Paradigms, possibilities and probabilities: Comment on Hinterecker et al. (2016)

Hinterecker et al. (2016) compared the adequacy of the probabilistic new paradigm in reasoning with the recent revision of mental models theory (MMT) for explaining a novel class of inferences containing the modal term “possibly”. For example, the door is closed or the window is open or both, therefore, possibly the door is closed and the window is open (A or B or both, therefore, possibly(A & B)). They concluded that their results support MMT. In this comment, it is argued that Hinterecker et al. (2016) have not adequately characterised the theory of probabilistic validity (p-validity) on which the new paradigm depends. It is unclear how p-validity can be applied to these inferences, which are anyway peripheral to the theory. It is also argued that the revision of MMT is not well motivated and its adoption leads to many logical absurdities. Moreover, the comparison is not appropriate because these theories are defined at different levels of computational explanation. In particular, revised MMT lacks a provably consistent computational level theory that could justify treating these inferences as valid. It is further argued that the data could result from the non-colloquial locutions used to express the premises. Finally, an alternative pragmatic account is proposed based on the idea that a conclusion is possible if what someone knows cannot rule it out. This account could be applied to the unrevised mental model theory rendering the revision redundant

Qinghai Province and the Question of Chinese Rural Women’s Land Ownership Rights

Article 30 of the 2005 People’s Republic of China Law on the Protection of Women’s Rights stipulates that women enjoy equal rights to property as men. However, issues of marital status, patriarchal social structure, and minority status complicate the legal mediation of women’s rural property. Qinghai Province’s Hualong Hui Autonomous County (southeast of the provincial capital of Xining) offers one primary example of the difficulty of guaranteeing rural women’s land rights, not only because of the above-mentioned problems and the county’s autonomous status, but also because of the general lack of awareness of land rights and widespread illiteracy. My thesis answers why the number of property right violations in rural Qinghai Province is increasing. I chose this location in China for two reasons. The first reason is the province’s cultural diversity as a crossroads between Han, Hui, Tibetan, and other minority cultures. The second reason is that many of the legal clients of Women’s Watch-China (the location of my previous internship) who have been disputing property rights violations are from this province. I utilize eyewitness accounts from clients and lawyers disputing these cases, as well as statistical analysis from both Chinese and English sources. When analyzing sources concerning autonomous or culturally diverse regions in China, it is important to remember that the rights of officially recognized minorities remain a highly controversial issue, largely because of widespread sentiment that public policy does not represent their interests. As a result, minority status may not be discussed in domestic surveys and accounts on women’s land rights disputes. It is for this reason that I present a clearer picture of the correlation between women’s land rights violations and social, marital, communal, and cultural factors

A detector module with highly efficient surface-alpha event rejection operated in CRESST-II Phase 2

The cryogenic dark matter experiment CRESST-II aims at the direct detection of WIMPs via elastic scattering off nuclei in scintillating CaWO$_4$ crystals. We present a new, highly improved, detector design installed in the current run of CRESST-II Phase 2 with an efficient active rejection of surface-alpha backgrounds. Using CaWO$_4$ sticks instead of metal clamps to hold the target crystal, a detector housing with fully-scintillating inner surface could be realized. The presented detector (TUM40) provides an excellent threshold of ${\sim}\,0.60\,$keV and a resolution of $\sigma\,{\approx}\,0.090$ keV (at 2.60$\,$keV). With significantly reduced background levels, TUM40 sets stringent limits on the spin-independent WIMP-nucleon scattering cross section and probes a new region of parameter space for WIMP masses below 3$\,$GeV/c$^2$. In this paper, we discuss the novel detector design and the surface-alpha event rejection in detail.Comment: 9 pages, 6 figure

Oostende in 1835: Reisebriefe aus Belgien

The victim was part of an advance team which was defining the perimeter of a suspected mined area, with the help of a local guide. The victim was putting in metal markers about 3m away from the existing mined-area boundary stakes. At 09:20 the victim stepped on a mine about 8m away from the existing boundary stakes. He suffered a cracked bone and bruising to his left foot

