Reincarnation as a religious concept states that human beings upon our Earthly demise are reborn into a new state of existence. In judeo Christian religion it is either Heaven, purgatory or Hell. Some Eastern Religions preach an eternal cycle of Death and rebirth aka reincarnation.
Hindus refer to this concept as Saṃsāra which has no equivalent English word, but has been translated to mean a form of 'wandering' or transmigration with connotations of a cyclical nature. It is an integral part of the 'karma' theory which most are somewhat familiar with.
A fairly new theory from Dr. Robert Lanza states that death as we presently define it is an illusion that in reality does not exist. The body itself does not generate consciousness, it lives on after the body dies. The body as per Lanza receives consciousness in much the same way a radio receives a signal. Lanza states that space and time are luggage we tote around with us "like turtles with shells " when the shell comes off (space and time), we still exist.
"A human being is part of the whole called by us universe , a part limited in time and space. We experience ourselves, our thoughts and feelings as something separate from the rest. A kind of optical delusion of consciousness. This delusion is a kind of prison for us, restricting us to our personal desires and to affection for a few persons nearest to us. Our task must be to free ourselves from the prison by widening our circle of compassion to embrace all living creatures and the whole of nature in its beauty...We shall require a substantially new manner of thinking if mankind is to survive." - Albert Einstein
Dr. Lanza is not another quack with a mail order degree, he is a respected specialist in regenerative medicine, Head of Astellas Global Regenerative Medicine, Chief Scientific Officer of the Astellas Institute for Regenerative Medicine and Adjunct Professor at Wake Forest University School of Medicine. He is also familiar with and has done work in the fields of physics, quantum mechanics and astrophysics. He was voted the 3rd most important living scientist by the NY Times, that of course is based on our conventional definition of 'living'.
His theory is outlined in his book Biocentrism: How Life and Consciousness Are the Keys to Understanding the Nature of the Universe
Lanza is also a proponent of the 'multiverse' theory and believes that multiple universes can and probably exist side by side and simultaneously. In one universe, the body may be dead yet continue to exist in another.