The VM has a set of threads called schedulers, all running in parallel. Each scheduler has in turn a set of Erlang processes (possibly thousands) to run. Every process has a pointer to its own separate chunk of heap where it allocates its stuff.

The language has no concept of pointer, so there is no way to create a reference to memory owned by another process. You can send a message to another process, but internally the VM will copy the message to that process’ heap.