This paper is devoted to a continuation of the author's research that was published in
[1]; the subject is the study of the elementary Lie algebra of linear operators {A1, A2} in a Hilbert space H with the property that [A~., All = iA1.It is convenient to study the algebra {A1, A2} by using the Lie group of affine transformations of the line
[3], whose Lie algebra of vector fields satisfies the same commutator relation. We limit ourselves to operators At and A2 for which the following assumptions are satisfied: a) A1 is a dissipative densely defined operator with the same defect spaces E = E+, (dim E = r < oo); b) A2 is bounded and (A2)IH C_ E, (At = (A -A*)/2i).
The fundamental result of the the paper is that the Lie algebra {At, A2} can be realized in some space of meromorphic functions on a Riemann surface Q, and here one of the operators will be a multiplication by a meromorphic function f(P) -+ A(P)f(P), P 9 Q, while the second will be a translation operator, f(P) -+ f(a(P)), where a is an automorphism of the Riemann surface Q, (a 2 = 1, P 9 Q).
1.