Why does lvm physical volume have significantly less space than the actual underlying device it contains?

Issue

• pvcreate command use a lot of space
• 3 disk presented to linux server 1) 6.3TB & 2) 5.4TB disk. After pvcreate created on the disk the sizes are now 1) 5.73TB & 2) 4.9TB devices. That is a lot of overhead. Is there a way or an option to pass that reduce the overhead on pvcreate?

fdisk :
Disk /dev/sdb: 5400.9 GB, 5400911437824 bytes
Disk /dev/sdc: 6301.1 GB, 6301063340032 bytes
Disk /dev/sdd: 5400.9 GB, 5400911437824 bytes

pvs:
/dev/sdb   volgrp02 lvm2 a--    4.91t   4.91t
/dev/sdc   volgrp02 lvm2 a--    5.73t   5.73t
/dev/sdd   volgrp02 lvm2 a--    4.91t   4.91t