 1834: 1830: 1817: 1812: 1809: 1803: 1800: 1797: 1794: 1791: 1777: 1776: 1761: 1757: 1751: 1748: 1745: 1742: 1739: 1734: 1731: 1728: 1725: 1722: 1716: 1712: 1709: 1703: 1700: 1696: 1691: 1688: 1686: 1684: 1680: 1674: 1670: 1665: 1661: 1658: 1655: 1652: 1649: 1643: 1639: 1635: 1630: 1626: 1623: 1620: 1617: 1614: 1608: 1602: 1598: 1593: 1589: 1586: 1583: 1580: 1577: 1571: 1567: 1563: 1558: 1554: 1551: 1548: 1545: 1542: 1536: 1529: 1525: 1522: 1516: 1513: 1509: 1504: 1501: 1499: 1497: 1493: 1487: 1484: 1481: 1477: 1473: 1470: 1467: 1462: 1459: 1456: 1452: 1448: 1445: 1441: 1434: 1431: 1427: 1422: 1419: 1417: 1415: 1409: 1406: 1401: 1398: 1395: 1390: 1387: 1383: 1371: 1366: 1362: 1357: 1354: 1352: 1350: 1347: 1346: 1315: 1294: 1293: 1280: 1276: 1272: 1269: 1260: 1256: 1253: 1231: 1230: 1219: 1213: 1209: 1204: 1200: 1197: 1194: 1188: 1184: 1180: 1175: 1171: 1168: 1165: 1159: 1153: 1150: 1144: 1138: 1132: 1128: 1125: 1122: 1117: 1112: 1106: 1101: 1097: 1056: 1051: 1050: 1039: 1036: 1033: 1028: 1024: 1018: 1013: 1010: 1007: 1003: 999: 996: 993: 955: 954: 905: 903: 896: 882: 881: 872: 871: 870: 861: 860: 859: 850: 849: 848: 847: 846: 844: 841: 839: 836: 826: 807: 806: 792: 789: 781: 778: 775: 770: 766: 760: 757: 736:magnetic field 696: 695: 646: 644: 637: 631: 628: 577: 554: 553: 504: 502: 495: 474: 471: 440: 439: 428: 422: 419: 414: 411: 403: 400: 395: 389: 386: 382: 377: 374: 358:Equivalently, 356: 355: 344: 339: 336: 331: 325: 322: 317: 314: 308: 303: 300: 278:state function 274: 273: 262: 256: 253: 245: 242: 239: 234: 230: 224: 221: 205: 148: 145: 144: 143: 106: 103: 15: 13: 10: 9: 6: 4: 3: 2: 4625: 4624: 4613: 4612:Laser science 4610: 4608: 4605: 4603: 4600: 4598: 4595: 4594: 4592: 4581: 4577: 4573: 4572:Sixty Symbols 4569: 4564: 4563: 4559: 4553: 4549: 4545: 4541: 4537: 4533: 4529: 4525: 4521: 4517: 4512: 4509: 4497: 4490: 4489: 4483: 4479: 4475: 4471: 4467: 4463: 4459: 4454: 4449: 4445: 4441: 4436: 4432: 4428: 4424: 4420: 4416: 4412: 4408: 4404: 4399: 4394: 4391:(7): 016117. 4390: 4386: 4381: 4377: 4373: 4369: 4365: 4361: 4357: 4353: 4349: 4344: 4339: 4336:(4): 040403. 4335: 4331: 4326: 4322: 4318: 4314: 4310: 4306: 4302: 4297: 4292: 4288: 4284: 4279: 4275: 4271: 4267: 4263: 4259: 4255: 4251: 4247: 4242: 4237: 4233: 4229: 4225: 4220: 4216: 4212: 4208: 4204: 4199: 4195: 4189: 4185: 4184:W. H. Freeman 4181: 4177: 4173: 4169: 4168: 4164: 4155: 4151: 4147: 4143: 4139: 4135: 4131: 4127: 4122: 4117: 4113: 4109: 4102: 4099: 4094: 4090: 4086: 4082: 4078: 4074: 4070: 4066: 4061: 4056: 4052: 4048: 4041: 4038: 4027: 4023: 4019: 4015: 4011: 4007: 4003: 3999: 3995: 3991: 3987: 3980: 3977: 3972: 3968: 3964: 3960: 3956: 3952: 3948: 3944: 3940: 3936: 3935: 3930: 