30 results on '"Geons"'
Search Results
2. Urban green valuation integrating biophysical and qualitative aspects
- Author
-
Stefan Lang
- Subjects
Green perception ,telic representation ,geons ,regionalization ,VHR satellite data ,geonalytics ,Oceanography ,GC1-1581 ,Geology ,QE1-996.5 - Abstract
Urban green mapping has become an operational task in city planning, urban land management, and quality of life assessments. As a multi-dimensional, integrative concept, urban green comprising several ecological, socio-economic, and policy-related aspects. In this paper, the author advances the representation of urban green by deriving scale-adapted, policy-relevant units. These so-called geons represent areas of uniform green valuation under certain size and homogeneity constraints in a spatially explicit representation. The study accompanies a regular monitoring scheme carried out by the urban municipality of the city of Salzburg, Austria, using optical satellite data. It was conducted in two stages, namely SBG_QB (10.2 km², QuickBird data from 2005) and SBG_WV (140 km², WorldView-2 data from 2010), within the functional urban area of Salzburg. The geon delineation was validated by several quantitative measures and spatial analysis techniques, as well as ground documentation, including panorama photographs and visual interpretation. The spatial association pattern was assessed by calculating Global Moran’s I with incremental search distances. The final geonscape, consisting of 1083 units with an average size of 13.5 ha, was analyzed by spatial metrics. Finally, categories were derived for different types of functional geons. Future research paths and improvements to the described strategy are outlined.
- Published
- 2018
- Full Text
- View/download PDF
3. Landslide Susceptibility Mapping for Austria Using Geons and Optimization with the Dempster-Shafer Theory.
- Author
-
Gudiyangada Nachappa, Thimmaiah, Tavakkoli Piralilou, Sepideh, Ghorbanzadeh, Omid, Shahabi, Hejar, and Blaschke, Thomas
- Subjects
DEMPSTER-Shafer theory ,MATHEMATICAL optimization ,GRAVITONS ,LANDSLIDES ,RECEIVER operating characteristic curves ,LAND cover - Abstract
Landslide susceptibility mapping (LSM) can serve as a basis for analyzing and assessing the degree of landslide susceptibility in a region. This study uses the object-based geons aggregation model to map landslide susceptibility for all of Austria and evaluates whether an additional implementation of the Dempster–Shafer theory (DST) could improve the results. For the whole of Austria, we used nine conditioning factors: elevation, slope, aspect, land cover, rainfall, distance to drainage, distance to faults, distance to roads, and lithology, and assessed the performance and accuracy of the model using the area under the curve (AUC) for the receiver operating characteristics (ROC). We used three scale parameters for the geons model to evaluate the impact of the scale parameter on the performance of LSM. The results were similar for the three scale parameters. Applying the Dempster–Shafer theory could significantly improve the results of the object-based geons model. The accuracy of the DST-derived LSM for Austria improved and the respective AUC value increased from 0.84 to 0.93. The resulting LSMs from the geons model provide meaningful units independent of administrative boundaries, which can be beneficial to planners and policymakers. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
4. Gravitational Waves. Introduction to the Gravitational Waves Equation
- Author
-
Wim Vegt
- Subjects
Quantum Field Theory ,Gravitational Lensing ,General Relativity ,Gravitational-Electromagnetic Interaction ,GEONs ,Gravitational Wave Equation - Abstract
Gravitational Waves represent the transport of Gravitational Energy through Space. Equation (101) and in particular (107) and (108) represent the “Gravitational Wave Equation”. The article presents a new theory in physics which explains the interaction between gravity and light with mathematical results close to General Relativity (15 digits beyond the decimal point equal result) and unifies General Relativity with Quantum Physics by the fundamental elementary particle: the GEON. The GEON [1] is a fundamental solution of the relativistic quantum mechanical Dirac equation (Quantum Physics) and the confinement has been controlled by the fundamental interaction between Gravity and Light (General Relativity). The GEON is the most fundamental elementary particle and can be created by the compression of light into extremely high densities. The GEON appears when an equilibrium has been established between the expanding radiation pressure of light and the confining gravitational force of light. The GEON is the fundamental solution of the relativistic quantum mechanical Dirac equation. For this reason the GEON particle unifies Quantum Physics with General Relativity. The confinement of GEONS is only possible at discrete values. (Quantisation of Energy, Light and Gravity). The GEON carries the mass inside the structures of matter (Elementary Particles). The radius of a GEON with the mass of a proton (1.67×10-27 kg) equals 3 10-58 [m]. [30] PlotGraph 3, page 24. The GEON represents the creation of matter/anti-matter by Electromagnetic-Gravitational interaction. The new theory in physics has been based on the “divergence-free linear 4-dimensional stress-energy tensor in the Minkowski Space”. The difference between Einstein’s General Relativity and this theory is the different approach. Einstein has deformed (non-linear and non-divergence free) the “4-dimensional Stress-Energy Tensor” by introducing the curved 4-dimensional Riemannian Manifold to explain the interaction between Gravity and Light. The new theory describes the interaction between different fields (Electric, Magnetic and Gravitational) by identical interaction terms, generated by the separate divergence and the separate rotation of the different fields. (equation 24). The theory describes “Electromagnetic-Gravitational Interaction”, “Magnetic-Gravitational Interaction” and “Electric-Gravitational Interaction”. In this new theory particles do not interact with fields. The interaction between an electric charged particle and an electric field is not the interaction between a particle and a field but it is the interaction between the electric field of the particle interacting with the other electric field. Every interaction is an interaction between fields. Electric Fields interact with Electric Fields , Magnetic Fields interact with Magnetic Fields and Gravitational Fields interact with Gravitational Fields. Electric Fields interact with 1st order Lorentz Transformed Magnetic Fields. Magnetic Fields interact with 1st order Lorentz Transformed Electric Fields. Gravitational Fields have been created by accelerated (Confined) 2nd order Lorentz Transformed Electromagnetic Fields. Electromagnetic Fields interact with 2nd order Lorentz Transformed Gravitational Fields. Gravitational Fields interact with 2nd order Lorentz Transformed (Confined) Electromagnetic Fields. This has been called: “Electromagnetic-Gravitational Interaction”.
