Science

https://massivesci.com/articles/anita-experiment-physics-neutrinos/
When the research team looked at the collected data in 2016, two of the observations looked like “cosmic rays [that] had come out of the ice itself. A very strange thing,” in the words of Peter Gorham, the principal investigator of the experiment. Neutrinos do routinely pass through the entire Earth without stopping and could give off this signal upon exiting the Antarctic surface, but definitely not when they have the very high energies that the experiment measured.

The “ANITA anomalies” attracted a cautious amount of attention in the elementary particle physics community: they are one of the very few findings incompatible with the established theoretical framework, but at the same time, any overlooked issues with the experiment itself could probably produce similar results.
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As for the anomalies in the ANITA findings, the prospects for their clarification are alive and well. A number of “simple” explanations are still on the table, including a recent one that the signals in question came from above and were only reflected by the ice. This is a scenario that the researchers had already considered and ruled out: reflection can usually be detected by specific changes that it causes in the radio signal. However, another research team suggested that these changes do not occur when radio signals are reflected by layers of thinner ice underneath the surface, a common feature in Antarctica’s landscape. If this is confirmed then the strange measurements will turn out to be ordinary, everyday cosmic rays.

Meanwhile the scientists behind ANITA, when not busy un-hyping their work, are preparing an upgraded version of the experiment: PUEO, a larger antenna-carrying balloon, expected to be more efficient in catching radio signals when it flies next year. Its operation will offer more clues about both the nature of the anomalies and possible previous experimental issues, while carrying out its mission of studying energetic neutrinos from space.
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In a nutshell, there are more likely explanations than evidence of another universe, and running backwards to boot. The site seems good and has comments from actual scientists. It also explains why detecting evidence of neutrinos coming through the earth was anomalous, which was bothering me.