According to the Halakhah, does stating that HaShem does not exist constitute a curse or a profanation of God's name?

Question

I am an Italian ben Noach.

According to Rambam (Mishneh Torah-Avodat Kokhavim 2: 7;Hilchot Melachim 9:3):

• a Jew commits the crime of blasphemy if he curses HaShem using God's unique name or one of his names that cannot be canceled;

• a non-Jew commits the same crime whether he uses God's unique name or one of His other names, in any language.

However, I do not understand whether, for the Halakhah, the curse of God's name also includes the simple affirmation that He does not exist (that is, a purely atheistic profession).

How is this case legally framed? Rambam specifies (Mishneh Torah-Hilchot Teshuvah 3: 7) that the atheist, both Jewish and Gentile, is excluded from the world to come, but is the aforementioned claim punishable by an earthly court?

Also Rambam, in the fifth chapter of Mishneh Torah-Yesodei haTorah, describes the mitzvah of sanctifying the great name of the Almighty, deriving from Leviticus 22:32; however,provided that the precept applies only to Jews and is not part of the Noahide Law , from reading Rambam's words it is not clear to me whether a simple atheistic public declaration violates this mitzvah, and in any case I do not understand whether, even if it violates it, lashes are foreseen or not

Answer 1

Emphatic no. The Biblical-level cursing we are discussing involves wishing that God attack someone. See more here:

https://judaism.stackexchange.com/a/31898/21

Answer 2

the curse of G-d's name also includes the simple affirmation that He does not exist

The Rambam himself writes in his Hilchos Yesodei HaTorah (Foundations of the Torah, chapter 1):

The foundation of foundations and firmest pillar of all wisdom is, To know that there is a First Being, that He caused all beings to be, and that all beings from heaven and earth, and from between them, could not be save for the truth of His Own Being.

The 9th mitzvah is that we are commanded to sanctify G-ds name, as the Sefer HaMitzvot explains:

This mitzvah requires us to publicize the true religion to the masses. This must be done without fear of retribution, to the extent that even if a powerful tyrant tries to force us to deny G‑d (exalted be He), we may not obey him. We must rather unquestioningly submit to death, not even allowing him to think that we have denied G‑d (exalted be He) [by outwardly denying Him], even if we still maintain belief in Him in our hearts. (emphasis mine)

The Gemara (Temurah 3b) also explains:

The Gemara resumes the discussion of one who curses another: Rather, the term vehifla in Deuteronomy 28:59 comes to teach what? It comes to teach that one who curses another using the name of G-d is flogged. The Gemara asks: But why not say that that verse refers to one who pronounces the name of Heaven in vain? The Gemara answers: Even if it does, is cursing another using the name of G-d any less of a sin than pronouncing the name of Heaven in vain? If one is flogged for the latter, certainly one is flogged for the former.

Also, the Shulchan Arukh (Choshen Mishpat 27:1) states (footnote 3):

One who curses an Israelite,1 and even [if] he curses himself,2 — by the [Divine] Name or by a substitute,3Mishna ibid.: ‘(If one said to witnesses, I adjure you) by Alef-Daleth (the first two letters of Adonai, the Lord) or by Yod-He (the Tetragrammaton) or by Shaddai (the Almighty) or by Ẓebaoth ([Lord] of Hosts) or by the Merciful and Gracious One, or by Him that is long-suffering and of great kindness, or by any of the substitutes of the Name, they are liable … If a man cursed himself or his fellow by any of them, he transgresses a negative precept.’ Gemara ibid. 36a: ‘R. Jannai said: This is the view of both (i.e., R. Meir and the Sages both agree that one who curses himself or his neighbour not merely by the Name, but even by any of the substitutes, transgresses a negative precept).’ or by one of the names that the heathens call the Holy One, Blessed be He,4 — if this took place in the presence of witnesses5 and [was preceded by] warning,6 he receives lashes7 on account of [the negative precept] 'Thou shalt not curse the deaf,'8 and if [the cursed person] was a Judge, he receives additional lashes on account of [the negative precept] 'Thou shalt not curse the Judges.'9 And [if one cursed by] Arur it is considered a form of curse.10