I have a script that takes a while to simulate. I can modify it in such a way where I can use fewer qubits at a time, but it will require more iterations of manipulation. I believe this will cut down on simulation time, but does is it worse when running on an actual quantum computer? It will still run in polynomial time, regardless.

I am thinking I should go with the fewer qubits and more gates method, since I would free up qubits for others and cut my simulation time, but I would like to know which is technically the better way, computationally.


closed as too broad by Niel de Beaudrap, MEE the setup wizard, Sanchayan Dutta, DaftWullie Nov 13 '18 at 21:57

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ this is probably very hardware dependant, and therefore difficult to give a proper answer to. The space/time trade-off for noise might vary significantly. $\endgroup$ – DaftWullie Nov 7 '18 at 13:51
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    $\begingroup$ Not only is it hardware dependent, it depends on whether the number of gates brings you close to the coherence times of the qubits in the particular platform or not; and on whether the number of qubits you require is close to the maximum available or not. Even a small constant factor (e.g. 3/2) can be significant for either one, if you are close to the limits of what the device can do. $\endgroup$ – Niel de Beaudrap Nov 7 '18 at 14:12
  • $\begingroup$ There can be multiple people answering with each person giving the description for their chosen hardware/noise setup. So I don't think of this as worth flagging unclear. $\endgroup$ – AHusain Nov 7 '18 at 14:13
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    $\begingroup$ @AHusain: See my comment above, it depends on what the user is trying to realise as well. It's a very broad question. $\endgroup$ – Niel de Beaudrap Nov 8 '18 at 11:52