Why is "as well" used here?

Question

(Note: I'm reading a sentence from a computer science book pdf Introduction to Automata Theory, Languages, and Computation.)

I'm confused by the following sentence when the phrase "as well" appears:

Of the eight states in Fig. 2.13, starting in the start state B, we can only reach states B, E, and F. The other five states are inaccessible from the start state and may as well not be there.

I interpret "as well" as "also", so I think it would not be necessary. Since in the sentence I quoted, there is no mention that some states are not there before the phrase "as well" appears. Could I remove "as well" like the following to mean the same thing?

[...] and may not be there.

Now I suspect that it would mean "therefore" instead. Could anyone please correct me?

Answer 1

"may as well" is a set phrase. It's explained in Merriam-Webster:

used to say that something else could have been done with the same result

So the state machine described in the book would act the same if the other states were not included.

This isn't the same as "may not", which means that it's possible that something doesn't exist or doesn't happen. That's clearly not true, because those states are in the diagram. They're just not used for anything.

Answer 2

Dictionary.com has an example for as well:

With an equal or similar result, as in Since he can't get there in time, he might as well stay at home.

The OP’s example

The other five states are inaccessible from the start state and may as well not be there.

means

... and are as good as not being there.

Answer 3

'as well' implies 'as well/much (as sth)'

Look below.

He can speak English as much (as I can speak English).

I can speak English. He can speak English as well (as I) (=in addion to I)

'as well' essentially has at least one implicit or explict "thing" that is functioning as its counter partner.

The other five states are inaccessible from the start state and may as well not be there.

means

may not be there as much (as the other five states are inaccessible from the start state=x), which means

It's natural that x may not be there. In short, "may 'naturally' not be there."