A long time time ago Corben and Schwinger [1] discovered a controversy in the Coulomb problem for W-bosons. The charge of the vector boson located on the attractive Coulomb centre proves be infinite, which indicates that the boson falls on the centre. This does not make physical sense, signalling therefore a serios difficulty.
This problem is related to the modern-day studies because the formalism for vector bosons proposed by Corben and Schwinger can be derived within the frames of the modern Electroweak Theory (though Ref.[1] was written before the discovery of the Yang-Mills fields, Electroweak Theory and Standard Model).
Thus, for 65 years there existed a puzzle. One can formulate the Coulomb problem for W bosons, but one cannot find its acceptable solution.
Recent works Refs.[2,3] resolve the difficulty using an unexpected physical idea. They notice that an additional potential created by the vacuum polarization eliminates the "silly" infinite charge. After that the Coulomb problem becomes a nice, well defined member of a theoretical zoo, getting in line with the Standard Model.
The found solution uses a simple, clear physical idea, called the QED vacuum polarization, which was one of the first effects discovered in QED. Interestingly, it was known at the time when Ref.[1] was published.
Of course, there should be a trick, otherwise the trouble could not survive a second, leave along decades. The trick is in perception of the vacuum polarization
Firstly, in conventional situations the vacuum polarization in QED produces a very small effect. So expect something small from it, why care about it when there are infinities around.
Secondly, the QED polarization usually plays an attractive role, enlarging the charge located at the origin. It seems therefore impossible to use the QED polarization for reducing the charge at the origin.
Refs.[2,3] claim though that for vector bosons the situation is absolutely opposite. The polarization produces a huge, repulsive effect. To see that this claim is correct, it is necessary to go into details, see[2,3]. Once one this fact is established, the rest is really simple.