The Next Millennium and the Remote Future

The Next Millennium and the Remote Future

Lecture 47

Is it possible that the dangerous knowledge that accumulates within a species like ours that’s capable of collective learning is bound to eventually outweigh the more creative knowledge that such species generate? Or is it simply that such a species is eventually bound to construct societies of such complexity that they’re not sustainable?

Now we return to larger spatial and temporal scales. We consider rst the next millennium. Then we consider the rest of time, asking about the future of the Earth, the galaxy, and the Universe as a whole. Oddly, we will see that it is easier to discuss the remote future than the next millennium. On the scale of a millennium or so, we have far more questions than answers! Human societies are so complex that, even if we can identify some trends, we know of none that are certain to continue for more than a few decades. All we can really do is to play with different scenarios.

Some scenarios are disastrous for humans and perhaps for the entire biosphere. In A Canticle for Leibowitz (1st published in 1959), Walter M. Miller imagined a future in which nuclear weapons were developed and used, then redeveloped and used again. Is this the fate of all species capable of “collective learning”? Is there a necessary limit to collective learning? Could that be why we have failed to detect other species like ourselves?

Geologists now understand that the Earth’s history has been interrupted by periodic asteroid impacts such as those that killed off the dinosaurs. Though astronomers can now keep an eye on potentially dangerous objects, we do not yet have the means to protect ourselves adequately from such impacts.

Some scenarios are more optimistic. Perhaps, after a near brush with disaster (such as the regional nuclear wars described in the future histories written by Wagar as well as Stableford and Langford), we will avoid the fate of Easter Island. We will slow consumption levels and nd new ways of living that can be satisfying without putting excessive pressure on the environment. If our ancestors avoid disaster, the “Modern era” may turn out to be the prelude to

an entire new epoch of human history. Innovation may generate sustainable technologies that we can barely imagine. They may include new energy sources (such as hydrogen fusion) and biotechnologies that create new food sources, eliminate most forms of ill-health, and prolong human life. New social structures may include mechanisms for reducing violent con ict and generating more sustainable notions of progress and well-being.

In reality, of course, the future will probably fall between these extremes. What new things will we learn? Here are areas where there could be profound scienti c and technological breakthroughs in the next millennium. Quite soon, we may nd evidence for the existence of planets similar to the Earth. Will we also nd evidence for the existence of life elsewhere in the Universe? At present, the speed with which bacterial life appeared on our planet makes it seem likely that life of some kind is widespread.

We are less likely to nd evidence for creatures like us, capable of collective learning. On Earth it has taken almost 4 billion years to evolve such a species. And a lot of luck was involved. In a famous study of the Cambrian fossils of the Burgess Shale (in the Canadian Rockies), Stephen Jay Gould argued that biological evolution can take many utterly different pathways. On the other hand, Simon Conway, another specialist on the Burgess Shale fossils, has argued that the number of evolutionary pathways may be limited, which makes the evolution of species like us more probable. If our descendants survive disaster, are there new thresholds of complexity waiting to be crossed? Perhaps, like eukaryotic cells in the Cambrian era, they will become so interdependent that they will turn into a single Earth-spanning organism, capable of managing “Gaia.”

Our descendants might start migrating again, leaving this Earth just as our ancestors migrated from Africa and through the Paci c. Many of the technologies already exist for migration to the planets and moons of our solar system. But we have none of the technologies needed to reach other star systems. If our descendants do migrate to distant star systems, will they create a vast archipelago like the colonies of Polynesia? If so, will collective learning occur at stellar scales? Or will the distances be so huge that human communities will become isolated culturally, and even genetically? If so, our species will split by allopatric speciation into numerous closely related

successor species, just like the Galapagos nches. Will that mark the end of human history?

At larger scales we return to slower and simpler processes, such as the evolution of the Earth, the Sun, and the Universe. These we can predict with more con dence. Studying the movement of tectonic plates hints at what the Earth will look like in 100 or 200 million years’ time. The Atlantic will widen; the Paci c will narrow, bringing Asia and North America together; and eventually a new supercontinent will emerge. Los Angeles will slide north and join Canada.

Our Sun is about halfway through its life. In 4–5 billion years it will run out of hydrogen, collapse, and then expand again to form a “red giant.” The Earth will be vaporized. Eventually, the Sun will cool and shrink, becoming a “black dwarf.” In its retirement, it will keep cooling for countless billions of years. Our galaxy, the “Milky Way,” is on a collision course with its neighbor the Andromeda galaxy. The two will collide as our Sun enters its death throes, gliding through each other gracefully, though gravity will introduce some turbulence as they do so.

How will the Universe evolve? One idea, popular in the late 20th century, was that the gravitational pull of all the matter and energy in the Universe would eventually slow expansion until the Universe began to collapse in on itself. Time would reverse, and the Universe would collapse in a “big crunch,” to be followed perhaps by a new “big bang,” which would create a new Universe.

In the late 1990s, astronomers found that the rate of expansion of the Universe is actually increasing. We do not yet know why. But this suggests the Universe will keep expanding forever. What will that mean? Eventually, all stars will use up their fuel and die. The Universe will darken, and black holes will graze on what’s left for countless billions of years. The space between

In the late 1990s, astronomers found that the rate of expansion of the Universe is actually increasing. We do not yet know why.

objects will increase, and temperature differentials will narrow. With smaller energy differentials to drive complexity, the Universe will become simpler and more boring. The second law of thermodynamics will have triumphed over complexity. The Universe will continue to get more uninteresting for as many billions of years as there are sand grains on all the beaches and deserts of the Earth. And so on, forever and ever.

Where does that leave us? What is our place in this huge story? The last lecture will recapitulate the story of big history and touch on these large issues of meaning.

Essential Reading

Supplementary Reading

Questions to Consider

Christian, Maps of Time, chap. 15. Prantzos, Our Cosmic Future.

Miller, A Canticle for Leibowitz. Stableford and Langford, The Third Millennium. Stearns, Millennium III, Century XXI. Wager, A Short History of the Future.

1. Are there any reasonable predictions we can make about the next 1,000 years?

2. What can we reasonably say about the future of the Universe?