Berkelium is a synthetic, radioactive element that was first made at the Lawrence Berkeley National Laboratory located in Berkeley, California (hence the name "berkelium") in 1949. It is a soft, silver-white metal and a member of the actinide family, which are the among least explored elements of the periodic table. Some of berkelium's atomic features is rather puzzling to scientists.
Quantum mechanism is often used to interpret the behavior of particles at the atomic and subatomic level. For example, the arrangement of electrons within an atom abides by the rule of quantum physics: the exact position of a particular electron stays unidentifiable until someone makes a measurement.
However, in berkelium the other main principal of physics, Einstein's theory of special relativity, is more apt to explain what's going on within the atom: the fast-moving electrons make the atom appear heavier, or cause a bigger dent in the space-time fabric.
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