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"Theoretically, it interacts with gravity, but it has no interaction with the others, weak nuclear force, strong nuclear force or electromagnetic force," Sousa said.

The Standard Model encompasses four forces: the strong nuclear force, the weak nuclear force, the electromagnetic force, and the gravitational force.

However, the weak nuclear force is exceptionally difficult to study as it is overshadowed by the much greater effects of the strong nuclear and electromagnetic forces.

Scientists have gained new insights into the weak nuclear force from detailed studies of the beta decays of the "mirror" nuclei lithium-8 and boron-8.

Scientists have performed a new, more sensitive measurement of beta decay properties to hunt for a theorized feature of the weak nuclear force not currently included in the Standard Model.