In a new study published in Physical Review Letters, scientists have estimated a new lower bound on the mass of ...

Because mass is a property of matter, the "stuff" of the universe affected by gravity, nuclear reactions still conserve the overall mass–energy of systems. Indeed, only in nuclear physics ...

Dark matter makes up a large portion of the universe, but we've never seen it. Here's what we know, what it might be, and why it could change everything. More than 80% of the universe's matter is ...

Everything we visualize about space, including stars, planets, gases, and even galaxies, make up just a small fraction of the ...