what happen if numenor didnt rebel against the valar?

[Alfirin]

Originally Posted by Zigûr

We don't know for sure that Gil-galad would survive a war. Also, why "no Iron Hills or Erebor"? This wouldn't stop the Dwarves uncovering the Balrog in the Third Age as they continued to mine for mithril.
Also I think no matter their amount of their success the Noldor would have waned in the Third Age because it was not in their nature to stay in Middle-earth. They would have faded in any event.

I agree about the Iron Hills, but Erebor might indeed have not existed. No Sauron means no Dol Guldur (or, at least, no necromancer in Dol Guldur). At minimum, This probably means a very different second half of the Quest; one with Gandalf there the whole time, which might have changed events dramatically Less trouble (if any) with the spiders, the elves (They would be dealing with a party in much better shape (less starving and full of spider venom), if indeed Gandalf didn't figure out a way to skirt around the elves entirely (or, otherwise, enter the elven kingdom in a manner much more amenable to the parties interest (assuming Ganadalf is liked by the Elves of Mirkwood as much as he is by those of Rivendell).
But most likely, the Quest would have been completely different. No Nercomancer would be that Thrain would most likey never have been captured and imprisioned and even more likely that Gandalf would never have found him With no necromancer, why would he ever go to Dol Guldur? (Evne if we are talking about a scenario where Sauron is still alive; held captive on Aman and the Ring still exists (so theoretically, so do the Ringwraiths, all that would be at Dol Guldur would be at best, a Nazgul forever divorced from his master; probably not big enough for Ganadalf to decide to go.) Thrain would most likely have passed the map onto Thorin directly (along with the Dwarven ring, which in this scenario he probably still has) or equally likely, have tried to take back Erebor himself; far earlier in time than Thorin did. In either case, it would probably be a quest sans Gandalf (with Thrain never captured, Gandalf would have never met him, and with no map to give Thorin he never would have met him either.) and definitely without Bilbo. So you'd probably be looking at a quest that ultimately failed (Thrain would probably have had him and his party try and rush the dragon dwarf style, and gotten the whole company roasted for his trouble.) And if by some miracle Smaug's death ocurred more or less as it did in the real quest, the later events would have turned out a lot worse. With no Bilbo to try and soothe the situation with the Arkenstone the Dwarves,Men, Elves and Goblins, assuming the latter two even showed up (if thrain took a path that did not end up with them contacting the Golblins or Mirkwood elves and alterting them that there were Dwarves trying to take back Erebor, one or both might not have showed up. With no Gandalf, the Eagle DEFINITELY would not have). Would likely have slaugtered each other. A lack of Sauron would probably not have stopped Erebor from being FOUNDED, but the events resulting from his non-presence in the Third age would probably have resulted in there being no Dwarven kingdom of Erebor later (though in a world without the war of the ring, that might not have mattered much)

[tom the eldest]

Do sauron use mumakil in battle,is so,then sauron have a slight advantage against the numenorean.and it doesnt matter if sauron dont go back to mordor.he would fled to the east,far away from the numenorean.then,before either men or elves or dwarves know it,boom!sauron come from the east with huge number of men,trolls,and horses,then from the south the haradrim and mumakil come.in the east,sauron would be able to experiment much easily and without numenorean or noldor watch.he could make black uruk,uruk hai,and olog hai.

[tom the eldest]

About the balrog,the dwarves would still find the balrog,but with the numenorean around,the dwarves would most likely seek help to the numenorean.if the numenor army could make saurons army routed without fighting,could they send there entire army to moria and ousted the balrog from moria?

[Zigûr]

Originally Posted by tom the eldest

before either men or elves or dwarves know it,boom!sauron come from the east with huge number of men,trolls,and horses,then from the south the haradrim and mumakil come.in the east,sauron would be able to experiment much easily and without numenorean or noldor watch.he could make black uruk,uruk hai,and olog hai.

"But Sauron struck too soon, before his own power was rebuilt" (Appendix A)
The idea that Sauron could somehow flee to Middle-earth (again, why would the Númenóreans exile him back to his own lands?) and immediately, spontaneously restart his military operations is not supported in the text. In fact, the opposite was true - his armies weakened in his absence.
Given that the Uruk-hai and the Olog-hai were not bred until the Third Age, we can hardly know for sure that Sauron would inevitably develop them in the Second under different circumstances. What do you mean by "black uruks"? As far as I'm aware that's just another name for "Uruk-hai."
You also seem to think that the Mumakil are some kind of superweapon, but beyond their use at the Pelennor Fields where the Haradrim and their oliphaunts were still defeated and destroyed I see no evidence of that.

Originally Posted by tom the eldest

if the numenor army could make saurons army routed without fighting,could they send there entire army to moria and ousted the balrog from moria?

The Balrog wasn't discovered until the Third Age. The events we're talking about here would have happened in the Second Age.

