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A Tale of Two Distances

Martin Kunz·Bruce A. Bassett
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Abstract

There are two basic ways to measure physical distances in cosmology: One based on standard candles and one based on standard rulers. Comparing current data for each method allows us to rule out axion-photon mixing and dust-extinction as the sources of supernova dimming and generally protects the case for cosmic acceleration from attacks based on loss of photons. The combined data constrains the energy densities in a LCDM model to 0.19 < Omega_m < 0.32 and 0.47 < Omega_Lambda < 0.82 (at 2σ) without recourse to any further data sets. Future data will improve on these limits and allow us to place constraints on more exotic physics.

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Martin Kunz, Bruce A. Bassett. 2004-06-01. A Tale of Two Distances. https://arxiv.org/abs/astro-ph/0406013

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