Births and deaths are the most important events that happen in the survival path of species. While birth is not considered as mystery, almost every one everywhere, prefers to believe that death is mystery. For the believers, death is something that is secret; something that is impossible to understand. Even for the enlightened ones death is something that arouses curiosity through its obscure nature.
Science has disproved the concept that death is a mysterious event: According to science, births and deaths are inevitable events and are inter-connected. In a broader sense, death has got to be considered as part of continuation of life itself. The continuation prescribes no escape for life from the clutches of death.
Life is cell-to-cell communication and therefore, death is stoppage of the communication due to non-functioning of the signalling system. Loss of the signalling process is the result of depletion in cell growth and abnormal loss of nerve energy. In the case of living organisms, promotion of reproduction seems to be the emphasis of Evolution. The course of existence necessitates higher degree of cell-to-cell communication which in due course of time deprives the cells of its much needed energy for sustenance. Thus death becomes the ultimate remedy to resolve the decree of evolution whenever and wherever stoppage of cell-to-cell communication takes place.
It is clearly written down in the dictionary that the word mystery refers to something that is secret or something that is impossible to understand. Death and birth are not things that are secrets to understand, things that are impossible to understand. Sustenance of life depends upon the healthy existence and normal functioning of both the body cells and the nerve cells in the organism. Anything that hampers this function damages the light of life. Anything that stops this function stops the light of life to exist. Extinguishing the light of life may happen suddenly or slowly over a period of time depending upon the way in which the cells, both the body cells and the nerve cells in the organism, get affected. A gun shot or a sudden cardiac arrest extinguishes light of life suddenly; an attack from bacteria or viruses may lead the light of life getting extinguished slowly over a period of time.
Whatever way the light goes out, death is not a mystery: Death is quite a natural, physiological process aimed towards the end. A person may die either in the natural way or by suicide or by and through an assassin: Whatever way it happens, the inherent process is malfunctioning or non-functioning of the cells caused or followed by bronchial-cardiac arrest.
What happens after death? Answer to the question is simple: Nothing happens after death as far as the one who died, is concerned. The lifeless body of the one who died has got to be buried or burnt. Burial or burning of the dead body would have to be done by others who are alive and available around for the task. If not buried or burnt, the body will naturally find its removal by decay and through consumption by worms and insects.
That is all there is to it: Nothing more and nothing less. Death is not a mystery; there is nothing mysterious about death.
There is no such thing called soul in the universe: Soul does not exist anywhere in the world or outside the world. Therefore soul does not play any role to sustain life. Non-existent soul cannot interfere in matters of births and deaths. Since no soul or spirit exists for its escape at the time of death, there is no question of rehabilitating the soul or allowing the soul to wander around haunting living entities in the guise of ghosts.