Scientists at the Australian National University (ANU) have achieved something that sounds almost impossible: they have observed atoms existing in two places at the same time.
This unusual behavior, predicted by quantum physics more than a century ago, has now been demonstrated more clearly than ever using real, massive particles.
In everyday life, objects can only be in one place at a time. But in the strange world of quantum mechanics, particles such as atoms can behave very differently.
They can exist in multiple locations simultaneously, a phenomenon often described as “superposition.”
While this idea has been tested many times with particles of light, or photons, showing it with atoms has been much more difficult.
The ANU team used helium atoms for their experiment. Unlike photons, helium atoms have mass, which makes them more similar to the physical matter we interact with every day.
Because of this, they can be cooled, trapped, and even influenced by gravity. This makes them especially useful for exploring deeper questions about how the universe works.
Lead researcher Yogesh Sridhar Arthreya explained that demonstrating this effect experimentally is extremely challenging.
Many scientists have tried to observe this kind of behavior in atoms before, but their efforts fell short.
In this new study, the team was able to not only place atoms into a state where they exist in two locations, but also show that these states are linked together through a phenomenon called entanglement.
Entanglement means that two particles become connected in such a way that the state of one instantly influences the other, even if they are separated by distance.
In this case, the atoms were entangled in their motion, meaning their positions and movements were linked across space. This is a key feature of quantum physics and one that scientists are still trying to fully understand.
Dr. Sean Hodgman from the ANU Research School of Physics described the result as both exciting and deeply strange.
While the theory behind these effects has been known for decades, seeing it happen with atoms makes it feel more real. It shows that the unusual rules of quantum physics are not just abstract ideas, but actual features of the physical world.
The findings, published in Nature Communications, open up new possibilities for studying one of the biggest mysteries in science: how quantum mechanics, which governs the smallest scales, connects with gravity and the large-scale structure of the universe.
These two areas of physics are currently described by different theories that do not fully agree with each other.
By using atoms instead of light, researchers now have a new tool to explore this gap. While this experiment does not yet provide a complete answer, it represents an important step forward.
It brings scientists a little closer to understanding whether a unified “theory of everything” is possible, or whether the universe is even stranger than we currently imagine.