- Published
- 2023
5. GEON particle, the missing link between Quantum Physics and General Relativity
- Author
-
Wim Vegt
- Subjects
General Relativity ,GEONs ,Quantum Field Theory ,Gravitational-Electromagnetic Interaction ,Quantum Physics ,Gravitational RedShift ,RedShift ,BlueShift ,Galaxies ,Elementary Particles - Abstract
The article presents a new theory in physics which explains the interaction between gravity and light with mathematical results close to General Relativity (15 digits beyond the decimal point equal result) and unifies General Relativity with Quantum Physics by the fundamental elementary particle: the GEON. The GEON [1] is a fundamental solution of the relativistic quantum mechanical Dirac equation (Quantum Physics) and the confinement has been controlled by the fundamental interaction between Gravity and Light (General Relativity). The GEON is the most fundamental elementary particle and can be created by the compression of light into extremely high densities. The GEON appears when an equilibrium has been established between the expanding radiation pressure of light and the confining gravitational force of light. The GEON is the fundamental solution of the relativistic quantum mechanical Dirac equation. For this reason the GEON particle unifies Quantum Physics with General Relativity. The confinement of GEONS is only possible at discrete values. (Quantisation of Energy, Light and Gravity). The GEON carries the mass inside the structures of matter (Elementary Particles). The radius of a GEON with the mass of a proton (1.67×10-27 kg) equals 3 10-58 [m]. [30] PlotGraph 3, page 24 The new theory in physics has been based on the “divergence-free linear 4-dimensional stress-energy tensor in the Minkowski Space”. The difference between Einstein’s General Relativity and this theory is the different approach. Einstein has deformed (non-linear and non-divergence free) the “4-dimensional Stress-Energy Tensor” by introducing the curved 4-dimensional Riemannian Manifold to explain the interaction between Gravity and Light. The new theory describes the interaction between different fields (Electric, Magnetic and Gravitational) by identical interaction terms, generated by the separate divergence and the separate rotation of the different fields. (equation 24) The conclusion of the new theory is that “divergence-free” and “rotation-free” fields do not interact. When Isaac Newton published his 3 famous equations which became the foundation of Classical Dynamics, he was not aware that he was building the first elemental blocks for the Stress-Energy Tensor in the 4-dimensional Minkowski Space. When James Clerk Maxwell published his 4 famous equations which became the foundation for Classical Electrodynamics, he was not aware that he was building new blocks for the Stress-Energy Tensor in the 4-dimensional Minkowski Space. When Paul Dirac published his famous equation which became the foundation of Relativistic Quantum Physics, he was not aware that he was building further on blocks for the Stress-Energy Tensor in the 4-dimensional Minkowski Space. It was Albert Einstein who was one of the first physicists who discovered the importance of the Stress-Energy Tensor to describe in a mathematical way the interaction between Electromagnetic Radiation and a Gravitational Field. Because there was no match, Einstein deformed the Divergence-Free Linear “Stress-Energy Tensor” by deforming Space and Time. Using curved Riemannian manifolds, he deformed the fundamental Tensor in physics in such a way that he found a very special Mathematics to describe the interaction between Electromagnetic Radiation (Light) and a Gravitational Field. The Theory of General Relativity. This became a fundamental problem in physics. By deforming the fundamental building block in physics (the Divergence-Free Linear “Stress-Energy Tensor), there is no match anymore in the fundamental mainstreams in physics (classical mechanics, electrodynamics, quantum physics and general relativity). Classical Mechanics has no match with Classical Electrodynamics. Classical Electrodynamics has no match with Relativistic Quantum Physics. Relativistic Quantum Physics has no match with General Relativity. It is important to distinguish the “Physical Reality” from a Mathematical Description of it (which is in general an approach). The scalar curvature (or the Ricci scalar) is a measure of the curvature of a Riemannian manifold. Einstein used a curved Riemannian manifold to describe “Gravitational-Electromagnetic Interaction”. But the physics beyond this is the interaction between the different fields. It is possible to describe this in different ways. This new theory demonstrates a more direct approach in the force densities acting between different fields expressed by equation (24). This new theory starts with the Divergence-Free Linear “Stress-Energy Tensor” in the 4-dimensional Minkowski Space. And from this unique Divergence-Free “Stress-Energy Tensor” follows Classical Mechanics, Classical Electrodynamics, Relativistic Quantum Physics and General Relativity. Bringing back the necessary unity in physics. Theories which unify Quantum Physics and General Relativity, like “String Theory”, predict the non-constancy of natural constants. Accurate observations of the NASA Messenger [11] observe in time a value for the gravitational constant “G” which constrains until ( /G to be < 4 × 10-14 per year) . One of the characteristics of the New Theory is the “Constant Value” in time for the Gravitational Constant “G”. A second experiment to test the New Theory is the effect of “Gravitational RedShift” [2]. The “Gravitational RedShift” between an observatory on Earth (Radius = 6 106 [m]) and a Satellite in a Galileo Orbit (Radius = 23222 103 [m]) according “General Relativity”: The “Gravitational RedShift” between an observatory on Earth (Radius = 6 106 [m]) and a Satellite in a Galileo Orbit (Radius = 23222 103 [m]) according “The Proposed Theory”:  
- Published
- 2023
6. The Fundamental Choice in Physics between a non-linear and non-divergence Free 'Stress-Energy Tensor' and the linear Divergence-Free 'Stress-Energy Tensor' in the 4-dimensional Minkowski Space
- Author
-
Wim Vegt
- Subjects
General Relativity ,GEONs ,Quantum Field Theory ,Gravitational-Electromagnetic Interaction ,Gravity ,Gravitational RedShift' ,RedShift ,Galaxies - Abstract
