How many fairy tales and science fiction works are associated with wonderful invisibility hats or some other tricks that make a person invisible. Is it possible to achieve invisibility and real life? Has any research been carried out in this direction? Our next issue is devoted to all these questions, telling about the so-called Philadelphia experiment with the American destroyer Eldridge. The text of the book was translated from the original language using an artificial intelligence program. For the most part, the translation of the text is of very high quality, but in some cases, due to the imperfection of the technology, there may be incorrect phrase translations in the text, as well as single words and expressions may not be translated.