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Updated: May 26, 2026

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Observational constraints on loop quantum cosmology
Martin Bojowald1, Gianluca Calcagni, Shinji Tsujikawa
1Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, 16802, USA.
Abstract:
In the inflationary scenario of loop quantum cosmology in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to compare with observations. Since inverse-volume corrections can provide strong contributions to the running spectral indices, inclusion of terms higher than the second-order runnings in the power spectra is crucially important. Using the recent data of cosmic microwave background and other cosmological experiments, we place bounds on the quantum corrections.
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