Part one: Will copies of human beings one day end up in the
metaverse?
In my upcoming novel, Beside
an Open Window, human beings make regular digital scans of their brains
while alive so that these can be activated in a vast online world once they die.
The book is set sixty years into the future and ‘dead residents’ interact in
this world with living residents who access it in much the same way as we do
Second Life® today.
Glass brain, the latest output from Philip Rosedale
The idea of creating brain scans is one I’ve been thinking
about for several years. Some time before SL existed, I remember wondering if
it might one day be possible to create ‘archived’ copies of brains on
computers. It was less an issue to me at the time that we might do so in order
to extend in some way human existence and much more that we might do this to prevent
the loss of people’s thoughts and memories. I think this had a lot to do with
the death of my father, who I missed profoundly and whose thinking and
experiences I considered a genuine loss to his fields of interest.
When I got into SL, the idea that such archives might connect
to the metaverse – and thereby have natural movement in a virtual world – was very
compelling to me. I hadn’t put a great deal of thought previously into how
digital brains might interact with the world, oscillating broadly between a
very basic ‘brain-in-a-jar’ scenario where an archive was switched on
periodically for electronic consultation and the full-blown (and, frankly,
unlikely) ‘holodeck’ notion promoted in Star Trek. Somewhere in the middle of
all that I’d also thought fleetingly about uploading brain scans to robots – an
idea I later discovered was explored by Janet Asimov in her novel, ‘Mind
Transfer’.
In a virtual world, however, a brain could roam about with
freedom in a virtual body and consume only a fraction of the energy and costs
of any robot or far-fetched holodeck idea.
Could such a thing, then, actually be possible? There are a
few conditions which would have to be met. Firstly, it would have to be
possible to scan a brain at a resolution able to identify individual molecules.
Memory is stored via pathways through different neurons, the route that an
individual signal takes through them being determined by the quantities of
neurotransmitter chemicals passing across the tiny gap between one neuron and the
next – the synapse – and the receptiveness of the receiving neurons to these
chemicals. Only by knowing the exact state of all of this could we create a
scan that was in any way functional. No such technology exists today, although
the resolution of brain scanning is continually improving. By interesting
coincidence, one recent innovation allowing users to scan and view their brain
activity in real-time – ‘Glass Brain’ – has been co-developed by none other
than SL’s own Philip Rosedale.
Secondly, we would need gigantic computer memory capacity
for storing brain scans. One estimate I read recently was that there are
something approaching 500 trillion trillion atoms in a human brain. Assuming
this is true and assuming we assigned one byte of computer memory to the
description of each atom, my back-of-an-envelope calculations indicate we would
need something in the region of 50 trillion terabytes to store all this. Applying
Moore’s Law to computer memory growth – starting at 8 gigabytes for a mid-price
desktop system today – we might predict that the computers of 2064 will have
memories in the region of 250,000 terabytes, which is rather a long way short
of what we’d need. Add another sixty years of Moore’s Law progression, however,
and you’re pretty much there.
Thirdly, we’d need to be able to bring these scans to life:
their data would have to mean something to the computers they’re loaded into,
just like a jpeg means something and an MP3 means something else. We’d need to
understand the precise function of neurons and brain chemistry in order for
this to happen, such that each neuron’s data description can be turned into a
fully emulated brain cell once the model’s switched on and digital blood
applied. We’d need to know how visual input is encoded in the eye and sent down
the optic nerve if we want our dead people to see in the metaverse and how
auditory input is encoded in the cochlea if we want them to hear. Sensory
input, in fact, would be a huge area for further research: contrary to popular
belief, the brain receives input far more complex than just ‘the five senses’. For
example, shut your eyes and hold your hand at arm’s length, then move it
towards your nose but stop just short of touching it: how did you know where your
hand was in terms of what sight, sound, smell, taste or touch were telling you?
Even supposing we work out how to do all these things,
however, there could still be another enormous barrier to emulating the mind:
consciousness, without which a human brain is nothing. In Beside an Open Window the theory of consciousness as emergent
behaviour is assumed. Emergent behaviours are apparently organised behaviours
that emerge from the more simple behaviours of large collections of smaller organisms.
The seemingly simultaneous movements of flocks of birds or shoals of fish –
movements which give the impression of an organised whole rather than lots of
disorganised individual components – are examples of this. In science fiction,
the idea of higher order behaviours arising out of the more mundane work of
component individuals is something that’s most famously been explored in Star
Trek through the notion of the ‘hive mind’ of The Borg. Human consciousness as
an emergent behaviour of neurons – ultimately, then, an illusion of sorts – is something
that ‘just happens’… but would it happen also in a digitally modelled brain?
That’s the sort of thing we can’t possible know until we actually try it out.
Supposing, then, that consciousness does happen, what would
existence be like for these resurrected brains? What would they do? What would
it be like to live in a digital world and only be able to look back into the
real one, as though through a window? I’ll examine some of these issues in part
two of this article next weekend.
No comments:
Post a Comment