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arXiv · 2608.28765

Comment on `Measuring the Hubble Constant Using Strongly Lensed Gravitational Wave Signals'

Jason S. C. Poon·Otto A. Hannuksela
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Abstract

In Huang et al (JCAP08(2023)003), the work claimed that the Hubble constant can be constrained from lensed gravitational waves, despite the absence of information on GW source redshift or Einstein radius (angular size of the lens), as long as lens redshift is provided independently. To demonstrate, the authors set up a singular isothermal sphere lens model and applied Fisher information matrix and Bayesian parameter estimation on injected lensed GWs. However, their conclusion contradicts our previous work on degeneracies of GW lens system parameters. In this comment, we illustrate that Hubble constant cannot be measured with lens redshift alone, in the absence of source redshift or (Einstein radius).

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Jason S. C. Poon, Otto A. Hannuksela. 2026-08-28. Comment on `Measuring the Hubble Constant Using Strongly Lensed Gravitational Wave Signals'. https://arxiv.org/abs/2608.28765

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