Quantum simulators are quantum systems that can be controlled exceptionally well. They can be used to indirectly learn something about other quantum systems, which cannot be experimented on so easily. Therefore, quantum simulators play an important role in unraveling the big questions of quantum physics. However, they are limited by temperature: They only work well, when they are extremely cold. Scientists have now developed a method to cool quantum simulators even more than before: by splitting a Bose-Einstein-condensate in half, in a very special way.