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Related papers: A More Sensitive Lorentzian State Sum

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This paper deals with several technical issues of non-perturbative four-dimensional Lorentzian canonical quantum gravity in the continuum that arose in connection with the recently constructed Wheeler-DeWitt quantum constraint operator. 1)…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Thomas Thiemann

We introduce an integrable Hamiltonian system which Lax deforms the Dirac operator D=d+d* on a finite simple graph or compact Riemannian manifold. We show that the nonlinear isospectral deformation always leads to an expansion of the…

Dynamical Systems · Mathematics 2013-06-04 Oliver Knill

We generalize a model recently proposed for Euclidean quantum gravity to the case of Lorentzian signature. The main features of the Euclidean model are preserved in the Lorentzian one. In particular, the boundary Hilbert space matches the…

General Relativity and Quantum Cosmology · Physics 2009-12-08 Roberto Pereira

Lorentzian simplicial quantum gravity is a non-perturbatively defined theory of quantum gravity which predicts a positive cosmological constant. Since the approach is based on a sum over space-time histories, it is perturbatively…

High Energy Physics - Theory · Physics 2009-11-10 J. Ambjorn , J. Jurkiewicz , R. Loll

We propose an experimental design for universal continuous-variable quantum computation that incorporates recent innovations in linear-optics-based continuous-variable cluster state generation and cubic-phase gate teleportation. The first…

Quantum Physics · Physics 2018-03-16 Rafael N. Alexander , Shota Yokoyama , Akira Furusawa , Nicolas C. Menicucci

Any method for estimating the ensemble average of arbitrary operator (observables or not, including the density matrix) relates the quantity of interest to a complete set of observables, i.e. a quorum}. This corresponds to an expansion on…

Quantum Physics · Physics 2009-11-06 G. Mauro D'Ariano , Lorenzo Maccone , Matteo G. A. Paris

To understand better the quantum structure of field theory and standard model in particle physics, it is necessary to investigate carefully the divergence structure in quantum field theories (QFTs) and work out a consistent framework to…

High Energy Physics - Theory · Physics 2015-06-18 Yue-Liang Wu

We present a spinfoam formulation of Lorentzian quantum General Relativity. The theory is based on a simple generalization of an Euclidean model defined in terms of a field theory over a group. The model is an extension of a recently…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Alejandro Perez , Carlo Rovelli

Models for deterministic quantum mechanics of Cartan-Randers type are introduced, together with the fundamental notions of the concentration of measure theory. We explain how the application of the concentration of measure to Cartan-Randers…

Quantum Physics · Physics 2020-03-10 Ricardo Gallego Torromé

We show that there is a sector of quantum general relativity which may be expressed in a completely holographic formulation in terms of states and operators defined on a finite boundary. The space of boundary states is built out of the…

High Energy Physics - Theory · Physics 2009-10-31 Lee Smolin

Particle localization within quantum field theory is revisited. Canonical quantization of a free scalar field theory is performed in a manifestly Lorentz covariant way with respect to an arbitrary 3-surface $\Sigma$, which is the…

High Energy Physics - Theory · Physics 2018-08-01 Matej Pavšič

We review some of the geometry of the quantum projective plane with emphasis on the construction of a differential calculus and of the Dirac operator (of a spin^c-structure). We also report on anti-self-dual connections on line bundles, the…

Quantum Algebra · Mathematics 2010-05-18 Francesco D'Andrea , Giovanni Landi

One can try to define the theory of quantum gravity as the sum over geometries. In two dimensions the sum over {\it Euclidean} geometries can be performed constructively by the method of {\it dynamical triangulations}. One can define a {\it…

General Relativity and Quantum Cosmology · Physics 2017-08-23 J. Ambjorn

A simple yet efficient method of linear regression estimation (LRE) is presented for quantum state tomography. In this method, quantum state reconstruction is converted into a parameter estimation problem of a linear regression model and…

Quantum Physics · Physics 2013-12-18 Bo Qi , Zhibo Hou , Li Li , Daoyi Dong , Guoyong Xiang , Guangcan Guo

Over the last two years, the canonical approach to quantum gravity based on connections and triads has been put on a firm mathematical footing through the development and application of a new functional calculus on the space of gauge…

High Energy Physics - Theory · Physics 2015-06-26 Abhay Ashtekar

We present a rigorous quantization scheme that yields a quantum field theory in general boundary form starting from a linear field theory. Following a geometric quantization approach in the K\"ahler case, state spaces arise as spaces of…

High Energy Physics - Theory · Physics 2012-08-10 Robert Oeckl

Recent progress in quantum field theory and quantum gravity relies on mixed boundary conditions involving both normal and tangential derivatives of the quantized field. In particular, the occurrence of tangential derivatives in the boundary…

High Energy Physics - Theory · Physics 2007-05-23 Giampiero Esposito

We review some recent attempts to extract information about the nature of quantum gravity, with and without matter, by quantum field theoretical methods. More specifically, we work within a covariant lattice approach where the individual…

High Energy Physics - Theory · Physics 2007-05-23 J. Ambjorn , J. Jurkiewicz , R. Loll

Relativistic invariant projectors of states in a complex bispinor space on a complex spinor space are constructed. An expression for sections of bundle with connection on group SU(4) in an explicit form has been obtained. Within the…

Quantum Physics · Physics 2007-05-23 H. V. Grushevskaya

We analyze the heavy quark bound state spectrum using an order-dependent conformal mapping to re-sum the perturbative expansion for current correlators. The procedure consists of two main steps. Firstly, the Borel plane structure of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. F. Jones , A. Ritz , I. L. Solovtsov