Samuel Dwight Gehman (December 7, 1903 – June 1, 1992) was a Goodyear physicist noted for development of a modulus-based measurement of rubber's glass transition temperature.

[4] He completed his doctoral dissertation in 1929 on the topic Reflection of Soft X-rays.

[8] He managed physics research at Goodyear's research division and was renowned for developing the Gehman low-temperature twist test, which gave laboratories convenient and precise low-temperature stiffening measurements of rubber compounds.

[10] In 1972, Gehman was listed at 10th out of the 100 top contributors to the world's rubber literature published between 1932 and 1970.

[11] Gehman retired in 1968 following 40 years with Goodyear Tire & Rubber Co.