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When researchers invoke the term ‘last billion’ to refer to emerging ICT users, they often focus on network access as a ‘solution’ while neglecting important considerations such as local ownership or knowledge, both of which are essential to sustainable and empowering uses of these technologies in developing contexts. Research reveals that mere access to networks without active community involvement can fail to empower already marginalized and disenfranchized users. Building upon these findings, this article uses ethnographic methods to explore the meanings of ‘network sovereignty’ in rural, low-income communities in developing countries. It presents two case studies focused on local network initiatives in Oaxaca, Mexico and Bunda, Tanzania and then offers an assessment matrix to support future network sovereignty research based on five categories: community engagement; local cultures/ontologies; digital education and technological knowledge; economic ownership; and community empowerment. Our comparative research reveals that communities that are able to assert collective ownership over local infrastructure, embed network initiatives within local cultures, and prioritize digital education are much more likely to create and sustain local networks that support their economic, political, and cultural lives.

Abstract Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo’s third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours–months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain uppermore »limits do not surpass indirect energy constraints for any of these targets.« less