On the paper "Quantum Computing Hamiltonian cycles" The paper Quantum Computing Hamiltonian cycles claims:

An algorithm for quantum computing Hamiltonian cycles of simple,
cubic, bipartite graphs is discussed. It is shown that it is possible to
evolve a quantum computer into an entanglement of states which map
onto the set of all possible paths initiating from a chosen vertex, and
furthermore to subsequently project out all states not corresponding to
Hamiltonian cycles.

The algorithm requires polynomial in $n$ qubits and gives
example with a quantum &quot;gadget&quot;.
According to graphclasses
on bipartite ∩ maximum degree 3 graphs hamiltonian cycle is NP-complete.
cstheory claims

Several hard graph problems remain hard on planar cubic bipartite graphs. They include Hamiltonian cycle problem

Since cubic planar bipartite graphs are subset of cubic bipartite
graphs, hamiltonicity of cubic bipartite graphs must be NP-hard too.
Doesn't the above arguments show that quantum computer can solve
NP-complete problem, including SAT, which appears to be open problem?
Can the paper be extended to other subclasses of graphs for which
hamiltonicity is NP-hard?
Bugs me the date of the paper is 29th February 1995 and this date
doesn't exist, since odd year can't be leap year.
I emailed the author.
He replied &quot;yes that paper is wrong!&quot;.
He has lost the passwords to remove it from the web.