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1.
研究了黑洞形成过程中的熵演化,确立了一个基本观点,那就是确认引力場是将无序化星云转变成有序化黑洞的唯一的基本因素,而贝克斯坦-霍金熵正是引力场在形成有序化黑洞的过程中,黑洞向黑洞外抛射的无序化量子气态物质的熵,它已应不再属于黑洞的熵.因此,黑洞的熵应是黑洞抛射量子气态物质的熵之后的剩余熵.  相似文献   

2.
将星系中黑洞的形成过程分为两个阶段:第一个阶段是有序化的"整肃"阶段,第二个阶段是无序化的"撞击"阶段.从热力学角度和引力场论、量子辐射的角度详细地分析了这两个阶段中星系系统熵(黑洞广义熵)的演化,得出星系中黑洞的形成过程是一个熵减少过程的结论.  相似文献   

3.
将正、负能谱中黑洞能力学理分别应用于分析Schwarzchild(SW)黑洞.Kerr-Neuman(K-N)黑洞以及Sen黑洞的熵及其演化过程,对它们的对照分析结果表明:负能谱热力学对表征黑洞的熵及其演化规律和极限特征比Bekenstein热力学优越得多.  相似文献   

4.
根据LandauLD的负能谱论述,论证了高密度自引力系统是实际存在的负能谱系统,进一步以负能谱理论研讨了黑洞的视界温度、熵以及熵的演化.最后,讨论了黑洞的热力学第三定律.  相似文献   

5.
分别在薄盘和厚盘两种情况下,详细讨论了纯吸积过程和B-Z过程中吸积盘中心黑洞的熵变.结果表明,中心黑洞各参量在B-Z过程中的变化率与在纯吸积过程中的变化率之差与盘结构无关,而且与B-Z过程的辐射功率成正比.在B-Z过程中黑洞熵的变化率总是大于纯吸积过程中黑洞熵的变化率,二者之差来自中心黑洞延伸视界上的耗散功率.此外,还讨论了黑洞热力学定律在上述盘吸积过程中的有效性.  相似文献   

6.
分别在薄盘和厚盘两种情况下,详细讨论了纯吸积过程和B-Z过程中吸积盘中心黑洞的熵变。结果表明,中心黑洞各参量在B-Z过程中的变化率与在纯吸积过程中的变化率之差与盘结构无关,而且与B-Z过程的辐射功率成正比。在B-Z过程中黑洞熵的变化率总是大于纯吸积过程中黑洞熵的变化率,二者之差来自中心黑洞延伸视界上的耗散功率。此外,还讨论了黑洞热力学定律在上述盘吸积过程中的有效性。  相似文献   

7.
利用广义不确定原理,研究了Kerr黑洞热力学的量子修正.根据视界附近粒子的量子不确定性,给出了黑洞温度与黑洞视界半径的关系式.分析这一关系式,给出了Kerr黑洞的临界状态和临界参量.根据黑洞热力学第一定律,对Kerr黑洞热容和黑洞熵进行了计算.利用黑洞热容公式,给出了黑洞的剩余状态.结果表明,Kerr黑洞剩余状态与临界状态等价,广义不确定原理可避免黑洞蒸发过程中温度奇异性的出现.得到的黑洞熵具有包括对数修正在内的量子修正项.  相似文献   

8.
广义不确定原理对一般静态黑洞熵的影响   总被引:1,自引:0,他引:1  
把广义不确定原理引入黑洞熵的计算,采用薄膜brick-wall模型,对一般静态黑洞外部标量场的熵进行了计算,得到了熵计算公式.应用该公式结果表明,可以得到已知所有静态黑洞的Bekenstein-Hawking熵.作为比较和进一步研究,对视界面上的二维膜的熵进行计算,可以更方便和一般性地得到熵与视界面积成正比的结论,该讨论可直接表明黑洞熵就是其视界面上的量子态的熵.与原始brick-wall模型不同的是,这一结论是有限的,计算中无需引入截断,且小质量近似也可以避免.  相似文献   

9.
利用李立新和刘辽导出的黑洞视界附近的辐射态方程计算了约束在一个球盒形子中的自引力辐射体系(含有中心黑洞)的熵的上限,讨论了该体系的引力坍缩的合理模式,证明了这一坍缩过程是一个熵增加过程;在坍缩过程中,整个体系的熵的上限等于具有相同质量的黑洞熵,这一结果为黑洞熵的起源提供了一个合理的解释。  相似文献   