On the role of deduction in reasoning from uncertain premises

The probabilistic approach to reasoning hypothesizes that most reasoning, both in everyday life and in science, takes place in contexts of uncertainty. The central deductive concepts of classical logic, consistency and validity, can be generalised to cover uncertain degrees of belief. Binary consistency can be generalised to coherence, where the probability judgments for two statements are coherent if and only if they respect the axioms of probability theory. Binary validity can be generalised to probabilistic validity (p-validity), where an inference is p-valid if and only if the uncertainty of its conclusion cannot be coherently greater than the sum of the uncertainties of its premises. But the fact that this generalisation is possible in formal logic does not imply that people will use deduction in a probabilistic way. The role of deduction in reasoning from uncertain premises was investigated across ten experiments and 23 inferences of differing complexity. The results provide evidence that coherence and p-validity are not just abstract formalisms, but that people follow the normative constraints set by them in their reasoning. It made no qualitative difference whether the premises were certain or uncertain, but certainty could be interpreted as the endpoint of a common scale for degrees of belief. The findings are evidence for the descriptive adequacy of coherence and p-validity as computational level principles for reasoning. They have implications for the interpretation of past findings on the roles of deduction and degrees of belief. And they offer a perspective for generating new research hypotheses in the interface between deductive and inductive reasoning. Keywords: Reasoning; deduction; probabilistic approach; coherence; p-validit

Results on MeV-scale dark matter from a gram-scale cryogenic calorimeter operated above ground

Models for light dark matter particles with masses below 1 GeV/c$^2$ are a natural and well-motivated alternative to so-far unobserved weakly interacting massive particles. Gram-scale cryogenic calorimeters provide the required detector performance to detect these particles and extend the direct dark matter search program of CRESST. A prototype 0.5 g sapphire detector developed for the $\nu$-cleus experiment has achieved an energy threshold of $E_{th}=(19.7\pm 0.9)$ eV, which is one order of magnitude lower than previous results and independent of the type of particle interaction. The result presented here is obtained in a setup above ground without significant shielding against ambient and cosmogenic radiation. Although operated in a high-background environment, the detector probes a new range of light-mass dark matter particles previously not accessible by direct searches. We report the first limit on the spin-independent dark matter particle-nucleon cross section for masses between 140 MeV/c$^2$ and 500 MeV/c$^2$.Comment: 6 pages, 6 figures, v3: ancillary files added, v4: high energy spectrum (0.6-12keV) added to ancillary file

Setup of a UHV System for the Production of Tungsten TES

Humanity has concerned itself with the question of the basic elements of nature over thousands of years. The technological evolution of the last hundred years improved our understanding of the particle nature of matter. However, this is only true for particles, that reveal themselves to us by participating at electromagnetic interactions, or, like neutrinos, are closely related to an electromagnetically interacting partner. Large scale gravitation studies concluded, that these known forms of matter only account for about a sixth of the overall gravitationally interacting matte in the universe. Due to its invisibility to electromagnetic particles, the missing mass is referred to as dark matter. While gravitation still remains inaccessible to us on particle scales, technical evolution opened up the field of particle studies based on the weak interaction force, which is a promising field for dark matter studies, since reasonable suspicion exists, that dark matter is also weakly interacting. Low interaction cross sections and small signals are making particle detection via weak interaction challenging and require sophisticated technology. The CRESST experiment (Cryogenic Rare Event Search with Superconducting Thermometers) and SuperCDMS (Super Cryogenic Dark Matter Search) are aiming to directly detect dark matter particles and investigate their properties by taking advantage of TES (transition edge sensors) to measure the small signals. These TES’s are manufactured from thin tungsten films, that are thermally coupled to absorber crystals. To also meet the detection requirements for low interaction rates, a large numbers of detectors, and thus a large numbers of TES are needed. In order to achieve the required sensitivity, tuning the superconductive properties of the tungsten films is essential. The transition temperature defines the sensitivity range of the TES and the slope of the transition edge their sensitivity. In particular the low superconductive transition of about 15 mK in bulk material makes tungsten the favored material in cryogenic particle detection. However, it is challenging to grow thin tungsten films with such a low transition. The quantum effect of superconductivity is very sensitive to even small changes in the material properties, resulting from varying deposition conditions. Therefore, it is crucial to investigate and understand the influences of differing deposition conditions in order to grow TES of reproducible properties. In thin films especially crystal structure, grain size, impurities and film stress are known to influence superconductivity. In the framework of this thesis, a production facility for thin tungsten films, that is capable of mass production has successfully been set up. It proved to be capable of producing films with transition temperatures of 15 mK, meeting the requirements of the CRESST experiment. However, due to a lack of reliable transition curve measurements, influences of the deposition conditions on the superconductive properties and their reproducibility could not be investigated. Instead several analysis techniques for investigations of the crystal phase, impurity inclusions, surface morphology, electrical resistance and film stress have been performed. These techniques provide knowledge about film properties, that are known to affect superconductivity. Especially the influence of the substrate temperature during deposition on these film properties were studied. The results of the analysis techniques are specific to the deposition system that has been set up for this work and might differ quantitatively for other deposition systems