| '''宇宙的热寂''',也被称为大寒或大冻结<ref>[http://map.gsfc.nasa.gov/universe/uni_fate.html WMAP – Fate of the Universe], ''WMAP's Universe'', [[NASA]]. Accessed online July 17, 2008.</ref>,是对宇宙最终命运的猜测,这表明宇宙将进化到没有热力学自由能的状态,因此将无法维持熵增的过程。热寂并不意味着任何特定的绝对温度; 它只要求温差或其他过程可能不再被利用来进行做工。用物理学的语言来说,此时宇宙达到热力学平衡(最大熵)。 | | '''宇宙的热寂''',也被称为大寒或大冻结<ref>[http://map.gsfc.nasa.gov/universe/uni_fate.html WMAP – Fate of the Universe], ''WMAP's Universe'', [[NASA]]. Accessed online July 17, 2008.</ref>,是对宇宙最终命运的猜测,这表明宇宙将进化到没有热力学自由能的状态,因此将无法维持熵增的过程。热寂并不意味着任何特定的绝对温度; 它只要求温差或其他过程可能不再被利用来进行做工。用物理学的语言来说,此时宇宙达到热力学平衡(最大熵)。 |
| 关于宇宙最终状态的提议取决于对其最终命运的假设,而这些假设在20世纪末和21世纪初有很大的不同。在一个假设的 "开放 "或 "平坦 "的宇宙中,继续无限期地膨胀,预计最终要么发生热寂,要么发生大裂变<ref>Plait, Philip (2008). ''Death from the Skies!''. Viking Adult (published 16 October 2008). p. 259. ISBN <bdi>978-0-670-01997-7</bdi>.</ref>。如果宇宙学常数为零,宇宙将在一个非常长的时间尺度内接近绝对零度。然而,如果宇宙学常数是正值,就像最近的观测<ref>Reiss; et al. (1998). "Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant". ''Astronomical Journal''. '''116''' (3): 1009–1038. arXiv:astro-ph/9805201. Bibcode:1998AJ....116.1009R. doi:10.1086/300499</ref>(2011年诺贝尔奖)所显示的那样,温度将渐进到一个非零的正值,宇宙将接近一个最大熵的状态,在这个状态下不可能有进一步的做功<ref>Dyson, Lisa; Kleban, Matthew; Susskind, Leonard (12 November 2002). "Disturbing Implications of a Cosmological Constant". ''Journal of High Energy Physics''. '''2002''' (10): 011. arXiv:hep-th/0208013. Bibcode:2002JHEP...10..011D. doi:10.1088/1126-6708/2002/10/011. S2CID 2344440.</ref>。 | | 关于宇宙最终状态的提议取决于对其最终命运的假设,而这些假设在20世纪末和21世纪初有很大的不同。在一个假设的 "开放 "或 "平坦 "的宇宙中,继续无限期地膨胀,预计最终要么发生热寂,要么发生大裂变<ref>Plait, Philip (2008). ''Death from the Skies!''. Viking Adult (published 16 October 2008). p. 259. ISBN <bdi>978-0-670-01997-7</bdi>.</ref>。如果宇宙学常数为零,宇宙将在一个非常长的时间尺度内接近绝对零度。然而,如果宇宙学常数是正值,就像最近的观测<ref>Reiss; et al. (1998). "Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant". ''Astronomical Journal''. '''116''' (3): 1009–1038. arXiv:astro-ph/9805201. Bibcode:1998AJ....116.1009R. doi:10.1086/300499</ref>(2011年诺贝尔奖)所显示的那样,温度将渐进到一个非零的正值,宇宙将接近一个最大熵的状态,在这个状态下不可能有进一步的做功<ref>Dyson, Lisa; Kleban, Matthew; Susskind, Leonard (12 November 2002). "Disturbing Implications of a Cosmological Constant". ''Journal of High Energy Physics''. '''2002''' (10): 011. arXiv:hep-th/0208013. Bibcode:2002JHEP...10..011D. doi:10.1088/1126-6708/2002/10/011. S2CID 2344440.</ref>。 |