This article describes a new theory in physics which has been based on the “divergence-free linear 4-dimensional stress-energy tensor in the Minkowski Space”. The difference between Einstein’s General Relativity and this theory is the different approach. Einstein has deformed (non-linear and non-divergence free) the “4-dimensional Stress-Energy Tensor” by introducing the curved 4-dimensional Riemannian Manifold to explain the interaction between Gravity and Light. The new theory describes the interaction between different fields (Electric, Magnetic and Gravitational) by identical interaction terms, generated by the separate divergence and the separate rotation of the different fields. (equation 24) The conclusion of the new theory is that “divergence-free” and “rotation-free” fields do not interact. When Isaac Newton published his 3 famous equations which became the foundation of Classical Dynamics, he was not aware that he was building the first elemental blocks for the Stress-Energy Tensor in the 4-dimensional Minkowski Space. When James Clerk Maxwell published his 4 famous equations which became the foundation for Classical Electrodynamics, he was not aware that he was building new blocks for the Stress-Energy Tensor in the 4-dimensional Minkowski Space. When Paul Dirac published his famous equation which became the foundation of Relativistic Quantum Physics, he was not aware that he was building further on blocks for the Stress-Energy Tensor in the 4-dimensional Minkowski Space. It was Albert Einstein who was one of the first physicists who discovered the importance of the Stress-Energy Tensor to describe in a mathematical way the interaction between Electromagnetic Radiation and a Gravitational Field. But because there was no match, Einstein deformed the Divergence-Free Linear “Stress-Energy Tensor” by deforming Space and Time. He deformed this Tensor in such a way that he found a very special Mathematics to describe the interaction between Electromagnetic Radiation (Light) and a Gravitational Field. The Theory of General Relativity. And that became a problem. Because Einstein deformed the fundamental building block in physics (the Divergence-Free Linear “Stress-Energy Tensor), nothing fits anymore. Classical Mechanics has no match with Classical Electrodynamics. Classical Electrodynamics has no match with Relativistic Quantum Physics. Relativistic Quantum Physics has no match with General Relativity. It is important to distinguish the “Physical Reality” from a Mathematical Description of it (which is in general an approach). The scalar curvature (or the Ricci scalar) is a measure of the curvature of a Riemannian manifold. Einstein used a curved Riemannian manifold to describe “Gravitational-Electromagnetic Interaction”. But the physics beyond this is the interaction between the different fields. It is possible to describe this in different ways. This new theory demonstrates a more direct approach in the force densities acting between different fields expressed by equation (24). This new theory starts with the Divergence-Free Linear “Stress-Energy Tensor” in the 4-dimensional Minkowski Space. And from this unique Divergence-Free “Stress-Energy Tensor” follows Classical Mechanics, Classical Electrodynamics, Relativistic Quantum Physics and General Relativity. Bringing back the necessary unity in physics. Theories which unify Quantum Physics and General Relativity, like “String Theory”, predict the non-constancy of natural constants. Accurate observations of the NASA Messenger [11] observe in time a value for the gravitational constant “G” which constrains until ( /G to be < 4 × 10-14 per year) . One of the characteristics of the New Theory is the “Constant Value” in time for the Gravitational Constant “G”. A second experiment to test the New Theory is the effect of “Gravitational RedShift” [2]. The “Gravitational RedShift” between an observatory on Earth (Radius = 6 106 [m]) and a Satellite in a Galileo Orbit (Radius = 23222 103 [m]) according “General Relativity”: The “Gravitational RedShift” between an observatory on Earth (Radius = 6 106 [m]) and a Satellite in a Galileo Orbit (Radius = 23222 103 [m]) according “The Proposed Theory”: describes a new theory in physics which has been based on the“divergence-free linear 4-dimensional stress-energy tensor in the Minkowski Space”.The difference between Einstein’s General Relativity and this theory is the differentapproach.Einstein has deformed(non-linear and non-divergence free)the “4-dimensional Stress-Energy Tensor” by introducing the curved 4-dimensionalRiemannian Manifold to explain the interaction between Gravity and Light. The newtheory describes the interaction between different fields (Electric, Magnetic andGravitational) by identical interaction terms,generated by theseparatedivergenceand the separaterotation of the different fields. (equation 24) The conclusion of thenew theory is that “divergence-free” and “rotation-free” fields do not interact.
- Published
- 2023
- Full Text
- View/download PDF
7. Quantum Transitions in GEONs
- Author
-
Wim Vegt
- Subjects
General Relativity ,GEONs ,Quantum Field Theory ,Gravitational-Electromagnetic Interaction - Abstract
Albert Einstein has introduced a new understanding of light by introducing the concept of the “photon”. This concept originated (1905) in Albert Einstein’s explanation of the photoelectric effect, in which he proposed the existence of discrete energy packets during the transmission of light. Because photons propagate with the speed of light, it is a necessary requirement that the rest-mass of photons equals zero. Recently experiments have resulted in the observation that the rest mass of a photon does not equal zero. [10]. Einstein’s solution to explain the interaction between gravity and light (particles with rest-mass zero, photons) was a curved space-time continuum. A Space-Time continuum curved due to a gravitational field. The assumption of the zero-mass of photons had been based on Maxwell’s assumption that electromagnetic waves do not carry mass and do not generate a gravitational field.This article describes electromagnetic fields which do carry mass (inertia) ([12] and equation (92)) and do generate a gravitational field, expressed in the terms B-1 (inertia) and B-6 (Gravity) in equation 23. In this way Newton’s Classical Dynamics will be unified with Maxwell’s Electrodynamics and Einstein’s General Relativity. Extending Newton’s 3-dimensional Equilibrium in Classical Mechanics into a model of confined electromagnetic energy within a 4-dimensional Equilibrium will unify Classical Mechanics with Relativistic Quantum Physics (Dirac Equation).The research has been focussed to unify the four fundamental theories in physics. Isaac Newton’s Classical Mechanics, James Clerk Maxwell’s Electrodynamics, Quantum Physics (Niels Bohr, Paul Dirac, Werner Heisenberg) and Albert Einstein’s Theory of General Relativity. These four fundamental theories also mark the different periods when they have been created and a fundamentally different way of thinking at those times. To unify these four principles of Physics, it is necessary to link electromagnetism and gravitation. Here it is proposed that the 2-dimensional confinement of electromagnetic radiation (a beam of light) creates its own gravitational field, and that field will interact with other gravitational fields. To illustrate the utility of this theory, an example has been discussed with regard to the measured gravitational redshift associated with Earth’s gravity. This Theory has been called “Quantum Light Theory”. Theories which unify Quantum Physics and General Relativity, like “String Theory”, predict the non-constancy of natural constants. Accurate observations of the NASA Messenger [11] observe in time a value for the gravitational constant “G” which constrains until ( /G to be < 4 × 10-14 per year) . One of the characteristics of the New Theory is the “Constant Value” in time for the Gravitational Constant “G”. This article describes the energy transitions within GEONs (Published in 1955 by J. A.Wheeler).
