Читать книгу String Theory For Dummies - Andrew Zimmerman Jones - Страница 44

Because matter causes a bending of space-time, cramming a lot of matter into a very small space causes a lot of bending of space-time. In fact, some solutions to Einstein’s general relativity equations show situations where space-time bends an infinite amount — called a singularity. Specifically, a space-time singularity shows up in the mathematical equations of general relativity in the following two situations:

 During the early big bang period of the universe’s history

 Inside black holes

These subjects are covered in more detail in Chapter 9, but both situations involve a density of matter (a lot of matter in a small space) that’s enough to cause problems with the smooth space-time geometry that relativity depends on.

These singularities represent points where the theory of general relativity breaks down completely. Even talking about what goes on at this point becomes meaningless, so physicists need to refine the theory of gravity to include rules for how to talk about these situations in a meaningful way.

Some believe that this problem can be solved by altering Einstein’s theory of gravity (as you see in Chapter 20). String theorists don’t usually want to modify gravity (at least at the energy levels scientists normally look at); they just want to create a framework that allows gravity to work without running into these mathematical (and physical) infinities.