Singapore's Wie Qi Katelin Heng competes in the individual all-around qualification round during the 39th FIG Rhythmic Gymnastics World Championships at the Arena Armeets in Sofia (Arena Armeec hall) on September 14, 2022. (Photo by Nikolay Doychinov/AFP Photo)

A woman wearing in face mask to curb the spread of COVID-19 passes street's cafe in Kyiv, Ukraine, Friday, October 22, 2021. Coronavirus infections and deaths in Ukraine have surged to all-time highs amid a laggard pace of vaccination, which is one of the lowest in Europe. (Photo by Efrem Lukatsky/AP Photo)

Elementary school sumo wrestler Kyuta Kumagai competes in a sumo ring at a regional tournament of Junior Olympic Cup All-Japan Elementary School Sumo Championship in Kawasaki, south of Tokyo, Japan, October 17, 2021. (Photo by Kim Kyung-Hoon/Reuters)

France's Alize Cornet falls down during her women's singles tennis match against Kazakhstan's Elena Rybakina on the fourth day of the 2023 Wimbledon Championships at The All England Tennis Club in Wimbledon, southwest London, on July 6, 2023. (Photo by Glyn Kirk/AFP Photo)

An Iranian soldier guards two German tourists near the Iranian-Turkish border during World War II. Since the British occupation of Iran, all Axis nationals are being expelled from the country. (Photo by Three Lions/Getty Images). Circa 1941

One of the last incoming trains arrives outside the main train station after Deutsche Bahn cancelled all train traffic in Germany due to heavy storms, Frankfurt, Germany, Thursday, January 18, 2018. (Photo by Michael Probst/AP Photo)

A worker assembles a sеx doll at the WMDOLL factory in Zhongshan, Guangdong Province, China, July 11, 2018. The factory has over 200 full-time workers, all dolls are handmade and each requires the cooperation of at least five workers. (Photo by Aly Song/Reuters)

Sandrine Kerfante has had a fascination with “doubles” ever since meeting her mother’s twin as a child. In 2012, this lifelong captivation inspired her to create a blog called twin-niwt, which celebrates photographs of doubles in all their forms. “I’m fascinated by the idea of the duo, repetition, symmetry, reflection, mirror games and all the symbolism associated with it”, she says. “I think it’s a topic often present in photography, more or less consciously”. (Photo by Sandrine Kerfante/The Guardian)