If This Is a Man to shape the book, giving it a clear sense of direction. In January 1947, the manuscript was rejected by Einaudi. The writers Cesare Pavese and Natalia Ginzburg thought it too early after the war for such an account. Levi managed to find a smaller publisher, De Silva, who printed 2,500 copies of the book, 1,500 of which were sold, mostly in Levi's hometown of Turin. In 1955, Levi signed a contract with Einaudi for a new edition, which was published in 1958. The initial printing of 2000 copies was followed by a second of the same size. An English translation
Melnikov distance formula_4. Suppose for formula_5 the system has a hyperbolic fixed point x and a homoclinic orbit formula_6 corresponding to this fixed point. Then for sufficiently small formula_7 there exists a "T"-periodic hyperbolic solution. The stable and unstable manifolds of this periodic solution intersect transversally. The distance between these manifolds measured along a direction that is perpendicular to the unperturbed homoclinc orbit formula_6 is called the Melnikov distance. If formula_9 denotes this distance, then formula_10. The function formula_11 is called the Melnikov function. Melnikov’s distance can be used to predict chaotic vibrations. In this method, critical amplitude is found by setting