Acceptance of peak oil is far from universal, and the only reliable way to identify its existence will be in retrospect. One alternative scenario is that global production will eventually follow an 'undulating plateau' for one or more decades before declining slowly.

Having accurately predicted the date of peak production in the US petroleum industry, which occurred in 1970, M. King Hubbert, who devised the theory, forecast that the world peak would occur in 1995 'if current trends continue'. Various subsequent predictions have been made as trends have fluctuated in the intervening years. Two milestones have passed, however. The peak of world oilfield discoveries occurred in 1965 and, due world population growth, production per capita peaked in 1979.

The effects of peak oil could be mitigated through conservation and switching to alternative fuels or unconventional oil sources. Such changes would bring their own challenges, ranging from the need to development alternative technologies to potential increases in greenhouse gas emissions.

• The Power of Community: How Cuba Survived Peak Oil is a documentary film which details Cuba's efforts to recover from the 1990s economic crisis known as the Special Period?

• The Geysers (pictured), north of San Francisco, California, is the largest geothermal power development in the world?

• The International Energy Agency was founded in 1974 by the Organisation for Economic Co-operation and Development (OECD) in the wake of the 1973 oil crisis?

• Indian Railways has started to use Jatropha oil, blended with diesel fuel in various ratios, to power its Diesel locomotives?

• The South Wales Gas Pipeline is the largest high pressure gas pipeline in the United Kingdom?

• The Presbyterian Church (USA) was the first major religious denomination in the world to call on its followers to become carbon neutral?

• There was partial meltdown at the Three Mile Island nuclear power plant in 1979?

• A hybrid electric vehicle achieves better fuel economy than a conventional vehicle without being hampered by the limited range of an electric vehicle?

Fermi was well-known for his simplicity in solving problems. Whenever possible, he avoided complicated mathematics and obtained quick results based on order of magnitude estimates. Fermi also meticulously recorded his calculations in notebooks, and later used to solve many new problems that he encountered based on these earlier known problems.

After accepting the 1938 Nobel Prize in Stockholm, Fermi immigrated to New York with his family to escape the anti-Semitic laws of Fascist Italy, as his wife Laura was Jewish.

After working at Columbia University, Fermi went to the University of Chicago and began studies that led to the construction of the world's first nuclear reactor Chicago Pile-1 (CP-1). The first artificial, self-sustaining, nuclear chain reaction was initiated within CP-1, on December 2, 1942.