- Published
- 2023
8. Recognising three-dimensional objects using parameterized volumetric models
- Author
-
Borges, Dibio Leandro, Fisher, Robert B., Trucco, Manuel., and Hallam, John
- Subjects
006.3 ,volumetric models ,3-D objects ,Radical Basis Function ,Kalman Filter technique ,Interpretation Tree algorithm ,geons - Abstract
This thesis addressed the problem of recognizing 3-D objects, using shape information extracted from range images, and parameterized volumetric models. The domains of the geometric shapes explored is that of complex curved objects with articulated parts, and a great deal of similarity between some of the parts. These objects are exemplified by animal shapes, however the general characteristics and complexity of these shapes are present in a wide range of other natural and man-made objects. In model-based object recognition three main issues constrain the design of a complete solution: representation, feature extraction, and interpretation. this thesis develops an integrated approach that addresses these three issues in the context of the above mentioned domain of objects. For representation I propose a composite description using globally deformable superquadratics and a set of volumetric primitives called geons: this description is shown to have representational and discriminative properties suitable for recognition. Feature extraction comprises a segmentation process which develops a method to extract a parts-based description of the objects as assemblies of defoemable superquadratics. Discontinuity points detected from the images are linked using 'active contour' minimization technique, and deformable superquadratic models are fitted to the resulting regions afterwards. Interpretation is split into three components: classification of parts, matching, and pose estimation. A Radical Basis Function [RBF] classifier algoritm is presented in order to classify the superquadratics shapes derived from the segmentation into one of twelve geon classes. The matching component is decomposed into two stages: first, an indexing scheme which makes effective use of the output of the [RBF] classifier in order to direct the search to the models which contain the parts identified. this makes the search more efficient, and with a model library that is organised in a meaningful and robust way, permits growth without compromising performance. Second, a method is proposed where the hypotheses picked from the index are searched using an Interpretation Tree algorithm combined with a quality measure to evaluate the bindings and the final valid hypotheses based on Possibility Theory, or Theory of Fuzzy Sets. The valid hypotheses ranked by the matching process are then passed to the pose estimation module. This module uses a Kalman Filter technique that includes the constraints on the articulations as perfect measurements, and as such provides a robust and generic way to estimate pose in object domains such as the one approached here. These techniques are then combined to produce an integrated approach to the object recognition task. The thesis develops such an integrated approach, and evaluates its perfomance inthe sample domain. Future extensions of each technique and the overall integration strategy are discussed.
- Published
- 1996
9. Geons
- Author
-
Dickinson, Sven J., Biederman, Irving, and Ikeuchi, Katsushi, editor
- Published
- 2014
- Full Text
- View/download PDF
10. Trapped Gravitational Waves in Jackiw–Teitelboim Gravity
- Author
-
Jeong-Myeong Bae, Ido Ben-Dayan, Marcelo Schiffer, Gibum Yun, and Heeseung Zoe
- Subjects
gravitational waves ,geons ,Jackiw-Teitelboim gravity ,Elementary particle physics ,QC793-793.5 - Abstract
We discuss the possibility that gravitational fluctuations (“gravitational-waves”) are trapped in space by gravitational interactions in two dimensional Jackiw–Teitelboim gravity. In the standard geon (gravitational electromagnetic entity) approach, the effective energy is entirely deposited in a thin layer, the active region, that achieves spatial self-confinement and raises doubts about the geon’s stability. In this paper we relinquish the “active region” approach and obtain self-confinement of “gravitational waves” that are trapped by the vacuum geometry and can be stable against the backreaction due to metric fluctuations.
