For my part, I imagine the world in fifty years with economic and environmental problems. However, I think there will be huge progress in medicine, astronomy, and robotics.
A problem that is often debated nowadays is that of the greenhouse effect. Global warming will be all the more important as time goes by if nobody do anything. If humans continue to chop down forest trees for timber or to make room for farm land, and if the industries contribute to the greenhouse effect, we can expect the sea level to rise. Consequently, there will be floods, less land for agriculture, and maybe starvation or civil war.
But in fifty years, if some people can make the world population aware of nature's fragility, the world might be asafer place to live.
With technological advances, we hopefully will understand the needs of our planet better. In space, satellites and space stations will be more help us to understand glacier formation and forest evolution. Agricultural experiments will contribute to the production of genetically modified food. The effect of technology upon our life styles will result in the increase of computer use and robots in our lives. Transportation will be automatic and will not emit greenhouse gases.
I firmly believe that the government will encourage people to be more aware of nature. People should stop using cars and start usings public transportation. So we must refrain from using our cars.
So to sum up, the world would be a better place to live if everyone assumed their responsibilities.