黑洞的调查报告
应科德的要求，我到黑洞去了一遭并活着回来了，特在此把调查报告公布。黑洞是根據現代的物理理論和天文學理論，所預言的在宇宙空間中存在的一種天體區域。
歷史上, 法國力學家拉普拉斯曾預言:「一個密度如地球, 而直徑為 250 個太陽的發光恆星, 由於其引力的作用, 將不允許任何光線離開它。由於這個原因, 宇宙中最大的發光天體, 卻不會被我們看見」。
黑洞是由一個質量相當大的天體，在核能耗盡死亡後發生引力塌縮後形成。根據牛頓萬有引力定理, 由於黑洞的第一宇宙速度過大, 連光也逃逸不出來, 故名黑洞.
在此區域內的萬有引力非常強大，任何物質都不可能從此區域內逃逸出去，甚至光線都被它強大的引力拉回，因此黑洞本身不會發光，不能用天文望遠鏡直接觀測到，是黑漆漆的天體，但天文學家可藉觀察黑洞周圍物質被吸引時的情況，找出黑洞位置。
尺寸和質量
質量達太陽10倍的黑洞之電腦模擬圖
質量達太陽10倍的黑洞之電腦模擬圖
黑洞是由大約大於太陽質量的3.2倍的天體發生引力坍塌後形成的（小於1.4個太陽質量的恆星，會變成白矮星）。天文學的觀測表明，在很多星系的中心，包括銀河系，都存在超過太陽質量上億倍的超大質量黑洞。
根據愛因斯坦的廣義相對論，黑洞是可以預測的。他們發生於史瓦茲度量。這是由卡爾•史瓦茲於1915年發現的愛因斯坦方程的最簡單解。
根據史瓦茲解，如果一個引力天體的半徑小於一個特定的值，天體將會發生坍塌，這個半徑就叫做史瓦茲半徑。在這個半徑以下的天體，其中的時空嚴重彎曲，從而使其發射的所有射線，無論是來自什麼方向的，都將被吸引入這個天體的中心。因為相對論指出任何物質都不可能超越光速，在史瓦茲半徑以下的天體的任何物質——包括引力天體的組成物質——都將塌陷於中心部分。一個有理論上無限密度組成的點組成引力奇點（gravitational singularity）。由於在史瓦茲半徑內連光線都不能逃出黑洞，所以一個典型的黑洞確實是“黑”的。
史瓦茲半徑由下面式子給出：
R_s = \frac{2GM}{c^2}
G是萬有引力常數，M是天體的質量，c是光速。對於一個與地球質量相等的天體，其史瓦茲半徑僅有9毫米。
特性
目前公認的理論認為，黑洞只有三個物理量有意義：質量、電荷、角動量。也就是說：對於一個黑洞，一旦這三個物理量確定下來了，這個黑洞的特性也就唯一確定了，這稱為黑洞的無毛定理，或者三毛定理。
分类
黑洞分類： 一、超巨質量黑洞 二、小質量黑洞 三、中型黑洞
超巨質量黑洞： 到目前為止可以所有已知星系中心發現其蹤跡。 它的質量據信是太陽的數百萬至十數億倍。 小質量黑洞：質量為太陽質量的１０至２０倍， 即超新星爆炸以後所留下的核心質量是 太陽的 3 ~ 15 倍就會形成黑洞。 而理論預測質量為太陽的 40 倍以上， 則可不經超新星爆炸過程而形成黑洞。 中型黑洞： 推論是由小質量黑洞合併形成， 最後則變成超巨質量黑洞，但中型黑洞是否真實存在仍然必需存疑。
微黑洞
微黑洞是理论预言的一类黑洞，目前尚无证据支持微黑洞的存在。它们诞生于宇宙大爆炸初期，质量非常小，根据霍金的理论，黑洞质量越小，“蒸发”越快。因此如果存在微黑洞，那么它们现在一定已经蒸发殆尽了。
否认黑洞存在的一些观点
1. 量子力学方面的反驳：黑洞中心的奇点具有量子不稳定性，所以整个黑洞不可能稳定存在。
2. 目前发现的黑洞是一些暗能量星：美国加利福尼亚劳伦斯·利弗莫尔国家实验室的天体物理学家乔治·钱普拉因等认为，目前发现的黑洞是一些暗能量星，真正意义上的黑洞是不存在的。
另外：Supermassive
Black Holes
The active galaxies appear to require a compact energy source of enormous strength. The most plausible candidate is a rotating, supermassive black hole of order a billion solar masses at their center. Until recently there has been strong circumstantial evidence to support such a mechanism. In the past few years evidence of much more direct nature has emerged.
Evidence for a Supermassive Black Hole in M87
The left portion of the following Hubble Space Telescope photograph shows the center of the giant elliptical galaxy M87, which is the 87th entry in the famous Messier Catalog. This galaxy is believed to contain a supermassive black hole of several billion solar masses at its center. The observations indicate that approximately 3 billion solar masses are concentrated in a region at the galactic core that is only about the size of the Solar System. The diagonal line across the right image is a jet of high-speed electrons approximately 6500 light years long that is probably being ejected from the galactic nucleus by the black hole located there.
