Can a Turing Machine Execute Multiple Programs?

[samaaa]

Hi:
I read many articles about turing machine,but i still confused

is a turing machine can only execute one program(hardwired) ?
or it can execute many programs(like a conventional computer)?

i asking about turing machine as shown in figure blew(not asking about universal TM ):
http://s24.postimg.org/52paaxm85/21949732.png

 

[Bill Simpson]

Delta (item 4) is sometimes called the "table."
That is equivalent to a program you would write for a computer.

I don't remember distinguishing "input symbols" from "tape symbols."
The tape is equivalent to the input and output for a computer.

So you could write any "program" and fill the table, which is you defining delta.
That program could then accept any input on the tape and produce the output on the tape.

Does that help?

 

[samaaa]

Delta (item 4) is sometimes called the "table."
That is equivalent to a program you would write for a computer.

I don't remember distinguishing "input symbols" from "tape symbols."
The tape is equivalent to the input and output for a computer.

So you could write any "program" and fill the table, which is you defining delta.
That program could then accept any input on the tape and produce the output on the tape.

Does that help?

yes that help,
but if the turing machine can execute any "program",
that mean it can simulate any other turing machine ,
so that mean any turing machine we can called it universal turing machine!

 

[samaaa]

I read information said that:
the turing machine can only execute one program
the universal turing machine is Re-programmable machine

the information here:
http://www.cs.rpi.edu/~moorthy/Courses/modcomp/slides/Universal_Turing.ppt

 

[D H]

yes that help,
but if the turing machine can execute any "program",
that mean it can simulate any other turing machine ,
so that mean any turing machine we can called it universal turing machine!

A Turing machine is not necessarily able to execute any "program". What if the table (δ) is hard-wired? That one program can be swapped out for another is the key distinguishing feature between a universal Turing machine and a plain ordinary Turing machine.

 

[samaaa]

A Turing machine is not necessarily able to execute any "program". What if the table (δ) is hard-wired? That one program can be swapped out for another is the key distinguishing feature between a universal Turing machine and a plain ordinary Turing machine.

that help,thank you