Phenomenological Actualism. A Husserlian Metaphysics of Modality?

Considering the importance of possible-world semantics for modal logic and for current debates in the philosophy of modality, a phenomenologist may want to ask whether it makes sense to speak of “possible worlds” in phenomenology. The answer will depend on how "possible worlds" are to be interpreted. As that latter question is the subject of the debate about possibilism and actualism in contemporary modal metaphysics, my aim in this paper is to get a better grip on the former question by exploring a Husserlian stance towards this debate. I will argue that the phenomenologist’s way to deal with the problem of intentional reference to mere possibilia is analogous to the actualist’s idea of how “possible worlds” are to be interpreted. Nevertheless, I will be pointing to a decisive difference in the metaphilosophical preconditions of what I call "phenomenological actualism" and analytical versions of actualism

The ground of ground, essence, and explanation

This paper is about the so-called meta-grounding question, i.e. the question of what grounds grounding facts of the sort ‘φ is grounded in Γ ’. An answer to this question is pressing since some plausible assumptions about grounding and fundamentality entail that grounding facts must be grounded. There are three different accounts on the market which each answer the meta-grounding question differently: Bennett’s and deRosset’s “Straight Forward Account” (SFA), Litland’s “Zero-Grounding Account” (ZGA), and “Grounding Essentialism” (GE). I argue that if grounding is to be regarded as metaphysical explanation (i.e. if unionism is true), (GE) is to be preferred over (ZGA) and (SFA) as only (GE) is compatible with a crucial consequence of the thought that grounding is metaphysical explanation. In this manner the paper contributes not only to discussions about the ground of ground but also to the ongoing debate concerning the relationship between ground, essence, and explanation

Tree Parity Machine Rekeying Architectures

The necessity to secure the communication between hardware components in embedded systems becomes increasingly important with regard to the secrecy of data and particularly its commercial use. We suggest a low-cost (i.e. small logic-area) solution for flexible security levels and short key lifetimes. The basis is an approach for symmetric key exchange using the synchronisation of Tree Parity Machines. Fast successive key generation enables a key exchange within a few milliseconds, given realistic communication channels with a limited bandwidth. For demonstration we evaluate characteristics of a standard-cell ASIC design realisation as IP-core in 0.18-micrometer CMOS-technology

Divisibility of binomial coefficients by powers of two

For nonnegative integers $j$ and $n$ let $\Theta(j,n)$ be the number of entries in the $n$-th row of Pascal's triangle that are not divisible by $2^{j+1}$. In this paper we prove that the family $j\mapsto\Theta(j,n)$ usually follows a normal distribution. The method used for proving this theorem involves the computation of first and second moments of $\Theta(j,n)$, and uses asymptotic analysis of multivariate generating functions by complex analytic methods, building on earlier work by Drmota (1994) and Drmota, Kauers and Spiegelhofer (2016).Comment: 15 page

Definability and stability of multiscale decompositions for manifold-valued data

We discuss multiscale representations of discrete manifold-valued data. As it turns out that we cannot expect general manifold-analogues of biorthogonal wavelets to possess perfect reconstruction, we focus our attention on those constructions which are based on upscaling operators which are either interpolating or midpoint-interpolating. For definable multiscale decompositions we obtain a stability result