let's also mention an old well-documented case of close encounters with UFOs and direct contact with them. In short, it is about a group of students who, while playing in the field, come across a strange device of unknown origin... If you read the article carefully here (http://web.archive.org/web/20160112124944/http:/%20/nerazgadano.info/2016/01/sreshtite-s-miniatyurnoto-nlo-ot-kera/) or here (https://lucecita.blog.bg/drugi/2013/07/23/mini%20-nlo-ot-kera-iaponiia.1132842) you will see that two moments clearly stand out [if you were not previously familiar with the materials and details regarding the flying platform of V. S. Grebennikov, one would not turn at all attention]. The first moment is related to the configuration of holes observed in the experiments (https://youtu.be/AYYx4Kef3Tc?t=97) of enthusiasts on the effect of cavity structures. The second moment is the description in the article of the peculiarities exhibited by the mini-UFO, which directly correspond to the characteristics related to Grebennikov's flying platform [inability to operate in a wet environment]. The boys managed to peek through a gap inside the device, it turned out that there were complex electronics, most likely the device was some kind of high-tech drone of an advanced unknown extraterrestrial civilization or some secret earth organization, designed to carry out a certain mission.
https://i.imgur.com/tVBLJ8R.png
https://www.youtube.com/v/AKSUP3_zwLg
https://www.youtube.com/v/l0wsFlq2IR0
sources:
http://www.kosmopoisk.ru/artefacts/70/
http://ufojikenbo.blogspot.com/2015/11/kera.html
In 2022, there was some movement about Grebennikov.
The daughter of a friend of Grebennikov, the Soviet scientist Valentin Zolotarev, published some very extensive information about the biography and scientific activities of her father.
From this it becomes clear, presumably, that most likely Grebennikov composed a fantasy novel based on conversations with the scientist Valentin Zolotarev.
In the 1960s, the scientific organization where Valentin Zolotarev worked tried to use structures similar to biostructures to create various electronic and optoelectronic devices.
https://overunity.com/15371/viktor-grebennikov-anti-gravity-levitation/msg564199/#msg564199 (https://overunity.com/15371/viktor-grebennikov-anti-gravity-levitation/msg564199/#msg564199)
Conclusion:
In reality, Grebennikov had no chance of realizing anti-gravity without the help of an all-powerful scientific organization in Moscow, where his friend Valentin Zolotarev worked. :'(
But have there been any developments in this direction? Could Zolotarev carry out these developments in secret? Could Zolotarev provide Grebennikov with some of the most important parts of the anti-gravity platform illegally?
What can be discussed? Some kind of nanosized cavity ordered structures that can theoretically be fabricated by the same methods that processors are currently manufacturing. But in those days, such technologies, at the nanoscale level, were not yet available.
I am inclined that Zolotarev also provided only hypothetical information, which at that time was unrealizable.
Or it could just be the spring coil from an old pull cord music toy
Probably encoded with a lullaby