3929:Taylor, J. B. 3926: 3920: 3917: 3912: 3908: 3904: 3900: 3896: 3892: 3891: 3883: 3880: 3875: 3871: 3867: 3863: 3859: 3855: 3851: 3847: 3842: 3837: 3833: 3829: 3825: 3818: 3815: 3810: 3806: 3802: 3798: 3794: 3790: 3786: 3782: 3781: 3773: 3770: 3765: 3759: 3757: 3753: 3748: 3742: 3738: 3731: 3728: 3723: 3719: 3715: 3713:9789810232504 3709: 3705: 3701: 3695: 3692: 3687: 3683: 3679: 3675: 3670: 3665: 3661: 3657: 3652: 3647: 3643: 3639: 3632: 3629: 3624: 3620: 3616: 3612: 3608: 3604: 3600: 3596: 3590: 3587: 3582: 3578: 3574: 3570: 3566: 3562: 3558: 3554: 3549: 3544: 3540: 3536: 3529: 3526: 3521: 3517: 3513: 3509: 3505: 3501: 3497: 3493: 3488: 3483: 3479: 3475: 3468: 3466: 3462: 3457: 3453: 3449: 3445: 3441: 3437: 3432: 3427: 3423: 3419: 3412: 3409: 3404: 3400: 3396: 3390: 3386: 3385: 3380: 3374: 3371: 3367:(2): 279–280. 3366: 3362: 3355: 3352: 3347: 3343: 3339: 3335: 3331: 3327: 3323: 3319: 3315: 3311: 3304: 3302: 3298: 3293: 3289: 3285: 3279: 3275: 3274: 3269: 3263: 3260: 3255: 3251: 3247: 3243: 3239: 3235: 3228: 3221: 3218: 3213: 3209: 3205: 3201: 3197: 3193: 3189: 3183: 3180: 3173: 3169: 3166: 3165: 3161: 3159: 3157: 3148: 3146: 3143: 3138: 3134: 3129: 3125: 3121: 3117: 3113: 3105: 3103: 3092: 3088: 3082: 3062: 3055: 3050: 3047: 3044: 3040: 3036: 3032: 3029: 3023: 3020: 3017: 3013: 3007: 3004: 2997: 2996: 2995: 2993: 2974: 2971: 2966: 2962: 2955: 2952: 2949: 2946: 2940: 2937: 2930: 2929: 2928: 2922: 2917: 2915: 2911: 2910:semiconductor 2907: 2903: 2899: 2891: 2889: 2887: 2881: 2879: 2875: 2869: 2867: 2863: 2859: 2855: 2848:Nuclear spins 2847: 2845: 2805: 2801: 2795: 2792: 2789: 2785: 2781: 2776: 2773: 2769: 2765: 2762: 2759: 2755: 2747: 2744: 2741: 2737: 2733: 2730: 2725: 2722: 2718: 2714: 2708: 2704: 2698: 2695: 2692: 2688: 2684: 2679: 2676: 2672: 2668: 2665: 2662: 2658: 2654: 2651: 2642: 2638: 2636: 2628: 2622: 2610: 2607: 2604: 2600: 2596: 2591: 2588: 2584: 2580: 2577: 2574: 2567: 2564: 2561: 2557: 2553: 2550: 2545: 2542: 2538: 2534: 2528: 2526: 2516: 2510: 2507: 2504: 2500: 2496: 2493: 2488: 2485: 2481: 2477: 2471: 2469: 2459: 2453: 2450: 2447: 2443: 2439: 2436: 2431: 2428: 2425: 2421: 2417: 2414: 2411: 2408: 2403: 2400: 2397: 2393: 2389: 2383: 2381: 2373: 2367: 2358: 2355: 2352: 2348: 2344: 2339: 2336: 2332: 2328: 2325: 2322: 2319: 2317: 2307: 2304: 2301: 2297: 2293: 2288: 2285: 2282: 2278: 2274: 2271: 2266: 2263: 2260: 2256: 2252: 2250: 2242: 2236: 2225: 2224: 2223: 2216: 2206: 2196: 2186: 2160: 2157: 2152: 2146: 2140: 2137: 2128: 2124: 2122: 2114: 2108: 2099: 2094: 2090: 2086: 2082: 2076: 2072: 2066: 2061: 2058: 2055: 2051: 2045: 2042: 2037: 2035: 2027: 2021: 2012: 2007: 2003: 1999: 1995: 1989: 1984: 1981: 1978: 1974: 1970: 1968: 