#9 journal

Fri Jun 9 07:47 AM GMT+7

Wuhan 27°C  Mostly Sunny  H: 35°C  L:23°C

突然想非一下，记录一下我一瞬间的想法💡：

在牛顿的时空观里，他认为时间是均匀的，在其1687年发表的《自然哲学的数学原理》一书中对时间给出了如下定义：“绝对的、真实的数学的时间，就其自身及其本质而言，是永远均匀流动的，它不依赖于任何外界事物”。

但爱因斯坦发现的狭义与广义相对论的一个重要结论就是时间的流逝不是均匀的。狭义相对论认为相对运动的物体的时间的流逝要比相对静止的物体的时间流逝的慢。而广义相对论认为离引力源越近，时间流逝的越慢（待会儿附上解释）。

我想说当然啊，都用不着爱因斯坦出马，LHY不就行啦，毕竟我明明就感觉time stretches and contracts depending on her presence. 所以时间当然不均匀啊，牛顿啊牛顿，草率了啊🤪

FYI, here's some useful explanations in terms of "time stretches and contracts" as I just mentioned, in fact, we name that phenomenon as Time dilation.

Time dilation is the difference in elapsed time as measured by two clocks, either due to a relative velocity between them (special relativity) or due to a difference in gravitational potential between their locations (general relativity). When unspecified, "time dilation" usually refers to the effect due to velocity.

So how do we calculate them?

Time dilation calculated due to a relative velocity (special relativity):

Time dilation calculated due to gravitational potential (general relativity):

所以因为相对速度（relative velocity）的存在，时间会流逝的不一样；重力势能的不同（difference in gravitational potential），时间也会不一样。So basically, we're all in different time zone, 只属于我们自己的time zone, although that time dilation can be neglected. 我们表面上都遵守着格林威治时间，但其实每一个人都有自己独一无二的时钟。像极了我的notion, the concept of destiny is mesmerising, 比如童话般的有些人注定相遇，命运使我们踏上同一趟旅途这样的想法，but what's even more alluring is that how we're not totally under the spell of destiny. Yeh maybe I'm bound to fall for you, maybe we're bound to struggle, sure, so what? Fate, don't you dare tell me the ending? You can't. 就跟格林威治时间一样，我们以为我们遵守着同一个不可被否定的事实，事实上不是。我就是双标，如果深得我意那没事儿 if they spoil us an unsatisfactory one, we'll tell them otherwise. 不管是情感还是人生。

“Some birds are not meant to be caged, that's all. Their feathers are too bright, their songs too sweet and wild. So you let them go, or when you open the cage to feed them they somehow fly out past you. And the part of you that knows it was wrong to imprison them in the first place rejoices, but still, the place where you live is that much more drab and empty for their departure.”
― Stephen King, Rita Hayworth and Shawshank Redemption

不只是"some birds"啦，no birds are meant to be caged. So just trust your gut feelings，其他咩都唔重要架喇。

想说给你听一段话：

在你拍月亮或者日落的时候，你会发现拍出来的并没有真实看到的美，但你不会认为是天空不好看，因为你知道相机不能捕捉天空的美，你应该以同样的方式去看待自己，事实是，你和晚霞一样耀眼。

李皓欣，或许在我眼里月亮也因你暗淡，但抛去滤镜不谈，你和晚霞一样耀眼是一定没错啦。

有些人只通过相机看就以为那是真实的你，有些人虽然透过相机看却知道那不是全部的你，还有些人舍弃相机真正地看到你。我不敢说完全理解你，毕竟我们在不同年份出生，有着不同的家庭背景，接受着不尽相同的教育，成长在截然不同的环境，我们经历的事情也不是一模一样，性格不同，喜好不同，口味不同，你在工作，我在上学······我们有太多不同，怎么能说完全理解你，但好在起码我知道你值得更好的，最好的。I know it's okay to not be okay. But eventually you deserve to be happy, really happy, dancing on air happy (yea I still remember parts of the quote from one of your favourites "Love, Rosie"). It might take some time, but something good will happen in the end.

最后 some fun facts about general relativity attached below: