Quantum physics shows that particles don’t act like solid objects in a fixed place. They act more like waves, meaning we can’t know their exact location. But in many everyday situations, scientists can still describe particles in a simple, familiar way – as tiny objects moving with a certain speed.
This simple approach works well when explaining how electricity flows through metals. Physicists often describe electric current as electrons moving through a material, pushed and redirected by forces.
Why the Particle Idea Usually Works
Many modern theories also use this particle idea, including theories about topological states of matter. the discovery of these states was so critically important it won the Nobel Prize in Physics in 2016. Even though the math behind these theories is complex, they still assume electrons act like particles with defined movement.
However, researchers have found this isn’t true for all materials. In certain specific cases, electrons don’t act like individual particles with a clear position or speed.
Topology Without Particles
Scientists at TU Wien have shown that materials can still have topological properties even when the particle idea doesn’t work. Until now, people thought these properties depended on particle-like behavior.
This finding is surprising. It shows that topological states aren’t limited to systems where electrons act like particles. These states are actually more worldwide, connecting ideas that once seemed different.
When the Particle Idea Doesn’t Make Sense
“The idea of electrons as small particles bumping into things as they flow as electricity is strong,” says Prof. Silke Bühler-Paschen from the Institute of Solid State Physics at TU Wien. “With some adjustments, it even works in complex materials where electrons interact a lot.”
But there are extreme cases where this idea breaks down. In these cases, the charge carriers lose their particle-like nature. This happens in a material made of cerium,ruthenium,and tin (cerusn),which researchers at TU Wien studied at vrey low temperatures.
“Near absolute zero, it shows a specific type of quantum behavior,” says Diana Kirschbaum, who led the research. “The material fluctuates between two states, like it can’t decide which one to choose. In this fluctuating state, the particle idea doesn’t seem to work.”
Topology Explained With Shapes
Simultaneously occurring, theoretical work suggests…