As you know, many Avengers 4 theories are around, but only one of them is really important. "Quantum theory" for the new Avengers movie is one of the most important theories that will take place in Avengers 4. The director of Ant-Man and the Wasp, Peyton Reed, made an important statement in recent months and told that Quantum will play an important role in this film.
We didn't hear anything new about quantum theory for a long time. Until the last day. A new statement on this theory came from Michael Douglas. Douglas talked about the importance of the Quantum Universe in Avengers 4 at "On Air with Ryan Seacrest".
The Avengers 4 will be built on the Quantum Universe
"I mean, all of them. The Quantum Realm, that’s the key. That’s the key. The Quantum Realm plays an important part in all the next chapters, I think, of the Marvel films."
Apparently, the quantum theory seems to be being talked for longer than we expected. Because of the famous actor's speech, details about the quantum theory can continue to be revealed. Also, we know that Michael Douglas will be featured in Avengers 4, as one of the most important details of Avengers 4 will be quantum theory. In addition, recently, one of the dresses which our heroes will wear was leaked on internet, and one of the armours was named Quantum Armour.