The right side of the figure illustrates schematically Doppler shift measurements made on the central region of M87 that suggest rapid rotation of the matter near the center. The measurement was made by studying how the light from the disk is red shifted and blue shifted by the Doppler effect, using the Faint Object Spectrograph aboard the Hubble Space Telescope. Part of the swirling disk spins in Earth's direction and the other side spins away from Earth, thus causing opposite Doppler shifts. The gas on one side of the disk is moving away from Earth at a speed of about 550 kilometers per second (red shift). The gas on the other side of the disk is approaching the Earth at the same speed (blue shift).
This high velocity suggests a huge gravitational field at the center of M87, far larger than could be accounted for by the visible stars there. This is what would be expected for matter swirling around the supermassive black hole, with part of it falling forever into the black hole and part of it being ejected in the high-speed jet seen coming from the nucleus of M87. Here is a simulation of what gas swirling around a supermassive black hole in the core of a spiral galaxy might look like (Source).
Evidence for a Supermassive Black Hole in NGC4261
The following image shows a composite of ground based optical and radio telescope images of the galaxy NGC 4261, and a high resolution Hubble Space Telescope image of the core of this galaxy.
Click here for a more detailed description.
NGC 4261 has enormous jets shooting from its core and very strong radio frequency emission. It is thought that the jets are powered by a gargantuan black hole of perhaps a billion solar masses, and that the ring in the Hubble image is an accretion disk feeding the black hole. The black hole itself presumably lies inside the bright spot at the center. Even a billion solar mass black hole would be too small to see in this image, for as we see in the following table, it would only be the size of the solar system.
Radius for Black Hole of a Given Mass
Object Mass Black Hole Radius
Earth 5.98 x 1027 g 0.9 cm
Sun 1.989 x 1033 g 2.9 km
5 Solar Mass Star 9.945 x 1033 g 15 km
Galactic Core 109 Solar Masses 3 x 109 km
Velocities near the Center of M84
The following figure illustrates observations taken with the Hubble Space Telescope Imaging Spectrograph (Ref and Ref) of a region across the center of the galaxy M84, which is in the Virgo Cluster about 50 million light years away.
The right portion of the figure is a radial velocity distribution across the slice illustrated in the left portion of the figure, determined by looking at the Doppler shift of light coming from this region. As one approaches the nucleus (moving downward in the right image) there is a sudden blue shift, indicating rapid motion of the gas near the nucleus toward us. The Doppler shift indicates that the velocity toward us reaches as high as 400 km/s at a distance only 26 light years from the center. Then suddenly the sign of the radial velocity reverses and a redshift indicating similar velocities away from us is observed, with this red shift decreasing rapidly as one moves away from the center (toward the bottom of the right diagram).
The most obvious interpretation of these data is that there is a large rotating disk around the nucleus of M84 that we are seeing in cross section. Above the nucleus in this image the disk matter is moving toward us at 400 km/s, and below the nucleus the disk matter is moving away at similar velocities. The only simple explanation is that this is an accretion disk feeding a supermassive black hole in the center of M84, since no other explanation could easily account for gas velocities of these magnitudes near the center. Thus, we may take the "S" shape of such velocity distributions for galactic cores as telltale signs for an accretion disk around a supermassive black hole.
This black hole interpretation is strengthened by previously known information about this galaxy: its nucleus very active and emits jets of particles that are very strong radio sources. The observed radial velocities near the center suggest a mass of about 300 million solar masses for the black hole.
A Black Hole in the Sombrero Galaxy?
The image on the left is of the Sombrero Galaxy (M104). This galaxy is a strong X-Ray emitter, and unusually high velocities are observed for stars near its center; this raises speculation that it may have a black hole of approximately 1 billion solar masses at its core. Credit: T. Boroson (NOAO /USGP), W. Keel (UA), KPNO
Origin of Supermassive Black Holes
It is now believed that many galaxies have supermassive black holes at their centers, and that whether such galaxies are active galaxies is a question of whether mass is being fed into these black holes. The simplest ideas for the origin of such supermassive black holes are that they are conglomerations of many star-size black holes that were formed during the history of a galaxy, or perhaps that galaxies formed around large black holes that then grew by accreting matter. 科德让你去黑洞……
为什么不让你去地狱啊…… 少校辛苦。。。
那个。。。您能不能体谅下我们
英文就不要发了 他认识我，我不认识他呀~~~~~~ 动作好快。。。。。 另外有3/5的内容完全看不明白。。。。。 因为那写鸟文我懒得翻了 这调查报告写的……我也好想去看看啊……那个，英文的我看得如此头昏 少校好有耐心~~~ 你不够负责啊……那么不容易的送你去了一遭，你就带了一半的研究结果回来啊 恩 很好 很强大
不过 E文水平有限 麻烦LZ翻译下啊 高深.............. 好深奥...
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