Related papers: Light ray fluctuation and lattice refinement of si…
One of the most common expectations of a quantum theory of gravity is that space-time is uncertain or fluctuating at microscopic scales, making it a stochastic medium for particle propagation. Particles traversing this space-time may…
Quantum treatment of physical reference frame leads to the Ricci flow of quantum spacetime, which is a quite rigid framework to quantum and renormalization effect of gravity. The theory has a low characteristic energy scale described by a…
In the framework of the power-counting renormalizable theory of gravitation, recently proposed by Ho\v{r}ava, we study the limit $\lambda\to\infty$, which is arguably the most natural candidate for the ultraviolet fixed point of the…
Using the generalized Langevin equations involving the stress tensor approach, we study the dynamics of a perfectly reflecting mirror which is exposed to the electromagnetic radiation pressure by a laser beam in a fluid at finite…
The evolution of linear cosmological perturbations in modified theories of gravity is investigated assuming the Palatini formalism. It has been discussed about the stability problem in this model based on the equivalence between f(R)…
Starting from an heuristic approach to the semiclassical limit in loop quantum gravity, the construction of effective Hamiltonians describing Planck length corrections to the propagation of photons and spin 1/2 fermions, leading to modified…
We study quantum spacetime fluctuations near light-sheet horizons associated with a Rindler wedge in AdS spacetime, in the context of AdS/CFT. In particular, we solve the vacuum Einstein equation near the light-sheet horizon, augmented with…
In any dimension $D$, the Euclidean Einstein-Hilbert action, which describes gravity in the absence of matter, can be discretized over random discrete spaces obtained by gluing families of polytopes together in all possible ways. In the…
We review the fundamental ideas of quantizing a theory on a Light Front including the Hamiltonian approach to the problem of bound states on the Light Front and the limiting transition from formulating a theory in Lorentzian coordinates…
We consider scattering in quantum gravity and derive long-range classical and quantum contributions to the scattering of light-like bosons and fermions (spin-0, spin-1/2, spin-1) from an external massive scalar field, such as the Sun or a…
We consider a discrete model of euclidean quantum gravity in four dimensions based on a summation over random simplicial manifolds. The action used is the Einstein-Hilbert action plus an $R^2$-term. The phase diagram as a function of the…
Mean-field mixed quantum--classical dynamics could provide a much-needed means to inexpensively model quantum electrodynamical phenomena, by describing the optical field and its vacuum fluctuations classically. However, this approach is…
We introduce a set of four very high resolution cosmological simulations for exploring $f(R)$-gravity, with $2048^3$ particles in $768\,h^{-1}\textrm{Mpc}$ and $1536\,h^{-1}\textrm{Mpc}$ simulation boxes, both for a $|\overline{f_{R0}}| =…
Most of today's lattice simulations are performed in the isospin symmetric limit of the light quark sector. Mass reweighting is a technique to include effects of isospin breaking in the sea quarks at moderate numerical cost. We will give a…
We discuss the density fluctuations of a fluid due to zero point motion. These can be regarded as density fluctuations in the phonon vacuum state. We assume a linear dispersion relation with a fixed speed of sound and calculate the density…
In this contribution, we discuss the asymptotic safety scenario for quantum gravity with a functional renormalisation group approach that disentangles dynamical metric fluctuations from the background metric. We review the state of the art…
It has been shown that at the semi-classical order, gravitational theories with quantum fluctuations can be effectively recast as modified theories of gravity with non-minimal gravity-matter couplings. We proceed from an observational…
We present here the first lattice simulation of symplectic quantization, a new functional approach to quantum field theory which allows to define an algorithm to numerically sample the quantum fluctuations of fields directly in Minkowski…
Quantum light-matter systems at strong coupling are notoriously challenging to analyze due to the need to include states with many excitations in every coupled mode. We propose a nonperturbative approach to analyze light-matter correlations…
The non-equivalence between the metric and Palatini formalisms of $f(R)$ gravity is an intriguing feature of these theories. However, in the recently proposed hybrid metric-Palatini gravity, consisting of the superposition of the metric…