Hello blog readers. So I was thinking, "how can I seriously depress the lovely Daniweb visitors today?". Then it hit me: The End of All Life (EAL). I was reading an article in Physics World a few years ago about some predictions on the long term survival prospects of life, based on known physics. The most important point made regarded the expansion of the universe. A major survey of supernova explosions over the visible history of the universe (surprisingly) seemed to show that this expansion has been accelerating for a long time.
The suggested reasons for this are another story in themself. Now, consider an advanced civilisation. Their home star has run out of fuel and died and to avoid the same fate they must travel the universe in search of more energy (or they will freeze, or starve, or both). To cut off the hopeful sounding "but an advanced species would have bases near many stars", let me say this: all stars will eventually come to a cold, tragic end. GAME OVER already then? Perhaps not.
It is believed that as many as half of all stars may end up as black holes. Current physics suggests that the matter (and hence energy) of the dead star inside a black hole may escape to the surrounding space, albeit at a very slow rate inversely proportional to the star's mass. The energy actually comes from the vacuum just outside the event horizon and it's release causes an equivalent reduction in the black hole mass. This is a sneaky was to bypass the whole "nothing can escape from a black hole thing".
So our advanced species could travel vast distances and collect infinite energy from the infinite [1] number of black holes right? Wrong. The accelerating universal expansion would mean that each time they wanted to travel to another galaxy it would be further away (on average) than the last one was. A point would be reached when they would always expend more energy on the journey than they could collect from distant black holes. Now it's surely GAME OVER?
This is where the computer science comes in. The species's last chance might be to evolve into somthing that can use energy at a continually decreasing rate, while still remaining sentient. However, in 1961 Rolf Landauer of IBM argued that "any logically irreversible manipulation of information,......must be accompanied by a corresponding entropy increase in non - information bearing degrees of freedom of the information processing apparatus or it's environment". Which means, when you consider that energy is quantised, that the rate of energy usage by a computer cannot be reduced arbitrarily close to zero.
Now I'm not saying that a sentient being is just a computer with feelings. But that intelligent life must involve the processing of information, I would like to see argued away. So, looks like it's curtains then. Thanks for reading.
Steven.
[1] That the number of black holes in the universe is infinite could only be true if the universe were spacially infinite. This is not proven and is still debated.
