Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 4 of 4 for “"bispectra"”.
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The Phase of the Cosmological Wavefunction
… the thesis classifies all parity-even graviton bispectra from local interactions to all orders in derivatives. We identify a minimal set of operators contributing to tree-level bispectra and show how diffeomorphism invariance links contact and exchange terms. Despite the complexity of bulk …
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Causality and unitarity in the early universe
… symmetries. It explores two-point functions, and bispectra in Minkowski and de Sitter spacetimes, and the matching to a concrete UV model. Chapter 7 analyses electromagnetism in a dielec- tric as an open system, highlighting gauge symmetry and the role of dissipation in current and noise …
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Robust Estimation Techniques for the Cosmological Analysis of Large Scale Structure
… present an efficient code to compute projected bispectra. The separation approach is orders of magnitude more efficient than the direct integration. This allows us to investigate the relation between biases in the estimated parameters and inaccurate modelling of non-linear redshift-space …
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Parameter Identification of Nonlinear Systems Using Perturbation Methods and Higher-Order Statistics
A parametric identification procedure is proposed that combines the method of multiple scales and higher-order statistics to efficiently and accurately model nonlinear systems. A theoretical background for the method of multiple scales and higher-order statistics is given. Validation of the …