### Abstract

The redshift drift of objects moving in the Hubble flow has been proposed as a powerful model-independent probe of the underlying cosmology. A measurement of the first- and second-order redshift derivatives appears to be well within the reach of upcoming surveys using as the Extremely Large Telescope high resolution spectrometer (ELT-HIRES) and the Square Kilometer Phase 2 Array (SKA). Here we show that an unambiguous prediction of the R_{h} = ct cosmology is zero drift at all redshifts, contrasting sharply with all other models in which the expansion rate is variable. For example, multiyear monitoring of sources at redshift z = 5 with the ELT-HIRES is expected to show a velocity shift Δv = -15 cm s^{-1} yr^{-1} due to the redshift drift in Planck ΛCDM, while Δv = 0 cm s^{-1} yr^{-1} in R_{h} = ct. With an anticipated ELT-HIRES measurement error of ±5 cm s^{-1} yr^{-1} after 5 yr, these upcoming redshift drift measurements might therefore be able to differentiate between R_{h} = ct and Planck ΛCDM at ~3σ, assuming that any possible source evolution is well understood. Such a result would provide the strongest evidence yet in favour of the R_{h} = ct cosmology. With a 20-yr baseline, these observations could favour one of these models over the other at better than 5σ.

Original language | English (US) |
---|---|

Pages (from-to) | L61-L63 |

Journal | Monthly Notices of the Royal Astronomical Society: Letters |

Volume | 463 |

Issue number | 1 |

DOIs | |

State | Published - Nov 21 2016 |

### Fingerprint

### Keywords

- Cosmological parameters
- Cosmology: observations
- Cosmology: theory
- Distance scale

### ASJC Scopus subject areas

- Astronomy and Astrophysics
- Space and Planetary Science

### Cite this

**Definitive test of the R _{h} = ct universe using redshift drift.** / Melia, Fulvio.

Research output: Contribution to journal › Article

_{h}= ct universe using redshift drift',

*Monthly Notices of the Royal Astronomical Society: Letters*, vol. 463, no. 1, pp. L61-L63. https://doi.org/10.1093/mnrasl/slw157

}

TY - JOUR

T1 - Definitive test of the Rh = ct universe using redshift drift

AU - Melia, Fulvio

PY - 2016/11/21

Y1 - 2016/11/21

N2 - The redshift drift of objects moving in the Hubble flow has been proposed as a powerful model-independent probe of the underlying cosmology. A measurement of the first- and second-order redshift derivatives appears to be well within the reach of upcoming surveys using as the Extremely Large Telescope high resolution spectrometer (ELT-HIRES) and the Square Kilometer Phase 2 Array (SKA). Here we show that an unambiguous prediction of the Rh = ct cosmology is zero drift at all redshifts, contrasting sharply with all other models in which the expansion rate is variable. For example, multiyear monitoring of sources at redshift z = 5 with the ELT-HIRES is expected to show a velocity shift Δv = -15 cm s-1 yr-1 due to the redshift drift in Planck ΛCDM, while Δv = 0 cm s-1 yr-1 in Rh = ct. With an anticipated ELT-HIRES measurement error of ±5 cm s-1 yr-1 after 5 yr, these upcoming redshift drift measurements might therefore be able to differentiate between Rh = ct and Planck ΛCDM at ~3σ, assuming that any possible source evolution is well understood. Such a result would provide the strongest evidence yet in favour of the Rh = ct cosmology. With a 20-yr baseline, these observations could favour one of these models over the other at better than 5σ.

AB - The redshift drift of objects moving in the Hubble flow has been proposed as a powerful model-independent probe of the underlying cosmology. A measurement of the first- and second-order redshift derivatives appears to be well within the reach of upcoming surveys using as the Extremely Large Telescope high resolution spectrometer (ELT-HIRES) and the Square Kilometer Phase 2 Array (SKA). Here we show that an unambiguous prediction of the Rh = ct cosmology is zero drift at all redshifts, contrasting sharply with all other models in which the expansion rate is variable. For example, multiyear monitoring of sources at redshift z = 5 with the ELT-HIRES is expected to show a velocity shift Δv = -15 cm s-1 yr-1 due to the redshift drift in Planck ΛCDM, while Δv = 0 cm s-1 yr-1 in Rh = ct. With an anticipated ELT-HIRES measurement error of ±5 cm s-1 yr-1 after 5 yr, these upcoming redshift drift measurements might therefore be able to differentiate between Rh = ct and Planck ΛCDM at ~3σ, assuming that any possible source evolution is well understood. Such a result would provide the strongest evidence yet in favour of the Rh = ct cosmology. With a 20-yr baseline, these observations could favour one of these models over the other at better than 5σ.

KW - Cosmological parameters

KW - Cosmology: observations

KW - Cosmology: theory

KW - Distance scale

UR - http://www.scopus.com/inward/record.url?scp=84994525215&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84994525215&partnerID=8YFLogxK

U2 - 10.1093/mnrasl/slw157

DO - 10.1093/mnrasl/slw157

M3 - Article

AN - SCOPUS:84994525215

VL - 463

SP - L61-L63

JO - Monthly Notices of the Royal Astronomical Society: Letters

JF - Monthly Notices of the Royal Astronomical Society: Letters

SN - 1745-3933

IS - 1

ER -