You are an electron. Therefore at death you survive, and explore the universe.
All experience is a mixture of yes and no. Should I do "a" or "b"? Yes or no? Do I feel love? Yes or no? What is this feeling of love: relaxed? Yes or no? hjappy? yes or no? Wanting the loved one to be happy? Yes or no?
This might seem reductive, but look at the alternative.
"Darling, I love you, but I do not need to say yes or no."
"Do you really love me?"
"I cannot say."
"Will you help me with this shopping?"
"I cannot say."
"How do I know that you love me?"
"You feel it!"
"How can I feel it if you don't say it and don't help me?"
So we can explain everything through yes or no. And we cannot explain anything without yes or no. This is true of all reality, from the simplest mathematical statement (does 1 equal 1? Yes or no?) to the most complex global ecosystem (is the planet healthy? Yes or no?). So all reality, including the mind, is made of nothing but yes and no.
Since the mind is made of "yes" and "no", how do we know which yes is which? What if we think of one "yes" and accidentally mix it up with another that should have been "no"? We all have experience of being distracted like this. And we all know the solution: deal with one question at a time. That is, work in serial, not parallel.
We think we are seeing many ideas at once, but in reality we are switching between them so quickly that we are not even aware that we are switching. For example, when I look out of the window and think I see everything at once, really my eyes are darting from point to point. It is the same when I imagine the scene in my mind: I have a vague belief that I see it all, but as soon as I think about it I am focusing on some detail or other. The brain delivers the goods faster than it takes for me to change focus, so it feels like everything is there at the same time. For experimental examples of this, see Nick Chater's book "The Mind Is Flat"
This logic applies at every scale: the mind is serial at every scale. So it follows that the mind is simply a single "yes/no" that changes very rapidly.
Any particle could do the job of switching yes/no in response to input. Evolution happened by accident, so nobody was deciding "let's create some exotic new particle for the human mind." All chemistry is based on electrons, so the "mind particle" is probably an electron as well.
Brain structures began to evolve when the very first living molecule resisted change (bad!) and made even more of itself (good!). As the brain grew more complex he message was always the same: maintain yourself: good. Change yourself: bad. So eating, being healthy, having shelter, reproducing, are all good. Bodily damage, growing old and dying alone, bad.
So the ideas of "bad" and "good" evolve from "change" (bad) and "no change" (good). We already know that decisions evolve from simple "yes/no" states. So the basic unit of the mind is change (bad) versus no change (good). of course, if the mind is controlling a complex body then change is inevitable, so at that stage doing nothing means decay, but if we know that all problems of decay are solved, then doing nothing is the best thing ever! Think of an old couple in their rocking chairs surrounded by a loving family. Or a young couple lying on the beach sunbathing. If all your needs are take care of, then doing nothing is the happiest thing ever!
We might object and say "change can be fun - I hate boredom!" But this ignores the change we don't see. In a complex body, cells are always dying, energy is always being used, and threats are always nearby. So doing nothing means change increases to fatal levels. So when we stimulate the senses we feel better able to face challenges, and that feels good. Ironically, a roller coaster ride feels exciting precisely because it wakes us up in order to prevent change!
The mind is part of a subatomic particle, so if the brain dies and decomposes that particle will simply change at a slower rate. Since change "bad", this lower rate of change will feel great. We get glimpse of this in near death experiences. As the brain begins to shut down, people generally report feeling euphorically happy.
Thanks to gravity, particles tend to be attracted into stars, then might be recycled into new planets. That is, you will be surrounded by billions and trillions of minds just like yourself, all doing the same thing. You will all be sharing your experiences: the more of you there are, the greater the gravitational and electromagnetic waves you create, so the more you affect everyone else. It is one great big excited conversation (Literally excited: electrons exist in a state of excitation!)
Most particles will end up as black holes, which then evaporate. Since time is no concern, the future could be very interesting. Each stage might take vastly long periods of time, but the mind (without the brain) does not mind time passing: lack of change just feels really, really good.
Some people say that humans are self aware. This is hard to take seriously, as possibly nothing in the universe is less self aware than humans. Most of us have no idea what we are (electrons), and are terrified of the best thing that will ever happen to us (freedom at death). Even the simplest amoeba is more self aware than us: its body is more directly in touch with its reality: the need to eat and to avoid damage. It does not create a fake, illusory model of reality in its head (because it has no complex brain) and therefore cannot be confused into crazy actions like destroying its own environment or changing technology faster than it can react.
All our claimed understanding and depth is an illusion: we are aware of vanishingly little - just a series of happy/sad feelings, just like every other electron. We think we connect to the universe, but in fact our brains and technology add insulating barriers between us and the outside world. We think we understand reality, but instead we fight against it, creating more and more change, therefore becoming more and more unhappy. Humans are idiots. But like all idiots we will destroy ourselves, and so happiness is restored again.