| 从大爆炸到今天,我们认为宇宙中的物质和暗物质集中在恒星、星系和星系团中,并且推测未来依然如此。因此,宇宙并未处于热力学平衡状态,物体可以做功<ref name=":0">Adams, Fred C.; Laughlin, Gregory (1997). "A dying universe: the long-term fate and evolution of astrophysical objects". ''Reviews of Modern Physics''. '''69''' (2): 337–72. arXiv:astro-ph/9701131. Bibcode:1997RvMP...69..337A. doi:10.1103/RevModPhys.69.337. S2CID 12173790</ref>。由于霍金辐射,一个大约1个星系质量(10<sup>11</sup>个太阳质量)的超大质量黑洞的衰减时间是10<sup>100</sup>年左右<ref>See in particular equation (27) in Page, Don N. (15 January 1976). "Particle emission rates from a black hole: Massless particles from an uncharged, nonrotating hole". ''Physical Review D''. '''13''' (2): 198–206. Bibcode:1976PhRvD..13..198P. doi:10.1103/PhysRevD.13.198.</ref>,所以熵至少可以产生到那个时候。据预测,宇宙中的一些大型黑洞在星系超级星系团的坍缩过程中会继续增长,最大可能达到10<sup>14</sup>M☉。即使是这些黑洞,也会在长达10<sup>106</sup>年的时间范围内消失<ref>Frautschi, Steven (13 August 1982). "Entropy in an Expanding Universe" (PDF). ''Science''. '''217''' (4560): 593–9. Bibcode:1982Sci...217..593F. doi:10.1126/science.217.4560.593. JSTOR 1688892. <nowiki>PMID 17817517</nowiki>. S2CID 27717447. <q>Since we have assumed a maximum scale of gravitational binding—for instance, superclusters of galaxies—black hole formation eventually comes to an end in our model, with masses of up to 10<sup>14</sup><var>M</var><sub>☉</sub> ... the timescale for black holes to radiate away all their energy ranges ... to 10<sup>106</sup> years for black holes of up to 10<sup>14</sup><var>M</var><sub>☉</sub></q></ref>。在那之后,宇宙就进入了所谓的黑暗时代,预计将主要由光子和轻子的稀薄气体组成<ref name=":0" />。由于只剩下非常分散的物质,宇宙的活动将急剧减少,能量水平极低,时间尺度极长。从推测上看,宇宙有可能进入第二个膨胀时代,或者假设目前的真空状态是假真空,那么真空可能会衰变为低能量状态<ref name=":0" />。也有可能,熵的产生将停止,宇宙将达到热寂<ref name=":0" /><nowiki>。另一个宇宙可能是由随机量子波动或量子隧道在大约[math]\displaystyle 10^{10^{10^{56}}}[/math]年内产生的</nowiki><ref>Carroll, Sean M.; Chen, Jennifer (October 2004). "Spontaneous Inflation and Origin of the Arrow of Time". Bibcode:2004hep.th...10270C</ref>。有人认为,在漫长的时间里,自发的熵减少最终会庞加莱递归定理<ref>Poincaré, Henri (1890). "Sur le problème des trois corps et les équations de la dynamique". ''Acta Mathematica''. '''13''': A3–A270.</ref>、热波动<ref>Tegmark, Max (2003). "Parallel Universes". ''Scientific American''. '''288''' (2003): 40–51. arXiv:astro-ph/0302131. Bibcode:2003SciAm.288e..40T. doi:10.1038/scientificamerican0503-40. <nowiki>PMID 12701329</nowiki>.</ref><ref>Tegmark, Max (May 2003). "Parallel Universes". ''Scientific American''. '''288''' (5): 40–51. arXiv:astro-ph/0302131. Bibcode:2003SciAm.288e..40T. doi:10.1038/scientificamerican0503-40<nowiki/>PMID 12701329</ref><ref>Werlang, T.; Ribeiro, G. A. P.; Rigolin, Gustavo (2013). "Interplay between quantum phase transitions and the behavior of quantum correlations at finite temperatures". ''International Journal of Modern Physics B''. '''27''' (1n03): 1345032. arXiv:1205.1046. Bibcode:2013IJMPB..2745032W. doi:10.1142/S021797921345032X. S2CID 119264198.