To my knowledge, there is no scientific evidence of life after death. Why do so many people believe in the afterlife without scientific proof?

Warning, we are going to touch the Void. The vacuum is holding the key to solve the greatest mysteries of modern physics and other scientific fields. We know from experiments that even though the absolute zero pressure is reached the vacuum hold still a huge amount of remaining energy called zero-point energy.

The size of this energy is monstrously big, it is ten times larger than nuclear energy. Physicists John Wheeler and Richard Feynman calculated that there is enough such energy in the vacuum inside a single light bulb to boil all the world's oceans.[1]

We are pretty sure that there is a lot of things happening down there at the Nothingness. We are unable to see there anything, yet we are sure according to our observations and computations that there is a lot.

People who are going through near-death or after-death experiences are describing the world which they entered and as the world of light and sound, all is made from fields that are resonating and creating beautiful fractal & Tibetan mandala-like structures. Those fields are perceived as more fundamental than our material world.

Let us turn our attention back to quantum chromodynamics that describes the universe as ever moving quantum fields from which arises all particles and mater as we observe it. It is known a long time ago. The problem is that we are unable to compute those fields as they are extremely computationally expensive and their computations lead to the most intractable computational models known to humanity.

So observation of quite of few people who went far beyond the point of the clinical death is consistent with observations of quantum chromodynamics.

So the conclusion is that our soul/consciousness are possibly existing in the area of zero-point fields and energies, where we do not have measurement tools capable to detect them directly. We are pretty sure that there is going on something strange but we still do not put our hand on it.

Quantum fields can exist independently of all particles that create our material world. Hence, there is a great chance that our bodies are created from both: particles & quantum fields.

Personally, I would be very cautious with any strict statements of the type that soul/consciousness is not existing. That all especially in the light of already achieved knowledge in the fields of quantum thermodynamics and exploration of near-death experiences.

Footnotes

[1] Zero point energy | Education | The Guardian