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Cosmic Inflation
The James Webb Space Telescope finally could answer the age-old question of whether we are alone in the universe.
There are two fundamentally different ways of measuring the Universe's expansion. They disagree. "Early dark energy" might save us.
From before the Big Bang to the present day, the Universe goes through many eras. Dark energy heralds the final one.
Known as primordial black holes, they could thoroughly change our Universe's history. But the evidence is strongly against them.
A wild, compelling idea without a direct, practical test, the Multiverse is highly controversial. But its supporting pillars sure are stable.
We know it couldn't have began from a singularity. So how small could it have been at the absolute minimum?
Although most of the Universe's mass is dark matter, which gravitates just as well as normal matter, it still can't make black holes.
But the upcoming James Webb Space Telescope compels us to add, “so far.” Beginning with its 1990 launch, NASA’s Hubble Space Telescope revolutionized our conception of the Universe. This photo of […]
The highest-energy particles of all come from space, not human-made colliders. When it comes to the most energetic particle collisions of all, you might think that the Large Hadron Collider […]
Once merely a theoretical curiosity, they might be the key to understanding so much more. Out of all of the known particles — both fundamental and composite — there are a whole slew of properties […]
If it wasn’t a singularity, how small could it have been? Today, when you look out in any direction as far as the laws of physics allow us to see, the […]
It could evolve, strengthen, decay, or not be alone. Our known Universe contains matter, radiation, and dark energy. While matter (both normal and dark) and radiation become less dense as […]
Despite the recent headlines, it’s an extraordinarily unlikely proposition. Have you ever wondered, if it were possible to travel through space straight ahead as quickly as you could imagine, if […]
Yes, the Big Bang is real, but what about what came before? If you ask anyone about the origin of some phenomenon that we’ve observed, they’ll usually default to the same […]
The rarest stars in the Universe are the ones we need the most to make humanity possible. Like everything in the Universe, stars are born, they live a little while, […]
Is the Universe the same everywhere? Or are there truly ‘special places’ around? For practically all of human history, one assumption about our place in the Universe had long gone unchallenged: […]
How two seemingly distinct exoplanet systems turned out to be related. Practically every star in the Milky Way has a similar origin story. At some point in the past, a molecular […]
Three of our dimensions are spatial and one is temporal, but could there be more? From any point in space, you are free to move in any direction you choose. No […]
Our galaxy not only isn’t stationary, but different parts are accelerating at different rates. When we think about the Universe as a whole, the accelerations that objects experience from our […]
It’s a wild idea, but there’s a way to test it. No matter how far we look out in the Universe, there’s always more “Universe” to see. Even at the extreme […]
Has all this happened before, and will all this happen once again? There are only a few questions, when we ask them, that force us to reckon with the fundamental nature […]
If it weren’t for a subatomic quantum rule, our Universe would be vastly different. In many ways, our views of the distant Universe are the closest things we’ll ever get […]
Cosmic rays aren’t just limited by the speed of light. Even among non-scientists, it’s well-understood that there’s an ultimate speed limit to the Universe: the speed of light. If you’re a […]
Complex organisms and living worlds couldn’t exist without these transitions. You couldn’t make the Universe we have today if everything were always the same. Although many philosophically favored the idea […]
If you want to know what the Universe is like, you have to look at it in the right way. Only by observing it can we know what the Universe is […]
The most massive nearby stars could be the seeds our supermassive black holes need. The problem with the Universe, as we see it today, is that we only get a snapshot […]
Even before the Big Bang, energetic radiation was always present. When it comes to the physical Universe, the notion of “nothing” may truly be possible only in theory, not in […]
It could have had any curvature at all. So why is it flat? What is the shape of the Universe? If you had come along before the 1800s, it likely never […]
If you want to get the Universe we see, a multiverse comes along for the ride. When we look out at the Universe today, it simultaneously tells us two stories about […]
We have two ways of measuring the expansion rate. Here’s the harder one. If you want to understand where our Universe came from and where it’s going, you need to measure […]