I will have to check out that book.
I think it's clear there are energies and dimensions that we as humans, in our natural state, are incapable of sensing except maybe during the afterlife.
I'm copying Joe Rogan's analogy but he made a good point. Imagine if all humans and animals were not equipped with a sense of smell. The scents would always be there, but we would not even know what a scent is. If one person was able to smell, he/she would not be able to describe it to anyone else, and would probably be thrown into a mental ward.
Scientists are hypthesizing about the likelihood of an infinite universe with numerous dimensions. One dimension would be an exact copy of our world/solar system/galaxy with another you doing the same exact thing somewhere else. Other dimensions would be similar, but with slight differences. Maybe Elvis was alive and Adolf Hitler, not a dictator was at the front row of his performances.
Other dimensions would not follow the same physics of the world we know today at all.
How do you explain emotional connections between identical twins who are thousands of miles apart? After a power outage, how do dogs and cats seemingly know when it's about to come back on. (I've witnessed this with scary consistency, they will wake from a dead sleep and bark/meow at nothing, and boom the power comes back on). People born blind and have no concept of what sight is, sometimes see for the first time during a near death experience.
I wish we could grab a couple hundred deep forest south american tribesman and get them on strong DMT breakthroughs. Would any of them see the grey aliens that a percentage of us see on DMT trips? Or are they created from our exposure to alien folklore? The tribesman have no exposure to our pre-concieved "aliens", and even a few of them describing (or not) describing the "greys" will tell us a lot about what to percieve these entities as.