How to know one's way around for PhD in Covid times
I'd like to continue my formation with a PhD after my thesis.
You should have told us why. Think over it. Be ready to answer that question. Only go for a PhD if you can tell why. If you find your own answer convincing.
consider the idea of going someplace...
Excellent. Go to some place where research is decently funded, and where corruption is low. An easy measure for corruption is in the faculty's CVs: did they come from outside, or have they been promoted in-house?
even in the subfield of high energy theoretical physics
Don't choose the prefered subfield of some of the brightest minds, except if you are so brilliant that you can reasonably hope to make some difference in that field. Rather be the clever guy in a down-to-earth subfield. There are fascinating research questions everywhere. Lots of engineering is built on wild heuristics that is waiting for solid physical foundations. In condensed-matter physics, given the incredible variety of material structures, there are much more challenging questions than in theoretical HEP, and much less theoretists per question.
How should one approach this problem in Covid times?
Yes, times are hard. But I see there also a little advantage for your remote applications: as these days everybody has to use electronic means of communication, this brings you in one line with local candidates.
Is it common to ask &quot;what are your researchers doing&quot; in an email?
To whom would you write that mail? Wouldn't they get the impression that you haven't done your homework?
Is there an online list of who is doing what
Of course you can start from faculty lists, then proceed to their CVs and publication lists. But as you are not yet decided geographically, it's better you scan recent editions of high-level research journals, and look for work that is really impressing you. Then contact the authors.
in what university?
In many places, universities are second-tier. Don't overlook the well funded national laboratories and other research institutes outside the university system.