Isn’t it nice when someone does your work for you?  For some years now, NIL Technololgy have been sending me science news emails as a form of advertising.  Mostly these are to do with nanotechnology, but the most recent directed me to this:
Scientists propose a solution to a critical barrier to producing fusion
Physicists have discovered a possible solution to a mystery that has long baffled researchers working to harness fusion. If confirmed by experiment, the finding could help scientists eliminate a major impediment to the development of fusion as a clean and abundant source of energy for producing electric power.

An in-depth analysis by scientists from the U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) zeroed in on tiny, bubble-like islands that appear in the hot, charged gases — or plasmas — during experiments. These minute islands collect impurities that cool the plasma. And it is these islands, the scientists report in the April 20 issue of Physical Review Letters, that are at the root of a long-standing problem known as the “density limit” that can prevent fusion reactors from operating at maximum efficiency.

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Is this the breakthrough?  Even if it is, there will need to be decades of development before we can keep our modern world running this way.  But even so, one small step ...

Physicists being physicists.