10.
基于广义熵原理的生态系统演化动力学   总被引:1,自引:0,他引:1  
生态系统作为由大量组元组成的典型复杂开放系统.其演化动力学是当前学术界的研究热点和难点.本文定义了生态系统的"广义熵",指出控制生态系统演化动力学的物理学法则是"最大广义熵原理",即系统总是寻找一种优化过程使得在给定的约束或代价下广义熵最大,即总是使自身得到最大限度的发展.基于此原理导出了有序结构形成和演化的基本方程,并结合植被生态系统的案例数值模拟了有序结构形成和演化的动力学过程,由此形成了研究具体生态系统演化动力学的新方法.新方法的提出也为解决一般化的生态系统演化问题提供了从机理到具体置化分析的完整框架.  相似文献   

11.
Di Matteo T  Springel V  Hernquist L 《Nature》2005,433(7026):604-607
In the early Universe, while galaxies were still forming, black holes as massive as a billion solar masses powered quasars. Supermassive black holes are found at the centres of most galaxies today, where their masses are related to the velocity dispersions of stars in their host galaxies and hence to the mass of the central bulge of the galaxy. This suggests a link between the growth of the black holes and their host galaxies, which has indeed been assumed for a number of years. But the origin of the observed relation between black hole mass and stellar velocity dispersion, and its connection with the evolution of galaxies, have remained unclear. Here we report simulations that simultaneously follow star formation and the growth of black holes during galaxy-galaxy collisions. We find that, in addition to generating a burst of star formation, a merger leads to strong inflows that feed gas to the supermassive black hole and thereby power the quasar. The energy released by the quasar expels enough gas to quench both star formation and further black hole growth. This determines the lifetime of the quasar phase (approaching 100 million years) and explains the relationship between the black hole mass and the stellar velocity dispersion.  相似文献   

12.
The formation of the first massive objects in the infant Universe remains impossible to observe directly and yet it sets the stage for the subsequent evolution of galaxies. Although some black holes with masses more than 10(9) times that of the Sun have been detected in luminous quasars less than one billion years after the Big Bang, these individual extreme objects have limited utility in constraining the channels of formation of the earliest black holes; this is because the initial conditions of black hole seed properties are quickly erased during the growth process. Here we report a measurement of the amount of black hole growth in galaxies at redshift z = 6-8 (0.95-0.7 billion years after the Big Bang), based on optimally stacked, archival X-ray observations. Our results imply that black holes grow in tandem with their host galaxies throughout cosmic history, starting from the earliest times. We find that most copiously accreting black holes at these epochs are buried in significant amounts of gas and dust that absorb most radiation except for the highest-energy X-rays. This suggests that black holes grew significantly more during these early bursts than was previously thought, but because of the obscuration of their ultraviolet emission they did not contribute to the re-ionization of the Universe.  相似文献   

13.
李华润 《江西科学》2008,26(6):844-847
本文利用基于贝肯斯坦(Bekenstein)熵边界假设的最小面积方法求解Anti-de-Sitter黑洞熵。在此方法中黑洞熵和辐射或吸收粒子的能量-动量(色散)关系有很密切联系,从而可以通过修正的色散关系而得到对黑洞熵的修正。本文讨论了2种修正色散关系对Anti-de-Sitter黑洞熵的影响。第1种色散关系的修正项与普朗克能标呈线性关系,结果得到的黑洞熵的主要修正项与视界面积的方根成正比,而另一种修正色散关系含有普朗克能标的平方项,所求得的黑洞熵的主要修正项是视界面积的对数形式,这个结果与其它通过量子引力途径得到的结果相吻合。  相似文献   

14.
Stellar-mass black holes are found in X-ray-emitting binary systems, where their mass can be determined from the dynamics of their companion stars. Models of stellar evolution have difficulty producing black holes in close binaries with masses more than ten times that of the Sun (>10; ref. 4), which is consistent with the fact that the most massive stellar black holes known so far all have masses within one standard deviation of 10. Here we report a mass of (15.65 +/- 1.45) for the black hole in the recently discovered system M 33 X-7, which is located in the nearby galaxy Messier 33 (M 33) and is the only known black hole that is in an eclipsing binary. To produce such a massive black hole, the progenitor star must have retained much of its outer envelope until after helium fusion in the core was completed. On the other hand, in order for the black hole to be in its present 3.45-day orbit about its (70.0 +/- 6.9) companion, there must have been a 'common envelope' phase of evolution in which a significant amount of mass was lost from the system. We find that the common envelope phase could not have occurred in M 33 X-7 unless the amount of mass lost from the progenitor during its evolution was an order of magnitude less than what is usually assumed in evolutionary models of massive stars.  相似文献   