</ref>、和波动定理<ref>Xiu-San Xing (1 November 2007). "Spontaneous entropy decrease and its statistical formula". arXiv:0710.4624 [cond-mat.stat-mech].</ref><ref>Linde, Andrei (2007). "Sinks in the landscape, Boltzmann brains and the cosmological constant problem". ''Journal of Cosmology and Astroparticle Physics''. '''2007''' (1): 022. arXiv:hep-th/0611043. Bibcode:2007JCAP...01..022L. CiteSeerX 10.1.1.266.8334. doi:10.1088/1475-7516/2007/01/022. S2CID 16984680.</ref>的作用下发生。然而,这种情况被描述为 "高度推测,很可能是错误的,[而且]完全无法测试。<ref>Pimbblet, Kevin (3 September 2015). "The fate of the universe: heat death, Big Rip or cosmic consciousness?". ''The Conversation''.</ref>"肖恩-M-卡罗尔最初是这种想法的倡导者,但现在不再支持它了<ref>Carroll, Sean (27 January 2014). ''Sean Carroll, "Fluctuations in de Sitter Space" FQXi conference 2014 in Vieques''. FQXi.</ref><ref>Boddy, Kimberly K.; Carroll, Sean M.; Pollack, Jason (2014). "De Sitter Space Without Dynamical Quantum Fluctuations". arXiv:1405.0298 [hep-th].</ref>。 | | 从大爆炸到今天,我们认为宇宙中的物质和暗物质集中在恒星、星系和星系团中,并且推测未来依然如此。因此,宇宙并未处于热力学平衡状态,物体可以做功<ref name=":0">Adams, Fred C.; Laughlin, Gregory (1997). "A dying universe: the long-term fate and evolution of astrophysical objects". ''Reviews of Modern Physics''. '''69''' (2): 337–72. arXiv:astro-ph/9701131. Bibcode:1997RvMP...69..337A. doi:10.1103/RevModPhys.69.337. S2CID 12173790</ref>。由于霍金辐射,一个大约1个星系质量(10<sup>11</sup>个太阳质量)的超大质量黑洞的衰减时间是10<sup>100</sup>年左右<ref>See in particular equation (27) in Page, Don N. (15 January 1976). "Particle emission rates from a black hole: Massless particles from an uncharged, nonrotating hole". ''Physical Review D''. '''13''' (2): 198–206. Bibcode:1976PhRvD..13..198P. doi:10.1103/PhysRevD.13.198.</ref>,所以熵至少可以产生到那个时候。据预测,宇宙中的一些大型黑洞在星系超级星系团的坍缩过程中会继续增长,最大可能达到10<sup>14</sup>M☉。即使是这些黑洞,也会在长达10<sup>106</sup>年的时间范围内消失<ref>Frautschi, Steven (13 August 1982). "Entropy in an Expanding Universe" (PDF). ''Science''. '''217''' (4560): 593–9. Bibcode:1982Sci...217..593F. doi:10.1126/science.217.4560.593. JSTOR 1688892. <nowiki>PMID 17817517</nowiki>. S2CID 27717447. <q>Since we have assumed a maximum scale of gravitational binding—for instance, superclusters of galaxies—black hole formation eventually comes to an end in our model, with masses of up to 10<sup>14</sup><var>M</var><sub>☉</sub> ... the timescale for black holes to radiate away all their energy ranges ... to 10<sup>106</sup> years for black holes of up to 10<sup>14</sup><var>M</var><sub>☉</sub></q></ref>。在那之后,宇宙就进入了所谓的黑暗时代,预计将主要由光子和轻子的稀薄气体组成<ref name=":0" />。