Can you create two different DNS records that resolve to same IP?
Yes, use cnames. Done all the time especially with web servers.
No, do not use multiple PTR's.
"War is an ugly thing, but not the ugliest of things. The ugliest is the man who thinks nothing is worth fighting and dying for and lets men better and braver than himself protect him." - John Stuart Mill, 1859
"To lodge all power in one party and keep it there is to insure bad government." - Mark Twain