Max Karl Wien (25.12.1866-24.02.1938) was a German physicist. He was born in Königsberg. He was assistant to W. C. Röntgen at the University of Würzburg, then professor at the Higher Technical School in Aachen, in 1904—11 in Danzig and in 1911—35 at the University of Jena.
His research concerned electromagnetism, physiological acoustics, the study of the properties of electrolytes and radio engineering. He studied high-frequency electromagnetic waves, spark discharges, coupled oscillations and the behaviour of electrolytes at high voltages. He improved spark transmitters. He built a number of instruments for measuring weak currents and the intensity of sound. In 1906 he proposed a special spark gap which prevented energy from returning from the aerial to the primary oscillatory circuit.