BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS
For decades, H [subscript 0] and q [subscript 0] were the quest of cosmology, as they promised to characterize our "world model" without reference to a specific cosmological framework. Using Monte Carlo simulations, we show that q [subscript 0] cannot be directly measured using distance in...
| Main Authors: | , |
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| Format: | Article |
| Language: | en_US |
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IOP Publishing
2015
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| Online Access: | http://hdl.handle.net/1721.1/94538 https://orcid.org/0000-0001-7776-7240 |
| _version_ | 1826217637026201600 |
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| author | Turner, Michael S. Neben, Abraham Richard |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Turner, Michael S. Neben, Abraham Richard |
| author_sort | Turner, Michael S. |
| collection | MIT |
| description | For decades, H [subscript 0] and q [subscript 0] were the quest of cosmology, as they promised to characterize our "world model" without reference to a specific cosmological framework. Using Monte Carlo simulations, we show that q [subscript 0] cannot be directly measured using distance indicators with both accuracy (without offset away from its true value) and precision (small error bar). While H [subscript 0] can be measured with accuracy and precision, to avoid a small bias in its direct measurement (of order 5%) we demonstrate that the pair H [subscript 0] and Ω [subscript M] (assuming flatness and w = –1) is a better choice of two parameters, even if our world model is not precisely ΛCDM. We illustrate this with analysis of the Constitution set of supernovae and indirectly infer q [subscript 0] = –0.57 ± –0.04. Finally, we show that it may be possible to directly determine q [subscript 0] with both accuracy and precision using the time dependence of redshifts ("redshift drift"). |
| first_indexed | 2024-09-23T17:06:31Z |
| format | Article |
| id | mit-1721.1/94538 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T17:06:31Z |
| publishDate | 2015 |
| publisher | IOP Publishing |
| record_format | dspace |
| spelling | mit-1721.1/945382022-09-29T23:43:32Z BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS Turner, Michael S. Neben, Abraham Richard Massachusetts Institute of Technology. Department of Physics MIT Kavli Institute for Astrophysics and Space Research Neben, Abraham Richard For decades, H [subscript 0] and q [subscript 0] were the quest of cosmology, as they promised to characterize our "world model" without reference to a specific cosmological framework. Using Monte Carlo simulations, we show that q [subscript 0] cannot be directly measured using distance indicators with both accuracy (without offset away from its true value) and precision (small error bar). While H [subscript 0] can be measured with accuracy and precision, to avoid a small bias in its direct measurement (of order 5%) we demonstrate that the pair H [subscript 0] and Ω [subscript M] (assuming flatness and w = –1) is a better choice of two parameters, even if our world model is not precisely ΛCDM. We illustrate this with analysis of the Constitution set of supernovae and indirectly infer q [subscript 0] = –0.57 ± –0.04. Finally, we show that it may be possible to directly determine q [subscript 0] with both accuracy and precision using the time dependence of redshifts ("redshift drift"). National Science Foundation (U.S.) United States. Dept. of Energy MIT Bruno Rossi Graduate Fellowship in Astrophysics 2015-02-17T13:31:32Z 2015-02-17T13:31:32Z 2013-05 2012-09 Article http://purl.org/eprint/type/JournalArticle 0004-637X 1538-4357 http://hdl.handle.net/1721.1/94538 Neben, Abraham R., and Michael S. Turner. “BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS.” The Astrophysical Journal 769, no. 2 (May 14, 2013): 133. © 2013 The American Astronomical Society https://orcid.org/0000-0001-7776-7240 en_US http://dx.doi.org/10.1088/0004-637x/769/2/133 The Astrophysical Journal Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf IOP Publishing American Astronomical Society |
| spellingShingle | Turner, Michael S. Neben, Abraham Richard BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS |
| title | BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS |
| title_full | BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS |
| title_fullStr | BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS |
| title_full_unstemmed | BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS |
| title_short | BEYOND H[subscript 0] AND q[subscript 0]: COSMOLOGY IS NO LONGER JUST TWO NUMBERS |
| title_sort | beyond h subscript 0 and q subscript 0 cosmology is no longer just two numbers |
| url | http://hdl.handle.net/1721.1/94538 https://orcid.org/0000-0001-7776-7240 |
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