One of the most counter-intuitive notions in physics is that all objects fall at the same rate, regardless of mass, aka the equivalence principle. This was memorably illustrated in 1971 by NASA Apollo ...

One of the most basic assumptions of fundamental physics is that the different properties of mass -- weight, inertia and gravitation -- always remain the same in relation to each other. Although all ...

If you simultaneously drop a feather and a bowling ball in a vacuum, they’ll hit the ground at the same time. In other words, despite their mass, they’re affected by a gravitational field in exactly ...

Researchers present the most precise test yet of the weak equivalence principle, a key component of the theory of general relativity. The report describes the final results from the MICROSCOPE mission ...

A clear explanation of the equivalence principle, the idea that gravity and acceleration can be indistinguishable, and why it is central to modern physics. John Ivison: Trump’s tariffs on Canada are ...