All applications are submitted online at the Graduate Studies Office. Application fee waivers are also requested and processed through the application process.
http://www.gradoffice.caltech.edu/admissions
Important graduate admissions update for Fall 2025 applications: The GRE general test is optional and the GRE physics subject test is strongly recommended.
GRE scores are not a required component of the application. But for applicants who decide to submit GRE scores, they will be considered in our evaluations. Admissions decisions are based on many factors including academic and research performance, letters of recommendation and personal statements. Physics GRE scores do not outweigh any of these factors, but they may provide another way for an applicant to demonstrate a strong physics background.
The Physics Graduate Admissions Committee will review the applications and recommendations for admission are sent to the Graduate Studies Office. The official offer of admission comes from the Graduate Studies Office via email though the online application system. Students must respond to our offer by April 15 th .
Please visit the Graduate Office for Frequently Asked Questions regarding admissions.
What are the degree requirements for admission to the physics graduate program?
The physics department does not usually consider applicants who already possess a Ph.D. Also, the M.S. degree is not necessary for admission into this program. Most of the applicants to this program are expecting the B.S. or B.A. degree to be awarded by their undergraduate institution after admission to this graduate program has been offered. Note that an official transcript documenting the award of an undergraduate degree is required prior to enrollment in the physics graduate program at Caltech.
What level of undergraduate preparation is necessary for admission?
Mechanics at about the level of Goldstein's Classical Mechanics; electromagnetism at the level of Reitz and Milford's Foundations of Electromagnetic Theory; atomic and nuclear physics at the level of R.B. Leighton's Modern Physics; introductory quantum mechanics at the level of Dicke and Wittke's Introduction to Quantum Mechanics, and advanced calculus at the level of T.M. Apostol's Mathematical Analysis.
Should I apply to Physics or Astronomy?
There is a considerable amount of research in astrophysics carried out in the Physics Department. It is not unusual for faculty in Astronomy to supervise Physics students or for Astronomy students to find astrophysics advisors in the Physics Department. Students who are not sure whether they want to work in astrophysics or in other areas of physics should apply to the Physics Department. Students who already know they want to work in nuclear and particle astrophysics, gravitational-wave astrophysics, or on space-based projects in cosmic-ray, gamma-ray, X-ray or infrared astronomy, should apply to the Physics Department. Research on ground-based submillimeter, infrared, optical and radio astronomy (including instrumentation) goes on in both departments. There are students in theoretical astrophysics from both Physics and Astronomy, although most come from Physics.
Should I apply to Physics or Applied Physics?
The Applied Physics Department is part of the Division of Engineering and Applied Science. The Physics Department is part of the Physics, Math, and Astronomy Department. There is some overlap between the activities in Physics and those in Applied Physics. Research in Physics is aimed more toward the understanding of fundamental principles, as opposed to direct applications. Since there is overlap, sometimes Physics students work with Applied Physics professors to attain a PhD in Physics.