Yes, it is possible to do research in theoretical physics without studying applied physics. Theoretical physics is a branch of physics that focuses on developing mathematical models, theories, and frameworks to explain and predict the behavior of physical systems. It involves abstract thinking, mathematical reasoning, and the formulation of hypotheses.
While studying applied physics can provide a strong foundation and practical understanding of physical phenomena, it is not a strict requirement for pursuing theoretical physics research. Theoretical physicists often focus on fundamental concepts and explore the underlying principles of the universe, such as quantum mechanics, relativity, particle physics, and cosmology.
To conduct research in theoretical physics, a strong background in mathematics is essential. Mathematical methods, such as calculus, differential equations, linear algebra, and group theory, are commonly used in theoretical physics research. Additionally, a deep understanding of physics concepts and theories is crucial, which can be obtained through dedicated study of theoretical physics itself.
It is important to note that interdisciplinary collaboration and knowledge exchange between different branches of physics, including applied and theoretical physics, can often lead to valuable insights and advancements. However, it is indeed possible to pursue research in theoretical physics without specifically studying applied physics.