All points on the surface of a sphere are equally distant from the center.

球心到球上任何一点距离都一。

That's also of great value scientifically.

这个外球区域科学研究意义很大。

The research was based on pulsar timing observations carried out with the Five-hundred-meter Aperture Spherical Telescope (FAST).

这项研究是基于500米口径球望远(FAST)进行脉冲星计时观测。

To prove the theorem we shall suppose that the graph G is drawn on a sphere as described above.

为了证明这个定理，我们假定这个圆G能按上述方式画在一个球上。

So, the electric flux is independent of the  radius of the concentric spherical surface?

那么，电通量与同心球半径无关吗？

And then you have another spherical wave coming from the short bank.

然后会看到另一个来自短波岸球波。

Spherical reflectors don't perfectly focus all the incoming rays.

球反射器不能完美地聚焦所有入射光线。

The integral of dA is A; the area of the concentric spherical surface.

dA积分是A;同心球积。

As an example, Borsuk-Ulam also applies to mapping hyperspheres in 4d space into 3d space.

例如，Borsuk-Ulam 还适用于将 4d 空间中超球映射到 3d 空间。

And you can see this when the ball back by the spread-out lines of oil on the ball surface.

球从球上油线中滚回时， 可以看到这一点。

Say we have a lens that has a spherical face on both sides, known as a convex lens.

假设我们有一个具有球头 两侧，称为凸透。

Initially the telescope used line feeds, elongated receivers that could gather signals within the focal line of the spherical dish.

最初， 望远使用线馈送，细长接收器可以收集球盘焦线内信号。

There actually is something called the Riemann sphere that involves dividing by zero by a different method, but that's a story for another day.

事实上，有个叫黎曼球东西，它涉及到通过不同方法来除以 0，但今天我们且不谈这个。

Rather than using a parabolic shape for the dish that would focus everything to a single point, they chose a spherical curve.

他们没有使用将所有东西都集中到一个点抛物线形状，而是选择了球曲线。

So, as a spherical wave moves farther from its source, its intensity will decrease by the square of the distance from it.

因此，随着球波远离其源，其强度将按距其距离平方而减小。

So you can start seeing the waves are coming from the long bank here, and you can see they're making a spherical wave.

所以可以开始看到波浪从这里长河岸传来，可以看到它们正在形成球波。

China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST), the world's largest single-dish radio telescope, opened to global scientists and began accepting observation applications from astronomers starting from March 31.

世界上最大单盘射电望远中国五百米口径球射电望远（FAST）向全球科学家开放，并从 3 31 日开始接受天文学家观测申请。

So what we see as a unit sphere in our 3d space represents the only unaltered part of the hypersphere of quaternions getting projected down on to us.

因此，我们在 3d 空间中看到单位球体代表了投射到我们身上四元数超球中唯一未改变部分。

Actually, the electric field has the  same magnitude as it passes through every infinitesimally small area, dA, on the  concentric, spherical surface through which we are finding the flux.

实际上，电场穿过我们正在寻找通量同心球上每个无穷小区域 dA 时，它具有相同幅度。

Engraved upon the smooth golden surface, where seconds before there had been nothing, were five words written in the thin, slanted handwriting that Harry recognized as Dumbledore's: I open at the close.

刚才还什么都没有平滑金色球上，出现了五个瘦瘦凸起斜体字，哈利一眼就认出来那是邓不利多笔迹：我打开了最后。