{"paper":{"title":"Ringing the initial Universe: the response of overdensity and transformed-density power spectra to initial spikes","arxiv_id":"1305.1629","primary_cat":"astro-ph.CO","submitted_at":"2013-05-07T20:00:08+00:00","version_compiled":"v2"},"notice":"Every quoted sentence is the authors' text from the arXiv listing abstract. Labels and probabilities are the outputs of classifier-1.13-20260917 on the question bank abstract-p1-20260923, exactly as returned. No sentence in this record was written by a language model.","schema":"pith.compiled-record/v0","status":"compiled","abstract":{"source":"arXiv listing abstract v2","sentences":[{"i":0,"p":0.6,"id":"s0","own":true,"role":"method","text":"We present an experiment in which we 'ring' a set of cosmological N-body-simulation initial conditions, placing spikes in the initial power spectrum at different wavenumber bins.","hedge":{"p":0.98,"label":"asserted"},"own_p":0.96,"main_claim_p":0.04,"quantitative":false,"quantitative_p":0.08,"role_probabilities":{"gap":0.0,"method":0.6,"result":0.0,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.4,"interpretation":0.0}},{"i":1,"p":0.93,"id":"s1","own":true,"role":"method","text":"We then measure where these spikes end up in the final conditions.","hedge":{"p":0.98,"label":"asserted"},"own_p":0.97,"main_claim_p":0.03,"quantitative":false,"quantitative_p":0.03,"role_probabilities":{"gap":0.0,"method":0.93,"result":0.0,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.07,"interpretation":0.0}},{"i":2,"p":1.0,"id":"s2","own":true,"role":"result","text":"In the usual overdensity power spectrum, most sensitive to contracting and collapsing dense regions, initial power on slightly non-linear scales (k ~ 0.3 h/Mpc) smears to smaller scales, coming to dominate the initial power once there.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.92,"main_claim_p":0.22,"quantitative":true,"quantitative_p":0.93,"role_probabilities":{"gap":0.0,"method":0.0,"result":1.0,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.0}},{"i":3,"p":1.0,"id":"s3","own":true,"role":"result","text":"Log-density and Gaussianized-density power spectra, sensitive to low-density (expanding) and high-density regions, respond differently: initial spikes spread symmetrically in scale, both upward and downward.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.93,"main_claim_p":0.25,"quantitative":false,"quantitative_p":0.38,"role_probabilities":{"gap":0.0,"method":0.0,"result":1.0,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.0}},{"i":4,"p":0.94,"id":"s4","own":true,"role":"result","text":"In fact, in the power spectrum of 1/(1 + {\\delta}), spikes migrate to larger scales, showing the magnifying effect of voids on small-scale modes.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.91,"main_claim_p":0.1,"quantitative":false,"quantitative_p":0.34,"role_probabilities":{"gap":0.0,"method":0.0,"result":0.94,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.06}},{"i":5,"p":0.86,"id":"s5","own":true,"role":"result","text":"These power spectra show much greater sensitivity to small-scale initial features.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.88,"main_claim_p":0.17,"quantitative":true,"quantitative_p":0.61,"role_probabilities":{"gap":0.0,"method":0.0,"result":0.86,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.14}},{"i":6,"p":0.7,"id":"s6","own":true,"role":"contribution","text":"We also test the difference between an approximation of the Ly-{\\alpha} flux field, and its Gaussianized form, and give a toy model that qualitatively explains the symmetric power spreading in Gaussianized-density power spectra.","hedge":{"p":0.94,"label":"asserted"},"own_p":0.94,"main_claim_p":0.06,"quantitative":false,"quantitative_p":0.37,"role_probabilities":{"gap":0.0,"method":0.23,"result":0.05,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.7,"interpretation":0.02}},{"i":7,"p":0.72,"id":"s7","own":true,"role":"contribution","text":"Also, we discuss how to use this framework to estimate power-spectrum covariance matrices.","hedge":{"p":0.79,"label":"asserted"},"own_p":0.8,"main_claim_p":0.03,"quantitative":false,"quantitative_p":0.04,"role_probabilities":{"gap":0.0,"method":0.07,"result":0.0,"background":0.0,"limitation":0.0,"future_work":0.21,"contribution":0.72,"interpretation":0.0}},{"i":8,"p":0.97,"id":"s8","own":false,"role":"interpretation","text":"This can be used to track the fate of information in the Universe, that takes the form of initial degrees of freedom, one random spike per initial mode.","hedge":{"p":0.76,"label":"asserted"},"own_p":0.45,"main_claim_p":0.18,"quantitative":true,"quantitative_p":0.5,"role_probabilities":{"gap":0.0,"method":0.0,"result":0.0,"background":0.0,"limitation":0.0,"future_work":0.02,"contribution":0.01,"interpretation":0.97}}]},"compiled":{"main_claim":{"p":0.46,"text":"These power spectra show much greater sensitivity to small-scale initial features.","location":"abstract 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