Two questions:

1. What does **it** and **one** refer to in the following sentences?
I myself think that it refers to the **very fabric of spacetime**. Am I correct?
2. What is the meaning of the verb ***blows up*** in this context?

> 
> According to quantum
>  theory, the very fabric of spacetime is subject to the
>  violent fluctuations caused by the formation of virtual particles
>  on the small scale—fluctuations that become ever
>  more extreme the smaller the scale until eventually **it** all
>  blows up when **one** theoretically gets down to a point
> 
> 
>