Would it likely be possible, if eventually as technology has advanced enough, that a human could turn his/herself into pure energy, and maintain consciousness and sentience, so as to be invulnerable to all or most of the dangers in the universe.

 

As we understand it, our consciousness is a product of the electrochemical signaling between neurons.

 

Now if we replaced each neuron, one at a time, with a non-organic human-made neuron that performs the same action, the data from the old neuron is always stored in multiple places in the brain, correct?

 

So as we take one out at a time, replacing it with a man-made neuron, would our consciousness (who we are) remain the same? Because the information that would be stored in one neuron was stored in multiple places, so that as each neuron is replaced, information would flow back into the artificial neuron, keeping us sentient and conscious?

 

Couldnt a humans consciousness, evolve from cyborg -> android -> pure electrical signals -> to pure energy? Or is there nothing to define one electrical signal to another when we take that next step? Are humans doomed to mortality?

"Turning into pure energy" doesn't mean anything. Energy is a property, not a substance. You can't be a "being of pure height" either. This is a common and annoying trope in soft sci fi, where "energy" usually means "glowy, wispy stuff."

 

"Evolution" also has a specific definition in science which does not correspond to what you're talking about.

 

Aside from that, what you're basically talking about is transhumanism, which a lot of people (including myself) believe is quite possible, though not yet to the degree you're asking about.

 

http://en.wikipedia.org/wiki/Transhumanism