※ 引述《lpbrother (LP哥(LP = Love & Peace))》之铭言
: 刚看到老高讨论重力的影片
: 不知道哪些是对的哪些有争议，
我以前有唸书时有辅修声学，那时候顺便恶补了一下物理，当时觉得老高那集怪怪的，但
是只是就呆呆的看下去，喝完酒就躺着到明天
其实维基百科有很清楚的解释，看着顺一下脑袋
https://en.wikipedia.org/wiki/Special_relativity
爱因斯坦认同Minkowski用洛伦兹变换说明空间本身的对称性
Special relativity is restricted to the flat spacetime known as Minkowski space.
As long as the universe can be modeled as a pseudo-Riemannian manifold, a Loren
tz-invariant frame that abides by special relativity can be defined for a suffic
iently small neighborhood of each point in this curved spacetime.
In special relativity, however, the interweaving of spatial and temporal coordin
ates generates the concept of an invariant interval, denoted as
但是这里可以发现一个非欧几何空间的不变量
(Δs)2=c2(Δt)2 [(Δx)2+(Δy)2+(Δz)2
它是一个
1. 空间的旋转矩阵
2. 距离本身不被座标转动影响
https://upload.cc/i1/2022/01/06/3oDr65.jpg
https://upload.cc/i1/2022/01/06/NtunD2.jpg
Special relativity uses a flat 4-dimensional Minkowski space – an example of
a spacetime.
计算上，它比欧几里德空间多了一个维度如下
Minkowski spacetime appears to be very similar to the standard 3-di
mensional Euclidean space, but there is a crucial difference with respect to tim
e.
In 3D space, the differential of distance (line element) ds is defined by
{\displaystyle ds^{2}=d\mathbf {x} \cdot d\mathbf {x} =dx_{1}^{2}+dx_{2}^{2}+dx_
{3}^{2},} ds^2 = d\mathbf{x} \cdot d\mathbf{x} = dx_1^2 + dx_2^2 + dx_3^2,
where dx = (dx1, dx2, dx3) are the differentials of the three spatial dimensions
. In Minkowski geometry, there is an extra dimension with coordinate X0 derived
from time, such that the distance differential fulfills
{\displaystyle ds^{2}=-dX_{0}^{2}+dX_{1}^{2}+dX_{2}^{2}+dX_{3}^{2},}
where dX = (dX0, dX1, dX2, dX3) are the differentials of the four spacetime dime
nsions.
然后这些4维非欧不平直的空间，它对比我们日常经验的欧几里德空间，有什么真实的意义
呢。爱因斯坦发现这是反映重力的表现，然后就继续补他的
相对
论
老高可能没看维基百科