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After reading some with regard to the quantum computing gates and the comparison to classic gates it seems that the quantum computer, at least for the time being, is not viewed as a programmable element of a "hardware circuit" but more as a hardware device that combines functions, as in what is termed in "classical computing" ASSP - application-specific signal processors. Is this view right?

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    $\begingroup$ No, it's not. The analogy doesn't make much sense (not to mention, sounds a lot like corporate buzzword to promote quantum computing) and isn't useful if you wish to learn the subject. In general, it's not a good idea to pull random concepts from classical computing and try to compare them with quantum computing, with the hope that something will stick. Quantum computing is a very different paradigm of computing as compared to classical computing (albeit, some concepts are similar); it's advisable to treat it as such. $\endgroup$ – Sanchayan Dutta Nov 28 '19 at 3:56
  • $\begingroup$ @Sanchayan From ALL the material that I seen that goes into details of algorithms, you structure an array of gates where data flows from the input through the gates (clearly in a very limited way when compared to the state of the art of classical computing systems) to produce outputs of usually one is selected (at least from the examples I seen). $\endgroup$ – Moti Nov 28 '19 at 7:00
  • $\begingroup$ what's the connection between the title and the body of the question? $\endgroup$ – glS Nov 28 '19 at 12:13
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Today many people believe that programming means coding on some language like python; this is not true. The early classical computers were programmed by inserting junctions which connect logical elements of an electronic scheme, and this is also programming.

I believe modern programmable quantum computers are programmed like that: a programmer is given a certain number of gates, and allowed ways to connect the gates; his task is to connect the gates to implement some algorithm.

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    $\begingroup$ Quantum gates are more like a sequence of laser or microwave pulses applied on qubits (say, in ion trap / superconducting architectures). Programming the gates would imply manipulating the sequence of the lasers. $\endgroup$ – Sanchayan Dutta Nov 28 '19 at 9:49
  • $\begingroup$ It seems that the REVERSIBILITY feature of the technology allows for "programing" - as you do with what is called FPGAs in the utilization of silicon technology. It will be nice to have a PROGRAMMABLE QC in the sense of legacy computing systems - but may be we are 30-40 years away before we derive a QC on chip:) $\endgroup$ – Moti Nov 28 '19 at 18:56
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(...) depending on what you attempt to compute you "design" your circuit - this is what is called ASSP (Application Specific Signal Processor) where the input is Signal which are processed by the Circuit (processor) to create the processed output - the measure gate. [Source]

Reading the question more carefully and after your clarification in the comments, I think it has some merit. It is indeed the case that quantum gates are not fully programmable in most architectures; the gate array (quantum circuit) has to be designed according to the specific algorithm and specific problem we're trying to solve (what you call ASSP), which certainly is a nuisance.

However, note that in Google's latest architectures like the Sycamore, the gates are indeed fully programmable (at least, that's their claim), as is expected of a general-purpose quantum computer. I'm not sure what your impression of "programming" quantum gates is, but it's like manipulating a sequence of laser or microwave pulses on qubits in ion-trap and superconducting architectures respectively. See Peter Shor's answer for a nice explanation.

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