Weak and strong gravitational fields can be produced by a single continuously circulating unidirectional beam of light. In the weak gravitational field of a unidirectional ring laser, it is predicted that a spinning neutral particle, when placed in the ring, is dragged around by the resulting gravitational field.
Ron Mallett has new exact solutions of the Einstein field equations for the exterior and interior gravitational fields of the light cylinder.
Ron Mallet has found the exterior gravitational field contains closed timelike lines. The strong gravitational field can be produced by a circulating cylinder of light.
The closed timelike lines indicates the possibility of time travel into the past.
There is coverage of Mallett work by CNN.
A paper on Arxiv argues that it would take too much energy to generate gravitational effects.
The general theory of relativity indicates that both matter and energy can create a gravitational field. The energy of a light beam can produce a gravitational field.
Brian Wang is a prolific business-oriented writer of emerging and disruptive technologies. He is known for insightful articles that combine business and technical analysis that catches the attention of the general public and is also useful for those in the industries. He is the sole author and writer of nextbigfuture.com, the top online science blog. He is also involved in angel investing and raising funds for breakthrough technology startup companies.
He gave the recent keynote presentation at Monte Jade event with a talk entitled the Future for You.  He gave an annual update on molecular nanotechnology at Singularity University on nanotechnology, gave a TEDX talk on energy, and advises USC ASTE 527 (advanced space projects program). He has been interviewed for radio, professional organizations. podcasts and corporate events. He was recently interviewed by the radio program Steel on Steel on satellites and high altitude balloons that will track all movement in many parts of the USA.
He fundraises for various high impact technology companies and has worked in computer technology, insurance, healthcare and with corporate finance.
He has substantial familiarity with a broad range of breakthrough technologies like age reversal and antiaging, quantum computers, artificial intelligence, ocean tech,  agtech, nuclear fission, advanced nuclear fission, space propulsion, satellites, imaging, molecular nanotechnology, biotechnology, medicine, blockchain, crypto and many other areas.