Questions tagged [reversible-computing]
The reversible-computing tag has no usage guidance.
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Can reversible computers really perform truly reversible computations in practice?
Someone once told me that with reversible computers there is no energy cost for the computation itself, there is only a cost for running the hardware. But is this true in practice, or is it only an ...
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Reversible computing as a path to a useful PRNG or hash function?
There's a question I've long had about reversible computing: do non-trivial algorithms usually end up generating strongly pseudorandom data as an artifact of the computation?
The most straightforward ...
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Are there any formal systems or programming languages in which its only possible to define functions that have inverses?
Consider an algorithm $f(x)$.
Are there formal systems or programming languages that only allow $f(x)$ to be defined if $f^-1(x)$ exists?
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How does the circuit depth of a bijective function change if it is optimally rexpressed in terms of larger gates?
Consider a bijective function $f:\{0,1\}^n\rightarrow \{0,1\}^n$. Let $d_k$ be the minimal circuit depth of $f$ when expressed in terms of arbitrary $k$ bit gates (i.e. arbitrary bijective functions ...
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Would all objects in a reversible computing language be mutable?
Full disclosure, I'm asking this after watching a couple pop science videos; I do not know anything about the actual physics and hardware. I suspect the presenters expected an audience like me because ...
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Is this statistical group summation unambiguously reversible?
Let $X$ be a finite multisubset of $\mathbb{N}^2$. Let's introduce the following notation:
$A$ is a set of all first elements of pairs from $X$ and $B$ is a set of all second elements of pairs from $X$...
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Why isn't energy wasted with reversible computing? Isn't information discarded when we feed the function with a new input?
I understand that irreversible computing consumes energy because it has to "get rid" of outputs which have been used. With reversible computing that information is not "wasted" because with the ...
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How to Implement a reversible OR operator with a Fredkin gate (controlled swap)?
How to implement a reversible OR operator with a Fredkin gate ?
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What is the relation between reversible circuits and invertible functions?
A reversible circuit, if I understand it correctly, is a circuit where every gate in the circuit is invertible, i.e. can simply be “turned in the opposite direction”, so that the entire circuit can in ...
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How Janus (Reversible Programming Language) `if`, `while`, and Update Work
In Reversible Computing, all program statements are reversible. I understand for example that the following:
\begin{align}
x\ {+}&{=}\ 4\\
y\ {*}&{=}\ x\\
x\ {-}&{=}\ 10
\end{align}
Has ...
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Reversible computation and no cloning theorem in quantum computing
I am having a problem in understanding a conflict between reversibility in quantum computation and the No cloning theorem. Given a function f, we construct the reversible version of f by adding ...
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How to prove Landauer's principle [closed]
I have some questions about energy emitted when one bit of information is processed.
Landauer's principle states the minimum possible amount of energy required to erase one bit of information is <...
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How to model reversible interactive programs
Reversible programs with finite execution steps are well studied. For example, a Turing machine whose transitions are reversible and halts can be executed backwards consuming its tape in the reverse ...
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Is it possible to make N-way Controlled-NOTs out of Toffoli gates, without extra work bits?
I'm working on exercise 4.29 of Nielsen and Chuang:
Find a circuit containing O(n^2) Toffoli, CNOT, and single qubit gates which implements a $C^n(X)$ gate (for n >3), using no work qubits.
As ...
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What difference does it make when universal classical gates in quantum computation are reversible but not unitary?
As I've come across Grovers algorithm I dont understand why when computing F(X), which is an oracle function people use classical reversible circuits(toffoli, fredkin) to evaluate the circuit. Why can'...
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What's flawed about the "save-the-input" method of reversible computing?
I'm an undergraduate just beginning to read about reversible computing. I know that, because of Landauer's principle, irreversible computations dissipate heat (and reversible ones do not). I brought ...
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A programming language that can only implement computable bijective functions?
Are there programming languages(or logic) that can implement(or express) a function $f:\mathbb{N}\to \mathbb{N}$ if and only if $f$ is a computable bijective functions?
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