For the Poincaré half-space model in dimension 2, the metric evaluates on the coordinate tangent vectors \(\frac{\partial}{\partial x}, \frac{\partial}{\partial y} \in T_pM\) as \[g_p\!\left(\frac{\partial}{\partial x^i}\bigg|_p,\;\frac{\partial}{\partial x^j}\bigg|_p\right) = \frac{1}{y^2}\,\delta_{ij},\] i.e. the coordinate tangent vectors are orthogonal and each has length \(\frac{1}{y}\) — shrinking to zero as \(p\) approaches the boundary \(y\to 0\), which is what makes the space “infinitely large” near the boundary.
(This is where the famous “but first, we will need to talk about parallel universes” quote comes from. In the SM64 community, covering spaces are known as “parallel universes”). Wheather intentional (like in Pacman) or unintentional (like in Super Mario 64, due to casting floating point numbers to short ints), it is often the case that walking in a straight line long enough will eventually lead you back to the same point.
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果实外形也有明显不同。蜡梅果实是坛状或倒卵状椭圆形，种子藏在果实里，果实剥开后，内部种子乍看之下像红豆。而梅花的果实是近球形，有缝合线，被柔毛。
集团 CEO Carlos Alberini 曾指出，过去几年美国与亚洲市场的门店及官网客流持续下滑，如今欧洲也出现类似趋势。财报显示，大中华区业务长期承压，公司已采取裁员与关店措施，并寻求授权合作伙伴接管相关业务。