Peter R. Holland is an English theoretical physicist, known for his work on foundational problems in quantum physics and in particular his book on the pilot wave theory and the de Broglie-Bohm causal interpretation of quantum mechanics.

Holland was educated at Hazelwick Comprehensive School in Crawley, West Sussex and at Imperial College. He did his Ph.D. on algebraic topological methods in physics under David Bohm at Birkbeck College.^{[citation needed]}

Holland has worked at the University of London, Universite Pierre et Marie Curie (Paris), Bristol UWE and the University of Oxford. He is an editor of Physics Letters A.^[1]

In 1993, Holland published his book “The Quantum Theory of Motion’’ in which he presented a comprehensive account of the causal interpretation of quantum mechanics initiated by Louis de Broglie and, in a more complete form, by David Bohm.

Recent work

Drawing upon numerical trajectory-based methods for solving the Schrödinger equation, and upon methods of hydrodynamics, Holland showed in 2004 how the time evolution of the wavefunction could be derived exactly from the dynamical evolution of a congruence of spacetime trajectories. The method achieves the same result as Richard Feynman's path integral formulation (the mapping of the initial wavefunction through time) but, instead of using Feynman's 'all possible paths' between two points, it employs at most one path. This is a considerable conceptual advantage in understanding quantum motion and is potentially a computational benefit too. Another difference with Feynman is that, while the trajectories do the job of evolving the quantum system in time, the initial wavefunction is integral to the trajectory dynamical equations, as it provides the initial density and the initial velocity. Using Riemannian geometry Holland formulated this method in very general terms that include as special cases quantum many-particle systems and spin. He has applied it to other field theories, such as electromagnetism and second-order wave equations.

Holland has published many peer-reviewed articles on the foundations of physics including the quantum potential, quantum hydrodynamics, quantum field theory, symmetries, hidden-variables theories, quantum back-reaction, quantum Hamilton-Jacobi theory, classical-like quantum systems, and the history of physics.