Forgiveness and Reconciliation

Forgiveness and reconciliation are central to moral life; after all, everyone will be wronged by others and will then face the dual decisions of whether to forgive and whether to reconcile. It is therefore important that we have a clear analysis of each, as well as a thoroughly articulated understanding of how they relate to and differ from each other. Forgiveness has received considerably more attention in the Western philosophical literature than has reconciliation. In this paper I aim to give it the attention it deserves and develop an account of interpersonal reconciliation. On my view reconciliation is fundamentally bilateral (whereas forgiveness is fundamentally unilateral). It entails transparency and agreement between the wrongdoer and the victim as to the nature of a past wrong or set of wrongs. And, it requires that moral repair be made between the two parties (which entails that both parties bear proper attitudes towards each other). In making my case I contrast reconciliation with toleration and collaboration, in order to demonstrate that reconciliation also entails forgiveness (though forgiveness does not entail reconciliation)

The Limits of the Rights to Free Thought and Expression

It is often held that people have a moral right to believe and say whatever they want. For instance, one might claim that they have a right to believe racist things as long as they keep those thoughts to themselves. Or, one might claim that they have a right to pursue any philosophical question they want as long as they do so with a civil tone. In this paper I object to those claims and argue that no one has such unlimited moral rights. In Part 1 I explore the value of the freedoms of thought and expression. In Part 2 I argue against the unlimited moral right to free expression, focusing in particular on the special obligations and moral constraints that obtain for academics. In Part 3 I argue against the unlimited moral right to free thought

The Violence of Silencing

I argue that silencing (the act of preventing someone from communicating, broadly construed) can be an act of both interpersonal and institutional violence. My argument has two main steps. First, I follow others in analyzing violence as violation of integrity and show that undermining someone’s capacities as a knower can be such a violation. Second, I argue that silencing someone can violate their epistemic capacities in that way. I conclude by exploring when silencing someone might be morally justifiable, even if doing so is an act of violence

Design of a 60 GHz beam waveguide antenna positioner

A development model antenna positioner mechanism with an integral 60 GHz radio frequency beam waveguide is discussed. The system features a 2-ft diameter carbon-fiber reinforced epoxy antenna reflector and support structure, and a 2-degree-of-freedom elevation over azimuth mechanism providing hemispherical field of view. Emphasis is placed on the constraints imposed on the mechanism by the radio frequency subsystems and how they impacted the mechanical configuration

Data-Space Inversion with Ensemble Smoother

Reservoir engineers use large-scale numerical models to predict the production performance in oil and gas fields. However, these models are constructed based on scarce and often inaccurate data, making their predictions highly uncertain. On the other hand, measurements of pressure and flow rates are constantly collected during the operation of the field. The assimilation of these data into the reservoir models (history matching) helps to mitigate uncertainty and improve their predictive capacity. History matching is a nonlinear inverse problem, which is typically handled using optimization and Monte Carlo methods. In practice, however, generating a set of properly history-matched models that preserve the geological realism is very challenging, especially in cases with complicated prior description, such as models with fractures and complex facies distributions. Recently, a new data-space inversion (DSI) approach was introduced in the literature as an alternative to the model-space inversion used in history matching. The essential idea is to update directly the predictions from a prior ensemble of models to account for the observed production history without updating the corresponding models. The present paper introduces a DSI implementation based on the use of an iterative ensemble smoother and demonstrates with examples that the new implementation is computationally faster and more robust than the earlier method based on principal component analysis. The new DSI is also applied to estimate the production forecast in a real field with long production history and a large number of wells. For this field problem, the new DSI obtained forecasts comparable with a more traditional ensemble-based history matching.Comment: 33 pages, 14 figure

Gas Loss by Ram Pressure Stripping and Internal Feedback From Low Mass Milky Way Satellites

The evolution of dwarf satellites of the Milky Way is affected by the combination of ram pressure and tidal stripping, and internal feedback from massive stars. We investigate gas loss processes in the smallest satellites of the Milky Way using three-dimensional, high resolution, idealized wind tunnel simulations, accounting for gas loss through both ram pressure stripping and expulsion by supernova feedback. Using initial conditions appropriate for a dwarf galaxy like Leo T, we investigate whether or not environmental gas stripping and internal feedback can quench these low mass galaxies on the expected timescales, shorter than 2 Gyr. We find that supernova feedback contributes negligibly to the stripping rate for these low star formation rate galaxies. However, we also find that ram pressure stripping is less efficient than expected in the stripping scenarios we consider. Our work suggests that, although ram pressure stripping can eventually completely strip these galaxies, other physics is likely at play to reconcile our computed stripping times with the rapid quenching timescales deduced from observations of low mass Milky Way dwarf galaxies. We discuss the roles additional physics may play in this scenario, including host-satellite tidal interactions, cored vs. cuspy dark matter profiles, reionization, and satellite pre-processing. We conclude that a proper accounting of these physics together is necessary to understand the quenching of low mass Milky Way satellites.Comment: 16 pages, 7 figures. Accepted for publication in Ap

Simulating Metal Mixing of Both Common and Rare Enrichment Sources in a Low-mass Dwarf Galaxy

One-zone models constructed to match observed stellar abundance patterns have been used extensively to constrain the sites of nucleosynthesis with sophisticated libraries of stellar evolution and stellar yields. The metal mixing included in these models is usually highly simplified, although it is likely to be a significant driver of abundance evolution. In this work we use high-resolution hydrodynamics simulations to investigate how metals from individual enrichment events with varying source energies E_(ej) mix throughout the multiphase interstellar medium (ISM) of a low-mass (M_(gas) = 2 × 10⁶ M_⊙), low-metallicity, isolated dwarf galaxy. These events correspond to the characteristic energies of both common and exotic astrophysical sites of nucleosynthesis, including asymptotic giant branch winds (E_(ej) ~ 10⁴⁶ erg), neutron star–neutron star mergers (E_(ej) ~ 10⁴⁹ erg), supernovae (E_(ej) ~ 10⁵¹ erg), and hypernovae (E_(ej) ~ 10⁵² erg). We find the mixing timescales for individual enrichment sources in our dwarf galaxy to be long (100 Myr–1 Gyr), with a clear trend of increasing homogeneity for the more energetic events. Given these timescales, we conclude that the spatial distribution and frequency of events are important drivers of abundance homogeneity on large scales; rare, low-E_(ej) events should be characterized by particularly broad abundance distributions. The source energy E_(ej) also correlates with the fraction of metals ejected in galactic winds, ranging anywhere from 60% at the lowest energy to 95% for hypernovae. We conclude by examining how the radial position, local ISM density, and global star formation rate influence these results