Exam 12: Models of Computation

A tape is used to hold the ____ to the Turing machine.

In any collection of Turing machine instructions, there can be two different instructions that both begin with the same current state and current symbol.

A Turing machine includes a(n) tape that extends infinitely in both directions._________________________

Discuss at length the assertion that Turing machines define the limits of computability.

The model of a phenomenon must capture the full functionality of the real thing.

Turing machines define the limits of ____, which is what can be done by symbol manipulation algorithms.

Unsolvable problems related to the halting problem have the following practical consequence: ____.

A computing agent must be able to act in accordance with ____________________ instructions.

The Turing machine must execute instructions in the order that the instructions are numbered.

The ____ thesis can never be proved because the definition of an algorithm is descriptive, not mathematical.

List three practical consequences arising from unsolvable programs related to the halting problem.

In binary representation, any unsigned whole number n is encoded by a sequence of n + 1 1s._________________________

A Turing machine cannot produce output.

A(n) ____ is a statement advanced for consideration and maintained by argument.

Explain how a Turing machine differs in scale from any real computing agent.

Although we can compare two Turing machine algorithms for the same task, we can't really compare the efficiency of a Turing machine algorithm with an algorithm that runs on a "real" computer.

Each time a Turing machine operation is done, four actions take place._________________________

In a state diagram, ____ are used to represent states.

It is important to note that unsolvable problems related to the halting problem are unsolvable because of their ____.

A(n) ____ is a visual representation of a Turing machine algorithm.