His thesis is that the EU is best understood as three concentric spheres.

在他的理论下，欧盟可被视为三个同心球体。

Portrayed as a powerful, heavenly figure, she leads Dante through " Paradiso's" concentric spheres of Heaven until he is finally face-to-face with God.

她被描绘为一位强大且神圣的人物，引领但丁游历《天堂》的九重天，一直到和上帝面对面。

The concentric sphere has a constant radius, so the  electric field there is constant.

同心球的半径恒定，因此那里的电场也恒定。