Throughout the ages, humanity has wondered about the nature of the phenomenon commonly known as "death" and the possibility of existence beyond earthly life. This book invites us to explore the depths of these ancient questions through the lens of metaphysics as applied to modern science for an understanding of the essence and nature of the human spirit.

Before the advent of quantum physics, the world of invisible phenomena, located beyond human comprehension, was traditionally reserved for metaphysics, a philosophical discipline that deals with ontological and transcendental issues. The old distinction between what is material and what is spiritual was sharp. Physics was focused on the study of physical and measurable phenomena, while metaphysics dealt with metaphysical questions, such as the essence of the soul, the nature of consciousness and life after the passage.

However, with the quantum physics revolution in the early twentieth century, the very foundations of reality were shaken. Experiments at the subatomic level revealed behaviors of matter that were completely different from what was predicted by the laws of classical physics. Concepts such as quantum superposition, entanglement and wave-particle duality were introduced. These phenomena are elusive, cannot be directly observed and challenge our traditional conception of objective, deterministic reality.

In this context, what once belonged to the domain of metaphysics, such as the nature of human consciousness or the immortality of the soul, is gradually becoming an object of study for theoretical physics.

A number of pioneering scholars are trying to develop physical models that can explain seemingly nonphysical phenomena that are closely related to our human experience.

For example, consciousness is increasingly seen as an emergent phenomenon related to the complexity of the brain and its interactions at the quantum level. Similarly, some theories postulate the existence of dimensions in space-time that could allow the existence of nonmaterial realities, opening the door to hypotheses about the immortality of the soul or the possibility of existences beyond the physical passage.