https://hackerpaper.kaipfister.de/p/1706.07870/Collected HN comments and submissions linking this paper.enMon, 02 Nov 2026 11:16:22 GMThttps://news.ycombinator.com/item?id=23792944urn:hackerpapers:mention:1706.07870:23792944Fri, 10 Jul 2020 16:06:43 GMT<p>Crucially we can show it&#x27;s there by examining how it affects the light from bright background sources passing through it: there is a spectral shift without the imposition of new emission or absorption lines, and there is Einstein lensing [ https://en.wikipedia.org/wiki/Gravitational_lens ]. We can see this in the large by observing the http://www.astro.ucla.edu/~wright/Lyman-alpha-forest.html on lines of sight through and near galaxy clusters. For example, [presentation abstract] https://depts.washington.edu/astron/event/tba-liang-dai/ [related paper https://arxiv.org/abs/1804.03149v2 ] or…</p><p><a href="https://hackerpaper.kaipfister.de/p/1706.07870/">Paper and discussion history</a>. A mention is not an endorsement.</p>astro-ph.CO