2,350 research outputs found
Bungeās Mathematical Structuralism Is Not a Fiction
In this paper, I explore Bungeās fictionism in philosophy of mathematics. After an overview of Bungeās views, in particular his mathematical structuralism, I argue that the comparison between mathematical objects and fictions ultimately fails. I then sketch a different ontology for mathematics, based on Thomassonās metaphysical work. I conclude that mathematics deserves its own ontology, and that, in the end, much work remains to be done to clarify the various forms of dependence that are involved in mathematical knowledge, in particular its dependence on mental/brain states and material objects
Axiomatic foundations of quantum mechanics revisited: the case for systems
We present an axiomatization of non-relativistic Quantum Mechanics for a
system with an arbitrary number of components. The interpretation of our system
of axioms is realistic and objective. The EPR paradox and its relation with
realism is discussed in this framework. It is shown that there is no
contradiction between realism and recent experimental results.Comment: submitted to International Journal of Theoretical Physics, uses
Latex, no figure
Four simplified gradient elasticity models for the simulation of dispersive wave propagation
Gradient elasticity theories can be used to simulate dispersive wave propagation as it occurs in heterogeneous materials. Compared to the second-order partial differential equations of classical elasticity, in its most general format gradient elasticity also contains fourth-order spatial, temporal as well as mixed spatial temporal derivatives. The inclusion of the various higher-order terms has been motivated through arguments of causality and asymptotic accuracy, but for numerical implementations it is also important that standard discretization tools
can be used for the interpolation in space and the integration in time. In this paper, we will formulate four different simplifications of the general gradient elasticity theory. We will study the dispersive properties of the models, their causality according to Einstein and their behavior in simple initial/boundary value problems
Tomographic filtering of highāresolution mantle circulation models: Can seismic heterogeneity be explained by temperature alone?
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95052/1/ggge1509.pd
Parmenides reloaded
I argue for a four dimensional, non-dynamical view of space-time, where
becoming is not an intrinsic property of reality. This view has many features
in common with the Parmenidean conception of the universe. I discuss some
recent objections to this position and I offer a comparison of the Parmenidean
space-time with an interpretation of Heraclitus' thought that presents no major
antagonism.Comment: 11 pages, accepted for publication in Foundations of Scienc
High-Resolution Imaging of Texture and Microstructure by the Moving Detector Method
In order to describe texture and microstructure of a polycrystalline material completely, crystal orientation g={?1F?2} must be known in all points x={x1?x2?x3} of the material. This can be achieved by locationresolved diffraction of high-energy, i.e. short-wave, X-rays from synchrotron sources. Highest resolution in the orientation- as well as the location-coordinates can be achieved by three variants of a detector sweeping technique in which an area detector is continuously moved during exposure. This technique results in two-dimensionally continuous images which are sections and projections of the six-dimensional orientation location space. Further evaluation of these images depends on whether individual grains are resolved in them or not. Because of the high penetration depth of high-energy synchrotron radiation in matter, this technique is also, and particularly, suitable for the investigation of the interior of big samples.researc
Dark matter search by exclusive studies of X-rays following WIMPs nuclear interactions
It is shown that weakly interacting massive particles (WIMPs), which are
possible cold dark matter candidates, can be studied by exclusive measurements
of X-rays following WIMPs nuclear interactions. Inner-shell atomic electrons
are ionized through WIMP-nuclear interaction, and then mono-energetic X-rays
are emitted when they are filled by outer-shell electrons. The number of
inner-shell holes amounts to as large as one per five nuclear recoils for
K-shell and several per recoil for L-shell in the case of medium heavy target
nuclei interacting with 100-300 GeV WIMPs. Then the K and L X-ray peaks show up
in the 5-50 keV region. Consequently exclusive studies of the X-rays in
coincidence with the nuclear recoils and the ionization electrons are found to
provide excellent opportunities to detect WIMPs such as the Lightest Super
Symmetric Particles (LSP)Comment: 13 pages, 2 table
Exact Philosophy of Space-Time
Starting from Bunge's (1977) scientific ontology, we expose a materialistic
relational theory of space-time, that carries out the program initiated by
Leibniz, and provides a protophysical basis consistent with any rigorous
formulation of General Relativity. Space-time is constructed from general
concepts which are common to any consistent scientific theory and they are
interpreted as emergent properties of the greatest assembly of things, namely,
the world.Comment: 13 pages, 3 figures. Version compatible with the published one. arXiv
admin note: substantial text overlap with arXiv:gr-qc/971006
Crossāscale seismic anisotropy analysis in metamorphic rocks from the COSCā1 borehole in the Scandinavian Caledonides
Metamorphic and deformed rocks in thrust zones show particularly high seismic anisotropy causing challenges for seismic imaging and interpretation. A good example is the Seve Nappe Complex in central Sweden, an old exhumed orogenic thrust zone that is characterized by a strong but incoherent seismic reflectivity and considerable seismic anisotropy. However, only little is known about their origin in relation to composition and structural influences on measurements at different seismic scales. Here, we present a new integrative study of crossāscale seismic anisotropy analyses combining mineralogical composition, microstructural analyses and seismic laboratory experiments from the COSCā1 borehole, which sampled a 2.5 kmādeep section of metamorphic rocks deformed in an orogenic root now preserved in the Lower Seve Nappe. While there is strong crystallographic preferred orientation in most samples in general, variations in anisotropy depend mostly on bulk mineral composition and dominant core lithology as shown by a strong correlation between these. This relationship enables to identify three distinct seismic anisotropy facies providing a continuous anisotropy profile along the borehole. Moreover, comparison of laboratory seismic measurements and electronābackscatter diffraction data reveals a strong scaleādependence, which is more pronounced in the highly deformed, heterogeneous samples. This highlights the need for comprehensive crossāvalidation of microscale anisotropy analyses with additional lithological data when integrating seismic anisotropy over seismic scales
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