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→Quantum theory and violation of particle number conservation 量子理论与粒子数守恒的违背
It is possible to write down relativistic [[wikipedia:Quantum_Boltzmann_equation|quantum Boltzmann equations]] for [[wikipedia:Quantum_field_theory|relativistic]] quantum systems in which the number of particles is not conserved in collisions. This has several applications in [[wikipedia:Physical_cosmology|physical cosmology]],<ref name="KolbTurner">{{cite book|author1=Edward Kolb|author2=Michael Turner|name-list-style=amp|title=The Early Universe|year=1990|publisher=Westview Press|isbn=9780201626742}}</ref> including the formation of the light elements in [[wikipedia:Big_Bang_nucleosynthesis|Big Bang nucleosynthesis]], the production of [[wikipedia:Dark_matter|dark matter]] and [[wikipedia:Baryogenesis|baryogenesis]]. It is not a priori clear that the state of a quantum system can be characterized by a classical phase space density ''f''. However, for a wide class of applications a well-defined generalization of ''f'' exists which is the solution of an effective Boltzmann equation that can be derived from first principles of [[wikipedia:Quantum_field_theory|quantum field theory]].<ref name="BEfromQFT">M. Drewes; C. Weniger; S. Mendizabal (8 January 2013). "The Boltzmann equation from quantum field theory". ''Phys. Lett. B''. 718 (3): 1119–1124. arXiv:1202.1301. Bibcode:2013PhLB..718.1119D. doi:10.1016/j.physletb.2012.11.046. S2CID 119253828.</ref>
It is possible to write down relativistic [[wikipedia:Quantum_Boltzmann_equation|quantum Boltzmann equations]] for [[wikipedia:Quantum_field_theory|relativistic]] quantum systems in which the number of particles is not conserved in collisions. This has several applications in [[wikipedia:Physical_cosmology|physical cosmology]],<ref name="KolbTurner">{{cite book|author1=Edward Kolb|author2=Michael Turner|name-list-style=amp|title=The Early Universe|year=1990|publisher=Westview Press|isbn=9780201626742}}</ref> including the formation of the light elements in [[wikipedia:Big_Bang_nucleosynthesis|Big Bang nucleosynthesis]], the production of [[wikipedia:Dark_matter|dark matter]] and [[wikipedia:Baryogenesis|baryogenesis]]. It is not a priori clear that the state of a quantum system can be characterized by a classical phase space density ''f''. However, for a wide class of applications a well-defined generalization of ''f'' exists which is the solution of an effective Boltzmann equation that can be derived from first principles of [[wikipedia:Quantum_field_theory|quantum field theory]].<ref name="BEfromQFT">M. Drewes; C. Weniger; S. Mendizabal (8 January 2013). "The Boltzmann equation from quantum field theory". ''Phys. Lett. B''. 718 (3): 1119–1124. arXiv:1202.1301. Bibcode:2013PhLB..718.1119D. doi:10.1016/j.physletb.2012.11.046. S2CID 119253828.</ref>
对于碰撞中粒子数不守恒的相对论量子系统，给出相对论量子玻尔兹曼方程是可能的。这在物理宇宙学中有一些应用<ref name="KolbTurner" />，包括大爆炸核合成中轻元素的形成，暗物质的产生和重子发生。我们并不预先知道量子系统的状态可以用经典相空间密度''f'' 来表征。然而，对于许多应用来说，定义良好的''f'' 作为有效玻尔兹曼方程的解是存在的，可以由[[wikipedia:Quantum_field_theory|量子场论 Quantum_field_theory]]的第一原理推导得出。
对于碰撞中粒子数不守恒的相对论量子系统，给出相对论量子玻尔兹曼方程是可能的。这在物理宇宙学中有一些应用<ref name="KolbTurner" />，包括大爆炸核合成中轻元素的形成，暗物质的产生和重子发生。我们并不预先知道量子系统的状态可以用经典相空间密度''f'' 来表征。然而，对于许多应用来说，定义良好的''f'' 作为有效玻尔兹曼方程的解是存在的，可以由[[wikipedia:Quantum_field_theory|量子场论 Quantum_Field_Theory]]的第一原理推导得出。
===General relativity and astronomy 广义相对论和天文学===
===General relativity and astronomy 广义相对论和天文学===