2 research outputs found
Using simulated Tianqin gravitational wave data and electromagnetic wave data to study the coincidence problem and Hubble tension problem
In this paper, we use electromagnetic wave data (H0LiCOW, , SNe) and
gravitational wave data (Tianqin) to constrain the interacting dark energy
(IDE) model and investigate the Hubble tension problem and coincidences
problem. By combining these four kinds of data (Tianqin+H0LiCOW+SNe+), we
obtained the parameter values at the confidence interval of :
, ,
, and . According
to our results, the best valve of show that the Hubble tension problem
can be alleviated to some extent. In addition, the of which the center value indicates the
coincidence problem is slightly alleviated. However, the is
still within the error range which indicates the CDM model
is still the model which is in best agreement with the observational data at
present. Finally, we compare the constraint results of electromagnetic wave and
gravitational wave on the model parameters and find that the constraint effect
of electromagnetic wave data on model parameters is better than that of
simulated Tianqin gravitational wave data.Comment: The article has been accepted by Chinese Physics
Testing the spatial geometry of the universe with TianQin: the prospect of using supermassive black hole binaries
The determination of the spatial geometry of the universe plays an important
role in modern cosmology. Any deviation from the cosmic curvature
would have a profound impact on the primordial inflation paradigm and
fundamental physics. In this paper, we carry out a systematic study of the
prospect of measuring cosmic curvature with the inspiral signal of supermassive
black hole binaries (SMBHBs) that could be detected with TianQin. The study is
based on a cosmological-model-independent method that extended the application
of gravitational wave (GW) standard sirens in cosmology. By comparing the
distances from future simulated GW events and simulated data, we
evaluate if TianQin would produce robust constraints on the cosmic curvature
parameter . More specifically, we consider 3-yr to 10-yr
observations of supermassive black hole binaries with total masses ranging from
to . Our results show that in the future, with
the synergy of 10-yr high-quality observations, we can tightly constrain the
curvature parameter at the level of .
Moreover, our findings indicate that the total mass of SMBHB does influence the
estimation of cosmic curvature, implied by the analysis performed on different
subsamples of gravitational wave data. Therefore, TianQin is expected to
provide a powerful and competitive probe of the spatial geometry of the
universe, compared to future spaced-based detectors such as DECIGO.Comment: This article has been accepted by Astronomy & Astrophysic