- Published
- 2021
- Full Text
- View/download PDF
11. Urban green valuation integrating biophysical and qualitative aspects.
- Author
-
Lang, Stefan
- Subjects
URBAN ecology (Sociology) ,SUSTAINABLE development - Abstract
Urban green mapping has become an operational task in city planning, urban land management, and quality of life assessments. As a multi-dimensional, integrative concept, urban green comprising several ecological, socio-economic, and policy-related aspects. In this paper, the author advances the representation of urban green by deriving scale-adapted, policy-relevant units. These so-called geons represent areas of uniform green valuation under certain size and homogeneity constraints in a spatially explicit representation. The study accompanies a regular monitoring scheme carried out by the urban municipality of the city of Salzburg, Austria, using optical satellite data. It was conducted in two stages, namely SBG_QB (10.2 km², QuickBird data from 2005) and SBG_WV (140 km², WorldView-2 data from 2010), within the functional urban area of Salzburg. The geon delineation was validated by several quantitative measures and spatial analysis techniques, as well as ground documentation, including panorama photographs and visual interpretation. The spatial association pattern was assessed by calculating Global Moran’s I with incremental search distances. The final geonscape, consisting of 1083 units with an average size of 13.5 ha, was analyzed by spatial metrics. Finally, categories were derived for different types of functional geons. Future research paths and improvements to the described strategy are outlined. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
12. Mapping-Class Groups of 3-Manifolds in Canonical Quantum Gravity
- Author
-
Giulini, Domenico, Fauser, Bertfried, editor, Tolksdorf, Jürgen, editor, and Zeidler, Eberhard, editor
- Published
- 2007
- Full Text
- View/download PDF
13. Modeling Hotspots of Climate Change in the Sahel Using Object-Based Regionalization of Multidimensional Gridded Datasets
- Author
-
Michael Hagenlocher, Stefan Lang, Daniel Holbling, Dirk Tiede, and Stefan Kienberger
- Subjects
Climate change ,data integration ,geons ,object-based image analysis (OBIA) ,Sahel ,spatial composite indicators ,Ocean engineering ,TC1501-1800 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
The population of subsaharan Africa, and particularly of the countries of the Sahel and western Africa, is one of the most vulnerable to climate change and climate-related extreme events. To provide updated information for targeted climate change adaptation measures, we modeled hotspots of climate change and related extreme events in an integrative manner. This was achieved by constructing a spatial composite indicator of cumulative climate change impact, which integrates four climate- and hazard-related subindicators: seasonal temperature trends, seasonal precipitation trends, drought occurrences, and major flood events. The analysis is based on time-series of freely available continuous, gridded geo-spatial datasets, including remote sensing data. The aggregation of the four subindicators was performed by making use of a regionalization approach, based on segmentation techniques widely used in the remote sensing community in the field of object-based image analysis. Following the approach presented in this paper, 19 hotspots with most severe climatic changes were identified, evaluated, and mapped. The method enables not only the prioritization of intervention areas, but also allows decomposing the identified hotspots into their underlying subindicators, and thus additional information for effective climate change adaptation measures can be provided.
- Published
- 2014
- Full Text
- View/download PDF
14. From the Flamm-Einstein-Rosen bridge to the modern renaissance of traversable wormholes.
- Author
-
Lobo, Francisco S. N.
- Subjects
- *
EINSTEIN field equations , *WORMHOLES (Physics) , *GRAVITONS , *GENERAL relativity (Physics) , *SPACETIME , *GRAVITATIONAL fields - Abstract
We consider the possibility of multiply-connected spacetimes, ranging from the Flamm-Einstein-Rosen bridge, geons, and the modern renaissance of traversable wormholes. A fundamental property in wormhole physics is the flaring-out condition of the throat, which through the Einstein field equation entails the violation of the null energy condition (NEC). In the context of modified theories of gravity, it has also been shown that the normal matter can be imposed to satisfy the energy conditions, and it is the higher order curvature terms, interpreted as a gravitational fluid, that sustain these nonstandard wormhole geometries, fundamentally different from their counterparts in general relativity (GR). We explore interesting features of these geometries, in particular, the physical properties and characteristics of these 'exotic spacetimes'. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
15. The quantum, the geon and the crystal.
- Author
-
Olmo, Gonzalo J. and Rubiera-Garcia, Diego
- Subjects
- *
BLACK holes , *GRAVITATIONAL collapse , *ELECTROMAGNETIC fields , *PARTICLE detectors , *GRAVITATION , *ASTROPHYSICS , *METAPHYSICAL cosmology - Abstract
Effective geometries arising from a hypothetical discrete structure of spacetime can play an important role in the understanding of the gravitational physics beyond General Relativity (GR). To discuss this question, we make use of lessons from crystalline systems within solid state physics, where the presence of defects in the discrete microstructure of the crystal determine the kind of effective geometry needed to properly describe the system in the macroscopic continuum limit. In this work, we study metric-affine theories with nonmetricity and torsion, which are the gravitational analog of crystalline structures with point defects and dislocations. We consider a crystal-motivated gravitational action and show the presence of topologically nontrivial structures (wormholes) supported by an electromagnetic field. Their existence has important implications for the quantum foam picture and the effective gravitational geometries. We discuss how the dialogue between solid state physics systems and modified gravitational theories can provide useful insights on both sides. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
16. Trapped Gravitational Waves in Jackiw–Teitelboim Gravity
- Author
-
Ido Ben-Dayan, Jeong-Myeong Bae, Marcelo Schiffer, Gibum Yun, and Heeseung Zoe
- Subjects
Physics ,Gravity (chemistry) ,Physics::General Physics ,lcsh:QC793-793.5 ,010308 nuclear & particles physics ,Gravitational wave ,geons ,lcsh:Elementary particle physics ,General Physics and Astronomy ,Space (mathematics) ,01 natural sciences ,Stability (probability) ,Gravitation ,Jackiw–Teitelboim gravity ,High Energy Physics::Theory ,General Relativity and Quantum Cosmology ,gravitational waves ,Quantum electrodynamics ,0103 physical sciences ,Metric (mathematics) ,Jackiw-Teitelboim gravity ,Geon (physics) ,010303 astronomy & astrophysics - Abstract
We discuss the possibility that gravitational fluctuations (“gravitational-waves”) are trapped in space by gravitational interactions in two dimensional Jackiw–Teitelboim gravity. In the standard geon (gravitational electromagnetic entity) approach, the effective energy is entirely deposited in a thin layer, the active region, that achieves spatial self-confinement and raises doubts about the geon’s stability. In this paper we relinquish the “active region” approach and obtain self-confinement of “gravitational waves” that are trapped by the vacuum geometry and can be stable against the backreaction due to metric fluctuations.
- Published
- 2021
17. Modeling Hotspots of Climate Change in the Sahel Using Object-Based Regionalization of Multidimensional Gridded Datasets.