由于只剩下非常分散的物质,宇宙的活动将急剧减少,能量水平极低,时间尺度极长。从推测上看,宇宙有可能进入第二个膨胀时代,或者假设目前的真空状态是假真空,那么真空可能会衰变为低能量状态<ref name=":0" />。也有可能,熵的产生将停止,宇宙将达到热寂<ref name=":0" /><nowiki>。另一个宇宙可能是由随机量子波动或量子隧道在大约[math]\displaystyle 10^{10^{10^{56}}}[/math]年内产生的</nowiki><ref>Carroll, Sean M.; Chen, Jennifer (October 2004). "Spontaneous Inflation and Origin of the Arrow of Time". Bibcode:2004hep.th...10270C</ref>。有人认为,在漫长的时间里,自发的熵减少最终会庞加莱递归定理<ref>Poincaré, Henri (1890). "Sur le problème des trois corps et les équations de la dynamique". ''Acta Mathematica''. '''13''': A3–A270.</ref>、热波动<ref>Tegmark, Max (2003). "Parallel Universes". ''Scientific American''. '''288''' (2003): 40–51. arXiv:astro-ph/0302131. Bibcode:2003SciAm.288e..40T. doi:10.1038/scientificamerican0503-40. <nowiki>PMID 12701329</nowiki>.</ref><ref>Tegmark, Max (May 2003). "Parallel Universes". ''Scientific American''. '''288''' (5): 40–51. arXiv:astro-ph/0302131. Bibcode:2003SciAm.288e..40T. doi:10.1038/scientificamerican0503-40<nowiki/>PMID 12701329</ref><ref>Werlang, T.; Ribeiro, G. A. P.; Rigolin, Gustavo (2013). "Interplay between quantum phase transitions and the behavior of quantum correlations at finite temperatures". ''International Journal of Modern Physics B''. '''27''' (1n03): 1345032. arXiv:1205.1046. Bibcode:2013IJMPB..2745032W. doi:10.1142/S021797921345032X. S2CID 119264198.</ref>、和波动定理<ref>Xiu-San Xing (1 November 2007). "Spontaneous entropy decrease and its statistical formula". arXiv:0710.4624 [cond-mat.stat-mech].</ref><ref>Linde, Andrei (2007). "Sinks in the landscape, Boltzmann brains and the cosmological constant problem". ''Journal of Cosmology and Astroparticle Physics''. '''2007''' (1): 022. arXiv:hep-th/0611043. Bibcode:2007JCAP...01..022L. CiteSeerX 10.1.1.266.8334. doi:10.1088/1475-7516/2007/01/022. S2CID 16984680.</ref>的作用下发生。然而,这种情况被描述为 "高度推测,很可能是错误的,[而且]完全无法测试。<ref>Pimbblet, Kevin (3 September 2015). "The fate of the universe: heat death, Big Rip or cosmic consciousness?". ''The Conversation''.</ref>"肖恩-M-卡罗尔最初是这种想法的倡导者,但现在不再支持它了<ref>Carroll, Sean (27 January 2014). ''Sean Carroll, "Fluctuations in de Sitter Space" FQXi conference 2014 in Vieques''. FQXi.</ref><ref>Boddy, Kimberly K.; Carroll, Sean M.; Pollack, Jason (2014). "De Sitter Space Without Dynamical Quantum Fluctuations". arXiv:1405.0298 [hep-th].</ref>。 |
