Multiverse scientists often point to the string theory landscape to support the idea that the constants of nature may be different in different universes. According to this claim, string theory allows for a huge number of possible universes, each with its own physical laws. In this essay, we explain what the string theory landscape is, how it leads to the multiverse, and whether this conclusion is really justified. To do this, we first give some background on how string theor

A naive multiverse theory tries to explain fine-tuning by saying that if there are infinitely many universes, every possible universe exists somewhere, including one as ordered and fine-tuned as ours. At first, that may sound like a powerful answer to the evidence for design. But infinite universes alone don’t explain fine-tuning. Without the additional premise that our universe is typical, the naive multiverse collapses into what we’ll call a “multiverse of the gaps.” This e

This essay will discuss something that many people fail to mention about the multiverse - that it actually attempts to make a prediction.

One of the strangest predictions to come out of modern multiverse cosmology is the idea that you might not be a normal human observer at all. According to certain multiverse and eternal inflation models, random fluctuations in empty space could occasionally produce a single self-aware brain, complete with vivid memories of a past that never happened. This hypothetical observer is called a Boltzmann Brain. Because forming one isolated brain by chance is vastly easier than form