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On May 2011, D-Wave Systems Inc. announced "D-Wave One", as "the world's first commercially available quantum computer". No wonder this adiabatic quantum computer based on 128-qubit chip-set provoked an immediate controversy. Over the last 40 years, quantum computation has been a very promising yet challenging research area, facing major difficulties producing a large scale quantum computer. Today, after Google has purchased "D-Wave Two" containing 512 qubits, criticism has only increased.

In this work, we examine the theory underlying the D-Wave, seeking to shed some light on this intriguing quantum computer. Starting from classical algorithms such as Metropolis algorithm, genetic algorithm (GA), hill climbing and simulated annealing, we continue to adiabatic computation and quantum annealing towards better understanding of the D-Wave mechanism.

Finally, we outline some applications within the fields of information and image processing. In addition, we suggest a few related theoretical ideas and hypotheses.

We calculate the annihilation decay rates of the ${}^3{D}_2(2^{--})$ and ${}^3{D}_3(3^{--})$ charmonia and bottomonia by using the instantaneous Bethe–Salpeter (BS) method. The wave functions of states with quantum numbers $J^{PC}=2^{--}$ and $3^{--}$ are constructed. By solving the corresponding instantaneous BS equations, we obtain the mass spectra and wave functions of the quarkonia. The annihilation amplitude is written within Mandelstam formalism and the relativistic corrections are taken into account properly. This is important, especially for high excited states, since their relativistic corrections are large. The results for the $3g$ channel are as follows: ${\mathrm{\Gamma }}_{1^3{D}_2(c\bar{c})\to ggg}=9.24$ keV, ${\mathrm{\Gamma }}_{1^3{D}_3(c\bar{c})\to ggg}=25.0$ keV, ${\mathrm{\Gamma }}_{1^3{D}_2(b\bar{b})\to ggg}=1.87$ keV and ${\mathrm{\Gamma }}_{1^3{D}_3(b\bar{b})\to ggg}=0.815$ keV.