Toward a Logic of the Organism: A Process Philosophical Consideration

Mathematical models applied in contemporary theoretical and systems biology are based on some implicit ontological assumptions about the nature of organisms. This article aims to show that real organisms reveal a logic of internal causality transcending the tacit logic of biological modeling. Systems biology has focused on models consisting of static systems of differential equations operating with fixed control parameters that are measured or fitted to experimental data. However, the structure of real organisms is a highly dynamic process, the internal causality of which can only be captured by continuously changing systems of equations. In addition, in real physiological settings kinetic parameters can vary by orders of magnitude, i.e., organisms vary the value of internal quantities that in models are represented by fixed control parameters. Both the plasticity of organisms and the state dependence of kinetic parameters adds indeterminacy to the picture and asks for a new statistical perspective. This requirement could be met by the arising Biological Statistical Mechanics project, which promises to do more justice to the nature of real organisms than contemporary modeling. This article concludes that Biological Statistical Mechanics allows for a wider range of organismic ontologies than does the tacitly followed ontology of contemporary theoretical and systems biology, which are implicitly and explicitly based on systems theory.

Non-Linear Employment Effects of Tax Policy

We study the non-linear propagation mechanism of tax policy in a heterogeneous agent equilibrium business cycle model with search frictions in the labor market and an extensive margin of employment adjustment. The model exhibits endogenous job destruction and endogenous hiring standards in the form of occasionally-binding zero-surplus constraints. After parameterizing the model using U.S. data, we find that the dynamic response of employment to a temporary change in the labor income tax is highly non-linear, displaying sizable asymmetries and state-dependence. Notably, the response to a tax rate cut is at least twice as large in a recession as in an expansion.

Instrument policy mix and firm size: is there complementarity between R&D subsidies and R&D tax credits?

Nowadays, a rising number of evaluations investigates a multifaceted concept of the policy mix. Our study specifically focuses on the mix of two most frequently used supply-side instruments–R&D subsidies and R&D tax credits. Drawing on the longitudinal sample of Spanish manufacturing firms, we investigate whether there is a complementary interaction between these policy instruments with respect to product and process innovations. Moreover, by employing a dynamic random-effects probit estimator, we account for the persistence of innovation and endogeneity of public support. The results, that are separately estimated for SMEs and large firms, uniformly show evidence of no interplay between two policy instruments either in SMEs or large firms. However, among factors that influence the propensity to product and process innovations, by far, the largest effect is generated by true state dependence. These findings provide some policy implications for fostering product and process innovations in the long run.

Equation-of-state Dependence of Gravitational Waves in Core-collapse Supernovae

Gravitational waves (GWs) provide unobscured insight into the birthplace of neutron stars and black holes in core-collapse supernovae (CCSNe). The nuclear equation of state (EOS) describing these dense environments is yet uncertain, and variations in its prescription affect the proto−neutron star (PNS) and the post-bounce dynamics in CCSN simulations, subsequently impacting the GW emission. We perform axisymmetric simulations of CCSNe with Skyrme-type EOSs to study how the GW signal and PNS convection zone are impacted by two experimentally accessible EOS parameters, (1) the effective mass of nucleons, m ⋆, which is crucial in setting the thermal dependence of the EOS, and (2) the isoscalar incompressibility modulus, K sat. While K sat shows little impact, the peak frequency of the GWs has a strong effective mass dependence due to faster contraction of the PNS for higher values of m ⋆ owing to a decreased thermal pressure. These more compact PNSs also exhibit more neutrino heating, which drives earlier explosions and correlates with the GW amplitude via accretion plumes striking the PNS, exciting the oscillations. We investigate the spatial origin of the GWs and show the agreement between a frequency-radial distribution of the GW emission and a perturbation analysis. We do not rule out overshoot from below via PNS convection as another moderately strong excitation mechanism in our simulations. We also study the combined effect of effective mass and rotation. In all our simulations we find evidence for a power gap near ∼1250 Hz; we investigate its origin and report its EOS dependence.

Finding pythons in unexpected places

We argue that novel (highly nonclassical) quantum extremal surfaces play a crucial role in reconstructing the black hole interior even for isolated, single-sided, non-evaporating black holes (i.e. with no auxiliary reservoir). Specifically, any code subspace where interior outgoing modes can be excited will have a quantum extremal surface in its maximally mixed state. We argue that as a result, reconstruction of interior outgoing modes is always exponentially complex. Our construction provides evidence in favor of a strong Python’s lunch proposal: that nonminimal quantum extremal surfaces are the exclusive source of exponential complexity in the holographic dictionary. We also comment on the relevance of these quantum extremal surfaces to the geometrization of state dependence in the typicality arguments for firewalls.

The Relationship between Consumption and CO2 Emissions: Evidence for Portugal

This paper establishes an empirical relationship between CO2 emissions from burning fossil fuels and household consumption of nondurable goods and services. Using a typical life cycle-permanent income hypothesis framework, we reject the hypothesis that inclusion of CO2 emissions in the consumption function is not supported by the data. Furthermore, our results suggest the existence of a distaste effect or negative state dependence effect. This result has important policy implications as it suggests that decarbonizing the economy would ultimately stimulate household consumption. Our results also have implications for both the cyclical behavior and the smoothing process of consumption, which depend on the branch of the environmental Kuznets curve that the country is on as well as on the prevalence of intertemporal dependent preferences.