Defocus aberrationIn optics, defocus is the aberration in which an image is simply out of focus. This aberration is familiar to anyone who has used a camera, videocamera, microscope, telescope, or binoculars. Optically, defocus refers to a translation of the focus along the optical axis away from the detection surface. In general, defocus reduces the sharpness and contrast of the . What should be sharp, high-contrast edges in a scene become gradual transitions. Fine detail in the scene is blurred or even becomes invisible.
Quantum teleportationQuantum teleportation is a technique for transferring quantum information from a sender at one location to a receiver some distance away. While teleportation is commonly portrayed in science fiction as a means to transfer physical objects from one location to the next, quantum teleportation only transfers quantum information. The sender does not have to know the particular quantum state being transferred. Moreover, the location of the recipient can be unknown, but to complete the quantum teleportation, classical information needs to be sent from sender to receiver.
Ghost huntingGhost hunting is the process of investigating locations that are purportedly haunted by ghosts. Typically, a ghost-hunting team will attempt to collect evidence supporting the existence of paranormal activity. Ghost hunting has been heavily criticized for its dismissal of the scientific method. No scientific study has ever been able to confirm the existence of ghosts. The practice is considered a pseudoscience by the vast majority of educators, academics, and science writers.
Delayed-choice quantum eraserA delayed-choice quantum eraser experiment, first performed by Yoon-Ho Kim, R. Yu, S. P. Kulik, Y. H. Shih and Marlan O. Scully, and reported in early 1998, is an elaboration on the quantum eraser experiment that incorporates concepts considered in John Archibald Wheeler's delayed-choice experiment. The experiment was designed to investigate peculiar consequences of the well-known double-slit experiment in quantum mechanics, as well as the consequences of quantum entanglement.
Hungry ghostHungry ghost is a term in Buddhism, and Chinese traditional religion, representing beings who are driven by intense emotional needs in an animalistic way. The terms 餓鬼 èguǐ literally "hungry ghost", are the Chinese translation of the term preta in Buddhism. "Hungry ghosts" play a role in Chinese Buddhism and Taoism as well as in Chinese folk religion. The term is not to be confused with the generic term for "ghost" or damnation, 鬼 guǐ (i.e. the residual spirit of a deceased ancestor).