1960: 1954: 1943: 1942: 1941: 1935: 1916: 1911: 1908: 1903: 1898: 1892: 1889: 1886: 1880: 1877: 1874: 1866: 1863: 1860: 1854: 1851: 1848: 1839: 1835: 1832: 1828: 1815: 1810: 1807: 1801: 1795: 1789: 1782: 1781: 1780: 1759: 1755: 1749: 1746: 1743: 1740: 1737: 1732: 1729: 1726: 1723: 1720: 1714: 1710: 1707: 1701: 1698: 1694: 1689: 1687: 1678: 1672: 1668: 1663: 1659: 1656: 1653: 1650: 1647: 1641: 1637: 1633: 1628: 1624: 1621: 1618: 1615: 1612: 1606: 1600: 1596: 1591: 1587: 1584: 1581: 1578: 1575: 1569: 1565: 1561: 1556: 1552: 1549: 1546: 1543: 1540: 1534: 1527: 1523: 1520: 1514: 1511: 1507: 1502: 1500: 1491: 1485: 1482: 1479: 1471: 1468: 1465: 1460: 1457: 1454: 1446: 1443: 1439: 1432: 1429: 1425: 1420: 1418: 1407: 1404: 1396: 1388: 1385: 1381: 1364: 1360: 1355: 1353: 1348: 1337: 1336: 1335: 1333: 1329: 1320: 1314: 1300: 1278: 1270: 1267: 1258: 1254: 1251: 1244: 1243: 1242: 1240: 1236: 1217: 1211: 1207: 1202: 1198: 1195: 1192: 1186: 1182: 1178: 1173: 1169: 1166: 1163: 1157: 1151: 1148: 1142: 1130: 1126: 1123: 1120: 1115: 1104: 1099: 1087: 1086: 1085: 1083: 1079: 1075: 1074:combinatorics 1071: 1037: 1034: 1031: 1026: 1022: 1016: 1011: 1008: 1005: 1001: 997: 994: 991: 984: 983: 982: 980: 975: 968: 951: 948: 940: 930: 926: 922: 916: 915: 911: 906:This section 904: 900: 895: 894: 876: 865: 854: 842: 837: 835: 833: 825: 816: 812: 790: 787: 768: 764: 758: 755: 748: 747: 746: 744: 739: 737: 733: 730: 726: 721: 719: 715: 711: 707: 703: 702:translational 692: 689: 681: 671: 667: 663: 657: 656: 652: 647:This section 645: 641: 636: 635: 629: 627: 623: 613: 600: 586: 576: 572: 570: 569:absolute zero 565: 562: 550: 547: 539: 529: 525: 521: 515: 514: 510: 505:This section 503: 499: 494: 493: 472: 470: 466: 464: 451: 449: 426: 420: 417: 412: 409: 401: 398: 393: 387: 384: 380: 375: 372: 365: 364: 363: 361: 342: 337: 334: 329: 323: 320: 315: 312: 306: 301: 298: 291: 290: 289: 279: 260: 254: 251: 232: 228: 222: 219: 212: 211: 210: 204: 200: 199:heat transfer 193: 186: 181: 178: 174: 170: 166: 162: 158: 154: 151:The absolute 146: 141: 140: 139: 135: 131: 129: 124: 120: 116: 112: 104: 102: 100: 96: 92: 88: 83: 81: 80:laser physics 77: 72: 68: 67:absolute zero 64: 60: 56: 52: 48: 44: 40: 36: 27: 23: 19: 4571: 4519: 4515: 4507: 4500:. Retrieved 4487: 4446:(1): 87–97. 4443: 4439: 4388: 4384: 4333: 4329: 4286: 4282: 4231: 4227: 4202: 4179: 4111: 4107: 4101: 4050: 4046: 4040: 4029:. Retrieved 3993: 3989: 3979: 3938: 3932: 3919: 3894: 3888: 3882: 3831: 3827: 3817: 3784: 3778: 3772: 3736: 3730: 3703: 3694: 3641: 3637: 3631: 3606: 3602: 3599:Pound, R. V. 3589: 3538: 3534: 3528: 3477: 3473: 3421: 3417: 3411: 3383: 3373: 3364: 3360: 3354: 3313: 3309: 3272: 3262: 3237: 3233: 3220: 3198:(1): 20–28. 