Originally Posted by Alfirin

A lack of Sauron would probably not have stopped Erebor from being FOUNDED, but the events resulting from his non-presence in the Third age would probably have resulted in there being no Dwarven kingdom of Erebor later (though in a world without the war of the ring, that might not have mattered much)

A lack of Sauron in the Third Age would change events in the Third Age so drastically that we can't be sure any of them would still be recognisable. For all we know, Smaug might never have come to Erebor even if it was founded - it only became rich after the abandonment of the Grey Mountains after all, and the Cold-drakes might never have come to the Grey Mountains in a world devoid of Sauron for any number of reasons. Similarly, why would the Wizards be in Middle-earth in the Third Age if Sauron was not there? Resisting him was the entire reason they were sent.

[William Cloud Hicklin]

The Mumakil seem to have been about as useful as real-world war elephants: not very. Their advantage was that they frightened horses and so neutralised cavalry, but they proved almost impossible to persuade or goad to trample and crush formed infantry, and eventually were relegated to mobile but vulnerable archery platforms- but ones with an unpleasant tendency to go berserk and then indeed crush and trample everyone, friend and foe alike.

Hannibal brought elephants over the Alps- but they didn't do him a darn bit of good. They were useless (and most died) at Trebia, and Lake Trasimene and Cannae were won by conventional soldiery and canny generalship.

[Inziladun]

Originally Posted by William Cloud Hicklin

The Mumakil seem to have been about as useful as real-world war elephants: not very. Their advantage was that they frightened horses and so neutralised cavalry, but they proved almost impossible to persuade or goad to trample and crush formed infantry, and eventually were relegated to mobile but vulnerable archery platforms- but ones with an unpleasant tendency to go berserk and then indeed crush and trample everyone, friend and foe alike.

The wolf-riders used by Saruman seem to have fulfilled the same function with more efficiency and greater numbers. Showy and awe-inspiring though they were, the mûmakil were indeed noticeably ineffective in the glimpses given the reader. Maybe they were better suited for the lands of their origin.

[Alfirin]

Originally Posted by Zigûr

"But Sauron struck too soon, before his own power was rebuilt" (Appendix A)
A lack of Sauron in the Third Age would change events in the Third Age so drastically that we can't be sure any of them would still be recognisable. For all we know, Smaug might never have come to Erebor even if it was founded - it only became rich after the abandonment of the Grey Mountains after all, and the Cold-drakes might never have come to the Grey Mountains in a world devoid of Sauron for any number of reasons. Similarly, why would the Wizards be in Middle-earth in the Third Age if Sauron was not there? Resisting him was the entire reason they were sent.

I concede both points. There might still be some remmnant of Sauron's shadow in ME, in the form of the Wraiths, assuming a scenario where the Valar are holding Sauron Captive on Aman, but do not consider it neccecary to deprive him of the ring, as, like Sauron Himself, keeping it on Aman deprives it of much of it's power (not in the sense either is weakend, but in the sense that, being basically in a place it can't get back from, and can't really influence [I'm imagining that Aman, being the domain of the Valar themselves, is the one place where Suron's ability to corrupt would get basically nowhere; that Sauron does not and never had, sufficient power to turn the elves of the Undying Lands agaist the Valar, especially not on thier own territory.) In fact, theoretically, ME under these circumstances might theoretically be facing thirteen wraiths, not nine (If I recall, Sauron had given away six of the mortal rings by the time he submitted at Umbar. Assuming that those still did what they did, that's six Nazgul. If you point was right and an absence of Sauron might have resulted in an elmination of the cold drakes from the Grey mountains, it is possible none of the Dwarven rings would ever have been destroyed (or does it take a fire drake to destroy a ring? I've forgotten which rings were destroyed by which dragons.) Assuming that Dwarven rings eventually corrupt too (we are told Dwarves are more resistant than men, but resistant isn't the same thing as immune.) Eventually they might be wraithified as well making thirteen.) But I agree, those kinds of threats might not be enough to cause the Valar to send the Ishatari, or at least, not all of them (Manwe/Nienna might still want to send one (i.e. Gandalf) since they seem to be a little more concerned with the People of ME than most of the Valar (and so might consider the threat to still be great enough to send some help) But the rest would probably be harder to convince and even if Gandalf WAS eventually sent, he'd likey be going it alone.)
The Balrog is likewise a similar thorny matter. It presumably WOULD still be unleashed; it's release was completely unrelated to anything Sauron did (though, in a world where theoretically there were more Dwarven rings available, it is possible that either Durin VI or one of his predecessors would have had one and it's aura of greed might have led to deep mining and Durin's Bane being released somewhat earlier) But even that might have required no higher intervention. A less damaged Eregion might have joined with the Dwarves and together been able to deal with it. Alterntively, a world where there was no Gandalf might mean a Moria that could NEVER be reclaimed, since there might be no power in ME capable of doing so.
But you are right, everything is theoretical in those circumstances.