According to the theory of gravitation, every particle of matter in the universe attracts every other particle with a force that increases as either the mass of the particles increases, or their proximity to one another increases, or both.
(Written summary below video)
Topic
Neutrinos and the Dark Matter mystery
Frameworks
Problem / Solution Answer a Question
Main Point
Question / Problem The observable matter in the universe only adds up to about 10% of the mass that would be needed for gravity to account for the observable structures in the universe. So given that we believe in gravity, and we believe we're correctly observing structures, where is the other 90% of the universe's mass?
Answer / Solution Neutrinos seem to account for about 20% of it, but more broadly the discovery that a tiny particle's crazy small mass might still add up to something significant (because of how numerous that type of particle is) is making scientists think that maybe the tiny masses of elementary particles is a big part of the missing mass.
Summary
P1 - Background on gravity, introduction to Curious Problem
After briefly summarizing what gravity means, this paragraph establishes the 90% missing matter conundrum, and says that cosmologists have postulated something called 'dark matter', which seems to just be a placeholder name.
P2 - A potential Solution that seemed non-viable
This paragraph introduces neutrinos as one possible answer/solution that cosmologists had considered, but ultimately rejected since they assumed that neutrinos had no mass.
P3 - New research brings back hope to possible Solution
This paragraph presents new research that suggests that neutrinos do have mass, so they're back as a contender for this dark matter problem we're trying to solve.
P5 - Implications of New research
The author's take on where we're at usually comes in the final paragraph of Science passages. Here, it sounds like neutrinos are promising as a Partial Solution, and they're also opening up new lines of inquiry that are potentially an encouraging step forward in the process of trying to find the Whole Solution.
Topic
The search for "dark matter" and the possible role of neutrinos in accounting for missing mass in the universe.