[PDF] Top 20 The Philosophy of Quantum Field Theory

... all field theories, rather than anything specific to ...“formal field theories”—polynomial functions of field variables, which may be naturally interpreted as equations of motion or Lagrangian or ... See full document

... new philosophy that now addresses cutting‐edge topics like string theory, gauge theories and quantum field theory, it’s important to get back to basics once in a while‐‐to remind ... See full document

... transport theory was developed which is capable of describing electron-phonon dynamics in the semi-classical transition regime of sub-micron semiconductor devices between the currently manufactured devices ... See full document

... As for the mathematical concepts concerning this sort of algebraic method, see [KK19] and the references therein. In [Kik13], the secular equation, derived from the first-principles molecular orbital theory, is ... See full document

... To understand what is needed, it is simplest to first consider classical field theo- ries. A classical algebra of observables is a commutative algebra of functionals on the space of solutions. We need to choose a ... See full document

... appearing Quantum Theory has put radical questions which have challenged not only Clas- sical Physics, but the structure itself of the “explanation” concept born within the “continuous”, “dy- namical” and ... See full document

... as that used for constructing an A-type sigma-model, we might call this TQFT an A-type 2d gauge theory. As far as we know, its boundary conditions have not been analyzed in the literature previously. It is shown ... See full document

... in quantum field theory, which allows them to be written directly in terms of expectation values of nested commutators and anti-commutators of field operators, rather than squared matrix ... See full document

... Note that the above Newtonian equation has a different shape from the standard Newtonian gravity equation, which is usually taught in high-schools. However, although the standard Newtonian gravity equation is applied in ... See full document

... loop quantum gravity (LQG), a background-independent framework aiming to quantize the gravitational degrees of freedom in a nonperturba- tive way [2, ...a quantum theory inclusive of topology change ... See full document

... contemporary quantum field theory, a ghost field, or gauge ghost is an unphysical state in a gauge ...in quantum electrodynamics, in order to maintain manif- est Lorentz invariance, one ... See full document

... gebraic Quantum Field Theory: Its Status and its Future”, where we received useful feedback and suggestions on this work from the organizers and ... See full document

... First, I would like to thank my advisors, Sean Carroll and Mark Wise. Without their support, this thesis would not have been written. Despite entering Caltech with weaker technical skills than many of my fellow graduate ... See full document

... that quantum-field effects in these ultra- cold many-body systems were studied in greater ...field theory, which neglects all quantum field correlations, and describes the condensate with an essentially ... See full document

... in quantum field theory and also Didier ...String Theory and Quantum Field Theory” for the invitation to Hamburg, where part of this work has been ... See full document

... which theory F is a subtheory of G: a class of theories T is said to have the SPASs property if and only if whenever F, G are locally covariant theories in T and η : F →G ˙ is a partial natural isomorphism ... See full document

... [11,12]. Quantum entanglement encodes correlations between degrees of freedom ...separates quantum correlations from the particularities of ...of quantum phase transitions, such as the (effective) ... See full document

... Quantum variables are not equivalent to classical stochastic variables. They can be related by the appearance of measurement-induced fluctuations, which require entropy generation, decoherence, and branching of ... See full document

... The first corresponds to the source atom being in an excited state (labelled by p) and the detector atom being in its ground state (labelled by g ), whilst the second corresponds to both the source and detector atoms ... See full document

... classical field in terms of what can be interpreted as parti- cle annihilation and creation operators (resulting from an appropriate Fourier ...such quantum superpositions is precisely the aim of defining a ... See full document