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We introduce a systematic method to derive the effective action for domain walls directly from the scalar field theory that gives rise to their solitonic solutions. The effective action for the Goldstone mode, which characterizes the soliton’s position, is shown to consist of the Nambu-Goto action supplemented by higher-order curvature invariants associated to its worldvolume metric. Our approach constrains the corrections to a finite set of Galileon terms, specifying both their functional forms and the procedure to compute their coefficients. We do a collection of tests across various models in 2 +1 and 3 +1 dimensions that confirm the validity of this framework. Additionally, the method is extended to include bound scalar fields living on the world sheet, along with their couplings to the Goldstone mode. These interactions reveal a universal nonminimal coupling of these scalar fields to the Ricci scalar on the world sheet. A significant consequence of this coupling is the emergence of a parametric instability, driven by interactions between the bound states and the Goldstone mode. 

This file contains data tables representing gravitational wave backgrounds (GWBs) produced by Nambu-Goto cosmic strings evolved under numerical gravitational backreaction. The GWBs were produced using the methodology of "More accurate gravitational wave backgrounds from cosmic strings" [to appear], by the same authors as this dataset. The file is organized in three columns: The base-10 logarithm of the string coupling to gravity, G\mu. The range is from -8 to -22 in steps of -0.1. The frequency in Hz, f. The range is from 10^(-12) Hz to 10^5 Hz in multiplicative steps of 10^(0.02). The critical energy density fraction in gravitational waves scaled by the dimensionless Hubble constant squared, \Omega_{gw} h^2. 

This file contains a data table representing the average power spectrum, P_n, of Nambu-Goto cosmic strings evolved under numerical gravitational backreaction. The power spectra and the methods used to produce them are reported on in "Numerical gravitational backreaction on cosmic string loops from simulation" [to appear], by the same authors as this dataset. See Fig. 5 of that paper for a visualization. The file is organized in three columns: The fraction of evaporation, chi. The range is from 0.0 to 0.7 in steps of 0.1. The mode number, n. The range is from 2^0 to 2^39 in multiplicative steps of 2. The logarithmically binned elements of the power spectrum, nP_n. Bin edges are 2^i to 2^(i+1)-1 for i from 0 to 39. 

Abstract We perform a detailed comparison of the dynamics of cosmic stringloops obtained in cosmological field theory simulations with their expected motion according to theNambu-Goto action. We demonstrate that these loops follow thetrajectories predicted within the NG effective theory except in regionsof high curvature where energy is emitted from the loop in the form of massiveradiation. This energy loss continues for all the loopsstudied in this simulation until they self-intersect or become small enough that they annihilateand disappear well before they complete a single oscillation. We comment on the relevance of thisinvestigation to the interpretation of the results from cosmological field theory simulationsas well as their extrapolation to a cosmological context.