Tractor beams that can move anything?
Tractor beams are a staple of science fiction, but they have long been thought to be impossible in the real world. However, recent research has shown that it is possible to create tractor beams using optical or acoustical waves. In a study published in the journal Physical Review A, researchers from the Vienna University of Technology have developed a method for creating tractor beams with optimal pulling force. Their method relies on the solution of a simple eigenvalue problem involving the system's measurable scattering matrix. The researchers demonstrated the efficacy of their method using numerical simulations for a representative set of different targets. They also showed that the diffractive nature of waves enables the possibility of a tractor beam that works even for targets where a geometric optics approach fails to explain the pulling forces. The development of tractor beams with optimal pulling force could have a wide range of potential applications. For example, they cou...