3195: 3191: 3182: 3152: 3136: 3132: 3120:potassium-39 3109: 3090: 3086: 3080: 3077: 2989: 2918: 2895: 2882: 2877: 2870: 2865: 2851: 2827: 2214: 2204: 2194: 2184: 2181: 1931: 1778: 1318: 1312: 1298: 1295: 1232: 1052: 973: 966: 958: 943: 934: 919:Please help 907: 823: 810: 808: 740: 722: 699: 684: 675: 660:Please help 648: 624: 598: 584: 581: 574: 566: 557: 542: 533: 518:Please help 506: 467: 452: 441: 357: 275: 202: 182: 176: 159:in terms of 150: 136: 132: 127: 111:Lars Onsager 108: 84: 70: 38: 37:can achieve 32: 18: 4597:Temperature 4576:Brady Haran 4176:Kroemer, H. 3114:. Using an 2921:Hamiltonian 1078:microstates 979:Ising model 743:temperature 706:vibrational 153:temperature 123:phase space 115:2D vortices 87:phase space 43:temperature 4591:Categories 4172:Kittel, C. 4121:1801.06952 4060:1801.06951 4031:2019-11-17 3897:(1): 7–8. 3487:1507.05713 3174:References 3154:system of 2866:degenerate 725:time scale 714:electronic 710:rotational 177:reciprocal 4607:Magnetism 4552:124095369 4478:118894011 4321:119090586 4241:1211.0545 4093:195750381 4026:186224016 4018:1827-6121 3971:120771020 3841:1211.0545 3664:CiteSeerX 3581:119179342 3573:0002-9505 3548:1403.4299 3431:1304.2066 3424:(1): 67. 3403:467748903 3346:186224016 3338:1827-6121 3292:467748903 3048:β 3045:− 3033:⁡ 3021:β 3018:− 3005:ρ 2967:† 2956:μ 2953:− 2950:ν 2906:electrons 2796:β 2790:− 2777:β 2774:− 2748:β 2742:− 2726:β 2723:− 2699:β 2693:− 2680:β 2677:− 2655:⁡ 2611:β 2605:− 2592:β 2589:− 2568:β 2562:− 2546:β 2543:− 2511:β 2505:− 2489:β 2486:− 2454:β 2448:− 2432:β 2426:− 2415:× 2404:β 2398:− 2359:β 2353:− 2340:β 2337:− 2308:β 2302:− 2289:β 2283:− 2267:β 2261:− 2141:⁡ 2100:β 2091:ε 2087:− 2073:ε 2052:∑ 2013:β 2004:ε 2000:− 1975:∑ 1909:− 1887:ε 1864:− 1861:ε 1836:⁡ 1811:ε 1724:− 1711:⁡ 1702:ε 1657:− 1651:− 1579:− 1550:− 1524:⁡ 1515:ε 1486:ε 1483:− 1476:Ω 1472:⁡ 1466:− 1461:ε 1451:Ω 1447:⁡ 1433:ε 1408:ε 1389:ε 1382:δ 1349:β 1275:Ω 1271:⁡ 1196:− 1096:Ω 1035:ε 1023:σ 1002:∑ 998:ε 937:July 2024 908:does not 678:July 2024 649:does not 536:July 2024 507:does not 373:β 335:− 128:decreases 4578:for the 4544:23288530 4431:17987338 4423:16090046 4368:16090784 4266:23288533 4215:64023985 4178:(1980). 4146:31249055 4085:31249054 3866:23288533 3809:10002377 3722:38753008 3702:(1998). 3686:10964509 3520:39161351 3512:26903095 3456:16757018 3162:See also 838:Examples 832:infinite 173:coldness 99:examples 47:negative 33:Certain 4602:Entropy 4524:Bibcode 4516:Science 4492:(movie) 4458:Bibcode 4403:Bibcode 4376:1156732 4348:Bibcode 4301:Bibcode 4274:8207974 4246:Bibcode 4228:Science 4154:4948239 4126:Bibcode 4108:Science 4065:Bibcode 4047:Science 3998:Bibcode 3943:Bibcode 3899:Bibcode 