The term "reduced to practice" means that the inventor has at least specified an invention in words, drawing, or other means to the extent that anyone familiar with the field of technology to which the invention pertains would be able to make, implement, or perform ("practice") the invention. "Reduced to practice" does not mean that the inventor has made or done the thing claimed as his or her invention -- except that the patent examiner has the authority to require an inventor to demonstrate any claim that seems to violate accepted scientific principles.