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What do we really mean by 'near' and 'far'?
“近”和“远”的真正含义是什么?
In a way, distance is just a measure of how hard it is to get between two points.
在某种程度上，距离只是衡量到达某点难易程度的一种方法。
The harder to get from here to there, the more distant 'there' is. This makes thinking about distance in multiple dimensions easy.
到达某个地方越难，其距离就越远。这使得我们在多维度时空中思考距离变得简单。
In two spatial dimensions, a point a mile north and a mile east is more distant than one that's just a mile east - it's harder to get to.
在二维空间中，向东走一英里，再向北走一英里，肯定比只向东走一英里走得远——所以前者比后者更难到达。
What about one space and one time dimension? Piece of cake!
那在一维空间和一维时间中呢？很容易！
Getting to a point a mile east in 10 minutes is a lot harder than getting there in a day,
在10分钟内往东走到一英里远的地方，比在一天内走到那里难多了，
-so one mile east and 10 minutes in the future is way more distant than 1 mile east and a day in the future.
所以，距离现在一分钟和一英里的点比距离现在一天和一英里的点要远。
And a point that's a mile east right now is impossible to get to - so it's super distant!
同一时刻距离一英里的点不可能到达——所以它非常遥远！
But hold on - that would mean that 10 minutes is farther away than 10 hours! Doesn't that seem backwards?
但等等——那将意味着10分钟比10小时更远！这不是搞反了吗？
It kind of is - but it's the way the universe works: in special relativity, more time equals less distance! So distance in time is negative!
确实是——但这就是宇宙运行的方式：在狭义相对论中，更多的时间等于更少的距离！所以时间维度上的距离是负的！
And if you travel east and into the future in such a way that the negative time and positive space distances cancel out, your total distance will be zero.
如果你以这种方式向东走向未来，时间的距离和空间的距离相抵消，你移动的总距离将会是零。
And you'll be traveling at the speed of light! So how far away is tomorrow? It's closer than you think.
你将以光速行走！所以明天还有多远？没你想的那么远。