3874:8207974 3846:Bibcode 3828:Science 3789:Bibcode 3656:Bibcode 3611:Bibcode 3553:Bibcode 3492:Bibcode 3436:Bibcode 3318:Bibcode 3242:Bibcode 3200:Bibcode 1323:⁠ 1303:⁠ 1233:By the 929:removed 914:sources 815:entropy 729:nuclear 718:nuclear 670:removed 655:sources 610:is the 606:(where 603:⁠ 589:⁠ 528:removed 513:sources 461:is the 446:is the 192:entropy 175:", the 169:entropy 105:History 95:entropy 59:Celsius 55:Rankine 35:systems 4550:  4542:  4476:  4429:  4421:  4374:  4366:  4319:  4272:  4264:  4213:  4190:  4152:  4144:  4091:  4083:  4024:  4016:  3969:  3961:  3872:  3864:  3807:  3743:  3720:  3710:  3684:  3666:  3579:  3571:  3518:  3510:  3454:  3401:  3391:  3344:  3336:  3290:  3280:  3094:, and 2898:lasing 2892:Lasers 2836:, and 2212:, and 1053:where 716:, and 442:where 71:hotter 51:Kelvin 4548:S2CID 4502:1 Jan 4474:S2CID 4448:arXiv 4427:S2CID 4393:arXiv 4372:S2CID 4338:arXiv 4317:S2CID 4291:arXiv 4270:S2CID 4236:arXiv 4150:S2CID 4116:arXiv 4089:S2CID 4055:arXiv 4022:S2CID 3967:S2CID 3963:78450 3959:JSTOR 3870:S2CID 3836:arXiv 3682:S2CID 3646:arXiv 3577:S2CID 3543:arXiv 3516:S2CID 3482:arXiv 3452:S2CID 3426:arXiv 3342:S2CID 3230:(PDF) 3130:from 3089:< 2902:atoms 732:spins 4540:PMID 4504:2016 4419:PMID 4364:PMID 4262:PMID 4211:LCCN 4188:ISBN 4142:PMID 4081:PMID 4014:ISSN 3862:PMID 3805:PMID 3741:ISBN 3718:OCLC 3708:ISBN 3569:ISSN 3508:PMID 3399:OCLC 3389:ISBN 3334:ISSN 3288:OCLC 3278:ISBN 2919:The 2908:(in 2878:flip 912:any 910:cite 653:any 651:cite 511:any 509:cite 167:and 91:heat 4532:doi 4520:339 4466:doi 4411:doi 4356:doi 4309:doi 4254:doi 4232:339 4134:doi 4112:365 4073:doi 4051:364 4006:doi 3951:doi 3939:336 3907:doi 3854:doi 3832:339 3797:doi 3674:doi 3619:doi 3561:doi 3500:doi 3478:374 3444:doi 3326:doi 3250:doi 3208:doi 3196:103 3135:→ − 2994:is 2927:is 2220:= 2 2210:= 1 2200:= 1 2190:= 0 1241:is 970:or 923:by 827:rev 664:by 522:by 206:rev 78:in 61:or 53:or 4593:: 4574:. 4570:. 4546:. 4538:. 4530:. 4518:. 4506:. 4494:. 4472:. 4464:. 4456:. 4444:68 4442:. 4425:. 4417:. 4409:. 4401:. 4389:72 4387:. 4370:. 4362:. 4354:. 4346:. 4334:95 4332:. 4315:. 4307:. 4299:. 4287:73 4285:. 4268:. 4260:. 4252:. 4244:. 4230:. 4226:. 4209:. 4205:. 4186:. 4174:; 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Index


SI
systems
temperature
negative
Kelvin
Rankine
Celsius
Fahrenheit scales
absolute zero
population inversion
laser physics
phase space
heat
entropy
examples
Lars Onsager
2D vortices
degrees of freedom
phase space
temperature
thermodynamic temperature
Boltzmann's entropy formula
internal energy
entropy
coldness
thermodynamic temperature
entropy
heat transfer
state function

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