2. The past and future are equally real.
2.过去与未来都是真实的。
This isn’t completely accepted, but it should be. Intuitively we think that the “now” is real, while the past is fixed and in the books, and the future hasn’t yet occurred. But physics teaches us something remarkable: every event in the past and future is implicit in the current moment. This is hard to see in our everyday lives, since we’re nowhere close to knowing everything about the universe at any moment, nor will we ever be — but the equations don’t lie. As Einstein put it, “It appears therefore more natural to think of physical reality as a four dimensional existence, instead of, as hitherto, the evolution of a three dimensional existence.”
并不是所有人都接受这个观点，但是大家应该接受。凭直觉，我们认为“现在”是真实的，“过去”只存在于书中，而“未来”尚未发生。但物理学告诉我们一个惊人的事实：过去与未来的每一刻都存在于当下。在我们的日常生活中要理解这一点很难，因为我们无从知晓宇宙中每一刻所发生的全部事件——但是数学方程可不会说谎。就像爱因斯坦说的：“长久以来，我们都把物质世界看成是一个不断发展的三维存在，但将它看成一个四维存在似乎更为自然一些。”