As per requested, here are the logical and scientific arguments that disprove the monotheist God's existence. Let me note that these arguments aren't necessary because the Theist has the burden of proof for their claim, whereas Atheists aren't required to disprove anything.
I am going by this definition from the Stanford Encyclopedia of Philosophy: "Theists believe that reality's ultimate principle is God—an omnipotent, omniscient, goodness that is the creative ground of everything other than itself." -
Monotheism (Stanford Encyclopedia of Philosophy)
And to those who believe in some sort of impersonal God or spiritual force, then these arguments don't apply. Though, I really don't think an impersonal force can be considered "God" because "God" is a personification. Also, if you feel that this God or force plays a role in your life, you pray to it, or it intervenes, then your God is actually a personal God.
If you believe in a God that is unknowable or beyond human comprehension, then your position is ultimately meaningless because you are asserting a concept that we can know nothing about and thus cannot derive meaning from this unknowable concept.
Now, on to the arguments: