process

particle interaction

The ways in which subatomic particles, like neutrons and protons, influence each other.
12 related articles

Description

Particle interaction refers to the fundamental ways in which subatomic particles, such as neutrons, protons, and electrons, influence each other through forces. These interactions are the basis of all matter and energy in the universe, from the stability of atomic nuclei to the fusion reactions in stars. Understanding these interactions is essential for describing the behavior of matter at the smallest scales.

History

The modern understanding of particle interactions was developed in the 20th century, with key contributions from quantum field theory. The Standard Model of particle physics, finalized in the 1970s, describes the electromagnetic, weak, and strong forces, while gravity remains outside this framework.

How it works

Particles interact through the exchange of force-carrying particles. For example, the strong nuclear force, which binds protons and neutrons in the nucleus, is mediated by gluons. The electromagnetic force, which acts between charged particles, is mediated by photons. These exchanges transfer momentum and energy, causing particles to attract, repel, or transform.

In practice

Particle interactions are harnessed in technologies like particle accelerators (e.g., CERN's LHC) for research, and in medical imaging and cancer treatment via proton therapy.

Fun fact

The strong force is so powerful that it holds quarks together inside protons, but it becomes weaker at very short distances, a property known as asymptotic freedom.

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Related articles · 12

The Hidden Wind of Neutron Stars: How Neutrons Propel Magnetic Vortices
The interiors of neutron stars are a realm of degenerate matter. Here, protons condense into a superconducting condensate, threaded by quantum vortices. Imagine tiny magnetic tops: each carries a quantum of magnetic flux and glides through the electron fluid.
HEP Phenomenology2026-06-152 minarXiv:2606.17133express
Pair Tango Inside the Proton
At accelerators, by smashing heavy nuclei, physicists briefly create a quark-gluon plasma — a state of matter where quarks and gluons are not confined inside particles but are free. For a long time, it was imagined as a gas, but experiments showed it's an almost perfect liquid.
HEP Phenomenology2026-05-262 minarXiv:2605.27506express
Neutrinos Don't Want to Get Married
A swarm of fireflies rarely collides, yet they synchronously change color by exchanging signals. This is how neutrinos behave in dense streams from collapsing stars: they collectively transform from one type to another, even though individually they interact extremely weakly.
physics.ed-ph2026-05-201 minarXiv:2605.21626express
A Magnetic Remote for Atoms
In the orchestra of atoms, each instrument has its own score. But sometimes two musicians start playing in unison, and the sound amplifies many times over. In the quantum world, this 'harmony' is called a Feshbach resonance. It allows you to control atomic interactions with jeweler-like precision.
Nuclear Experiment2026-05-122 minarXiv:2605.12626express
How the Atomic Nucleus Becomes a Dance Floor
At first glance, the atomic nucleus is a cramped communal apartment where protons and neutrons (together called nucleons) live by strict rules. Each occupies its own orbit, like electrons in an atom, and on average everything looks orderly.
Nuclear Theory2026-04-292 minarXiv:2604.26876express
How the Thickness of a Neutron Skin Reveals the Heart of Dead Stars
An atomic nucleus is like a droplet with a thin coating — a neutron 'skin.' Inside the droplet, protons and neutrons are mixed evenly, but on the outside, like the froth on milk, a layer forms where neutrons are noticeably more abundant.
HEP Phenomenology2026-04-231 minarXiv:2604.21652express
Neutron Stars as Dark Matter Detectors
A neutron star is the dead core of a massive star, crushed to the size of a city. A teaspoon of its material weighs as much as a mountain. Dark matter particles fly through such a dense medium almost unimpeded, but occasionally they do hit neutrons and get stuck, like bullets bogging down in deep sand.
HEP Experiment2026-04-141 minarXiv:2604.12364express
A Universal Physicist from a Foreign Experiment
A neural network trained on collisions of protons and electrons transferred its skills to a completely different experiment — catching neutrinos. Like a chef who learned French cuisine and then, without preparation, baked an excellent Uzbek plov.
HEP Experiment2026-04-141 minarXiv:2604.13231express
A Mirror for Antiprotons
When particles collide at enormous speeds, they produce a shower of new particles. Among them are antiprotons — twins of ordinary protons but with the opposite charge. Each of these particles has its own spin, like a tennis ball sent with a twist. But whether antiprotons are actually spun up at birth has never been checked.
Nuclear Experiment2026-02-241 minarXiv:2602.21325express
How the Atomic Nucleus Quenches Particle Jets
The Large Hadron Collider doesn't just smash protons: it also collides entire atomic nuclei. When two nuclei smash together at tremendous speed, they create a tiny blob of matter so hot that protons and neutrons melt into a 'soup' of quarks and gluons.
Mesoscale2026-02-071 minarXiv:2602.07691express
Light Spins Up the Spins
A beam of circularly polarized light hits a MAPbI3 perovskite crystal. The electrons inside start behaving like tiny spinning tops, their axes aligning along the beam. This phenomenon is known as optical spin orientation.
A Faint Breeze That Chooses a Snowflake's Shape
A snowflake falling from a cloud chooses between a left-handed and a right-handed form. The difference between them is almost imperceptible, like a breath of wind, yet it is that very breath that decides which pattern will grow.