WASHINGTON — Humanity has reached a bottleneck this century: Technical developments could cause catastrophic damage to the planet, or they could save humanity from its man-made quandary.
The future of civilization could be a dystopia of ruined ecosystems and malevolent machines, or a paradise of eternal life and intergalactic culture. At a symposium on the longevity of human civilization here at the Library of Congress Thursday (Sept. 12), several of the nation's leading scholars and futurists predicted what the coming centuries may bring.
"Everything I say today will probably be wrong," Scientific American journalist David Biello said at the start of the event. [Science Fact or Fantasy? 20 Imaginary Worlds]
Nonetheless, here are five of the speakers' science-fiction visions of the future.
1. Climate catastrophe
It's no surprise that rising carbon dioxide levels already pose a major threat to Earth's climate. Unless humans figure out a way to drastically limit their carbon footprint, the planet will continue to warm, extreme weather will become more frequent, and many species and human communities will be wiped out, said Ken Caldeira, an atmospheric scientist at the Department of Global Ecology of the Carnegie Institution for Science.
Can humans form a healthy, stable relationship with the biosphere?
"The answer is no," said Ken Caldeira, an atmospheric scientist in the department of global ecology of the Carnegie Institution for Science in Stanford, Calif.
Humans evolved as hunter-gatherers, sensitive to the needs of themselves and their close family and friends, Caldeira said. But now, humans have created a world dominated by technology, rather than nature, where problems extend to the global scale. If drastic measures to stem global climate change aren't taken, we don't know what effect it might have on human civilization, Caldeira said.
2. Bionic world
Biology has entered a kind of renaissance, from sequencing the human genome to developing lifesaving medical treatments.
Already, the world has seen mechanical hearts, prosthetic limbs and artificial organs, technologies that promise to restore human health and dramatically extend life span. But as these technologies become more democratized, black hat uses will surface.
The biggest threat individuals face is biohacking, said Seth Shostak, senior astronomer at the Search for Extraterrestrial Intelligence (SETI) Institute in Mountain View, Calif. Such biohacking includes everything from tinkering with the genome of a virus to make it deadly, to inserting information directly into the brain through an implant.
Perhaps humans will even develop an "ethics implant," said Jacob Haqq-Misra, a planetary climatologist at the Blue Marble Space Institute of Science. Such an implant would ensure people see eye-to-eye on the problems civilization faces.
3. Artificial intelligence
Scientists are passionately divided on the issue of whether humans will develop computers that are intelligent, or "thinking machines." Will HAL from "2001: A Space Odyssey" become a reality?
Science-fiction author Kim Stanley Robinson doesn't think so. "One thing we'll never understand is the human brain," said Robinson, author of the well-known "Mars" trilogy.
Scientists can only study the brain indirectly by measuring blood flow and electrophysiology, which is several magnitudes broader than the level of human thinking, Robinson said. Without understanding consciousness, how could humans create a machine capable of it? [Super-Intelligent Machines: 7 Robotic Futures]
Shostak disagrees. Humans didn't need to understand the details of how birds fly in order to develop airplanes, he said. So why should they need to understand the brain in order to develop intelligent computers? And, "once you have machine that can think, you can ask that to develop the next machine," Shostak said.
Taken to the extreme, some people believe intelligent machines could lead to "the singularity," a term popularized by inventor and futurist Ray Kurzweil to describe the point at which computers surpass the abilities of the human brain.
Kurzweil predicts this will happen by 2045, but Robinson and others are skeptical. Many people alive today will live to find out, Shostak said.
4. Spacefaring species
In 1969, humans landed on the moon. A few decades from now, humanity may be on Mars. And perhaps someday, Homo sapiens will roam the galaxy like the crew of the Starship Enterprise.
At the symposium, discussion ranged over whether colonizing the solar system could save humanity from destruction on Earth.
"One of the goals of space exploration should be to get some of us off the planet so we don't have to start from scratch if a major event happened on Earth," said Steven Dick, an astronomer, author and historian of science and the Library's 2014 chair in astrobiology. If a large asteroid hit Earth, humanity could be wiped out tomorrow, Dick said.
Yet while the technology for taking humans to space exists, people still rely heavily on an Earth-like environment. Traveling to space wouldn't inoculate humanity against catastrophes on Earth, Robinson said, and other speakers agreed. But it could serve to give people a perspective on the fragility of the "pale blue dot" on which humanity lives.
5. E.T. phones home
Few things would have as great an impact on humanity as discovering life elsewhere in the universe.
For the first time in history, humanity is poised to look for life on other planets. By necessity, humanity will be looking for life that resembles its own. NASA's Kepler mission successfully identified hundreds of planets orbiting at a habitable distance from their stars. And the SETI Institute is listening for radio signals that could signify technological civilizations are out there.
Some skeptics argue that if there were life, humans would have found it already. But a host of reasons could explain its absence. Maybe civilizations that have developed the technology to colonize other planets have already annihilated themselves. Or perhaps they're much more intelligent and obscuring themselves from humans.
Whatever the truth, if life does exist outside of Earth, the implications for human civilization would be enormous.
"Just knowing they're out there would be philosophically important," Shostak said.
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