• Korean Journal of Mathematics
• /
• v.21 no.3
• /
• pp.285-292
• /
• 2013

B. C. Berndt computed the Fourier series of a class of generalized Eisenstein series, which gives an analytic continuation to the generalized Eisenstein series. In this paper, continuing his work, we consider generalized non-holomorphic Eisenstein series and give an analytic continuation to the $s$-plane.

• Honam Mathematical Journal
• /
• v.36 no.4
• /
• pp.895-899
• /
• 2014

In this paper, we consider generalized two variable Eisenstein series. We give analytic continuation and prove modular transformation formulae for them.

• Journal of the Korean Mathematical Society
• /
• v.59 no.6
• /
• pp.1171-1184
• /
• 2022

We study the real-analytic continuation of local real-analytic solutions to the Cauchy problems of quasi-linear partial differential equations of first order for a scalar function. By making use of the first integrals of the characteristic vector field and the implicit function theorem we determine the maximal domain of the analytic extension of a local solution as a single-valued function. We present some examples including the scalar conservation laws that admit global first integrals so that our method is applicable.

• Bulletin of the Korean Mathematical Society
• /
• v.46 no.6
• /
• pp.1099-1133
• /
• 2009

We study the hyperbolic cosine and sine laws in the extended hyperbolic space which contains hyperbolic space as a subset and is an analytic continuation of the hyperbolic space. And we also study the spherical cosine and sine laws in the extended de Sitter space which contains de Sitter space S$^n_1$ as a subset and is also an analytic continuation of de Sitter space. In fact, the extended hyperbolic space and extended de Sitter space are the same space only differ by -1 multiple in the metric. Hence these two extended spaces clearly show and apparently explain that why many corresponding formulas in hyperbolic and spherical space are very similar each other. From these extended trigonometry laws, we can give a coherent and geometrically simple explanation for the various relations between the lengths and angles of hyperbolic polygons, and relations on de Sitter polygons which lie on S$^2_1$, and tangent laws for various polyhedra.

• Journal of the Korean Mathematical Society
• /
• v.43 no.6
• /
• pp.1143-1158
• /
• 2006

We consider the projectivization of Minkowski space with the analytic continuation of the hyperbolic metric and call this an extended hyperbolic space. We can measure the volume of a domain lying across the boundary of the hyperbolic space using an analytic continuation argument. In this paper we show this method can be further generalized to find the volume of a domain with smooth boundary with suitable regularity in dimension 2 and 3. We also discuss that this volume is invariant under the group of hyperbolic isometries and that this regularity condition is sharp.

• Bulletin of the Korean Mathematical Society
• /
• v.31 no.1
• /
• pp.55-60
• /
• 1994

It is well known that if P(x,D) is an elliptic differential operator, with real analytic coefficients, and P(x,D)u = 0 in an open, connected subset .ohm..mem.R$^{n}$ , then u is real analytic in .ohm. Hence, if there exists x$_{0}$ .mem..ohm. such that u vanishes of .inf. order at x$_{0}$ , u must be identically 0. If a differential operator P(x, D) has the above property, we say that p(x,D) has the strong unique continuation property (s.u.c.p.). If, on the other hand, P(x,D)u = 0 in .ohm., and u = 0 in .ohm.', an open subset of .ohm., implies that u = 0 in .ohm. we say that P(x,D)u = 0 in .ohm., and suppu .contnd. K .contnd. .ohm implies that u = 0 in .ohm. we sat that P(x,D) has the weak unique continuation property (m.u.c.p.).

• Communications of the Korean Mathematical Society
• /
• v.27 no.1
• /
• pp.107-116
• /
• 2012

Here, by using the symbolical method introduced by Burchnall and Chaundy, we aim at constructing certain expansion formulas for the generalized hypergeometric function $_pF_q$. In addition, using our expansion formulas for $_pF_q$, we present formulas of an analytic continuation of the Clausen hypergeometric function $_3F_2$, which are much simpler than an earlier known result. We also give some integral representations for $_3F_2$.

• East Asian mathematical journal
• /
• v.8 no.2
• /
• pp.235-240
• /
• 1992

• East Asian mathematical journal
• /
• v.11 no.2
• /
• pp.359-364
• /
• 1995

• East Asian mathematical journal
• /
• v.16 no.2
• /
• pp.331-337
• /
• 2000