Quite simple: a technological civilization cannot outlast its energy resource base. Once this resource is spent, technological civilization will be forever beyond our grasp.
From "The Peak of World Oil Production and the Road to the Olduvai Gorge" by Richard C. Duncan, Ph.D.:
Although all primary sources of energy are important, the Olduvai theory postulates that electricity is the quintessence of Industrial Civilization. World energy production per capita increased strongly from 1945 to its all-time peak in 1979. Then from 1979 to 1999 - for the first time in history - it decreased from 1979 to 1999 at a rate of 0.33%/year (the Olduvai 'slope', Figure 4). Next from 2000 to 2011, according to the Olduvai schema, world energy production per capita will decrease by about 0.70%/year (the 'slide'). Then around year 2012 there will be a rash of permanent electrical blackouts - worldwide. These blackouts, along with other factors, will cause energy production per capita by 2030 to fall to 3.32 b/year, the same value it had in 1930. The rate of decline from 2012 to 2030 is 5.44%/year (the Olduvai 'cliff'). Thus, by definition, the duration of Industrial Civilization is less than or equal to 100 years.
The Olduvai 'slide' from 2001 to 2011 (Figure 4) may resemble the "Great Depression" of 1929 to 1939: unemployment, breadlines, and homelessness. As for the Olduvai 'cliff' from 2012 to 2030 - I know of no precedent in human history.
Governments have lost respect. World organizations are ineffective. Neo-tribalism is rampant. The population is over six billion and counting. Global warming and emerging viruses are headlines. The reliability of electric power networks is falling. And the instant the power goes out, you are back in the Dark Age.
In 1979 I concluded, "If God made the earth for human habitation, then He made it for the Stone Age mode of habitation." The Olduvai theory is thinkable.
http://www.oilcrisis.com/duncan/olduvai2000.htmAlso see "The Olduvai Theory: Sliding Towards a Post-Industrial Stone Age":
Back in 1989 I became deeply depressed when I concluded that our greatest scientific achievements will soon be forgotten and our most cherished monuments will crumble to dust. But more so, I knew that my children would feel the pressure, and will likely suffer. That really hurt.
In time however, my perspective changed. Now I just treat the Olduvai theory like any other scientific theory. Nothing personal. Each year, I gather the data. Update Figure 2. And watch the theory unfold. Let the chips fall. What else?
Still, the impending Post-Industrial Stone Age is a tragedy because it really isn't inevitable. There's no absolute reason why we couldn't live in material sufficiency on this planet for millions of years. But prudence isn't our forte. "Even our success becomes failure." And, in a way, it's not our fault. Long ago Natural Selection dealt us a bad hand—we're sexually prolific, tribal, short-term and self-centered. And after thousands of years of trying, Culture hasn't changed that. And there is no sign that She will.
Backward to the future. Forward to the past. Almost perfect symmetry.
http://dieoff.org/page125.htm"There is enough energy remaining in the world right now for us -- the people -- to take control and ease ourselves into a democratic, egalitarian, stable-state society.
Or there is enough energy for the elite to build a feudalistic, fascist, police state with themselves at the top. This is the choice facing us right now, and this is what is truly at stake." - Dale Allen Pfeiffer
http://www.fromthewilderness.com/free/ww3/080802_oil_empire.html