why did chris change his name to alex? what was he hoping with his new identity?

Chris was a free spirit. He was a counterculture adventurer who escaped the shackles of prescribed society and lived for the moment. Chris ended his relationship with endless consumption and simply went out and experienced people and places for what they really were. That is how Chris was a romantic. He was also very personable. He really became this alter ego "Alexander Super tramp". Alexander Supertramp personifies Chris's sense of adventure and counter-culture. The new identity helps sever Chris from his old identity and his old world.