Could you please give a direction/reference towards realising the following using any set of realisable quantum gates

$$\boxed{|S_{n}\rangle = \frac{1} {\sqrt{n!}} \sum_{S\in P_n^{n}} ( \,-1) \,^{\Gamma(S)}|s_{0}\rangle |s_{1}\rangle ....|s_{n-1}\rangle}$$

Here $P_n^{n}$ is the set of all permutations of $Z_n := \{0,1,··· ,n−1\}$, $S$ is a permutation (or sequence) in the form $S = s_0 s_1 ···s_{n−1}$. $\Gamma(S)$, named inverse number, is defined as the number of transpositions of pairs of elements of $S$ that must be composed to place the elements in canonical order, $012 · · · n−1$.

  • $\begingroup$ It is an interesting question. May I ask what does the state represent? $\endgroup$ Dec 1, 2019 at 7:20
  • $\begingroup$ @MartinVesely The state enumerates all permutations of $Z_{n}$. I don't know the significance of inverse number here. $\endgroup$
    – qcnoob
    Dec 1, 2019 at 9:30
  • $\begingroup$ related: quantumcomputing.stackexchange.com/q/8976/55, quantumcomputing.stackexchange.com/q/9022/55 $\endgroup$
    – glS
    Dec 2, 2019 at 11:54
  • $\begingroup$ just want to point out that "any set of realisable quantum gates" is not a sensible requirement, otherwise I can just answer this by saying "use any gate that sends $|0\cdots 0\rangle$ to $|S_n\rangle$", which is a realisable quantum gate (any gate is "realisable"). You are probably thinking of using as "realisable quantum gates" single-qubit gates and CNOTs, or something similar $\endgroup$
    – glS
    Dec 2, 2019 at 11:56
  • 1
    $\begingroup$ I just realised that this question is an exact duplicate of quantumcomputing.stackexchange.com/q/8668/55 $\endgroup$
    – glS
    Dec 2, 2019 at 15:07


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