Intro
Ahmadis are brainwashed to believe a slew of arguments.  All of these arguments collapse upon cross examination.  Another argument that Ahmadis make is that the Quran never says that Esa (As) is alive.  They will throw out challenges and etc in this regard.  However, the issue is that Ahmadis forget that everyone in heaven is alive, no one is dead.  In fact, the Quran tells us that all humans never really die permanently, instead, death is just the beginning of eternal life.  Thus, its no wonder why most Muslims consider that Esa (As) is alive in heaven, since 4:159 tells us that Esa (As) hasnt died yet.  Further, as Esa (As) awaits his return, he must be alive, since heaven doesn’t consist of the dead.

Some quranic evidence
(153. O you who believe! Seek help in patience and As-Salah (the prayer). Truly, Allah is with As-Sabirin (the patient).) (154. And say not of those who are killed in the way of Allah, “They are dead.” Nay, they are living, but you perceive (it) not.)

And do not think of those killed in Allah’s path as dead: indeed they are alive and receive their sustenance from their Lord. They rejoice in the bounty provided by Allah. (Surah 3, Aal-e Imran verse 169-170)

Some hadith evidence

Masruq reported: We asked Abdullah ibn Mas’ud about the verse, “Do not think those who are killed in the way of Allah are dead. Rather, they are alive with their provision in the presence of their Lord.” (3:169) Abdullah said: We asked the Prophet, peace and blessings be upon him, about this verse and he said, “The souls of martyrs are alive in the bodies of green birds who have their nests in chandeliers hanging from the Throne of the Almighty. They eat the fruits of Paradise from wherever they wish and they nestle among these chandeliers. Once their Lord cast a glance at them and he said: Do you want anything? They said: What more could we desire? We eat the fruit of Paradise from wherever we wish. Their Lord asked them the same question three times. When they saw that they will continue to be asked, they said: O Lord, we wish that you could return our souls to our bodies so that we could be martyred in your way once again. When Allah saw that they had no needs, he left them to enjoy.”

Source: Sahih Muslim 1887