The Omphalos hypothesis is one attempt to reconcile the scientific evidence that the Earth is billions of years old with a literal interpretation of the Genesis creation narrative, which implies that the Earth is only a few thousand years old. It is based on the religious belief that the universe was created by a divine being, within the past six to ten thousand years (in keeping with flood geology), and that the presence of objective, verifiable evidence that the universe is older than approximately ten millennia is due to the creator introducing false evidence that makes the universe appear significantly older.

The idea was named after the title of an 1857 book, Omphalos by Philip Henry Gosse, in which Gosse argued that for the world to be "functional", God must have created the Earth with mountains and canyons, trees with growth rings, Adam and Eve with fully grown hair, fingernails, and navels (ὀμφαλός omphalos is Greek for "navel"), and all living creatures with fully formed evolutionary features, etc., and that, therefore, no empirical evidence about the age of the Earth or universe can be taken as reliable.

Various supporters of Young Earth creationism have given different explanations for their belief that the universe is filled with false evidence of the universe's age, including a belief that some things needed to be created at a certain age for the ecosystems to function, or their belief that the creator was deliberately planting deceptive evidence.

The idea was widely rejected in the 19th century, when Gosse published his aforementioned book. It saw some revival in the 20th century by some Young Earth creationists, who extended the argument to include visible light that appears to originate from far-off stars and galaxies (addressing the "starlight problem").

Stories of the beginning of human life based on the creation story in Genesis have been published for centuries. The 4th-century theologian Ephrem the Syrian described a world in which divine creation instantly produced fully grown organisms:

Although the grasses were only a moment old at their creation, they appeared as if they were months old. Likewise, the trees, although only a day old when they sprouted forth, were nevertheless like ... years old as they were fully grown and fruits were already budding on their branches.

By the 19th century, scientific evidence of the Earth's age had been collected, and it disagreed with a literal reading of the biblical accounts. This evidence was rejected by some writers at the time, such as François-René de Chateaubriand. Chateaubriand wrote in his 1802 book, Génie du christianisme (Part I Book IV Chapter V), that "God might have created, and doubtless did create, the world with all the marks of antiquity and completeness which it now exhibits." In modern times, Rabbi Dovid Gottlieb supported a similar position, saying that the objective scientific evidence for an old universe is strong, but wrong, and that the traditional Jewish calendar is correct.

In the middle of the 19th century, the disagreement between scientific evidence about the age of the Earth and the Western religious traditions was a significant debate among intellectuals. Gosse published Omphalos in 1857 to explain his answer to this question. He concluded that the religious tradition was correct. Gosse began with the earlier idea that the Earth contained mature organisms at the instant they were created, and that these organisms had false signs of their development, such as hair on mammals, which grows over time. He extended this idea of creating a single mature organism to creating mature systems, and concluded that fossils were an artifact of the creation process and merely part of what was necessary to make creation work. Therefore, he reasoned, fossils and other signs of the Earth's age could not be used to prove its age.