Cosmology · Contested
'Universe from Nothing' Proposals and the Meaning of Quantum 'Nothing'
Proposals by physicists such as Lawrence Krauss that the universe could have arisen from a quantum vacuum 'without violating the conservation of energy' have been widely criticized by philosophers and some physicists on the grounds that a quantum vacuum, as physics describes it, is a physically structured state governed by pre-existing laws, and is therefore not equivalent to metaphysical nothingness.
The evidence explained
Lawrence Krauss's popular book A Universe from Nothing (2012) argues that quantum field theory shows how particles, and by extension entire universes, could spontaneously arise from a vacuum state through quantum fluctuations, without any additional cause, and frames this as undermining theological arguments that require a cause for the universe's existence. The book's central physical claims draw on established, empirically supported features of quantum field theory, including vacuum fluctuations and particle-antiparticle pair production, which are genuine and well-tested phenomena within existing spacetime.
The most substantial criticism, articulated forcefully in a widely discussed New York Times review by philosopher of physics David Albert, and echoed by other physicists and philosophers, is that the 'nothing' Krauss describes, a quantum vacuum, is not nothing in the philosophically relevant sense of the complete absence of anything, including physical laws, fields, and spacetime, but is rather a specific, richly structured physical state that itself requires the pre-existence of quantum fields and the laws of quantum mechanics governing them. On this view, Krauss's argument, whatever its value as physics, does not actually address the philosophical or theological question of why there is something (including quantum fields and laws) rather than absolutely nothing.
Krauss and some defenders have responded that demanding an explanation for the laws themselves simply pushes the question back a level and that physics may eventually explain even the origin of these laws through deeper, more fundamental physical principles, a response Albert and other critics consider question-begging with respect to the specific philosophical challenge posed, since any 'deeper' physical explanation would itself still be something rather than absolute nothing.
This debate is a useful case study in the necessity of definitional precision in exchanges between physics and philosophy: much of the disagreement stems from an equivocation between 'nothing' as used technically by physicists (an unstable, energetically lowest-possible physical vacuum state) and 'nothing' as used by philosophers addressing the classical question of existence (the complete absence of any entity, law, or property whatsoever). Recognizing this distinction does not settle whether theism or naturalism better explains cosmic origins, but it does clarify that the specific 'universe from nothing' argument, as popularly framed, does not resolve the philosophical question it claims to address.
What it does show
- • Quantum vacuum fluctuations are a real, well-established physical phenomenon within existing quantum field theory and spacetime.
- • Popular claims that physics has explained how 'something came from nothing' typically use 'nothing' in a technical sense that differs from, and does not resolve, the philosophical question of absolute nonbeing.
What it does not show
- • It does not establish that the universe's ultimate origin has been explained without any cause or pre-existing reality, since quantum vacuum states are not metaphysical nothingness.
- • It does not settle the philosophical debate over the Leibnizian question of why there is something rather than nothing at the most fundamental level.
- • It does not, on its own, favor either theism or naturalism, since both sides must still account for the origin of whatever most fundamental laws or entities are posited.
Primary sources and literature
- Lawrence M. Krauss, A Universe from Nothing (2012)Primary popular-science source for the argument being critiqued.
- David Albert, 'On the Origin of Everything' (New York Times Book Review, March 23, 2012)Influential philosophical critique of Krauss's use of 'nothing.'
- Edward Feser, 'Recovering a Theory of Existence' (blog and print essays responding to Krauss)Philosophical (Thomistic) critique of the physics-nothing equivocation.
Where scholars disagree
Physicists and philosophers broadly agree on the underlying quantum field theory phenomena Krauss describes but disagree sharply over whether his argument addresses, rather than equivocates on, the philosophical question of absolute nothingness.
For further study
Primary and secondary sources on both sides of this question. Reading the strongest opposing case is part of the work, not a concession.
The Beginning of the Universe — Alexander Vilenkin (Many Worlds in One)
A cosmologist on why classical spacetime appears to have a beginning, in his own words rather than filtered through apologetics.
The Kalam Cosmological Argument (2 vols.) — Paul Copan and William Lane Craig (eds.)
The scholarly state of the debate on both the philosophical and physical premises.
A Universe from Nothing — Lawrence Krauss
The best-known attempt to make cosmic origins require no cause; note carefully what 'nothing' means in it.
The Big Picture — Sean Carroll
A leading physicist's naturalistic account of reality, including his direct replies to fine-tuning arguments.