I thought of a concept and I wanted to know if it is possible or according to the Torah it is an impossobility. the concept is that Tchiyat Hamatim is the actual dying of the person and in essence we are dead in this world and come to life after death?

Although there are references in rabbinic literature to life in the world- to- come as being "more alive"- eternal, constantly active without the inertia of matter- than life in the physical world, belief in Tchiyat Hameitim is belief in a reuniting of the soul and body. Rambam explains that the body in T'chiyat Ha meitim is unchanged from the physical body as we know it today. Ramban disagrees and sees the body at that period as becoming less material. Belief in T'chiyat Hameitim is one of the thirteen principles of faith. Therefore while it is legitimate to explore and investigate its meaning based on comparing Jewish sources and evaluating their meaning for you, it is important not to adopt an explanation that negates its essence. That essence is the perfection, not only of the spiritual world, but also of the physical world as well.