From a religious point of view, not only are we human beings spiritual, but actually everything is spiritual. After death, the soul does not die, circulating in the six paths. According to what you have done in this life, the soul is taken to different places; It is difficult to define what kind of form and material state the soul is. Now more practitioners call it "spiritual body". It is not so much a special electromagnetic wave as a combination of spirit and energy field. A person's past life is the reincarnation of a spiritual body.
If you want to know something about past lives, you can find a video like this/u97//u97 /u97/v_MjY3ODQ5MTA.html
By the way, religion is by no means a so-called "superstition", it comes from a higher civilization system. And this civilization did not come from the earth. It may be difficult for you to understand what I said, but it's true. Its development is at least tens of millions of years ahead of the current human civilization.