151 citations · 1.4k across the 45 of their papers we have counts for
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Ghosts versus Unstable Particles in Quantum Field Theory
Luca Buoninfante
We elucidate the physical nature of ghosts above the multi-particle threshold by contrasting them with unstable particles in quantum field theory. We first consider the asymptotic…
Asymptotic Quantum Dynamics of Ghost Fields
Luca Buoninfante
The dressed propagator of a ghost coupled to ordinary fields develops a pair of complex conjugate poles in the first Riemann sheet above the multi-particle threshold. We study the…
Strict renormalizability as a paradigm for fundamental physics
Luca Buoninfante
An important theoretical achievement of the last century was the realization that strict renormalizability can be a powerful criterion to select Lagrangians in the framework of per…
Remarks on ghost resonances
Luca Buoninfante
In this paper we study various aspects of ghost resonances: the resummation that leads to the dressed propagator, the poles locations, the analytic continuation into the second Rie…
Visions in Quantum Gravity
Luca Buoninfante, Benjamin Knorr, K. Sravan Kumar +36
To deepen our understanding of Quantum Gravity and its connections with black holes and cosmology, building a common language and exchanging ideas across different approaches is cr…
Lectures in Quantum Gravity
Ivano Basile, Luca Buoninfante, Francesco Di Filippo +3
Formulating a quantum theory of gravity lies at the heart of fundamental theoretical physics. This collection of lecture notes encompasses a selection of topics that were covered i…
Non-local positivity bounds: islands in Terra Incognita
Luca Buoninfante, Long-Qi Shao, Anna Tokareva
The requirements of unitarity and causality lead to significant constraints on the Wilson coefficients of an EFT expansion, known as positivity bounds. Their standard derivation re…
Massless and Partially Massless Limits in Quadratic Gravity
Luca Buoninfante
In the context of perturbative quantum field theory, the addition of quadratic-curvature invariants to the Einstein-Hilbert action makes it possible to achieve strict renormalizabi…
New lower bounds on scattering amplitudes: non-locality constraints
Luca Buoninfante, Junsei Tokuda, Masahide Yamaguchi
Under reasonable working assumptions including the polynomial boundedness, one proves the well-known Cerulus-Martin lower bound on how fast an elastic scattering amplitude can decr…
On the contour prescriptions in string-inspired nonlocal field theories
Luca Buoninfante
In quantum field theory, a consistent prescription to define and deform integration contours in the complex energy plane is needed to evaluate loop integrals and compute scattering…
Topological defects in nonlocal field theories
Luca Buoninfante, Yuichi Miyashita, Masahide Yamaguchi
In this paper, we study for the first time topological defects in the context of nonlocal field theories in which Lagrangians contain infinite-order differential operators. In part…
On the assumptions leading to the information loss paradox
Luca Buoninfante, Francesco Di Filippo, Shinji Mukohyama
The information loss paradox is usually stated as an incompatibility between general relativity and quantum mechanics. However, the assumptions leading to the problem are often ove…
Maximal Acceleration, Reciprocity & Nonlocality
Luca Buoninfante
The existence of a fundamental scale is expected to be a key feature of quantum gravity. Many approaches take this property as a starting assumption. Here, instead, we take a less…
Bekenstein bound and uncertainty relations
Luca Buoninfante, Giuseppe Gaetano Luciano, Luciano Petruzziello +1
The non zero value of Planck constant underlies the emergence of several inequalities that must be satisfied in the quantum realm, the most prominent one being Heisenberg Uncer…
Generalized ghost-free propagators in nonlocal field theories
Luca Buoninfante, Gaetano Lambiase, Yuichi Miyashita +2
In this paper we present an iterative method to generate an infinite class of new nonlocal field theories whose propagators are ghost-free. We first examine the scalar field case a…
Nonlocal gravity with worldline inversion symmetry
Steven Abel, Luca Buoninfante, Anupam Mazumdar
We construct a quadratic curvature theory of gravity whose graviton propagator around the Minkowski background respects wordline inversion symmetry, the particle approximation to m…
Transmutation of nonlocal scale in infinite derivative field theories
Luca Buoninfante, Anish Ghoshal, Gaetano Lambiase +1
In this paper we will show an ultraviolet -infrared connection for ghost-free infinite derivative field theories where the Lagrangians are made up of exponentials of entire functio…
Nonlocal generalization of Galilean theories and gravity
Luca Buoninfante, Gaetano Lambiase, Masahide Yamaguchi
In this paper we propose a wider class of symmetries including the Galilean shift symmetry as a subclass. We will show how to construct ghost-free nonlocal actions, consisting of i…
Ghost-free infinite derivative quantum field theory
Luca Buoninfante, Gaetano Lambiase, Anupam Mazumdar
In this paper we will study Lorentz-invariant, infinite derivative quantum field theories, where infinite derivatives give rise to non-local interactions at the energy scale ,…