Coherence Theory Solution to the Pinhole Camera

Abstract The Kerr-Schild double copy is a map between exact solutions of general relativity and Maxwell’s theory, where the nonlinear nature of general relativity is circumvented by considering solutions in the Kerr-Schild form. In this paper, we give a general formulation, where no simplifying assumption about the background metric is made, and show that the gauge theory source is affected by a curvature term that characterizes the deviation of the background spacetime from a constant curvature spacetime. We demonstrate this effect explicitly by studying gravitational solutions with non-zero cosmological constant. We show that, when the background is flat, the constant charge density filling all space in the gauge theory that has been observed in previous works is a consequence of this curvature term. As an example of a solution with a curved background, we study the Lifshitz black hole with two different matter couplings. The curvature of the background, i.e., the Lifshitz spacetime, again yields a constant charge density; however, unlike the previous examples, it is canceled by the contribution from the matter fields. For one of the matter couplings, there remains no additional non-localized source term, providing an example for a non-vacuum gravity solution corresponding to a vacuum gauge theory solution in arbitrary dimensions.

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The General Pinhole Camera: Effective and Efficient Nonuniform Sampling for Visualization

IEEE Transactions on Visualization and Computer Graphics ◽

10.1109/tvcg.2010.22 ◽

2010 ◽

Vol 16 (5) ◽

pp. 777-790 ◽

Cited By ~ 4

Author(s):

Voicu Popescu ◽

Paul Rosen ◽

Laura Arns ◽

Xavier Tricoche ◽

Chris Wyman ◽

...

Keyword(s):

Nonuniform Sampling ◽

Pinhole Camera

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Local loads on a toroidal shell

The Journal of Strain Analysis for Engineering Design ◽

10.1243/03093247v272059 ◽

1992 ◽

Vol 27 (2) ◽

pp. 59-66 ◽

Cited By ~ 3

Author(s):

D Redekop ◽

F Zhang

Keyword(s):

Cylindrical Shell ◽

Shell Theory ◽

Elastic Shell ◽

Toroidal Shell ◽

Pipe Bend ◽

Local Loads ◽

Simply Supported ◽

Linear Elastic ◽

Wide Range ◽

Theory Solution

In this study the effect of local loads applied on a sectorial toroidal shell (pipe bend) is considered. A linear elastic shell theory solution for local loads is first outlined. The solution corresponds to the case of a shell simply supported at the two ends. Detailed displacement and stress results are then given for a specific shell with loadings centred at three positions; the crown circles, the extrados, and the intrados. These results are compared with results for a corresponding cylindrical shell. The paper concludes with a table summarizing results for characteristic displacements and stresses in a number of shells, covering a wide range of geometric parameters.

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Development of a new pinhole camera for imaging in high dose-rate environments

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2017.10.082 ◽

2018 ◽

Vol 912 ◽

pp. 115-118 ◽

Cited By ~ 2

Author(s):

Koki Sueoka ◽

Jun Kataoka ◽

Miho Takabe ◽

Yasuhiro Iwamoto ◽

Makoto Arimoto ◽

...

Keyword(s):

Dose Rate ◽

High Dose Rate ◽

Pinhole Camera ◽

High Dose

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Simulating diffraction limiting in a pinhole camera

The Imaging Science Journal ◽

10.1179/174313109x442498 ◽

2009 ◽

Vol 57 (3) ◽

pp. 162-166

Author(s):

I Stephenson

Keyword(s):

Pinhole Camera

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Error Estimation for Known Marker Position Retrieval by Ideal Pinhole Camera Direct Observation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.841.192 ◽

2016 ◽

Vol 841 ◽

pp. 192-197

Author(s):

Constantin Radu Mirescu ◽

Gabriela Roșca

Keyword(s):

Gait Analysis ◽

Error Estimation ◽

Motion Capture ◽

Direct Observation ◽

Focal Point ◽

Pinhole Camera ◽

Point Of View ◽

Direct Approach ◽

Marker Position

For Motion Capture in Gait Analysis using Known Spherical Markers one simple direct approach is to compute the projection of the Marker Center using its projection in the Pixel Plane and based on it to find the location of the Marker on the line that connects the Marker Center Projection and the camera Focal Point. For various positions of the Marker in the workspace the exact image of the marker is computed using a genuine approach and compute back the approximation of the position based on the generated image. Various algorithms are taken in consideration and finally the results are assessed from the point of view of Gait Analysis and two directions for calculus improvement are identified.

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