We can write a decider for the language:
$E=\{A\; |\; A \mbox{ is a DFA and } L(A)=\emptyset\}$
by marking method.
Why we cannot use the same method to write a decider for the language with TM as follows?
$A = \{ M \;|\; M \mbox{ is a TM and } L(M)=\emptyset\}$