| 2010年对熵状态的一份分析表明,"一般引力场的熵仍不为人所知","引力熵很难量化"。该分析考虑了估算所需的几种可能的假设,并且表明可观测宇宙的熵比之前想象的要多。这是因为分析的结论是:超大质量黑洞是最大的贡献者<ref>Egan, Chas A.; Lineweaver, Charles H. (2010). "A Larger Estimate of the Entropy of the Universe". ''The Astrophysical Journal'' (published 3 February 2010). '''710''' (2): 1825–34 [1826]. arXiv:0909.3983. Bibcode:2010ApJ...710.1825E. doi:10.1088/0004-637X/710/2/1825. S2CID 1274173.</ref>。李 · 斯莫林更进一步说:"人们早就知道,引力对于防止宇宙进入热平衡非常重要。引力束缚系统具有负的比热——也就是说,当能量消失时,其组分的速度会增加。...... 这样的系统不会演化到均匀的平衡状态。相反,随着它被分割成子系统,它会变得越来越结构化和异质化<ref>Smolin, Lee (2014). "Time, laws, and future of cosmology". ''Physics Today''. '''67''' (3): 38–43 [42]. Bibcode:2014PhT....67c..38S. doi:10.1063/pt.3.2310.</ref>。最近在一个相对简单的封闭系统中的非平衡稳态的实验发现,也支持了这一观点。 可以预期的是,一个被分割成子系统的孤立系统不一定能达到热力学平衡并保持在非平衡稳态。熵将从一个子系统传递到另一个子系统,但其产生量将为零,这与热力学第二定律并不矛盾<ref>Lemishko, Sergey S.; Lemishko, Alexander S. (2017). "Cu2+/Cu+ Redox Battery Utilizing Low-Potential External Heat for Recharge". ''The Journal of Physical Chemistry C'' (published 30 January 2017). '''121''' (6): 3234–3240. doi:10.1021/acs.jpcc.6b12317.</ref><ref>Lemishko, Sergey S.; Lemishko, Alexander S. (2020). "Non-equilibrium steady state in closed system with reversible reactions: Mechanism, kinetics and its possible application for energy conversion". ''Results in Chemistry'' (published 8 February 2020). '''2''': 100031. doi:10.1016/j.rechem.2020.100031.</ref>。 | | 2010年对熵状态的一份分析表明,"一般引力场的熵仍不为人所知","引力熵很难量化"。该分析考虑了估算所需的几种可能的假设,并且表明可观测宇宙的熵比之前想象的要多。这是因为分析的结论是:超大质量黑洞是最大的贡献者<ref>Egan, Chas A.; Lineweaver, Charles H. (2010). "A Larger Estimate of the Entropy of the Universe". ''The Astrophysical Journal'' (published 3 February 2010). '''710''' (2): 1825–34 [1826]. arXiv:0909.3983. Bibcode:2010ApJ...710.1825E. doi:10.1088/0004-637X/710/2/1825. S2CID 1274173.</ref>。李 · 斯莫林更进一步说:"人们早就知道,引力对于防止宇宙进入热平衡非常重要。引力束缚系统具有负的比热——也就是说,当能量消失时,其组分的速度会增加。...... 这样的系统不会演化到均匀的平衡状态。相反,随着它被分割成子系统,它会变得越来越结构化和异质化<ref>Smolin, Lee (2014). "Time, laws, and future of cosmology". ''Physics Today''. '''67''' (3): 38–43 [42]. Bibcode:2014PhT....67c..38S. doi:10.1063/pt.3.2310.</ref>。最近在一个相对简单的封闭系统中的非平衡稳态的实验发现,也支持了这一观点。 可以预期的是,一个被分割成子系统的孤立系统不一定能达到热力学平衡并保持在非平衡稳态。熵将从一个子系统传递到另一个子系统,但其产生量将为零,这与热力学第二定律并不矛盾<ref>Lemishko, Sergey S.; Lemishko, Alexander S. (2017). "Cu2+/Cu+ Redox Battery Utilizing Low-Potential External Heat for Recharge". ''The Journal of Physical Chemistry C'' (published 30 January 2017). '''121''' (6): 3234–3240. doi:10.1021/acs.jpcc.6b12317.</ref><ref>Lemishko, Sergey S.; Lemishko, Alexander S. (2020). "Non-equilibrium steady state in closed system with reversible reactions: Mechanism, kinetics and its possible application for energy conversion". ''Results in Chemistry'' (published 8 February 2020). '''2''': 100031. doi:10.1016/j.rechem.2020.100031.</ref>。 |