Gravity Curves Space-time. That’s It: "On Gravity: A Brief Tour of a Weighty Subject" by Anthony Zee

On Gravity: A Brief Tour of a Weighty Subject - A. Zee


“That space and time are replaced by spacetime immediately tells us how a field, be it electromagnetic or gravitational, varies in time once we know how it varies in space.”

In “On Gravity: A Brief Tour of a Weighty Subject” by Anthony Zee


“Einstein says the space-time is curved and that objects take the path of least distance in getting from one point in to another in space-time. The curvature of space-time tells the apple, the stone, and the cannonball to follow the same path from the top of the tower to the ground.”

In “On Gravity: A Brief Tour of a Weighty Subject” by Anthony Zee


“Gravity curves space-time. That’s it.”

In “On Gravity: A Brief Tour of a Weighty Subject” by Anthony Zee



On August 17, 2017 two neutron stars collide (Zee references this in his book). 

Let me hypothesize: consider a particle on the surface of one of the neutron stars belonging to a pair, about 10 km from the centre. It's being pulled downwards by an enormous gravitational force - about a hundred billion times stronger than gravity on the Earth's surface (if I calculated it right). But if the particle is going really, really fast (for example, close to the speed of light) it's still able to escape the star and not get pulled back in.

There's more stuff on the other side of the rainbow: you can read the full review.