Mass causes gravity. That’s why everything in the Solar System revolves around the Sun as it’s the most massive thing around. However, a new study posits that gravity can exist without mass, turning both our understanding of Newtonian physics on its head and raising new questions about the existence of dark matter.
Category
📚
LearningTranscript
00:00Mass causes gravity, that's why everything in the solar system revolves around the sun,
00:08as it's the most massive thing around.
00:10However, a new study posits that gravity can exist without mass, which turns both our understanding
00:15of Newtonian physics on its head and raises new questions about the existence of dark
00:19matter.
00:20Experts believe that dark matter likely makes up some 85% of the universe, but we have never
00:25observed it, meaning it is basically the only thing we can come up with to account for our
00:29all of the extra gravity holding galaxies together.
00:32However, a new theory from astrophysicist Richard Liu suggests that instead of dark
00:36matter, topological defects in the universe might increase gravitational connectedness
00:41without the associated mass.
00:43Liu was initially attempting to solve a version of Weinstein's field equations, saying he
00:47was driven by his frustration with the status quo, namely the notion of dark matter's existence,
00:52despite the lack of any direct evidence for a whole century, saying instead his calculations
00:57revealed shell-shaped topological defects that manifest in particular areas of space
01:02with extremely dense amounts of matter.
01:04These shells contain positive mass inside a layer of negative mass, cancelling one another
01:09out.
01:10However, when a massive object like a star rests atop it, it gets dragged inward.
01:13Liu says it may not be a smoking gun for the death of dark matter, but adds it's the first
01:18solution with mathematical proof that gravity can exist without mass.