In This Topic
M-theory re-energizes the movement Thinking about branes Overcoming the conundrum of dark energy So many string theories, why pick just one?
The last topic ended with five versions of string theories. Theorists continued their work, but were uncertain how to take these findings. A new insight was needed to generate further progress in the field.
In this topic, I explain how that insight came about in the form of M-theory, which unified these string theories into one theory. I discuss how string theory was expanded to include objects with more than one dimension, called branes. I introduce some possible insights that may help explain what M-theory is trying to describe. I show how the discovery of dark energy, unpredicted by string theory, has complicated string theory, as well as introduced a large number of possible correct solutions to the theories. Finally, I examine how some physicists have used the anthropic principle to try to give meaning to this landscape of string theories.
