In French mechanical treatises of the nineteenth century, Newton's second law of motion was frequently derived from a relativity principle. The origin of this trend is found in ingenious arguments by ...

Einstein’s theory of general relativity suggests that our universe originated in a Big Bang. But black holes, and their gravitational forces, challenge the limits of Einstein’s work.

But, in the spirit of relativity – that space and time only have meaning when they are relational – we may need to rethink basic ideas.

If gravity arises from entropy, scientists could unite Einstein's general relativity with the quantum realm while shedding light on dark matter and dark energy.