Since this was done in a powerful electromagnetic field, that energy field yielded matter, the reverse of burning matter to create energy. Matter and energy are related, and perhaps this experiment shows that they can be converted. That should surprise no one.
Matter and energy are not just related, they are identical. What we call matter and energy are just different manifestations of the same physical phenomenon.
Since this was done in a powerful electromagnetic field, that energy field yielded matter, the reverse of burning matter to create energy. Matter and energy are related, and perhaps this experiment shows that they can be converted. That should surprise no one.
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Well you are not going to learn whether that is true from reading this poorly written article. The claim of something and minus something from nothing infers that no energy was taken from the electromagnetic field. If you cannot demonstrate that is the case then you have nothing.
So your theory is much more likely. Something from something else.