Problem Detail: A quantum computer can possibly calcluate computable functions faster, but it can’t calculate functions which a normal computer can’t calculate? If a function is not computable? Does this mean it will never be computable? Even if we change the Read More …
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[Solved]: Would it ever be possible for computer viruses to evolve new “genes” to allow them to perform their job?
Problem Detail: As an A-level Biology student, I have thought a lot about the links with Biology and Computer Science, and something that often comes to mind are the links between Immunology and Computer Security/Viruses. For example, I (through reading about Read More …
[Solved]: Is there a difference between $lambda xy.xy$ and $lambda x.lambda y.xy$?
Problem Detail: I am currently learning the lambda calculus and was wondering about the following two different kinds of writing a lambda term. $lambda xy.xy$ $lambda x.lambda y.xy$ Is there any difference in meaning or the way you apply beta reduction, Read More …
[Solved]: Corresponding noun for “side-effect-free”?
Problem Detail: For functions or computations we have terms like: Deterministic – Determinism Pure – Purity Now what is the correct corresponding noun for side-effect-free? “Side-effect freeness”? “Side-effect freedom”? “Non-side-effective”? Asked By : rolve Answered By : David Richerby A good rule of Read More …
[Solved]: Visualizing a Non Deterministic Decider
Problem Detail: I know that we can visualize a Non deterministic TM as a TM which splits into multiple copies of itself whenever it sees a non deterministic path (Yes, I also know that this is just a visualization and is Read More …
[Solved]: Does a context-free grammar with multiple variables have a “starting” point?
Problem Detail: So lets consider the following grammar $$ begin{align*} S &to 0 mid 0A A &to 1 end{align*} $$ would the string “1” be accepted by the language or must the language start with $S$? Asked By : Moddah Answered By Read More …
[Solved]: Linear time labeling algorithm for a tree?
Problem Detail: I have an undirected tree whose vertices I want to label. The leaf nodes should be labeled one. Then, assume the leaves were removed. In the tree that remains, the leaves should be labeled two. This process continues in Read More …
[Solved]: The language of machines that accepts all palindromes is not Turing recognizable
Problem Detail: I have this question: $L = {langle M rangle | M$ is TM that accepts every palindrome over its alphabet $}$ Proof that $L$ is not Turing-recognizable by showing reduction from other non Turing-recognizable language. What I have tried Read More …
[Solved]: How to calculate the size of a page in a two level paging CPU?
Problem Detail: I am having difficulties with understanding the concept of paging. As a result I’ve got no idea how I can solve the following exercise – I’m lacking one more equation to solve it. I’ve read a lot about paging Read More …
[Solved]: Is $A$ regular if $A^{2}$ is regular?
Problem Detail: If $A^2$ is regular, does it follow that $A$ is regular? My attempt on a proof: Yes, for contradiction assume that $A$ is not regular. Then $A^2 = A cdot A$. Since concatenation of two non-regular language is not Read More …
