What does semi-decidable mean?
To say that a language L is semi-decidable means that there is an algorithm that accepts precisely the strings in L; however, for a string x /∈ L, the algorithm will either reject or not halt. In order for this intuition to be valid, we have to accept the Church-Turing Thesis.
What is computability and Decidability?
Computability: determining if a problem can be solved in. finite time. Computabile ≡ Decidable in case of binary problems (i.e, with. a yes/no answer)
What is partially decidable?
Partially decidable or Semi-Decidable Language -– A decision problem P is said to be semi-decidable (i.e., have a semi-algorithm) if the language L of all yes instances to P is RE. A language ‘L’ is partially decidable if ‘L’ is a RE but not REC language.
What is the difference between completeness and Decidability?
Completeness means that either a proof or disproof exists. Decidability means that there’s an algorithm for finding a proof or disproof. In nice cases, they are equivalent, since in a complete theory, you can just iterate over every possible proof until you find one that either proves or disproves the statement.
What is decidability and Undecidability?
A language is called Decidable or Recursive if there is a Turing machine which accepts and halts on every input string w. Every decidable language is Turing-Acceptable. A decision problem P is decidable if the language L of all yes instances to P is decidable.
What do you mean by decidability?
: capable of being decided specifically : capable of being decided as following or not following from the axioms of a logical system Was logic complete …? And was it decidable, in the sense that there was a method that demonstrated the truth or falsity of every statement? —
What is Decidability in flat?
A language is called Decidable or Recursive if there is a Turing machine which accepts and halts on every input string w. A decision problem P is decidable if the language L of all yes instances to P is decidable.
What is the difference between decidable and computable?
As adjectives the difference between computable and decidable. is that computable is capable of being computed while decidable is capable of being decided.
Which among the following are semi decidable?
Discussion Forum
Que. | Which among the following are semi decidable? |
---|---|
b. | Rec-NFA |
c. | Infinite-DFA |
d. | All of the mentioned |
Answer:All of the mentioned |
Does decidability imply completeness?
So clearly, decidability implies completeness. But completeness should also imply decidability since by enumerating all proofs, you’re bound to eventually find one, and enumerating all proofs is computationally easy.
Why is decidability important?
It’s the introduction of new methods and new questions into mathematics that was important. Decidability is important in the context of computation – when one can think that time has been introduced into logic – one obviously wants an answer to a question in a finite amount of time.