That work became an important piece of evidence that dark energy — the mysterious force propelling the acceleration of the universe outward — actually exists.
这项工作成了暗能量（这是推动宇宙向外加速的神秘力量）确实存在的一个重要证据。
2
Attach a sharp stone to the end of astout piece of wood, and with this lever you can hugely increase thespeed, force, effectiveness and safety with which the axe can bewielded.
In March of that year James Clerk Maxwell, a Scottish physicist (pictured above), published the first piece of a four-part paper entitled "On physical lines of force".