The conceptual foundations of physics have been under constant revision from the outset, and remain so today. Discussion of foundational issues has always been a major source of progress in science, on a par with empirical knowledge and mathematics. Examples include the debates on the nature of space and time involving Newton and later Einstein; on the nature of heat and of energy; on irreversibility and probability due to Boltzmann; on the nature of matter and measurement during the early days of quantum theory; on the meaning of renormalization, and many others.

Today, insightful reflection on the conceptual structure utilized in our efforts to understand the physical world is of particular value, given the serious unsolved problems that are likely to demand, once again, modifications of the grammar of our scientific description of the physical world. The quantum properties of gravity, the nature of measurement in quantum mechanics, the primary source of irreversibility, the role of information in physics – all these are examples of questions about which science is still confused and whose solution may well demand more than skilled mathematics and new experiments.

Foundations of Physics is a privileged forum for discussing such foundational issues, open to physicists, cosmologists, philosophers and mathematicians. It is devoted to the conceptual bases of the fundamental theories of physics and cosmology, to their logical, methodological, and philosophical premises.

The journal welcomes papers on conceptual and foundations aspects of topics including (but not restricted to) special and general relativity, quantum theory, classical and quantum field theory, quantum gravity, unified theories, thermodynamics, statistical mechanics, cosmology.

Acceptance of a paper does not imply endorsement, but is restricted to high quality contributions judged relevant and interesting by the referees and the editors. Short papers can be included in the special category "Letters to the Editor". Articles that exceed 20 pages are considered only under justified motivation. The journal welcomes proposals for 'essay articles' that survey and review a topic or a problem, articles simply raising discussion points, suggestions for Special Issues reviewing novel developments, and book reviews. Please contact one of the editors for this.

• The leading journal for controversial issues concerning the foundations of modern physics
• Covers all topics in physical sciences, including quantum mechanics, special and general relativity, cosmology and string theory
• Dedicated Editorial Board headed by Carlo Rovelli
• 92% of authors who answered a survey reported that they would definitely or probably publish in the journal again