Jainendra K. Jain, an Indian-American physicist, is the Evan Pugh University Professor, Erwin W. Mueller Professor of Physics, and Holder of Eberly Family Chair of Physics at the Pennsylvania State University. He received the Oliver E. Buckley Prize of the American Physical Society in 2002, was elected to the National Academy of Sciences in 2021, and was selected Foreign Fellow of the Indian National Science Academy in 2024.^[1] Jain is known for his theoretical work on quantum many body systems, most notably for postulating particles known as Composite Fermions.

Jain received his primary, middle and high school education in a government school in a rural village called Sambhar, Rajasthan,^[2] located at the eastern margin of Thar desert in India. He received bachelor's degree at Maharaja College, Jaipur,^[3] his master's degree in physics at Indian Institute of Technology Kanpur^[3] and PhD at the Stony Brook University,^[3] where he worked with Profs. Philip B. Allen and Steven Kivelson. After post-doctoral positions at the University of Maryland and the Yale University he returned to the Stony Brook University as a faculty in 1989. In 1998 he moved to the Pennsylvania State University^[1].

Jain is a quantum physicist in the field of condensed matter theory with interests in the area of strongly interacting electronic systems in low dimensions. As the originator of the exotic particles called composite fermions, he pioneered and developed the composite fermion theory of the fractional quantum Hall effect and unified the fractional and the integral quantum Hall effects. His writings include a monograph Composite Fermions,^[4] published in 2007 by the Cambridge University Press. He co-edited with Bertrand Halperin a book Fractional Quantum Hall Effects: New Developments,^[5] published in 2020 by World Scientific.

• Elected Foreign Fellow of the Indian National Science Academy, 2025.^[6] Citation: "Prof Jain predicted a new class of exotic particles, which he named “composite fermions,” and explained the fractional quantum Hall effect as the integer quantum Hall effect of composite fermions. In doing so, he accomplished a unification of the fractional and the integer quantum Hall effects, two Nobel prize winning phenomena. His discovery of composite fermions is recognized as a singular and transformative development in the realm of condensed matter physics."
• Appointed Holder of Eberly Family Chair, Pennsylvania State University, 2023.^[1]
• Elected to National Academy of Sciences, 2021.^[7]
• Appointed Evan Pugh University Professor, named after the first President of Pennsylvania State University, 2012.^[8]
• Fellow, American Association for the Advancement of Science, 2011.^[1]
• Distinguished Alumnus Award of IIT Kanpur, 2010.^[1]
• Elected member of American Academy of Arts and Sciences, 2008.^[9] Citation: "Evan Pugh University Professor and Erwin W. Mueller Professor of Physics. Predicted that electrons in the factional quantum Hall effect regime capture quantized vortices to form new particles, which he named composite fermions. Subsequently observed, composite fermions brought clarity to the subject and spawned new lines of theoretical inquiries and elegant new experiments."
• Oliver E. Buckley Prize awarded by the American Physical Society for a most important contribution to the advancement of knowledge in Condensed Matter Physics, 2002, along with Nicholas Read and Robert Willett.^[10] Citation: "For theoretical and experimental work establishing the composite fermion model for the half-filled Landau level and other quantized Hall systems"
• Appointed Erwin W. Mueller Professor of Physics, Pennsylvania State University, 1998.^[1]
• Fellow of the American Physical Society, 1997.^[1] Citation: "For the "Composite Fermion" theory of the fractional quantum Hall effect."
• Fellow, Alfred P. Sloan Foundation, 1997.^[1]
• Fellw, John Simon Guggenheim Memorial Foundation, 1991.^[1]