Search
Dark Energy
Nearly 100 years after being theorized, the strange behavior of the neutrino still mystifies us. They could be even stranger than we know.
The planet, the Solar System, and the galaxy aren't expanding. But the whole Universe is. So where does the dividing line begin?
For 13.8 billion years, the Universe has been expanding. But that couldn't have been the case for an eternity, and science has proven it.
Dark matter has never been directly detected, but the astronomical evidence for its existence is overwhelming. Here's what to know.
Observations with the Hubble space telescope helped cement dark energy and reveal the Hubble tension. How are these two things so different?
Inflation's two main criticisms, that it can predict anything and that the "measure problem" remains unsolved, can't erase its successes.
As the Universe ages, it continues to gravitate, form stars, and expand. And yet, all this will someday end. Do we finally understand how?
All of the matter that we measure today originated in the hot Big Bang. But even before that, and far into the future, it'll never be empty.
It's the origin of our entire observable Universe, but it's still not the very beginning of everything.
With several seemingly incompatible observations, cosmology faces many puzzles. Could early, supermassive stars be the unified solution?
As we look to larger cosmic scales, we get a broader view of the expansive cosmic forest, eventually revealing the grandest views of all.
The Universe isn't just expanding; the expansion is accelerating. If different methods yield incompatible results, is dark energy evolving?
When you don't have enough clues to bring your detective story to a close, you should expect that your educated guesses will all be wrong.
Throughout history, "free energy" has been a scammer's game, such as perpetual motion. But with zero-point energy, is it actually possible?
Just 13.8 billion years after the hot Big Bang, we can see 46.1 billion light-years away in all directions. Doesn't that violate...something?
On the largest scales, galaxies don't simply clump together, but form superclusters. Too bad they don't remain bound together.
The Big Bang was hot, dense, uniform, and filled with matter and energy. Before that? There was nothing. Here's how that's possible.
When the Hubble Space Telescope first launched in 1990, there was so much we didn't know. Here's how far we've come.
Once you cross a black hole's event horizon, there's no going back. But inside, could creating a singularity give birth to a new Universe?
The measured value of the cosmological constant is 120 orders of magnitude smaller than what's predicted. How can this paradox be resolved?
The relic signal that first proved the Big Bang has been known and analyzed for 60 years. Join us at the frontiers of modern cosmology!
In just its first 10 hours of observations, the Vera Rubin observatory discovered more than 2000 new asteroids. What else will it teach us?
For over 50 years, it’s been the scientifically accepted theory describing the origin of the Universe. It’s time we all learned its truths.
Is the Universe's expansion rate 67 km/s/Mpc, 73 km/s/Mpc, or somewhere in between? The Hubble tension is real and not so easy to resolve.
Different methods of measuring the Universe's expansion rate yield high-precision, incompatible answers. But is the problem robustly real?
A few physical quantities, in all laboratory experiments, are always conserved: including energy. But for the entire Universe? Not so much.
If you want to understand the Universe, cosmologically, you just can't do it without the Friedmann equation. With it, the cosmos is yours.
For decades, astronomers have claimed the Milky Way will merge with Andromeda in ~4 billion years. Here's why, in 2025, that seems unlikely.
If it weren't for the intricate rules of quantum physics, we wouldn't have formed neutral atoms "only" ~380,000 years after the Big Bang.
If all massive objects emit Hawking radiation, not just black holes alone, then everything is unstable, even the Universe. Can that be true?