If the world population of Muslims become the more dominant....

I do not think that is nothing to worry about(calendar), you see people will always use or continue to use what they are use to using, at least not in your life time so why worry? I'll give you an example, there are more Chinese than Americans right, but we still continue to speak in English because that is what we are used to. It's a fast growing economy if you would like to compare that to Islam's growth but are we talking in Chinese right now? of course not. Even if Muslims out number us so what? they are people just like us who have families and does exactly the same things we do we do, maybe what people are afraid of is extremism which is so different from the main stream, the same way I am afraid if holier than thou Christians outnumber us or the racist, or the neo Nazis etc.., but all this are just but a small and isolated group, so as long as all men irregardless of creed will love and respect one another , all of us would be pretty safe, I hope and pray!

See Islam may be the fastest growing religion but Atheism is the fastest growing community of any kind.

I don't think of a change in calendar because it's what we are much familiar with and there is no need for a change unless it has some faults.

Your teacher is correct but your assumptions are quite far-fetched. Even though there is proof that there are statistically more growing numbers of Muslims in the world, it does not mean that several systems like the calendar will be replaced immediately or soon after. The current system of calendar (since this was your reference) has been in existence for a long time and the mere growth of population of a religion does not constitute a change or take-over of the system. Besides, even Muslims are familiar with the Gregorian system as they strive to learn cultures beyond their own. Why change something that works for majority of the people regardless of religion?

this is about faith, or? we always use a masehi calender.

It might. But not anytime soon. Just think about 16% of the world do not have a religion. Christianity is 33% and Islam is 21%. So for those of 16% to change to is Islam will be a long time.

The Islamic calendar is not what you should worry about most. Sharia law is, this set of laws says it is alright to beat up women if they do not listen, it's also okay to throw gays of a building or other high point things like that.

Greetings :) I actually don't think it is likely to happen. The fact is that we have been using the "Jesus"/Church calendar for the longest time. That is tradition. It is true that Islam is fast growing, there are reasons behind this : look at their beliefs. Polygamy is not considered taboo in their religion, which means one guy can have 4 wives and loads of kids. Islam will grow but, I don't see that tradition falling unless ALL RICH COUNTRIES were 100% Muslim which is close to impossible. Just the US alone, Islam won't become the state religion because of 9/11. Get China to become Muslim? You will have to convert the Prime Minister which isn't likely to happen because of Confucianism, Buddhism and Hinduism.

I guess that's possible but I really doubt this will happen anytime soon ... the Christian Religion is by far the largest in the world right now , Islamism might be the fastest growing Religion but Christianity is quite a bit in front of it ... But if this will happen one day , and Islamism will have more followers than Christianity it's very possible that the Islamic Calendar will be used by many more people than before although , i repeat , if this will one day happen , it will take a long time ... Regards