How much time is left to the extinction of the human race? One of the possible answers is provided by a mathematical study of the '70s. Maybe.

What if it would be possible to calculate the time that separates us from the extinction of the human race with a mathematical equation? Fascinating hypothesis, no doubt. The fans of the television series Lost'' should know this supposition well, as the events of the series concern a mysterious sequence of numbers drawn from a Sardinian mathematician appointed to find out when the end of the world would take place. We spoke with the mathematician and logician Piergiorgio Odifreddi, starting from far away, from the mathematical structure of the universe and the relationship between mathematics and images.

**The recent demonstration of the existence of the gravitational waves has raised great interest in the popular visual culture. What mathematical aspect of the universe fascinates you the most? **

What fascinates me the most is not a particular example of the application of mathematics to the description of the Universe, but the fact that math is the language with which all the scientific descriptions are expressed. Without mathematics, the theoretical disciplines, as physics for example, would not possible, and without mathematics, quantitative previsions, that are what distinguish Science from all the other descriptions of universe, could not be made.

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**In Science there's an important creative and visual element that is often forgot or ignored. As a teacher and popular personality, what is your relationship with this dimension?**

In many of my books I’ve used pictures to illustrate math and in particular in the geometric trilogy of "There is room for all”; "A way out"; "Down with Euclide"; and the "museum of the numbers". I tried to show how art and nature often concretely illustrate the notions and the abstract results of mathematics.

**During the period of Cold War, The Security Committee of the United Nations ordered to the sardinian mathematician Enzo Valenzetti the study of an equation that could predict the time left to the extincion of human being. Is the so-called Equation of the end of the world an example of “fake-mathematics” or is it something scientifically valid? What is the distinguish between a scientific prevision and a prophecy? **

To be honest, there is no "Valenzetti Equation", that is an invention of the television series “Lost”. It does exist instead a true " Doomsday equation”, that has been very much discussed and that tries to calculate how many human beings composed humanity in its history.

Obviously this kind of equations must be handled carefully, as they are just approximate calculations, that extremely simplify the problems that they try to solve, but they can give a general idea of a kind of final solution. The results obtained from these approximations can be more and more elaborated and precise and this is exactly the procedure of science.