Carroll has written that both human brains and the spoons they try to bend are made, like all matter, of quarks and leptons; everything else they do emerges as properties of the behavior of quarks and leptons. And the quarks and leptons interact through the four forces: strong, weak, electromagnetic and gravitational. Thus either it is one of the four known forces or it is a new force, and any new force with range over 1 millimetre must be at most a billionth the strength of gravity or it will have been captured in experiments already done. This leaves no physical force that could possibly account for psychokinesis. Physicist John G. Taylor who investigated parapsychological claims has written an unknown fifth force causing psychokinesis would have to transmit a great deal of energy. The energy would have to overcome the electromagnetic forces binding the atoms together. The atoms would need to respond more strongly to the fifth force while it is operative than to electric forces. Such an additional force between atoms should therefore exist all the time and not during only alleged paranormal occurrences. Taylor wrote there is no scientific trace of such a force in physics, down to many orders of magnitude; thus if a scientific viewpoint is to be preserved the idea of any fifth force must be discarded. Taylor concluded there is no possible physical mechanism for psychokinesis and it is in complete contradiction to established science. Felix Planer, a professor of electrical engineering, has written that if psychokinesis was real then it would be easy to demonstrate by getting subjects to depress a scale on a sensitive balance, raise the temperature of a water bath which could be measured with an accuracy of a hundredth of a degree Celsius or affect an element in an electrical circuit such as a resistor which could be monitored to better than a millionth of an ampere. Planer writes that such experiments are extremely sensitive and easy to monitor but are not utilized by parapsychologists as they "do not hold out the remotest hope of demonstrating even a minute trace of PK" because the alleged phenomenon is non-existent. Planer has written parapsychologists have to fall back on studies that involve only statistics that are unrepeatable, owing their results to poor experimental methods, recording mistakes and faulty statistical mathematics. According to Planer, "all research in medicine and other sciences would