Grichka and Igor Bogdanoff, Twins in an Uneasy Spotlight, Die at 72

It was in Saint-Lary-Soulan, a ski resort in the French Pyrenees near Spain’s border, that Grégoire Yourievitch Bogdanoff and Igor Yourievitch Bogdanoff, both of whom went by the surname Bogdanoff, were born on August 29, 1949.

Itinerant painter Youri Ostasenko-Bogdanoff claimed to be descended from a Tatar prince and had fled Russia as a child, according to the family legend.

They were raised by Bertha Kolowrat-Krakowska, their maternal grandmother, a former Bohemian countess who lost her title after an affair with Black American tenor Roland Hayes while touring France.

Maria Dolores Franzyska Kolowrat-Krakowska, the twins’ mother, was the daughter of the Kolowrats.

Igor’s first marriage, to the Belgian aristocrat Ludmila d’Oultremont, was dissolved after only a few months of marriage. In 2009, at the Château de Chambord in the Loire Valley, he married Amélie de Bourbon-Parme, a model and direct descendant of Louis XIV. In 2016, they broke up.

François Davant, a half-brother, and Laurence, Géraldine, and Véronique Bogdanoff, all sisters, predeceased the brothers. Dmitri, Igor’s son from his second marriage to actress Geneviève Grad, as well as daughters Sasha and Anna-Claria and a son Wenceslas, all of whom he had with his first wife, survive.

Early on, the Bogdanoffs claimed to be geniuses and to have scored 190 on I.Q. tests, which they said they had taken as children. École Pratique des Hautes Études, also known as Sciences Po, is where they earned their master’s degrees in applied mathematics.

Immediately following the end of “Temps X” in 1987, the Bogdanoffs published “Dieu et La Science” (1991), a study of the relationship between religion and science. An astrophysicist at the University of Virginia sued the authors, claiming that they had plagiarised one of his books for their best-seller.

In 1995, the brothers settled out of court, having begun their graduate studies in the meantime. They claimed to be driven by a fascination with the “initial singularity,” the point in time and space just before the Big Bang when everything was compressed into an infinitely dense point.