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==Falsifiability==

==Falsifiability==

There is much debate on whether string theory is truly scientific. Under the [[positivist]] philosophy, models must be falsifiable (i.e. it must be possible to define an experiment which could contradict the theory) for them to qualify as science, and then they must survive these tests. In more general terms, a model is not scientific unless we can use it to make predictions about the world we observe, and it is consistent with those predictions. String theory has yet to yield a particular definitive test, or to produce any models that resemble any known particles or forces.

There is much debate on whether string theory is truly scientific. Under the [[positivist]] philosophy, models must be falsifiable (i.e. it must be possible to define an experiment which could contradict the theory) for them to qualify as science, and then they must survive these tests. In more general terms, a model should be able to make predictions about the world we observe. String theory has yet to yield a particular definitive test, or to produce any models that resemble any known particles or forces.

The discovery of [[dark energy]] in 1998 was a particularly damaging blow to string theory. It was just the sort of thing that string theorists hoped to explain, and yet string theory cannot explain it. As of today, string theory has attracted strong intetrest among theorists but has not suggested any critical experiments.  

The discovery of [[dark energy]] in 1998 was a particularly damaging blow to string theory. It was just the sort of thing that string theorists hoped to explain, and yet string theory cannot explain it. As of today, string theory has attracted strong intetrest among theorists but has not suggested any critical experiments.  

Some string theorists, such as Leonard Susskind, say that string theory may not be testable but may still provide insights on multiple universes. His recent book is ''The Cosmic Landscape: String Theory and the Illusion of Intelligent Design''.

Some string theorists, such as Leonard Susskind, say that string theory may not be testable but may still provide insights on multiple universes. His recent book is ''The Cosmic Landscape: String Theory and the Illusion of Intelligent Design''.

==Further reading==

==Further reading==

* Smolin, Lee.  ''The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next '' (2007)[http://books.google.com/books?id=z5rxrnlcp3sC&pg=PA99&lpg=PA99&dq=string+theory+smolin+%22brief+history%22&source=bl&ots=SQ9FOy7Xzc&sig=wdybggr1pcZ_OGGVzjQOb4S8R4E&hl=en&ei=HLkHSuX-ApPstgOw39zcAQ&sa=X&oi=book_result&ct=result&resnum=1 part 2 online]

* Smolin, Lee.  ''The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next '' (2007)[http://books.google.com/books?id=z5rxrnlcp3sC&pg=PA99&lpg=PA99&dq=string+theory+smolin+%22brief+history%22&source=bl&ots=SQ9FOy7Xzc&sig=wdybggr1pcZ_OGGVzjQOb4S8R4E&hl=en&ei=HLkHSuX-ApPstgOw39zcAQ&sa=X&oi=book_result&ct=result&resnum=1 part 2 online]