Search Results

Is gravity weaker over distances of billions of light-years?

Despite no experimental evidence showing that gravitons exist, they remain a respectable concept in the world of professional physicists.

For generations, physicists have been searching for a quantum theory of gravity. But what if gravity isn’t actually quantum at all?

Thanks to observations of gravitational waves, scientists were able to settle a longstanding debate over the speed of gravity.

Beyond stars, galaxies, and gravity, studying the fundamental workings of nature reveals widely applicable lessons for learners everywhere.

It’s not only the gravity from galaxies in a cluster that reveals dark matter, but the ejected, intracluster stars actually trace it out.

Electromagnetism, both nuclear forces, and even the Higgs force are mediated by known bosons. What about gravity? Does it require gravitons?

Humans, when we consider space travel, recognize the need for gravity. Without our planet, is artificial or antigravity even possible?

For centuries, Newton’s inverse square law of gravity worked beautifully, but no one knew why. Here’s how Einstein finally explained it.

Isaac Newton and Albert Einstein are locked in an eternal battle over the nature of gravity. Whose side are you on?

Einstein’s general relativity has reigned supreme as our theory of gravity for over a century. Could we reduce it back down to Newton’s law?

There are many theories of gravity out there, and many interpretations of wide binary star data. What have we really learned from it all?

In theory, dark matter is cold, collisionless, and only interacts via gravity. What we see in ultra-diffuse galaxies indicates otherwise.

All the stars, stellar corpses, planets, and other large, massive objects take on spherical or spheroidal shapes. Why is that universal?

Physicists recently created Coordinated Lunar Time, a time zone for our Moon.

DESI has allowed astronomers to create an unprecedented 3D map of the Universe representing 20% of the entire sky.

Forensics has reached the final frontier, and could be used to solve future space accidents—or crimes.

Time is relative, not absolute, as gravity and motion both cause time to dilate. Your head and feet, therefore, don’t age at the same rate.

Here on Earth, we commonly use terms like weight (in pounds) and mass (in kilograms) as though they’re interchangeable. They’re not.

The standard picture of our Universe is that it’s dominated by dark matter and dark energy. But this alternative is also worth considering.

How are we to deal with the quantization of spacetime and gravity?

Roger Babson wanted a “partial insulator, reflector, or absorber of gravity” — something, anything, that would stop or dampen it.

Matt Strassler’s journey into fundamental physics culminates in a brilliant explanation of the Higgs field. Enjoy this exclusive interview.

Gravity defies quantum mechanics. What does that mean for a theory of everything?

This measurement is crucial to confirm that one of the assumptions of Einstein’s theory of gravity is valid.

There are limits to where physics makes meaningful predictions: beyond the Planck length, time, or energy. Here’s why we can’t go further.

“We are all in orbit around the center of the Milky Way galaxy. How big is this collection of stars? Somewhere between 200 and 400 billion suns in the Milky Way galaxy, about 100,000 light years across.”

Newton thought that gravitation would happen instantly, propagating at infinite speeds. Einstein showed otherwise; gravity isn’t instant.

Here in our Universe, both normal and dark matter can be measured astrophysically. But only normal matter can collapse. Why is that?

Want to avoid getting “spaghettified” by a black hole? Steer clear of the smaller ones.