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A game you're almost certain to lose...

What are the challenges of communicating from the frontiers of mathematical research, and why should we be doing it?

Celebrate Pi Day with the stars of our podcast,

*Maths on the move*!Maths meets politics as early career mathematicians present their work at the Houses of Parliament.

Celebrate this year's International Women's Day with some of the articles and podcasts we have produced with women mathematicians over the last year!

To escape an object's gravitational pull you just need to have enough kinetic energy to balance the gravitational potential energy — that is you have to be able to achieve the

escape velocity. The acceleration in the article refers to something stationary on the surface of the object accelerating to this escape velocity. As you say the speed of light is constant, it does not accelerate. Therefore if the escape velocity at the surface of a body is greater than the speed of light (so the radius of the body is smaller than the Schwarzschild radius), then nothing, not even light will be able to escape from the gravitational field.