allocated object address as high as 46th bit (i.e in the 131072 GB range)

[Richard (Rikki) Andrew Cattermole]

As far as I'm aware, no cpu that you can get ahold of support more than 
48bit of address space at the hardware level.

There is simply no reason at this time to support more, due to the fact 
that nobody has implemented anywhere near that maximum.

Also worth noting, the address a block of memory is, has no relation to 
the hardware. A kernel will instruct the cpu to map it wherever it 
pleases per process.