Fungrim entry: 686ce0

\theta_{4}\!\left(2 z , 2 \tau\right) = \frac{\theta_{3}\!\left(z , \tau\right) \theta_{4}\!\left(z , \tau\right)}{\theta_{4}\!\left(0 , 2 \tau\right)}

Assumptions:

z \in \mathbb{C} \;\mathbin{\operatorname{and}}\; \tau \in \mathbb{H}

TeX:

\theta_{4}\!\left(2 z , 2 \tau\right) = \frac{\theta_{3}\!\left(z , \tau\right) \theta_{4}\!\left(z , \tau\right)}{\theta_{4}\!\left(0 , 2 \tau\right)}

z \in \mathbb{C} \;\mathbin{\operatorname{and}}\; \tau \in \mathbb{H}

Definitions:

Fungrim symbol	Notation	Short description
`JacobiTheta`	$\theta_{j}\!\left(z , \tau\right)$	Jacobi theta function
`CC`	$\mathbb{C}$	Complex numbers
`HH`	$\mathbb{H}$	Upper complex half-plane

Source code for this entry:

Entry(ID("686ce0"),
    Formula(Equal(JacobiTheta(4, Mul(2, z), Mul(2, tau)), Div(Mul(JacobiTheta(3, z, tau), JacobiTheta(4, z, tau)), JacobiTheta(4, 0, Mul(2, tau))))),
    Variables(z, tau),
    Assumptions(And(Element(z, CC), Element(tau, HH))))

Topics using this entry

Lattice transformations for Jacobi theta functions