Question: What is the Islamic position on the concept of time travel? Alternate/parallel worlds? Multiverse?
Answer: assalamu alaykum
Theologically, all of the things you mention are from the realm of the possible.
In Islam, we affirm a type of ‘alternate world’ when it comes to the realm of the barzakh and the alam al-mithal. There are also reports from some of the Salaf, such as Ibn Abbas, that affirm multiple earths: “in every earth is a prophet like your Prophet, an Adam like your Adam, a Nuh like your Nuh, an Ibrahim like your Ibrahim and an Isa like your Isa.” (Mustadrak al-Hakim) Scholars have long debated the soundness and meaning of such hadith.
There are many realities and possibilities in the created realm that Islam has not explicitly spoken about. This is not a negation that they exist or may exist. Ascertaining these realities returns to science, human discovery, etc. As for religion, while it does speak about many realities, its concern is centered on recognizing God and next-worldly salvation.
[Ustadh] Salman
Ustadh Salman Younas was born and raised in New York and graduated from Stony Brook University with a degree in Political Science and Religious Studies. After studying the Islamic sciences online and with local scholars in New York, Ustadh Salman moved to Amman. He studies Islamic law, legal methodology, belief, hadith methodology, logic, Arabic, and tafsir. Ustadh Salman’s personal interests include research into law/legal methodology, hadith, theology, and political theory, government, media, and ethics. He is also an avid traveler and book collector. He currently resides in Amman with his wife.