Understand matter based on the Pauli exclusion principle
Matter as defined by the Pauli exclusion principle.
© MinutePhysics (A Britannica Publishing Partner)
-
Encyclopædia Britannica, Inc.A hurricane is essentially a large tropical storm.
-
© MinuteEarth (A Britannica Publishing Partner)The role of the Rocky Mountain locust (Melanoplus spretus) in the Grasshopper Plague of 1874–75 (which is also known as the Great North American Locust Plague), and the insect's mysterious disappearance that followed.
-
Encyclopædia Britannica, Inc.Learn more about the problem of climate change in this interview with Bill McKibben.
-
© MinutePhysics (A Britannica Publishing Partner)Learn about antimatter and its properties.
-
Encyclopædia Britannica, Inc.Artemis II is sending human organs around the Moon. Why?Media Editor: Lauren Sims
-
© MinutePhysics (A Britannica Publishing Partner)A lesson on how small things, like electrons and protons, can behave like both a particle and a wave.
-
© MinutePhysics (A Britannica Publishing Partner)Astrophysicist Neil deGrasse Tyson narrating a brief history of the universe, from the big bang to the present.
News •
Scientists achieve record-breaking low temperature on China's space station, paving the way for new physics experiments
• Nov. 6, 2026, 12:00 PM ET (Phys.org)
Scientists Trapped an Antimatter Particle for Months to Study Its Secrets
• Oct. 25, 2026, 8:00 AM ET (WIRED)
Transcript
Matter is everywhere. We eat it, breathe it, drink it. It is who we are. But what is matter? The most basic particle physics definition of matter comes down to one surprising rule. The Pauli exclusion principle, or essentially, electrons hate being alike. To understand why, we have to remember the fact that every electron is exactly the same. Not kind of the same, they're perfectly identical.
Just as you can, at any time, anywhere, spontaneously, write down the number three, and it will mean exactly, perfectly three, as if there were some everywhere permeating three-ness, always available to produce a three at your whim. It's the same case with the electron. There's an everywhere permeating electron-ness called quantum field, and from that field every electron in existence has been summoned, and they are all exactly electrons. So when someone says, every time you breathe you inhale a few of the same electrons that used to be in Jesus or Mozart, that's about as deep as saying that every time you do arithmetic you use the same number three as Archimedes.
What's more, just like you can call on the three-ness to summon negative 3, which has all the exact same properties of three except opposite, and when it meets three, they annihilate, you can summon anti-electron from the electron field and they will annihilate electron when they meet. So given that electrons are all exactly alike, it's a little surprising that they actually hate being like each other. In fact, electrons despise alikeness so much that the universe is forbidden from summoning two or more into the same quantum state.
This is called the Pauli exclusion principle, and what it means in practice is that you can't cram too much matter into the same place-- like a city, where building higher than one story is prohibited. Instead of skyscrapers, compounds sprawl outwards. So at the most fundamental level, matter is just any field, like electron, quark, or neutrino, from which you can summon particles and anti-particles, but only one at every point, which means that, quite literally, matter is everything that takes up space.
Just as you can, at any time, anywhere, spontaneously, write down the number three, and it will mean exactly, perfectly three, as if there were some everywhere permeating three-ness, always available to produce a three at your whim. It's the same case with the electron. There's an everywhere permeating electron-ness called quantum field, and from that field every electron in existence has been summoned, and they are all exactly electrons. So when someone says, every time you breathe you inhale a few of the same electrons that used to be in Jesus or Mozart, that's about as deep as saying that every time you do arithmetic you use the same number three as Archimedes.
What's more, just like you can call on the three-ness to summon negative 3, which has all the exact same properties of three except opposite, and when it meets three, they annihilate, you can summon anti-electron from the electron field and they will annihilate electron when they meet. So given that electrons are all exactly alike, it's a little surprising that they actually hate being like each other. In fact, electrons despise alikeness so much that the universe is forbidden from summoning two or more into the same quantum state.
This is called the Pauli exclusion principle, and what it means in practice is that you can't cram too much matter into the same place-- like a city, where building higher than one story is prohibited. Instead of skyscrapers, compounds sprawl outwards. So at the most fundamental level, matter is just any field, like electron, quark, or neutrino, from which you can summon particles and anti-particles, but only one at every point, which means that, quite literally, matter is everything that takes up space.
Last Modification: