作业帮 > 英语 > 作业

英语翻译根据广义相对论,引力场将使时空弯曲.当恒星的体积很大时,它的引力场对时空几乎没什么影响,从恒星表面上某一点发的光

来源:学生作业帮 编辑:拍题作业网作业帮 分类:英语作业 时间:2024/05/01 00:16:49
英语翻译
根据广义相对论,引力场将使时空弯曲.当恒星的体积很大时,它的引力场对时空几乎没什么影响,从恒星表面上某一点发的光可以朝任何方向沿直线射出.而恒星的半径越小,它对周围的时空弯曲作用就越大,朝某些角度发出的光就将沿弯曲空间返回恒星表面.
等恒星的半径小到一特定值(天文学上叫“史瓦西半径”)时,就连垂直表面发射的光都被捕获了.到这时,恒星就变成了黑洞.说它“黑”,是指它就像宇宙中的无底洞,任何物质一旦掉进去,“似乎”就再不能逃出.实际上黑洞真正是“隐形”的.那么,黑洞是怎样形成的呢?其实,跟白矮星和中子星一样,黑洞很可能也是由恒星演化而来的.当一颗恒星衰老时,它的热核反应已经耗尽了中心的燃料(氢),由中心产生的能量已经不多了.这样,它再也没有足够的力量来承担起外壳巨大的重量.所以在外壳的重压之下,核心开始坍缩,直到最后形成体积小、密度大的星体,重新有能力与压力平衡.
质量小一些的恒星主要演化成白矮星,质量比较大的恒星则有可能形成中子星.而根据科学家的计算,中子星的总质量不能大于三倍太阳的质量.如果超过了这个值,那么将再没有什么力能与自身重力相抗衡了,从而引发另一次大坍缩.
这次,根据科学家的猜想,物质将不可阻挡地向着中心点进军,直至成为一个体积趋于零、密度趋向无限大的“点”.而当它的半径一旦收缩到一定程度(史瓦西半径),as I mention before,巨大的引力就使得即使光也无法向外射出,从而切断了恒星与外界的一切联系——“黑洞”诞生了.
与别的天体相比,黑洞是显得太特殊了.例如,黑洞有“隐身术”,人们无法直接观察到它,连科学家都只能对它内部结构提出各种猜想.那么,黑洞是怎么把自己隐藏起来的呢
Actually,are same with the white dwarf stars and the neutron stars,the black hole are formed from the gravitational collapse of stars,usually having a great,massive,core.When stars are getting senile,their thermonuclear reactions have exhausted the central fuel (Hydrogen).Thus,they do not have enough power to undertake the huge weight of their covering.Therefore,the gravitational pull the core of the star begin collapse,until they reform into the star of small mass and high density.The star are created when huge,gigantic; gas clouds bind together due to attractive forces and form a hot core,combined from all the energy of the two gas clouds.This energy produced is so great when it first collides,that a nuclear reaction occurs and the gases within the star start to burn continuously.² The Hydrogen is the dominant gas consumed in a star.The equilibrium achieved the star in order to avoid collapsing at this point.The gravitational pull from the core of the star is equal to the gravitational pull of the gases forming a type of orbit.² however; the star could get into various stages when this equality is destroyed.The stars of small in mass will evolution as the White Dwarf.If the stars are to have a larger mass,then it may possibly be a Supernova.A black hole is one of the last options that a star may take.If the core of a star is so massive (approximately 6-8 solar masses; one solar mass being equal to the sun’s mass) ²then it is most likely that when the star’s gases are almost consumed those gases will collapse inward,forced into the core by the gravitational force laid upon them.
Compare to other wonders in the galaxy,black holes are very mysterious and special,because of their ability to make themselves invisible,thus people are unable to observe them.Even scientists are only able to surmise what their internal structures are.In that way,how do black holes hide themselves?The answer is warped space and time.According to theory,light spread along a straight line,however,the time and space will be bending under the gravitational field.In that area,light still travel between any two points,but the pathway of the light is no longer horizontal,instead it becomes bended.In other word,light want to go in a straight line,yet strong gravitational forces are pulling the light to bend itself from the original direction.
According to the general theory of relativity,the gravitational field will cause cause the space and time to be bended.When the star’s volume is really big,its gravitational field nearly does not influence to the space and time.The light can travel along a straight line in any direction.In contract,the smaller radiuses of the star will suffer huge gravitational.The gravitational pull the light along the curved track returns to the surface of stars.When the star’s radii slight as a characteristic radius (in astronomy is called Schwarzschild radius as a specific value,sometimes historically referred to as the gravitational radius),the vertical superficial launch light will be caught.At this time,the stars become black holes.They are likely the bottomless pits in the universe,once falling into seem no able to escape.The huge gravitational the light unable outward to object,thus has cut off the relation between star and outside.Therefore,the black hole is becoming invisible.³