Multiples of integers

From timescalewiki
Revision as of 06:21, 19 October 2014 by Tom (talk | contribs)
Jump to: navigation, search

The set $h\mathbb{Z}=\{\ldots,-2h,-h,0,h,2h,\ldots\}$ of multiples of the integers is a time scale.

$\mathbb{T}=h\mathbb{Z}$
Generic element $t\in \mathbb{T}$: For some $n \in \mathbb{Z}, t =hn$
Jump operator: $\sigma(t)=t+h$
Graininess operator: $\mu(t)=h$
$\Delta$-derivative: $f^{\Delta}(t)=\dfrac{f(t+h)-f(t)}{h}$
$\Delta$-integral: $\displaystyle\int_s^t f(\tau) \Delta \tau = \displaystyle\sum_{k=\frac{s}{h}}^{\frac{t}{h}-1} hf(hk)$
Exponential function: $\begin{array}{ll} e_p(t,s) &= \exp \left( \displaystyle\int_{s}^{t} \dfrac{1}{\mu(\tau)} \log(1 + hp(\tau)) \Delta \tau \right) \\ &= \exp \left( \displaystyle\sum_{k=\frac{s}{h}}^{\frac{t}{h}-1} \log(1+hp(hk)) \right) \\ &= \displaystyle\prod_{k=\frac{s}{h}}^{\frac{t}{h}-1} \left( 1+hp(hk) \right) \\ \end{array}$
Hilger circle: Hilgercircle,T=hZ.png
Gamma function: $\Gamma_{h\mathbb{Z}}(t;s)=h\displaystyle\sum_{k=0}^{\infty} \left( \displaystyle\prod_{j=s}^{k-1} \dfrac{j+x}{j+1} \right) \dfrac{1}{(1+h)^{k+1}}.$