Editing List of physicists (section)

==K==
*[[Menas Kafatos]] – Greece, United States (born 1945)
*[[Takaaki Kajita]] – Japan (born 1959) Nobel laureate
*[[Michio Kaku]] – United States (born 1947)
*[[Theodor Kaluza]] – Germany (1885–1954)
*[[Heike Kamerlingh Onnes]] – Netherlands (1853–1926) Nobel laureate
*[[William R. Kanne]] – United States
*[[Charles K. Kao]] – China, Hong Kong, U.K., United States (1933–2018) Nobel laureate
*[[Pyotr Kapitsa]] – Russian Empire, Soviet Union (1894–1984) Nobel laureate
*[[Theodore von Kármán]] – Hungary, United States (1881–1963) aeronautical engineer
*[[Alfred Kastler]] – France (1902–1984) Nobel laureate
*[[Amrom Harry Katz]] – United States (1915–1997)
*[[Moshe Kaveh]] – Israel (born 1943) President of [[Bar-Ilan University]]
*[[Predhiman Krishan Kaw]] – India (1948–2017)
*[[Heinrich Kayser]] – Germany (1853–1940)
*[[Willem Hendrik Keesom]] – Netherlands (1876–1956)
*[[Edwin C. Kemble]] – United States (1889–1984)
*[[Henry Way Kendall]] – United States (1926–1999) Nobel laureate
*[[Johannes Kepler]] – Germany (1571–1630)
*[[John Kerr (physicist)|John Kerr]] – Scotland (1824–1907)
*[[Wolfgang Ketterle]] – Germany (born 1957) Nobel laureate
*[[Isaak Markovich Khalatnikov]] – Soviet Union (1919–2021)
*[[Jim Al-Khalili]] – U.K. (born 1962)
*[[Abdul Qadeer Khan]] – Pakistan (1936–2021)
*[[Yulii Borisovich Khariton]] – Soviet Union, Russia (1904–1996)
*[[Erhard Kietz]] – Germany, United States (1909–1982)
*[[Jack Kilby]] – United States (1923–2005) electronics engineer, Nobel laureate
*[[Toichiro Kinoshita]] – Japan, United States (1925–2023)
*[[Gustav Kirchhoff]] – Germany (1824–1887)
*[[Oskar Klein]] – Sweden (1894–1977)
*[[Hagen Kleinert]] – Germany (born 1941)
*[[Klaus von Klitzing]] – Germany (born 1943) Nobel laureate
*[[Jens Martin Knudsen]] – Denmark (1930–2005)
*[[Martin Knudsen]] – Denmark (1871–1949)
*[[Makoto Kobayashi (physicist)|Makoto Kobayashi]] – Japan (born 1944) Nobel laureate
*[[Arthur Korn]] – Germany (1870–1945)
*[[Masatoshi Koshiba]] – Japan (1926–2020) Nobel laureate
*[[Matthew Koss]] – United States (born 1961)
*[[Walther Kossel]] – Germany (1888–1956)
*[[Ashutosh Kotwal]] – United States (born 1965)
*[[Lew Kowarski]] – France (1907–1979)
*[[Hendrik Kramers]] – Netherlands (1894–1952)
*[[Sabine Kraml]] – Austria (born 1971)
*[[Serguei Krasnikov]] – Russia (born 1961)
*[[Adolf Kratzer]] – Germany (1893–1983)
*[[Lawrence M. Krauss]] – United States (born 1954)
*[[Herbert Kroemer]] – Germany (1928–2024) Nobel laureate
*[[August Krönig]] – Germany (1822–1879)
*[[Ralph Kronig]] – Germany, United States (1904–1995)
*[[Nikolay Sergeevich Krylov]] – Soviet Union (1917–1947)
*[[Ryogo Kubo]] – Japan (1920–1995)
*[[Daya Shankar Kulshreshtha]] – India (born 1951)
*[[Shaiwatna Kupratakul]] – Thailand (born 1940)
*[[Igor Vasilyevich Kurchatov]] – Soviet Union (1903–1960)
*[[Behram Kursunoglu]] – Turkey (1922–2003)
*[[Polykarp Kusch]] – Germany (1911–1993) Nobel laureate