Matrix-style virtual worlds

I put this article in, in it's entirety even though the technical parts are somewhat beyond me. The picture it paints is a mind blowing reality. So, are we just holograms ourselves as some scientists are starting to think? What is our reality? What is general reality? Questions, questions....
Matrix-style virtual worlds 'a few years away'
* NewScientist. com news service
Are supercomputers on the verge of creating /Matrix/-style simulated
realities? Michael McGuigan at Brookhaven National Laboratory
in Upton, New York, thinks so. He says that
virtual worlds realistic enough to be mistaken for the real thing are
just a few years away.
In 1950, Alan Turing, the father of modern computer science, proposed
the ultimate test of artificial intelligence – a human judge engaging in
a three-way conversation with a machine and another human should be
unable to reliably distinguish man from machine.
A variant on this "Turing Test
" is the "Graphics Turing
Test", the twist being that a human judge viewing and interacting with
an artificially generated world should be unable to reliably distinguish
it from reality.
"By interaction we mean you could control an object – rotate it, for
example – and it would render in real-time," McGuigan says.
Photoreal animation
Although existing computers can produce artificial scenes and textures
detailed enough to fool the human eye, such scenes typically take
several hours to render. The key to passing the Graphics Turing Test,
says McGuigan, is to marry that photorealism with software that can
render images in real-time – defined as a refresh rate of 30 frames per
second.McGuigan decided to test the ability of one of the world's most powerful
supercomputers – Blue Gene/L
at Brookhaven National Laboratory in New York – to generate such an
artificial world.Blue Gene/L possesses 18 racks, each with 2000 standard PC processors that work in parallel to provide a huge amount of processing power – it
has a speed of 103 teraflops, or 103 trillion "floating point
operations" per second. By way of comparison, a calculator uses about 10
floating operations per second.In particular, McGuigan studied the supercomputer' s ability to mimic the interplay of light with objects – an important component of any virtual world with ambitions to mimic reality.He found that conventional ray-tracing software could run 822 times faster on the Blue Gene/L than on a standard computer, even though the software was not optimised for the parallel processors of a
supercomputer. This allowed it to convincingly mimic natural lighting in real time.
Not there yet "The nice thing about this ray tracing is that the human eye can see it
as natural," McGuigan says. "There are actually several types of ray-tracing software out there – I chose one that was relatively easy to port to a large number of processors. But others might be faster and even more realistic if they are used in parallel computing."Although Blue Gene/L can model the path of light in a virtual world both rapidly and realistically, the speed with which it renders
high-resolution images still falls short of that required to pass the
Graphics Turing Test.But supercomputers capable of passing the test may be just years away, thinks McGuigan. "You never know for sure until you can actually do it,"
he says. "But a back-of-the- envelope calculation would suggest it should
be possible in the next few years, once supercomputers enter the
petaflop range – that's 1000 teraflops."But others think that passing the Graphics Turing Test requires more than photorealistic graphics moving in real-time. Reality is not 'skin deep' says Paul Richmond at the University of Sheffield, UK. An
artificial object can appear real, but unless it moves in a realistic
way the eye won't be fooled. "The real challenge is providing a
real-time simulation that includes realistic simulated behaviour," he says.
Fluid challenge
"I'd like to see a realistic model of the Russian ballet," says Mark
Grundland at the University of Cambridge. "That's something a
photographer would choose as a subject matter, and that's what we should
aim to convey with computers."Grundland also points out that the Graphics Turing Test does not specify what is conveyed in the virtual world scene. "If all that is there is a diffusely-reflectin g sphere sitting on a diffusely-reflectin g surface,
then we've been able to pass the test for many years now," he says. "But
Turing didn't mean for his vision to come true so quickly."
McGuigan agrees that realistic animation poses its own problems.
"Modelling that fluidity is difficult," he says. "You have to make sure
that when something jumps in the virtual world it appears heavy." But he
remains optimistic that animation software will be up to the task.
"Physical reality is about animation and lighting," he says. "We've done
the lighting now – the animation will follow."