Autotranslation:

https://translate.google.com/translate?hl=&sl=auto&tl=en&u=h...

> The study was carried out from January 2020 to December 2020. [...] It does not provide any highly scientific evidence, but does provide numerous and serious evidence:

Even the press release of the university acknowledges that It does not provide any highly scientific evidence.

> The study is published at: http://doi.org/10.13140/RG.2.2.31754.80323 .

Note that this is a link to a preprint in ResearchGate, not a peer review article. This has the same checks levels than a blog post in WordPress. It is "published" but essentially anyone can publish there whatever they want.

his sources are basically YouTube and other unproven articles, mostly from far right extremist sites.

German truth check article for that one: https://www.volksverpetzer.de/uncategorized/uni-hamburg-unwi...

Within one day of the press release this has drawn so much negative attention in Germany that this "study" became a major embarrassment for the university and its press department. Now they are mostly concerned with damage limitation...

English paper: https://www.researchgate.net/publication/349302406_Studie_zu...

Physicist professor.