kiertoaikoneen

Kiertoaikoneen, also known as a *perpetual motion machine* in English, refers to a hypothetical mechanical device that can operate indefinitely without an energy input. The concept has fascinated scientists, inventors, and the general public for centuries, though it is widely regarded as impossible according to the known laws of physics.

The idea of perpetual motion is often divided into two categories: first kind and second kind. A first-kind perpetual motion machine would violate the first law of thermodynamics, which states that energy cannot be created or destroyed, only transformed. Such a machine would produce more energy than it consumes, seemingly creating energy from nothing. A second-kind perpetual motion machine would violate the second law of thermodynamics, which asserts that in any energy transfer or transformation, some energy is always lost as waste heat, increasing the entropy of a closed system. This type of machine would theoretically keep moving without any loss of energy, operating in a perpetual cycle without friction or other dissipative forces.

Historically, numerous inventors have claimed to have built working perpetual motion machines, often promoting them as revolutionary solutions to energy problems. However, upon closer examination, these devices typically fail to meet the criteria for perpetual motion due to overlooked energy inputs, such as gravitational potential energy, residual energy in components, or external forces acting on the system. Scientific consensus holds that perpetual motion is impossible under classical physics, though some interpretations of quantum mechanics and relativity have explored theoretical scenarios where energy conservation might appear to be violated in specific contexts.

Despite its impossibility, the concept of perpetual motion remains a popular topic in physics, engineering, and popular culture. It serves as a thought experiment to illustrate fundamental principles of thermodynamics and the conservation of energy, as well as a cautionary tale about the importance of rigorous scientific testing and peer review in evaluating technological claims.