Title: Two Dimensional Stringy Black Holes with One Asymptotically Flat Domain Show Chinese title

Title: 具有一个渐近平坦区域的二维弦黑洞

Abstract: The exact black hole solution of 2D closed string theory has, as any other maximally extended Schwarzschild-like geometry, two asymptotically flat spacetime domains. One can get rid of the second domain by gauging the discrete symmetry on the SL(2,R)/U(1) coset that interchanges the two asymptotic domains and preserves the Kruskal time orientation everywhere in the Kruskal plane. Here it is shown that upon performing this orbifold procedure, we obtain a theory of unoriented open and closed strings in a black hole background, with just one asymptotically flat domain and a time-like orbifold singularity at the origin. All of the open string states of the model are confined to the orbifold singularity. We also discuss various physical aspects of the truncated black hole, in particular its target duality -- the model is dual to a conventional open string theory in the black hole geometry. Show Chinese abstract

Abstract: 二维闭弦理论的精确黑洞解和其他极大延展的Schwarzschild类几何一样，具有两个渐近平直时空区域。通过规范SL(2,R)/U(1)余空间中的离散对称性（该对称性交换了这两个渐近区域，并在整个Kruskal平面中保持Kruskal时间定向），可以消除第二个区域。这里表明，在执行这种轨道构造后，我们得到一个在黑洞背景下具有无定向开弦和闭弦的理论，其中只有一个渐近平直区域以及在原点处的时间轨道奇异性。模型的所有开弦态都被限制在轨道奇异性上。我们还讨论了截断黑洞的各种物理特性，特别是其目标对偶性——该模型在黑洞几何中与常规开弦理论是对偶的。