The Spectral Hermitian Surface $(\Bbb C^\times, g_{\infty})$ as an Avatar of a Modular Surface

Consider $\mathcal F=\lbrace \mathcal L_t=(\Bbb C^{\times},g_t(s)) \rbrace_{t\in\Bbb R_{\gt 0}}$ where $g_t(s)=\vert F_t(s) \vert^2ds\otimes d\bar{s}$ and


$$F_t(s)=\int_{(0,1)} e^{t^2/\log x} \cdot x^{s-1}dx= 2\sqrt{\frac{t^2}{s}}K_1(2\sqrt{t^2s}). $$


For $K_1$ the modified bessel function of the second kind.


Looking at Bessel asymptotics we know that as $s\to 0$, $g_t(s)\sim \frac{1}{|s|^2}ds\otimes d\bar{s}$ (conical) and as $s\to\infty$, $g_t(s)\sim e^{-4\sqrt{t^2s}}ds\otimes d\bar{s}$ (collapsing end), and these asymptotics hold for the later defined $g_{\infty}(s).$ 


Define a trace over $F_t$


$$\mathcal M(s)=\sum_{t=1}^\infty F_t(s)$$


then the following identity is satisfied  


$$\frac{1+2\mathcal M(s)}{1+2\mathcal M(1/s)}= s^{\alpha}$$


where $\alpha$ is the weight. The proof that there exists some $\alpha \in \Bbb R$ such that the identity holds for all $s$ uses Poisson summation. 


Define a new metric which encodes the cumulative effect of the metrics on each of the surfaces $\mathcal L_t$ into one


$$g_{\infty}(s)=:\vert \Phi(s) \vert^2ds\otimes d\bar{s}$$


where we have


$$\Phi(s)=1+2\mathcal M(s)$$ then 


$$\Phi(1/s)= s^{\alpha} \Phi(s)$$


and so if we define the Hermitian metric using


$$h(s)=\vert \Phi(s) \vert^2$$


then


$$g_{\infty}(s)=h(s) \cdot ds \otimes d\bar{s}$$


which transforms like


$$g_{\infty}(1/s)= \vert s \vert^{2(\alpha-2)} \cdot g_{\infty}(s)$$


So we have the conformal Hermitian surface $(\Bbb C^\times,g_{\infty})$ whose metric transforms under  $s\mapsto  1/s$ with a modular type scaling factor. 


Due to the asymptotics of the metric, this surface has an infinite cusp as $s\to\infty$ and expands outward as $s\to 0$ but not as a surface of revolution - the expansion is anisotropic. So the surface is like a warped cylinder that pinches in one direction and expands anisotropically in the other.

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  2. You should figure out a way for your latex code to display properly. Formatting issues will push people away interested in engaging with your work. Also prioritize on learning proof writing as these ideas are interesting but lack proper rigor!

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