15.
Detailed high-resolution observations of the innermost regions of nearby galaxies have revealed the presence of supermassive black holes. These black holes may interact with their host galaxies by means of 'feedback' in the form of energy and material jets; this feedback affects the evolution of the host and gives rise to observed relations between the black hole and the host. Here we report observations of the ultraviolet emissions of massive early-type galaxies. We derive an empirical relation for a critical black-hole mass (as a function of velocity dispersion) above which the outflows from these black holes suppress star formation in their hosts by heating and expelling all available cold gas. Supermassive black holes are negligible in mass compared to their hosts but nevertheless seem to play a critical role in the star formation history of galaxies.  相似文献   

16.
本文在文献[1]、[2]的基础上,应用相对论性牛顿万有引力定律,对原初典型恒星及其星核M。黑洞的形成、演化和结构,作了更深入的探索研究.得到了一系列很有意义的结果:1、导出了原初典型恒星Mo及其星核Ms黑洞质量的上界和下界.进而导出了原初典型恒星在其简并中子黑涧(Mos=Mo)态下一分为二的死亡大爆炸中释放能量的上下界(即超新星爆发所释放能量的上下界);2、导出了星核Ms黑洞独有的一系列鼎级极限物理特性.导出了黑洞无内阻理想流体的超流效应及黑洞吸集粒子的经纬分流的筛选效应.证明了星核Ms黑洞是具有不再爆炸、不再坍缩、不再发射的“三不”特性的稳定天体;3、在相对论性引力理论框架内,证明了光速最大原理;4、导出了原初典型恒星在一分为二的死亡大爆炸中静质量Mo、场(暗)质量△MG的结构和分布规律.揭示了星核Ms黑洞结构的奥秘;5、导出了恒星、星系、总星系等典型层次天体的真空中场(暗)质量的分布规律.  相似文献   

17.
概括了近年来极端黑洞热力学研究的主要结果,面临的挑战以及一些解决方案,在对极端黑洞的热力学和几何性质进行深入研究后,指出自然界中存在两种拓扑性质完全不同的极端黑洞,一种是Hawking提出的具有极端拓扑的极端黑洞,它的熵是零,另一种极端黑洞保留了非极端黑洞的拓扑,它的熵仍然可用Bekenstein-Hawking公式描述,此结论解决了近年来极端黑洞研究中Hawking学派和弦理论家之间的矛盾,解决了Hawking学派和黑洞相变理论的矛盾。  相似文献   

18.
Fabbiano G  Wang J  Elvis M  Risaliti G 《Nature》2011,477(7365):431-434
The current picture of galaxy evolution advocates co-evolution of galaxies and their nuclear massive black holes, through accretion and galactic merging. Pairs of quasars, each with a massive black hole at the centre of its galaxy, have separations of 6,000 to 300,000 light years (refs 2 and 3; 1 parsec = 3.26 light years) and exemplify the first stages of this gravitational interaction. The final stages of the black-hole merging process, through binary black holes and final collapse into a single black hole with gravitational wave emission, are consistent with the sub-light-year separation inferred from the optical spectra and light-variability of two such quasars. The double active nuclei of a few nearby galaxies with disrupted morphology and intense star formation (such as NGC 6240 with a separation of about 2,600 light years and Mrk 463 with a separation of about 13,000 light years between the nuclei) demonstrate the importance of major mergers of equal-mass spiral galaxies in this evolution; such mergers lead to an elliptical galaxy, as in the case of the double-radio-nucleus elliptical galaxy 0402+379 (with a separation of about 24 light years between the nuclei). Minor mergers of a spiral galaxy with a smaller companion should be a more common occurrence, evolving into spiral galaxies with active massive black-hole pairs, but have hitherto not been seen. Here we report the presence of two active massive black holes, separated by about 490 light years, in the Seyfert galaxy NGC 3393 (50 Mpc, about 160 million light years). The regular spiral morphology and predominantly old circum-nuclear stellar population of this galaxy, and the closeness of the black holes embedded in the bulge, provide a hitherto missing observational point to the study of galaxy/black hole evolution. Comparison of our observations with current theoretical models of mergers suggests that they are the result of minor merger evolution.  相似文献   

19.
在冷暗物质晕等级成团宇宙学模型中,伴随着暗物质晕并合,星系中心黑洞也断地并合和增长.于展Press-Schechter公式(EPS)我们编写了一自适应时间长Monte Carlo程序,重构了表征暗物质晕等级成团并合树.在成功地建立了黑洞和暗物质晕宇宙学演化模型后,我们通过引入直接吸积(包标准薄盘吸积和磁流体力学吸积)和随吸积两类黑洞吸积模式,论了黑洞自旋和质量宇宙学演化.通过与观测到AGN光度函数比较,我们发现黑洞通过磁流体力学吸积模式增长,与观测符合最好.于以上理论框架,我们还研究了双大质量黑洞演化,发现双黑洞通过共转气体吸积盘吸积对双黑洞质量比分存在显著影响.  相似文献   

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