- Author
-
Hagenlocher, Michael, Lang, Stefan, Holbling, Daniel, Tiede, Dirk, and Kienberger, Stefan
- Abstract
The population of subsaharan Africa, and particularly of the countries of the Sahel and western Africa, is one of the most vulnerable to climate change and climate-related extreme events. To provide updated information for targeted climate change adaptation measures, we modeled hotspots of climate change and related extreme events in an integrative manner. This was achieved by constructing a spatial composite indicator of cumulative climate change impact, which integrates four climate- and hazard-related subindicators: seasonal temperature trends, seasonal precipitation trends, drought occurrences, and major flood events. The analysis is based on time-series of freely available continuous, gridded geo-spatial datasets, including remote sensing data. The aggregation of the four subindicators was performed by making use of a regionalization approach, based on segmentation techniques widely used in the remote sensing community in the field of object-based image analysis. Following the approach presented in this paper, 19 hotspots with most severe climatic changes were identified, evaluated, and mapped. The method enables not only the prioritization of intervention areas, but also allows decomposing the identified hotspots into their underlying subindicators, and thus additional information for effective climate change adaptation measures can be provided. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
18. Landslide Susceptibility Mapping for Austria Using Geons and Optimization with the Dempster–Schafer Theory
- Author
-
Nachappa, Thimmaiah Gudiyangada, Piralilou, Sepideh Tavakkoli, Ghorbanzadeh, Omid, Shahabi, Hejar, and Blaschke, Thomas
- Subjects
natural hazards ,geons ,landslide susceptibility mapping ,Dempster–Schafer theory ,object-based - Abstract
Landslide susceptibility mapping (LSM) can serve as a basis for analyzing and assessing the degree of landslide susceptibility in a region. This study uses the object-based geons aggregation model to map landslide susceptibility for all of Austria and evaluates whether an additional implementation of the Dempster&ndash, Shafer theory (DST) could improve the results. For the whole of Austria, we used nine conditioning factors: elevation, slope, aspect, land cover, rainfall, distance to drainage, distance to faults, distance to roads, and lithology, and assessed the performance and accuracy of the model using the area under the curve (AUC) for the receiver operating characteristics (ROC). We used three scale parameters for the geons model to evaluate the impact of the scale parameter on the performance of LSM. The results were similar for the three scale parameters. Applying the Dempster&ndash, Schafer theory could significantly improve the results of the object-based geons model. The accuracy of the DST-derived LSM for Austria improved and the respective AUC value increased from 0.84 to 0.93. The resulting LSMs from the geons model provide meaningful units independent of administrative boundaries, which can be beneficial to planners and policymakers.
- Published
- 2019
- Full Text
- View/download PDF
19. An Example 4-Geon.
- Author
-
Watson, R. E. S.
- Subjects
- *
GRAVITY waves , *RELATIVITY (Physics) , *QUANTUM logic , *WORLD line (Physics) , *AXIOMS , *QUANTUM theory - Abstract
It has been shown by Hadley that the logic of quantum mechanics is consistent with general relativity when closed time-like curves are permitted. This is done by hypothesising particles as 4-geons: particle-like solutions to Einstein's field equations with closed time-like curves. Hadley provides axioms that need to be satisfied for quantum logic to be possible. Here, a candidate 4-geon and an interpretation of quantum measurement is provided that satisfy all of Hadley's axioms. The candidate solution is based on the extended 'fast' Kerr-Newman singularity and a new interpretation of measurement. [ABSTRACT FROM AUTHOR]
- Published
- 2007
20. Dualities in Fractional Statistics.
- Author
-
Beciu, M. I.
- Subjects
- *
STATISTICS , *FRACTIONAL powers , *THERMODYNAMIC equilibrium , *MEAN field theory - Abstract
We first reobtain in a simpler way the Haldane fractional statistics at thermal equilibrium. We then show that the mean occupation number for fractional statistics is invariant to a group of duality transformations, a non-abelian subgroup of a fractional linear group. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
21. Part segmentation of objects in real images
- Author
-
Bilodeau, Guillaume-Alexandre and Bergevin, Robert
- Subjects
- *
GEOGRAPHICAL perception , *VOLUMETRIC analysis , *IMAGE processing - Abstract
This paper addresses one major aspect of a project aimed at the design of an image database query engine, where the images are searched at the 3D object-level. This approach is a novelty since image databases are usually searched by comparing colours, textures and 2D shapes of regions in the images. The main topic and contribution of this paper is a new method for object part segmentation, from constant-curvature contour primitives, that is suited to process images of objects in real scenes. The proposed method groups constant-curvature primitives using intermediate-level geometric relationships and object outline information. A detailed description of the method is presented along with validating experiments. [Copyright &y& Elsevier]
- Published
- 2002
- Full Text
- View/download PDF
22. Geons and (4+1) Gravity.
- Author
-
Houili, H. and Zerguini, T.
- Abstract
Gravitational-electromagnetic entities “geons” are singularity-free solutions of the Einstein-Maxwell equations. These structures in cylindrical symmetry are considered here through the noncompactified Kaluza-Klein theory which describes geometrically the gravitation field and its sources. [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
23. ASTRONOMICAL DISTANCES AND RADIOMETRIC DATING RELATED TO ADVANCED WAVES AND VECTOR-TENSOR-SCALAR GEOMETRY
- Author
-
Bartlett, Rodney
- Subjects
Radiometric dating ,Geometry ,Relativity ,Gravitational waves ,Electromagnetic waves ,Wick rotation ,Astronomy ,E=mc2 ,Inverse-square law ,Geons ,Geon ,Dark matter ,Dark energy - Abstract
Most people think science is exclusively about things like experiments, observations, and measurement. But to quote Professor of Mathematics Holmes Boynton who wrote World Book Encyclopedia’s “Geometry” article, “(Geometry) is important (later in the paragraph the quote is from, he uses the words “simple and easy to picture”) … because it shows students how to develop ideas by logical reasoning, rather than by observation, description, and measurement.” Therefore, it’s reasonable to use a simple geometry to help show that physics has uncovered a flaw with the results of all kinds of radioactive dating. Four years after publishing General Relativity (ie in 1919), Albert Einstein published a paper that asked "Do gravitational fields play an essential role in the structure of elementary particles?" (1) That paper was published in an attempt to clarify the inner workings of the atom. But it might well apply in the present paper. Central to radiometric dating’s overestimates are two things: a) mathematics’ vector-tensor-scalar geometry (a simple geometry conceived by the author) which, answering “yes” to Einstein’s 1919 paper, shows that gravitational and electromagnetic waves compose particles of matter; and b) the conclusion supported by last century’s physics that these waves contain “advanced” and “retarded” components travelling backwards and forwards in time (this is not science fiction but will be reconciled here with quantum entanglement as well as Einstein’s Relativity). Astronomers study gravitational and electromagnetic waves - it's natural to wonder if, for example, distances to astronomical objects have also been overestimated. Intriguingly, neutralizing the advanced waves should dramatically increase the health and lifespan of humans and all other species if it doesn't adversely affect anatomy and physiology ie if the retarded waves alone are sufficient for normal structure and function.This work relates waves to the Complex Number Plane and Wick rotation - different phases rotate from the x-axis to the so-called “imaginary” y-axis where they can produce the extra mass of another large-scale dimension (so-called Dark Matter) as well as the Dark Energy which the mass possesses.  
