The power of computer processing could one day solve the riddle of life's origin.
Scientists think life appeared about 4 billion years ago, and ancient rocks on Earth can give us some idea of what the environment was like. Life may have originated in an ocean rich in chemicals. This primordial soup may have been simmering, or it may have been zapped by lightning. Certainly energy of some sort must have helped drive a simple chemical system into a more complex state. But the clues are few, and the picture remains hazy.
Enter the Evogrid, a computer creation concept that would be a digital version of the primordial soup. The EvoGrid was dreamed up by a group of international advisors and Bruce Damer, the founder of a research company that creates 3-D spacecraft and mission simulations for NASA and the space community. Damer and his chief architect, Peter Newman, are developing the EvoGrid concept by adapting GROMACS, a powerful open source molecular dynamics simulator originally developed at The University of Groningen in the Netherlands.
Each virtual particle within the Evogrid's simulated liquid soup will have particular physical properties, and will behave accordingly.
"We will be constructing a model of a 'toy universe,' which has approximate properties of the early oceans on Earth," says Damer.
With a laundry list of basic physical properties entered into the starting parameters, the simulation would allow artificial nature to take its course. Interactions and connections between particles should occur, and ever higher levels of complexity may arise from the most basic elements.
Much like SETI@home's screen saver, which enables computers at home to search for signals of extraterrestrial life within volumes of astrophysical data, the Evogrid is conceived to have volunteer computers become part of an interconnected grid for maximum processing capacity. Damer hopes to eventually get a million computers hooked into the grid.
These computers would receive data from the EvoGrid simulation engine. The simulation would essentially consist of a vast virtual ocean of interacting numbers that would model the time before complex life forms emerged. To know whether self-organization is occurring, the program would look for persistent patterns within the data.
"If a vesicle, or a ball of particles has formed, you would be able to detect that," says Damer. "If a string of particles began to replicate, that would be easy to track, or if particles began to combine in a long chain of reactions, that would be important but tougher to recognize."
It is thought that some combination of a lipid container (vesicle), strings of molecules (genomes) and metabolic reactions led to the development of life. The Evogrid won't produce visual images of the combined effort of all the linked computers, because it would slow the processing down too much. However, home users would see a visualization of what is being observed in their own small patch of the EvoGrid.
Damer notes that present-day computer simulations run much more slowly than chemical reactions, but he anticipates that in the next 20 to 40 years, with the help of millions of microprocessors, an entire cell could be simulated in cyberspace.
"Nils Baricelli wrote an artificial life program for the first modern computer in 1953, and to some extent we haven't gone much further than his original experiment," says Damer. "We shall see how far the EvoGrid can go, using millions of the descendents of the original Von Neumann machine."
Tinkering with life
Damer envisions two possible versions of Evogrid: a hands-off "Origins" version, and an experimental "Intelligent Designer" edition that would allow people to tinker with the simulation. Damer says the ID edition of Evogrid could include a "miracle module" that would allow users to play God in their attempts to create proto-life. The Origins edition would be the focus of the science, however, with strict controls to shield the experiment from any guiding human influence.
Damer muses that "in its ultimate incarnation, a much more powerful EvoGrid would allow us to pose the question: where in this universe or others might life exist and at what level of complexity?" Damer thinks an EvoGrid tuned for SETI and astrobiology could be used to simulate extraterrestrial environments and address the question of whether life could have emerged there.
Even if the EvoGrid managed to generate some virtual but convincing life forms, either through random or directed means, "the numbers will always be numbers," says Damer. "As Baricelli wrote over fifty years ago, they will never be living organisms."
But Damer dreams big, and he thinks someday the creatures generated by the Evogrid could be re-created chemically. A virtual scanner could be devised to break down the computer-based creature into its digital body parts, and then that information could be used to try to build the same creature out of real chemistry in the lab. Of course, this step of the experiment would rely on technology that does not currently exist. "Life is more than the sum of its parts, and you can't just throw the necessary chemicals together and expect a life form to emerge," Damer says.
However, researchers are hard at work trying to recreate all the biochemical steps necessary to synthesize a kind of proto-life in the lab, so perhaps this possibility is not too far over the horizon.
Looking even farther into the future, Damer thinks that far more advanced EvoGrids, paired with "ChemoGrids," could be used to create a new genesis of cyber-physical life forms to colonize asteroids, or to terraform Mars into a more habitable planet for humans. He notes that "evolution within an adaptively-tuned living system is the only mechanism powerful enough to make a place outside of the Earth habitable for us."
Damer expects that other intelligent civilizations in the universe probably harness the power of evolution to solve difficult problems such as creating habitable zones to colonize. "This is a common theme in science fiction, but science fiction tells us what could be possible someday," he adds. "The way for us to get there is to start with simulation and ride the wave of ever greater computing power."