Based on archival documents, original articles, books and memoirs of contemporaries, the book details the ideological campaign to combat physical idealism in Soviet physics. During the campaign, new physics - relativity and quantum mechanics - was declared alien to dialectical materialism and, therefore, vicious. This campaign took place against the backdrop of the fight against cosmopolitanism, and all physical idealists were also declared cosmopolitans, since they often published their works in foreign magazines. The largest Soviet physicists: Kapitsa, Landau, Fock, Frenkel, Ioffe, Markov, Mandelstam and other scientists who defended the new physics were sharply criticized in print and at meetings, "bullying" and "defaming" by individual Soviet philosophers and "philosophers" physicists. A separate section is also devoted to the ideological struggle against "alien ideas" in chemical science. The publication is addressed to physicists, chemists, historians of science and everyone who is not indifferent to the fate of scientific research in our country.