- Published
- 2019
- Full Text
- View/download PDF
24. Applied Sciences / Landslide Susceptibility Mapping for Austria Using Geons and Optimization with the Dempster-Shafer Theory
- Author
-
Gudiyangada Nachappa, Thimmaiah, Tavakkoli Piralilou, Sepideh, Ghorbanzadeh, Omid, Shahabi, Hejar, and Blaschke, Thomas
- Subjects
natural hazards ,geons ,landslide susceptibility mapping ,DempsterShafer theory ,object-based - Abstract
Landslide susceptibility mapping (LSM) can serve as a basis for analyzing and assessing the degree of landslide susceptibility in a region. This study uses the object-based geons aggregation model to map landslide susceptibility for all of Austria and evaluates whether an additional implementation of the DempsterShafer theory (DST) could improve the results. For the whole of Austria, we used nine conditioning factors: elevation, slope, aspect, land cover, rainfall, distance to drainage, distance to faults, distance to roads, and lithology, and assessed the performance and accuracy of the model using the area under the curve (AUC) for the receiver operating characteristics (ROC). We used three scale parameters for the geons model to evaluate the impact of the scale parameter on the performance of LSM. The results were similar for the three scale parameters. Applying the DempsterShafer theory could significantly improve the results of the object-based geons model. The accuracy of the DST-derived LSM for Austria improved and the respective AUC value increased from 0.84 to 0.93. The resulting LSMs from the geons model provide meaningful units independent of administrative boundaries, which can be beneficial to planners and policymakers. (VLID)4670298
- Published
- 2019
25. The logic of quantum mechanics derived from classical general relativity.
- Author
-
Hadley, Mark
- Abstract
For the first time it is shown that the logic of quantum mechanics can be derived from classical physics. An orthomodular lattice of propositions characteristic of quantum logic, is constructed for manifolds in Einstein’s theory of general relativity. A particle is modelled by a topologically non-trivial 4-manifold with closed timelike curves—a 4-geon, rather than as an evolving 3-manifold. It is then possible for both the state preparation and measurement apparatus to constrain the results of experiments. It is shown that propositions about the results of measurements can satisfy a non-distributive logic rather than the Boolean logic of classical systems. Reasonable assumptions about the role of the measurement apparatus leads to an orthomodular lattice of propositions characteristic of quantum logic. [ABSTRACT FROM AUTHOR]
- Published
- 1997
- Full Text
- View/download PDF
26. Sensitivity to Nonaccidental Configurations of Two-Line Stimuli
- Author
-
Jonas Kubilius, Charlotte Sleurs, and Johan Wagemans
- Subjects
Property (programming) ,lcsh:BF1-990 ,Experimental and Cognitive Psychology ,Curvature ,Article ,Perceptual organization ,configural processing ,050105 experimental psychology ,Visual processing ,03 medical and health sciences ,0302 clinical medicine ,Artificial Intelligence ,0501 psychology and cognitive sciences ,Computer vision ,perceptual organization ,Projection (set theory) ,Mathematics ,nonaccidental properties ,Visual search ,geons ,business.industry ,05 social sciences ,Cognitive neuroscience of visual object recognition ,Collinearity ,Sensory Systems ,Ophthalmology ,lcsh:Psychology ,Line (geometry) ,Artificial intelligence ,business ,030217 neurology & neurosurgery - Abstract
According to Recognition-By-Components theory, object recognition relies on a specific subset of three-dimensional shapes called geons. In particular, these configurations constitute a powerful cue to three-dimensional object reconstruction because their two-dimensional projection remains viewpoint-invariant. While a large body of literature has demonstrated sensitivity to changes in these so-called nonaccidental configurations, it remains unclear what information is used in establishing such sensitivity. In this study, we explored the possibility that nonaccidental configurations can already be inferred from the basic constituents of objects, namely, their edges. We constructed a set of stimuli composed of two lines corresponding to various nonaccidental properties and configurations underlying the distinction between geons, including collinearity, alignment, curvature of contours, curvature of configuration axis, expansion, cotermination, and junction type. Using a simple visual search paradigm, we demonstrated that participants were faster at detecting targets that differed from distractors in a nonaccidental property than in a metric property. We also found that only some but not all of the observed sensitivity could have resulted from simple low-level properties of our stimuli. Given that such sensitivity emerged from a configuration of only two lines, our results support the view that nonaccidental configurations could be encoded throughout the visual processing hierarchy even in the absence of object context. ispartof: i-Perception vol:8 issue:2 pages:1-12 ispartof: location:Leuven, Belgium status: published
- Published
- 2017
27. One-shot viewpoint invariance in matching novel objects
- Author
-
Moshe Bar and Irving Biederman
- Subjects
Adult ,Adolescent ,Rotation ,Computer science ,media_common.quotation_subject ,Shape representation ,Geons ,Viewpoint invariance ,Judgment ,Perception ,Reaction Time ,Humans ,Object perception ,Scaling ,media_common ,Depth Perception ,Communication ,One shot ,business.industry ,Pattern recognition ,Space perception ,Viewing angle ,Sensory Systems ,Form Perception ,Ophthalmology ,Nonaccidental properties ,Mental representation ,Artificial intelligence ,Shape recognition ,business ,Geon (physics) - Abstract
Humans often evidence little difficulty at recognizing objects from arbitrary orientations in depth. According to one class of theories, this competence is based on generalization from templates specified by metric properties (MPs), that were learned for the various orientations. An alternative class of theories assumes that non-accidental properties (NAPs) might be exploited so that even novel objects can be recognized under depth rotation. After scaling MP and NAP differences so that they were equally detectable when the objects were at the same orientation in depth, the present investigation assessed the effects of rotation on same-different judgments for matching novel objects. Judgments of a sequential pair of images of novel objects, when rendered from different viewpoints, revealed relatively low costs when the objects differed in a NAP of a single part, i.e. a geon. However, rotation dramatically reduced the detectability of MP differences to a level well below that expected by chance. NAPs offer a striking advantage over MPs for object classification and are therefore more likely to play a central role in the representation of objects.
