Resolution criteria

This market will resolve to YES if, on or before December 31, 2030, a peer-reviewed scientific paper is published by a recognized cosmological collaboration (e.g., Simons Observatory, BICEP/Keck, SPT, ACT, LiteBIRD, or a successor CMB experiment) announcing the first detection of a primordial tensor-to-scalar ratio $r$ that meets the following criteria:

1. The reported best-fit value of $r$ is strictly greater than 0.003 ($r > 0.003$).

2. The detection rules out the null hypothesis ($r = 0$) with a statistical significance of at least $3\sigma$ (three standard deviations, or a 99.7% confidence level).

3. The detection is based on primordial B-mode polarization measurements of the Cosmic Microwave Background (CMB).

If no such peer-reviewed publication is released by the cutoff date, if the best-fit value of $r$ is $\le 0.003$, or if the significance of the detection is less than $3\sigma$, this market will resolve to NO.

Note on edge cases:

• Preprint publications (e.g., on arXiv) do not qualify; the paper must be published in a peer-reviewed journal by December 31, 2030.

• If a paper meeting the criteria is published but subsequently retracted prior to the market's resolution, the retracted paper will not count toward a YES resolution.

• Subsequent scientific debates or conflicting papers published after a qualifying peer-reviewed discovery paper will not affect the resolution, provided the initial paper met all criteria at its time of publication.

Background

The tensor-to-scalar ratio ($r$) quantifies the amplitude of primordial gravitational waves (tensor perturbations) relative to density perturbations (scalar perturbations) in the early universe. A definitive detection of $r > 0$ would provide historic, direct evidence for the theory of cosmic inflation, which posits that the universe underwent a phase of exponential expansion in its earliest fractions of a second. Many of the most popular and simple models of inflation—such as Starobinsky inflation or Higgs inflation—predict a minimal value of $r \approx 0.003$ to $0.004$.

As of 2026, the most stringent constraints limit the tensor-to-scalar ratio to $r < 0.032$ (at 95% confidence). Several next-generation Cosmic Microwave Background (CMB) experiments are actively operating or in development to hunt for this signal. This includes the ground-based Simons Observatory in Chile, which is targeting a sensitivity of $\sigma(r) \approx 0.003$, and the space-based LiteBIRD satellite mission planned by JAXA, which targets a total uncertainty of $\sigma(r) < 0.001$.

This description was generated by AI.