Violating the Quantum Focusing Conjecture and Quantum Covariant Entropy Bound in d≥5d\ge 5 dimensions

We study the Quantum Focussing Conjecture (QFC) in curved spacetime. Noting that quantum corrections from integrating out massive fields generally induce a Gauss-Bonnet term, we study Einstein-Hilbert-Gauss-Bonnet gravity and show for $d\ge 5$ spacetime dimensions that weakly-curved solutions can violate the associated QFC for either sign of the Gauss-Bonnet coupling. The nature of the violation shows that -- so long as the Gauss-Bonnet coupling is non-zero -- it will continue to arise for local effective actions containing arbitrary further higher curvature terms, and when gravity is coupled to generic $d\ge 5$ theories of massive quantum fields. The argument also implies violations of a recently-conjectured form of the generalized covariant entropy bound. The possible validity of the QFC and covariant entropy bound in $d\le 4$ spacetime dimensions remains open.Comment: 13 pages, no figure; v2: note adde

The Quantum Null Energy Condition in Curved Space

The quantum null energy condition (QNEC) is a conjectured bound on components $(T_{kk} = T_{ab} k^a k^b$) of the stress tensor along a null vector $k^a$ at a point $p$ in terms of a second $k$-derivative of the von Neumann entropy $S$ on one side of a null congruence $N$ through $p$ generated by $k^a$. The conjecture has been established for super-renormalizeable field theories at points $p$ that lie on a bifurcate Killing horizon with null tangent $k^a$ and for large-N holographic theories on flat space. While the Koeller-Leichenauer holographic argument clearly yields an inequality for general $(p,k^a)$, more conditions are generally required for this inequality to be a useful QNEC. For $d\le 3$, for arbitrary backgroud metric satisfying the null convergence condition $R_{ab} k^a k^b \ge 0$, we show that the QNEC is naturally finite and independent of renormalization scheme when the expansion $\theta$ and shear $\sigma_{ab}$ of $N$ at point $p$ satisfy $\theta |_p= \dot{\theta}|_p =0$, $\sigma_{ab}|_p=0$. This is consistent with the original QNEC conjecture. But for $d=4,5$ more conditions are required. In particular, we also require the vanishing of additional derivatives and a dominant energy condition. In the above cases the holographic argument does indeed yield a finite QNEC, though for $d\ge6$ we argue these properties to fail even for weakly isolated horizons (where all derivatives of $\theta, \sigma_{ab}$ vanish) that also satisfy a dominant energy condition. On the positive side, a corrollary to our work is that, when coupled to Einstein-Hilbert gravity, $d \le 3$ holographic theories at large $N$ satisfy the generalized second law (GSL) of thermodynamics at leading order in Newton's constant $G$. This is the first GSL proof which does not require the quantum fields to be perturbations to a Killing horizon.Comment: 31 pages, no figure; v2: signs corrected and new comments for d=3; v3: minor corrections; v4: minor modifications to address referee comments; v5: paragraph containing equation (2.13) modifie

Testing Sustainability of German Fiscal Policy. Evidence for the Period 1960 – 2003

In this paper we test whether German public debt has been sustainable by resorting to a test proposed by Bohn (1998). We apply non-parametric and semi-parametric regressions with time depending coefficients. This test shows that the mean of the coefficient relevant for sustainability has been significantly positive over the time period considered. However, there is a negative trend in that coefficient which seems to have ceased to decline only in the middle to late 1990s. Further, we find evidence that the response of the primary deficit is a U-shaped function of the debt ratio which first declines and then rises after a certain threshold of the debt ratio is exceeded.public debt, intertemporal budget constraint, varying coefficient model, non-parametric estimation

A Look Into the Stand with Survivors Protest

The Texas Orato

A Look at the Authority of the Parish Pastor

Changes in society, misuse and abuse of authority in the pastoral office and changes in congregations concerning the role of the pastor, have all led to a need for defining and identifying what authority in the church is, and what authority the pastor has. The scope of this project was to look at the Scriptural and Confessional foundations of Pastoral Authority along with discussions with the Board of Elders, Constitution Committee and Bible Study groups, to draw a basis for: 1) a definition of “Pastoral Authority ; and 2) the right use of that authority in the office of the parish pastor

Who Do You Think You Are? And Who Would You Like to Become?

Ultimately -y goal would be to enhance staff satisfaction to the point of better retention of nursing assistants on my floor. I thought this would also assist in improving RN satisfaction, as there would be solid, reliable assistive staff on the floor. Research of the literature shows staff retention has a direct impact on patient satisfaction as well. The constant cycle of replacing staff is costly to the organization and diminishes satisfaction to all staff as they become trapped in the endless cycle of training new staff in. Patient quality of care suffers, as newly trained staff needs time to develop their skill at caring for patients with mental illness and dementias

Mirage: A New Package for the Simulation of Gravitationally Microlensed Quasars

We present Mirage, a new package for simulating gravitationally lensed quasars that allows simulation of arbitrarily sized emitting regions of the quasar’s accretion disk. We develop a robust, large-scale simulator, wirtten in Python, to model gravitationally lensed quasars. Numerical simulation of gravitationally microlensed quasars provides a tool to determine the physical size and temperature profile of quasars accretion disks which is impossible through direct observation. The method consists of ray-tracing approximately 1010 paths through a simulated starfield, taking advantage of the latest technologies in cluster computing,to calculate flux received by the observer from each lensed image from different regions of the accretion disk as the quasar moves relative to the lensing galaxy. We compare our simulations to observations of QSO2237+0305 in optical and X-ray wavebands to place constraints on the relative size of the x-ray and optical emitting regions of the quasar’s accretion disk