Questions tagged [quantum-parallelism]

The idea that a quantum computer can simultaneously explore many possible solutions to a problem since quantum memory register can exist in a superposition of states, each component of this superposition may be thought of as a single argument to a function. A function performed on the register in a superposition of states is thus performed on each of the components of the superposition, but this function is only applied one time.

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When we say that 4 qubits can represent $2^4$ binary bit sequences, how do we iterate to the desired bit sequence?

Being new to QC, always heard that $n$ qubits can represent $2^n$ unique combinations of equivalent binary bits at the same time. We can also say that if we have $n$ data lines, we can pass $2^n$ ...
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Does quantum superposition allow to apply an algorithm to all bits possibly in one shot?

From what I understood, quantum programming can solve some algorithm exponentially faster. Thanks to the superposition, unlike a classic bit, which can be either 0 or 1, a qubit can be both 0 and 1. ...
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Are qubits just analog, continuous classical bits? [duplicate]

Topologically, classical bits (cbits) are essentially special cases of qubits restricted to the poles of the Bloch sphere. However, this restriction doesn't seem to be classical per se, but is simply ...
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How to order results after multi-circuit qiskit.execute parallel run?

I'm kinda new to qiskit and I find really fascinating its parallelization capabilities, then I'm trying to creating all the needed circuits for my application at once and transpile, assemble and ...
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Generalizing quantum parallelism to bits or qubits

On pg. 31 in Nielsen and Chuang, it's said that: This procedure can easily be generalized to functions on an arbitrary number of bits, by using a general operation known as the Hadamard transform, or ...
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Why does the output for $y$ have to be $y ⊕ f(x)$ in Quantum parallelism?

For the following Quantum parallelism algorithm: Why does the output for $y$ have to be $y ⊕ f(x)$ for the algorithm to work? Why can't it be anything else, such as $f(x)$ only or $f(y)$ etc?
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Intuition for why the normalization for states in quantum parallelism is the same

On page 31 of Quantum Computation and Quantum information by Nielsen and Chuang, it is said that: Consider the circuit shown in Figure 1.17, which applies $U_f$ to an input not in the computational ...
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Is it currently more cost effective/efficient to run a general purpose parallel algorithm on an accelerated quantum simulator or on CPUs?

Quantum simulation is advancing and I'm wondering if now or in the future there is a point where its more cost effective and efficient to run general purpose parallel algorithms (e.g. with a mix of ...
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Quantum parallelism and Deutsch's algorithm - what is $U_f$ really? [closed]

I'm trying to understand quantum parallelism ideas leading the Deutsch's algorithm. The circuit in question is I understand that we end up with $$|\psi_3 \rangle = \pm | f(0) \oplus f(1) \rangle \...
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How do qubits in quantum computers work? [closed]

I was reading about quantum computers and qubits. While a classical bit can be either 0 or 1, a qubit can be 0 or 1 or both at the same time (can it be none too?). But how is this useful at all? If it ...
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Splitting a quantum task between multiple devices

I've been wondering, are there any known tasks/algorithms that can be performed on 1 quantum device, but also be somehow modified and split between several smaller devices? The thought behind the idea,...
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How one would implement the circuit to create superpositions corresponding to efficiently integrable probability distributions?

See article here: https://arxiv.org/abs/quant-ph/0208112 There are two steps in this procedure that I am curious about. First off, they suppose one can construct a circuit which efficiently performs ...
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Is Deutsch 1985b wrong about and Quantum Parallelism?

"Quantum theory, the Church-Turing principle and the universal quantum computer" (Deutsch 1985b) appears to introduce the term of "quantum parallelism" (the term is not in "...
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Building a state with parallel execution

I'm trying to implement the main algorithm described in the Quantum Recommendation Systems paper. In order to do this, I have to create a quantum state $|x\rangle$ corresponding to a real vector ...
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Understanding Steps in Deutsch's Algorithm

I am currently working my way through the book Quantum Computation and Quantum Information by Chuang and Nielsen. So far it has been a joy to read, however I am hung up on a couple aspects of quantum ...
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Does the massive parallelization in Quantum computing imply parallelization of input (as opposed to Turing machine)?

Being a newbie in this field, I'm trying to understand what types of real-life workloads are suitable for migrating to Quantum computers. Intuitively, it seems to me that if a Quantum computer ingests ...
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Can quantum parallelism be turned on and off?

The qubit is able to take on multiple states at once, unlike the bit. This property I know is superposition, but is this property perpetual (always on) or optional (controlled to be on or off only ...
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Which algorithm in quantum computing can be implemented for a HPC system?

I am new to quantum computing and I wanted to do a project for one of my classes where I study a specific algorithm from the field and then insert parallelism in it so it can be executed more ...
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Is quantum parallel search impossible?

Scott Aaronson's blog notably states: Quantum computers would not solve hard search problems instantaneously by simply trying all the possible solutions at once. Is this a statement of a law, as ...
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Effects of quantum computing on parallel universes

I have heard a few times that one way of describing quantum computers is that they essentially use the computing power of their counterparts in alternate realities that they access through ...
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Can I imagine quantum computers as working via parallel computing?

Beginners question, so please stay on the beginner's level with possible answers. I know very well what a qubit, superposition, and entanglement is. Also, I am familiar with several physical ...
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Is the intuition of quantum parallelism always correct?

I recently read in Section 7.5.2 of Quantum Computing: A Gentle Introduction by Eleanor Rieffel and Wolfgang Polak a section in which they criticize the view of quantum parallelism in quantum ...
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How does quantum function parallelism work?

Quantum parallelism is usually introduced from CNOT schema, saying that there it results, calling $ |c\rangle $ the control and $|t\rangle$ the target $$ |0\rangle |t\rangle \implies |0\rangle |t\...
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What do "$i$-th basic network", "quantum multiplexers" and "quantum parallelism" mean in this context? How are they beneficial?

I have been reading the paper A quantum-implementable neural network model (Chen et al., 2017) for a few days now, but failed to understand how exactly their algorithm offers a speedup over the ...
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