Can We Reduce CO2 Emissions While Sustaining Economic Growth?

In the latest G8 meeting, leaders of developed countries settled on reducing GHG emissions by 50% by 2050 although they were criticized for not setting any mid-term targets. However, even meeting this 50% reduction target seems difficult at the moment. Scientists and researchers opine that CO2 emissions have to be cut by 80% (base year 2000) by mid-century if we are to avoid any serious climatic issues. However, most of the developing and underdeveloped nations subsidize gasoline, which accounts for a large proportion of carbon emissions. And if these nations do not give subsidies, they may not be able to maintain their economic growth. Jeffery Sachs, director of Columbia University's Earth Institute, mentioned in Scientific American magazine that we cannot cut CO2 emissions while maintaining global economic development with the contemporary technologies we have now. So the answer may be in technology.