The Probability of Vacuum Metastability and Artificial Vacuum Decay: Expert Survey Results

TL;DR

The paper surveys a curated set of quantum-field-theory and cosmology experts to quantify two probabilities: $P(\text{vacuum metastable})$ and $P(\text{inducible})$ for vacuum decay. Using an anonymous survey of $n=20$ responses from $17$ institutions, it reports a mean $P(\text{metastable})$ of $45.6\%$ (SD $33.7\%$) and a mean $P(\text{inducible})$ of $18.8\%$ (SD $42\%$), with opinions split across agnostic, high-probability, and low-probability groups. The results indicate substantial disagreement tied to uncertainties in physics beyond the Standard Model, especially at high energy scales, and most respondents view artificial induction as technologically challenging, even for advanced civilizations. The study is exploratory, highlighting that resolving these questions hinges on theoretical advances beyond the SM and precise Higgs-sector measurements, and it underscores the need for further interdisciplinary discussion on existential risk from vacuum decay.

Abstract

Vacuum decay posits that the universe's apparent vacuum is metastable and could transition to a lower-energy state. According to current physics models, if such a transition occurred in any location, a region of "true vacuum" would propagate outward at near light speed, destroying the accessible universe as we know it by deeply altering the effective physical laws. Understanding whether advanced technology could potentially trigger such a transition has implications for existential risk assessment and the long-term trajectory of technological civilizations. We present results from what we believe to be the first structured survey of physics experts (n = 20) regarding both the theoretical possibility of vacuum decay and its potential technological inducibility. The average responded probability that our vacuum is metastable was 45.6%, with an average estimated 18.8% probability that arbitrarily advanced technology could induce vacuum decay if our vacuum is metastable. However, the survey revealed substantial disagreement among respondents on both whether the vacuum is metastable, and, if it is, whether vacuum decay could be artificially induced with arbitrarily advanced technology. According to participants, resolving these questions primarily depends on developing theories that go beyond the Standard Model of particle physics. Among respondents who considered vacuum decay theoretically possible, it was generally expected that artificial induction would pose significant technological challenges even for a civilization with galactic resources.

Figures (7)

• Figure 1: Positions of respondents to the survey.
• Figure 2: Respondents recorded what their opinions in the survey were based on. (A) Confidence that their estimates reflect the key scientific and philosophical considerations available at the present time. 1 = Low confidence, 5 = High confidence. (B) Response on whether their opinion on the possibility of vacuum decay is mostly informed by opinions of colleagues or personal assessment. 1 = opinions of colleagues, 5 = personal assessment.
• Figure 3: Responses to the question: "How likely (0%-100%) do you think it is that the apparent vacuum of the quantum field theory describing our observable universe today is in fact only metastable, so that vacuum decay is physically possible?” The mean response was 45.6%. n = 20, standard deviation = 33.7%.
• Figure 4: Reasoning pathways that explain most (14/20) of the responses to the question of whether our universe’s vacuum is metastable. One person responded 10% as a geometric mean, so has been grouped with the "50%” responses.
• Figure 5: Respondents were asked "Conditional on the apparent vacuum being only metastable, how likely (0%-100%) do you think it is that a transition to a lower-energy vacuum could reliably be induced (purposefully or accidentally) with arbitrarily advanced technology?”. The mean response was 18.8%, n = 20, standard deviation = 42