Physics

Abstract illustration of a figure reaching for a yellow sphere on the left, with colored overlapping circles and concentric arcs—evoking themes of physics and consciousness—set against a vibrant multicolored gradient background.
Many, from neuroscientists to philosophers to anesthesiologists, have claimed to understand consciousness. Do physicists? Does anyone?
Bright star at the center of a blue nebula radiates mass energy, surrounded by numerous smaller stars, with diffraction spikes visible from the brightest stars.
All stars shine due to an internal source of energy. Usually, it's nuclear fusion: converting mass into energy. What makes them most bright?
Photons come in every wavelength you can imagine. But one particular quantum transition makes light at precisely 21 cm, and it's magical.
globular cluster terzan 5
For centuries, even after we knew the Sun was a star like any other, we still didn't know what it was made of. Cecilia Payne changed that.
Text "Cosmic Origins" over a bright, colorful explosion effect with star-like patterns in the background.
Since the dawn of history, humans have pondered our ultimate cosmic origins. Now in the 21st century, science has gone beyond the Big Bang.
Two images of the Sombrero Galaxy reveal its beauty: one with a bluish hue showcasing visible details, and the other with a reddish hue highlighting a different spectrum. Captured by JWST, these images offer an unmatched view of this spiral galaxy's complex structure.
One of the most promising dark matter candidates is light particles, like axions. With JWST, we can rule out many of those options already.
warp field stars
Perhaps the most well-known equation in all of physics is Einstein's E = mc². Does mass or energy increase, then, near the speed of light?
anitmatter annihilation
From the tiniest subatomic scales to the grandest cosmic structures of all, everything that exists depends on two things: charge and mass.
MACS J0717 galaxy cluster dark matter
Dark matter doesn't absorb or emit light, but it gravitates. Instead of something exotic and novel, could it just be dark, normal matter?
black hole merger
The ultimate multi-messenger astronomy event would have gravitational waves, particles, and light arriving all at once. Did that just occur?
Astronomical image of a young star system with labeled features: jet, conical outflow, dark lane, possible spiral, disk, tail, and a scale marking 300 astronomical units.
A young, nearby, massive star, whose protoplanetary disk appears perfectly edge-on, was just viewed by JWST, with staggering implications.
An abstract geometric pattern of spirals and interlocking squares in white on a black grid background evokes the elegant precision often found at the intersection of mathematics and science.
Physicist Don Lincoln explains why mathematics is a powerful tool for scientific modeling, but is not a science itself.
proton internal structure
A proton is the only stable example of a particle composed of three quarks. But inside the proton, gluons, not quarks, dominate.
A supermassive black hole caught turning on reveals a mesmerizing cosmic dance, with bright streams of light and colorful gases swirling around it against a starry backdrop.
Seven years ago, an outburst in a distant galaxy brightened and faded away. Afterward, a new supermassive black hole jet emerged, but how?
A bright star emits light in a field of smaller, scattered stars against a dark sky.
Most stars shine with properties, like brightness, that barely change at all with time. The ones that do vary help us unlock the Universe.
Black and white abstract design featuring swirling, concentric patterns resembling a ripple effect with a yin-yang-like motif at the center.
Despite no experimental evidence showing that gravitons exist, they remain a respectable concept in the world of professional physicists.
A person seated in a wheelchair uses a communication device with a Stephen Hawking-like voice, blurred flowers gently framing the scene in the foreground.
Hawking’s refusal to upgrade his communication system preserved a voice that became iconic, not just for its sound, but for the profound identity it conveyed.
Sunlight, like a quantum sun, streams through tree branches, casting golden rays over a calm lake.
Despite the Sun's high core temperatures, atomic nuclei repel each other too strongly to fuse together. Good thing for quantum physics!
An abstract green fractal pattern resembling interconnected neural pathways on a black background evokes the complexity of a fractal universe.
On larger and larger scales, many of the same structures we see at small ones repeat themselves. Do we live in a fractal Universe?
Our galactic home in the cosmos — the Milky Way — is only one of trillions of galaxies within our Universe. Is one of them truly our "twin?"
A digital vortex with glowing cyan concentric circles and geometric shapes giving a sense of depth and motion.
The problem for galactic-scale civilizations comes down to two numbers.
atoms
If atoms are mostly empty space, then why can't two objects made of atoms simply pass through each other? Quantum physics explains why.
einstein general relativity curved spacetime
Most waves need a medium to travel through. But the way that light and gravitational waves travel shows that space can't be a medium at all.
Close-up of an analog weight scale needle pointing to zero grams, with a black background.
"A person’s mass is made not of 'stuff' in the way we normally think about it, but rather our mass is made of energy."
An illustration of Galileo Galilei with a historical text and a lunar sketch alongside.
"I was stunned. Here in front of me was the original apparatus through which a new vision of the world was slowly and painfully brought to light."
Global geoid map with colorful variations representing differences in Earth's gravity field. The scale ranges from -100 (low) to 100 (high). Europe's position is central.
Scalars, vectors, and tensors come up all the time in physics. They're more than mathematical structures. They help describe the Universe.
quantum mechanics
Our classical intuition is no good in a quantum Universe. To make sense of it, we need to learn, and apply, an entirely novel set of rules.
A golden-brown turkey being carefully lowered into a metal pot outdoors, ready for a deep fry amidst the grassy area and wooden fence.
It's the ultimate setup for a Thanksgiving Day disaster. The physics of water and its solid, liquid, and gas phases compels us not to do it.
A Rubik's cube with a red X floats in space, next to a planet and moon—each marked with green checkmarks—that boast their perfect round shape.
All the stars, stellar corpses, planets, and other large, massive objects take on spherical or spheroidal shapes. Why is that universal?
A large group of people with red hair gather outdoors, many wearing white clothing.
Whether your hair is straight, wavy, curly, or kinky isn't just genetic in nature. It depends on the physics of your hair's very atoms.