The word "yawm" in the Quran can mean both a literal day and an indefinite period of time. Science proves that the world cannot be created in 6 twenty-four hour periods but it doesn't deny the world being created in 6 epochs (periods of time). The Bible also says that the world is created in 6 days, but the days in the Bible are literal. And that is a scientific mistake. In fact, Islamic scholars had also suggested the idea that the 6 days don't have to be literal! This is unlike the Christian scholars who denied that.
Shaykh Al-Qaradhaawi said in Hady Al-Islam: “Perhaps these days are six phases and periods and it is only Allaah who knows their duration; each day is defined by the work achieved in it; or it means six astronomical cycles which we do not know, which are other than our days that are related to the solar cycle; or it means six phases that had passed on these creatures. All of this is possible, and the Arabic language may refer this, and the religion does not prevent it.” [End of quote]
Sayyid Qutb may Allaah have mercy upon him says in his interpretation of Surah Al-Furqan [Quran 25]: “The days of Allaah during which He created the heavens and the earth are definitely not our days on earth. Our days are a shadow of the solar system, and a measure of an astronomical cycle which existed after the creation of the heavens and the earth, which is measured by the duration of the rotation of the earth around itself in front of the sun. . . Perhaps these six days are of the days of Allaah which no one knows their extent but Him, but they witnessed the completion of spaced out phases in the heavens and the earth until they ended up in their current state.” [End of quote]