 In 1995, William Nevins published a criticism  arguing that the particles inside fusors and polywells would build up angular momentum, causing the dense core to degrade.In 1995, the University of Wisconsin–Madison built a large fusor, known as HOMER, which is still in operation.Meanwhile, Dr George H. Miley at Illinois, built a small fusor that has produced neutrons using deuterium gas  and discovered the "star mode" of fusor operation.