Constraining the dark matter-vacuum energy interaction using the EDGES 21-cm absorption signal

The recent measurement of the global 21-cm absorption signal reported by the Experiment to Detect the Global Epoch of Reionization Signature (EDGES) Collaboration is in tension with the prediction of the $\Lambda$CDM model at a $3.8\,\sigma$ significance level. In this work, we report that this tension can be released by introducing an interaction between dark matter and vacuum energy. We perform a model parameter estimation using a combined dataset including EDGES and other recent cosmological observations, and find that the EDGES measurement can marginally improve the constraint on parameters that quantify the interacting vacuum, and that the combined dataset favours the $\Lambda$CDM at 68\% CL. This proof-of-the-concept study demonstrates the potential power of future 21-cm experiments to constrain the interacting dark energy models.Comment: 6 pages, 5 figures, 1 table; accepted for publication in Ap

A measurement of the Hubble constant using galaxy redshift surveys

We perform a measurement of the Hubble constant, $H_0$, using the latest baryonic acoustic oscillations (BAO) measurements from galaxy surveys of 6dFGS, SDSS DR7 Main Galaxy Sample, BOSS DR12 sample, and eBOSS DR14 quasar sample, in the framework of a flat $\Lambda$CDM model. Based on the Kullback-Leibler (KL) divergence, we examine the consistency of $H_0$ values derived from various data sets. We find that our measurement is consistent with that derived from Planck and with the local measurement of $H_0$ using the Cepheids and type Ia supernovae. We perform forecasts on $H_0$ from future BAO measurements, and find that the uncertainty of $H_0$ determined by future BAO data alone, including complete eBOSS, DESI and Euclid-like, is comparable with that from local measurements.Comment: 5 pages, 2 figures, 2 tables; accepted for publication in Ap

Being Chinese Muslims in Dubai: religion and nationalism in a transnational space

Chinese Muslims, or the Hui people, an ethno-religious minority that straddles two civilisations, have drawn much attention from the media and academia as China strengthens its ties with Muslim-majority countries in the last two decades. Possessing unique cultural capital, Chinese Muslims are often seen as the ‘good’ Muslims of China, distinguished from the Turkic-speaking Uyghurs who are suspected of separatist motives and inclination towards religious extremism. However, the Chinese government’s intensifying campaign to curb ‘Islamisation’ and promote further Sinicisation of Chinese Muslims in the last few years has caused much concern. This paper considers the social forces that produce and sustain the transnational Chinese Muslim community in Dubai, a strategic location on the map of China’s Belt and Road Initiative. It examines the experiences of Chinese Muslims in Dubai’s dynamic and transient urban space and seeks to understand their complex emotions towards China. It suggests that the social context of Dubai may be inducive to the reinforcement of ‘Chinese Muslim’ identity due to the UAE’s policies on foreign populations and attitudes towards cultural diversity, the increasing influence of the Chinese state apparatus among overseas Chinese communities, as well as heightened patriotism and nationalism as the result of China’s rise