Introduction: Conceptual issues in quantum field theory Part I. Philosophers' Interests in Quantum Field Theory: 1. Why are we philosophers interested in quantum field theory 2. Quantum field theory and the philosopher Part II. Three Approaches to the Foundations of Quantum Field Theory: 3. The usefulness of a general theory of quantized fields 4. Effective field theory in condensed matter physics 5. The triumph and limitations of quantum field theory 6. Comments Discussions Part III. Does Quantum Field Theory Need a Foundation: 7. Does quantum field theory need a foundation? Part IV. Mathematics, Statistical Mechanics and Quantum Field Theory: 8. Renormalization group theory: its basis and formulation in statistical physics 9. Where does quantum field theory fit into the big picture? 10. The unreasonable effectiveness of quantum field theory 11. Comment: the quantum field theory of physics and of mathematics Part V. Quantum Field Theory and Spacetime: Introduction 12. Quantum field theory and spacetime: formalism and reality 13. Quantum field theory of geometry 14. 'Localization' in quantum field theory: how much of QFT is compatible with what we know about spacetime 15. Comments VI. 16. What is quantum field theory and what did we think it was? 17. Comments Discussions Part VII.Renormalization Group: 18. What is fundamental physics? A renormalization group perspective 19. Renormalization group: an interesting yet puzzling idea Part VIII. Non-Abelian Gauge Theory: 20. Gauge fields, gravity and Bohm's theory 21. Is the Aharonov-Bohm effect local? Discussions Part IX. The Ontology of Particles or Fields: 22. The ineliminable classical face of quantum field theory 23. The logic of quanta 24. Do Feynman diagrams endorse a particle ontology? 25. On the ontology of QFT Part X. Panel Discussion.Introduction: Conceptual issues in quantum field theory Part I. Philosophers' Interests in Quantum Field Theory: 1. Why are we philosophers interested in quantum field theory 2. Quantum field theory and the philosopher Part II. Three Approaches to the Foundations of Quantum Field Theory: 3. The usefulness of a general theory of quantized fields 4. Effective field theory in condensed matter physics 5. The triumph and limitations of quantum field theory 6. Comments Discussions Part III. Does Quantum Field Theory Need a Foundation: 7. Does quantum field theory need a foundation? Part IV. Mathematics, Statistical Mechanics and Quantum Field Theory: 8. Renormalization group theory: its basis and formulation in statistical physics 9. Where does quantum field theory fit into the big picture? 10. The unreasonable effectiveness of quantum field theory 11. Comment: the quantum field theory of physics and of mathematics Part V. Quantum Field Theory and Spacetime: Introduction 12. Quantum field theory and spacetime: formalism and reality 13. Quantum field theory of geometry 14. 'Localization' in quantum field theory: how much of QFT is compatible with what we know about spacetime 15. Comments VI. 16. What is quantum field theory and what did we think it was? 17. Comments Discussions Part VII.Renormalization Group: 18. What is fundamental physics? A renormalization group perspective 19. Renormalization group: an interesting yet puzzling idea Part VIII. Non-Abelian Gauge Theory: 20. Gauge fields, gravity and Bohm's theory 21. Is the Aharonov-Bohm effect local? Discussions Part IX. The Ontology of Particles or Fields: 22. The ineliminable classical face of quantum field theory 23. The logic of quanta 24. Do Feynman diagrams endorse a particle ontology? 25. On the ontology of QFT Part X. Panel Discussion.

Mar 1, 200425 citations

A new interpretation of the quantum theory of light

Alan V. Durrant

An approach to the quantum theory of light is described using absorber theory and source field theory. It is assumed that all optical fields have atomic sources, and that the so-called free field is a source field of the surrounding absorbing material of the universe. The field operators are defined to be functions of the atomic operators and act on the states of the atomic sources. The source field of a completely enclosing perfect absorber is found to be mathematically equivalent to the quantised free field of conventional theory, but the physical basis of the theory is different.An approach to the quantum theory of light is described using absorber theory and source field theory. It is assumed that all optical fields have atomic sources, and that the so-called free field is a source field of the surrounding absorbing material of the universe. The field operators are defined to be functions of the atomic operators and act on the states of the atomic sources. The source field of a completely enclosing perfect absorber is found to be mathematically equivalent to the quantised free field of conventional theory, but the physical basis of the theory is different.

European Journal of PhysicsApr 1, 19806 citations

Eective Field Theory

Ben M. Gripaios

Jan 1, 20153 citations

Unitarity and universality in nonrelativistic conformal field theory

Sridip Pal

We relate the notion of unitarity of a ( $0+1$ )-D conformally ( $SL(2,\mathbf{R})$ ) invariant field theory with that of a nonrelativistic conformal (Schr\"odinger) field theory using the fact that $SL(2,\mathbf{R})$ is a subgroup of nonrelativistic conformal (Schr\"odinger) group. Exploiting $SL(2,\mathbf{R})$ unitarity, we derive the unitarity bounds and null conditions for a Schr\"odinger field theory (for the neutral as well as the charged sector). In noninteger dimensions the theory is shown to be nonunitary. The use of the $SL(2,\mathbf{R})$ subgroup opens up the possibility of borrowing results from ( $0+1$ )-D $SL(2,\mathbf{R})$ invariant field theory to explore Schr\"odinger field theory, in particular, the neutral sector, which has otherwise been unexplored.We relate the notion of unitarity of a ($0+1$)-D conformally ($SL(2,\mathbf{R})$) invariant field theory with that of a nonrelativistic conformal (Schr\"odinger) field theory using the fact that $SL(2,\mathbf{R})$ is a subgroup of nonrelativistic conformal (Schr\"odinger) group. Exploiting $SL(2,\mathbf{R})$ unitarity, we derive the unitarity bounds and null conditions for a Schr\"odinger field theory (for the neutral as well as the charged sector). In noninteger dimensions the theory is shown to be nonunitary. The use of the $SL(2,\mathbf{R})$ subgroup opens up the possibility of borrowing results from ($0+1$)-D $SL(2,\mathbf{R})$ invariant field theory to explore Schr\"odinger field theory, in particular, the neutral sector, which has otherwise been unexplored.

arXiv:1802.02262Physical review. D/Physical review. D.May 31, 201811 citations

Field-Theoretical Methods

Robert Alicki

Lecture notes in physicsJan 1, 201012 citations

We relate the notion of unitarity of a (

0+1

)-D conformally (

SL(2,\mathbf{R})

) invariant field theory with that of a nonrelativistic conformal (Schr\"odinger) field theory using the fact that

SL(2,\mathbf{R})

is a subgroup of nonrelativistic conformal (Schr\"odinger) group. Exploiting

SL(2,\mathbf{R})

unitarity, we derive the unitarity bounds and null conditions for a Schr\"odinger field theory (for the neutral as well as the charged sector). In noninteger dimensions the theory is shown to be nonunitary. The use of the

SL(2,\mathbf{R})

subgroup opens up the possibility of borrowing results from (

0+1

)-D

SL(2,\mathbf{R})

invariant field theory to explore Schr\"odinger field theory, in particular, the neutral sector, which has otherwise been unexplored.