Definition:Absolute Value of Cut

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Definition

Let $\alpha$ be a cut.


The absolute value of $\alpha$ is denoted and defined as:

$\size \alpha = \begin {cases} \alpha & : \alpha \ge 0^* \\ -\alpha & : \alpha < 0^* \end {cases}$

where:

$0^*$ denotes the rational cut associated with the (rational) number $0$
$\ge$ denotes the ordering on cuts.


Sources