Yes .. it is proven .. scientifically and all the religions accept some forms of re-birth. Hinduism and Buddhism has much more better religious explanation because of the nature of the religions. Remember, historically they agree that Indian region had the first religions. So logically they had time and capacity to think and explore these religious matters ..
Once scientist in USA ( who didnt have any Buddhist background ) did a series of experiments for this matter.. and found very convincing evidence for that. But because he was not a religious person he concluded of a phenomenon which is new to science.
you can read about Dr. Ian Stevensons studies about reincarnation here
http://en.wikipedia.org/wiki/Ian_Stevenson .. Any more questions please don not hesitate to ask
This is the nature of Buddhism . any person can question .. and if any person explore with a fair mind they will see the truth in Buddhism..