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تسجيل مستخدم جديدThe power spectra of CMB and density fluctuations seeded by local cosmic strings
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We compute the power spectra in the cosmic microwave background and cold dark matter (CDM) fluctuations seeded by strings, using the largest string simulations performed so far to evaluate the two-point functions of their stress energy tensor. We find that local strings differ from global defects in that the scalar components of the stress-energy tensor dominate over vector and tensor components. This result has far reaching consequences. We find that cosmic strings exhibit a single Doppler peak of acceptable height at high $ell$. They also seem to have a less severe bias problem than global defects, although the CDM power spectrum in the ``standard cosmology (flat geometry, zero cosmological constant, 5% baryonic component) is the wrong shape to fit large scale structure data.
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