Editing Tractor beam (section)

===1960s===
In July 1960, trade magazine ''Missiles and Rockets'' reported that Martin N. Kaplan, a research engineer at [[Ryan Aeronautical|Ryan Aeronautical Company]], had conducted experiments that could lead to an ability to direct an anti-gravitational force toward or away from a second body.<ref name="Force">{{cite journal | last1 = Force | date = 1960 | title = July 11 | journal = Missiles and Rockets | volume = 7 | issue = 2| page = 27 }}</ref>

In 1964, physicists Leopold Halpern of the [[Niels Bohr Institute]] and B. Laurent of the [[Nordic Institute for Theoretical Physics]] indicated general relativity theory and quantum theory allowed the generation and amplification of [[gravitons]] in a manner like the laser.<ref>{{cite journal | last1 = Halpern | first1 = L. | last2 = Laurent | first2 = B. | date = 1964 | title = Agosto. On the gravitational radiation of microscopic systems | journal = [[Il Nuovo Cimento]] | volume = XXXIII | issue = 3| pages = 728–751 | doi=10.1007/bf02749891| bibcode = 1964NCim...33..728H | s2cid = 121980464 }}</ref>  They showed, in principle, gravitational radiation in the form of a beam of [[graviton]]s could be generated and amplified by using induced, resonant emissions.