- Published
- 1999
- Full Text
- View/download PDF
28. Urban green valuation integrating biophysical and qualitative aspects.
- Author
-
Lang S
- Abstract
Urban green mapping has become an operational task in city planning, urban land management, and quality of life assessments. As a multi-dimensional, integrative concept, urban green comprising several ecological, socio-economic, and policy-related aspects. In this paper, the author advances the representation of urban green by deriving scale-adapted, policy-relevant units. These so-called geons represent areas of uniform green valuation under certain size and homogeneity constraints in a spatially explicit representation. The study accompanies a regular monitoring scheme carried out by the urban municipality of the city of Salzburg, Austria, using optical satellite data. It was conducted in two stages, namely SBG_QB (10.2 km², QuickBird data from 2005) and SBG_WV (140 km², WorldView-2 data from 2010), within the functional urban area of Salzburg. The geon delineation was validated by several quantitative measures and spatial analysis techniques, as well as ground documentation, including panorama photographs and visual interpretation. The spatial association pattern was assessed by calculating Global Moran's I with incremental search distances. The final geonscape, consisting of 1083 units with an average size of 13.5 ha, was analyzed by spatial metrics. Finally, categories were derived for different types of functional geons. Future research paths and improvements to the described strategy are outlined., Competing Interests: No potential conflict of interest was reported by the author.
- Published
- 2017
- Full Text
- View/download PDF
29. Geoni - kandidati za ulogu početnih mikrocrnih rupa i njihova važnost u Planckovoj fizici
- Author
-
Klimets, Alexandr P.
- Subjects
gravitationally bound massless quanta ,geons ,microscopic black holes ,singularities of the general theory of relativity - Abstract
The article describes exotic objects, the geons, which emerge as the result of gravitational attraction among massless energy quanta. It is shown that the formation of geons occurs at the energy E_Pl = 10 19 GeV and leads to the rise of microscopic black holes of a Planck dimension, Planck mass and two horizon events. It is shown that the formation of Planck geons is energetically more likely in 3-dimensional space than with "physics" of geons in a space of a different number of dimensions, what, as it appears, determined the 4-dimensional space-time at the very first moments after the "Big Bang". The problem of singularity in the theory of relativity is discussed. It is shown that, from the mathematical point of view, any space of finite dimensions of any extension can be placed in a dimensionless "point" of space of the Planck dimensions without the change of density of matter of the Metagalaxy. That theoretically solves the problem of physical singularities of the general theory of relativity., Razmatra ju se eqzotični objekti, geoni, koji su posljedica gravitacijskog privlačenja među bezmasenim kvantima energije. Pokazuje se da se geoni javlja ju na energiji EPl = 1019 GeV, što vodi na stvaranje mikroskopskih crnih rupa Planckove veličine. Pokazuje se da je stvaranje Planckovih geona vjerojatnije u 3-dimenzijskom prostoru nego "fizika" geona u prostoru s drugim brojem dimenzija, što je, kako se čini, odredilo 4-dimenzijski prostor-vrijeme u prvi trenucima nakon "Velikog praska". Raspravlja se problem singularnosti u teoriji relativnosti. Pokazuje se, polazeći s matematičkog stajališta, da se bilo koji prostor konačne veličine može smjestiti u bezdimenzijski "točkast" prostor Planckove veličine bez promjene gustoće Metagalaksije. Ovo teorijski rješava problem fizičkih singularnosti opće teorije relativnosti.
- Published
- 2000
30. Sensitivity to Nonaccidental Configurations of Two-Line Stimuli.
- Author
-
Kubilius J, Sleurs C, and Wagemans J
- Abstract
According to Recognition-By-Components theory, object recognition relies on a specific subset of three-dimensional shapes called geons . In particular, these configurations constitute a powerful cue to three-dimensional object reconstruction because their two-dimensional projection remains viewpoint-invariant. While a large body of literature has demonstrated sensitivity to changes in these so-called nonaccidental configurations, it remains unclear what information is used in establishing such sensitivity. In this study, we explored the possibility that nonaccidental configurations can already be inferred from the basic constituents of objects, namely, their edges. We constructed a set of stimuli composed of two lines corresponding to various nonaccidental properties and configurations underlying the distinction between geons, including collinearity, alignment, curvature of contours, curvature of configuration axis, expansion, cotermination, and junction type. Using a simple visual search paradigm, we demonstrated that participants were faster at detecting targets that differed from distractors in a nonaccidental property than in a metric property. We also found that only some but not all of the observed sensitivity could have resulted from simple low-level properties of our stimuli. Given that such sensitivity emerged from a configuration of only two lines, our results support the view that nonaccidental configurations could be encoded throughout the visual processing hierarchy even in the absence of object context.
- Published
- 2017
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.