What does it actually mean to say something is “likely” in science?

The Random Universe: How Models and Probability Help Us Make Sense of the Cosmos explores how scientists use probability to draw conclusions about the universe from limited, uncertain data—and what we really mean when we call a theory “likely.”

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If you read it, a short review on Goodreads or Amazon really helps others find it.

The Random Universe tells the story of how scientists use data to interpret and model the universe, combining philosophy and the history of science—from David Hume’s question “can we know anything more than what we experience?” to the work of Thomas Bayes and modern cosmology.

With examples such as Eddington’s 1919 eclipse expedition confirming Einstein’s theory of gravity, it shows how models and probability are used to predict and explain—and why scientific conclusions are always, in some sense, uncertain. My aim is to show how scientists build and test models of the world, and why that process matters for how we decide what is true.

Prefer a quick introduction? Watch a short talk about the book here, or find recent and upcoming appearances.

Unfortunately, some randomness has crept into the book: errata (inevitably!) can be found here.