手机浏览器扫描二维码访问
〃Yes。。。〃
〃So;〃 Ted said; 〃space is curved by gravity。〃
〃Okay。〃
〃And that means that you can think of gravity as nothing more than the curvature of space。 The Earth has gravity because the Earth curves the space around it。〃
〃Okay。〃
〃Except its not that simple;〃 Ted said。
Norman sighed。 〃I didnt think it would be。〃
Harry came back into the room; looked at the fruit on the table; but said nothing。
〃Now;〃 Ted said; 〃when you roll your ball bearing across the bowl; you notice that it not only spirals down; but it also goes faster; right?〃
〃Yes。〃
〃Now; when an object goes faster; time on that object passes slower。 Einstein proved that early in the century。 What it means is that you can think of the curvature of space as also representing a curvature of time。 The deeper the curve in the bowl; the slower time passes。〃
Harry said; 〃Well 。。。〃
〃Laymans terms;〃 Ted said。 〃Give the guy a break。〃
〃Yeah;〃 Norman said; 〃give the guy a break。〃
Ted held up the bowl。 〃Now; if youre doing all this mathematically; what you find is that the curved bowl is neither space nor time; but the bination of both; which is called''87'' space…time。 This bowl is space…time; and objects moving on it are moving in space…time。 We dont think about movement that way; but thats really whats happening。〃
〃It is?〃
〃Sure。 Take baseball。〃
〃Idiot game;〃 Harry said。 〃I hate games。〃
〃You know baseball?〃 Ted said to Norman。
〃Yes;〃 Norman said。
〃Okay。 Imagine the batter hits a line drive to the center fielder。 The ball goes almost straight out and takes; say; half a second。〃
〃Right。〃
〃Now imagine the batter hits a high pop fly to the same center fielder。 This time the ball goes way up in the air; and it takes six seconds before the center fielder catches it。〃
〃Okay。〃
〃Now; the paths of the two balls…the line drive and the pop fly…look very different to us。 But both these balls moved exactly the same in space…time。〃
〃No;〃 Norman said。
〃Yes;〃 Ted said。 〃And in a way; you already know it。 Suppose I ask you to hit a high pop fly to the center fielder; but to make it reach the fielder in half a second instead of six seconds。〃
〃Thats impossible;〃 Norman said。
〃Why? Just hit the pop fly harder。〃
〃If I hit it harder; it will go higher and end up taking longer。〃
〃Okay; then hit a low line drive that takes six seconds to reach center field。〃
〃I cant do that; either。〃
〃Right;〃 Ted said。 〃So what you are telling me is that you cant make the ball do anything you want。 There is a fixed relationship governing the path of the ball through space and time。〃
〃Sure。 Because the Earth has gravity。〃
〃Yes;〃 Ted said; 〃and weve already agreed that gravity is a curvature of space…time; like the curve of this bowl。 Any baseball on Earth must move along the same curve of ''88'' space…time; as this ball bearing moves along this bowl。 Look。〃 He put the orange back in the bowl。 〃Heres the Earth。〃 He put two fingers on opposite sides of the orange。 〃Heres batter and fielder。 Now; roll the ball bearing from one finger to the other; and youll find you have to acmodate the curve of the bowl。 Either you flick the ball lightly and it will roll close to the orange; or you can give it a big flick and it will go way up the side of the bowl; before falling down again to the other side。 But you cant make this ball bearing do anything you want; because the ball bearing is moving along the curved bowl。 And thats what your baseball is really doing…its moving on curved space…time。〃
Norman said; 〃I sort of get it。 But what does this have to do with time travel?〃
〃Well; we think the gravitational field of the Earth is strong…it hurts us when we fall down…but in reality its very weak。 Its almost nonexistent。 So space…time around the Earth isnt very curved。 Space…time is much more curved around the sun。 And in other parts of the universe; its very curved; producing a sort of roller…coaster ride; and all sorts of distortions of time may occur。 In fact; if you consider a black hole…〃
He broke off。
〃Yes; Ted? A black hole?〃
〃Oh my God;〃 Ted said softly。
月落参横 大漠敦煌 放个恋爱假 韩流逆时代 誓不为妃 谁是谁的灰太狼 豪门第一长媳 当时明月在 赌坊恩仇 风月债 绝尘山庄 罪之花 中国远征军史 升仙秘录 新汉艳史 萌侠之金兰结义(上) 天人记 出嫁不从夫1.2 异世之邪龙游香海 浪漫的倾心
本书又名你是我戒不掉的甜秦南御第一次遇见纪微甜,丢了重要信息。秦南御第二次遇见纪微甜,丢了相亲对象。秦南御第三次遇见纪微甜,丢了人如果有人问他,最厌恶的异性类型是什么样的,他会毫不犹...
他并非凡夫肉眼,他的眼光震惊世人! 1984年,他便投资创建了思科,而在随后的岁月里,他又先后创建了网景,亚马逊,雅虎 甚至是Google,ICQ...
...
...
本文无cp文案我变绿了,也变强了。 已有完结文青诡记事,孔方世界。 谢谢大家的支持,让我们做言情界的泥石流吧!...
刚发现自己会被裴聿城的意识附身时,林烟是拒绝的。明明在酒吧蹦迪,一醒来,躺在了荒郊野岭。明明在家里打游戏,一醒来,站在了欧洲大街。明明在跟男神烛光晚餐,一醒来,站在了男洗手间。这日子没法过了!后来的林烟大佬求上身,帮我写个作业!大佬求上身帮我考个试!大佬求上身,帮我追个男神!大佬听说生孩子挺疼...