As of Aug 4, 2016: Though all models for black hole binaries may be created equal (except those inferior ones proposed by our competitors), we hope that observational data will soon make them decidedly unequal. We hold these truths to be self-evident, at least after much hard thought and fine tuning, with the indicated caveats:

  1. If LIGO finds M_1>30Msun binary black holes with a mass ratio 0.2<q<0.5, then they are not a result of chemically homogeneous evolution of isolated binaries (i.e. in vacuum, no star cluster exchanges, triples or AGN disks).
  2. If LIGO finds an 80-130Msun BH in a black hole binary (isolated: not in a star cluster, triple, or AGN disk), it will conclusively rule out the theory of pair instability supernovae, which is straightforward and has no major adjustable parameters. Audience agrees that the only allowed loophole could be results of multi-d simulations of extremely rapidly rotating stellar cores.
    • If the spins of the black holes are both aligned with the orbital angular momentum, we all agree not to publish any papers proposing that the system was formed by dynamical interactions in a star cluster.
  3. If LIGO finds that the rate R of merger of M1+M2>100 Msun black hole binaries is greater than 1/4 the rate of merger of M1+M2>20 Msun black hole binaries, then the former cannot be a result of "conventional" (inhomogeneous, common-envelope) evolution, unless top-heavy IMFs or peculiar natal kick velocities scaling inversely with mass are invoked.
  4. If LIGO correlations with galaxy positions indicate that the typical BBH mergers are correlated with L* spiral galaxies, then the BBH mergers are not a result of Z<1/10 solar chemically homogeneous evolution, if it is confirmed that most low Z stars are currently in low Z environments. [NOT GENERALLY APPROVED]
  5. If one or both black hole spins are always aligned with the orbital angular momentum, then dynamically (cluster exchange) formed binaries do not contribute significantly to the rate of BBH merger.
  6. If in an approximately equal-mass BBH, both spins are large (a/M>0.5) and aligned with the orbital angular momentum, chemically homogenous evolution will be accepted as the origin. [NOT APPROVED]
  7. If in an approximately equal-mass BBH, one spin is large (a/M >0.5) and aligned with the orbital angular momentum, but the other small (a/M<0.1), a wide orbit shrunk by common envelope evolution will be accepted as the origin.
  8. If most spins in BBH mergers are found to be small (<0.2), and Wolf-Rayet mass loss is determined to be <10^{-6}Msun/y, with no late stage LBV mass loss, Z<1/10 solar chemically homogeneous evolution will be abandoned as an explanation for their origin. [Cantiello will allow >100G ordered magnetic field in very massive WR stars: he will supply upper stellar mass limit for this statement to be accepted.]
  9. If radial velocity measurements by integral-field spectrgraphs fail to find any binaries consisting of a massive black hole and a ~0.8Msun main sequence star in globular clusters of low enough density that most of their black hole binaries should not have been ejected, then globular clusters will be abandoned as a significant source of BBH mergers. [Models to be looked at by Rodriguez to define numbers].
  10. If no luminous red supergiants of >45Msun are found in galaxies of SMC or lower metal abundance, the standard (inhomogeneous, common-envelope) model for formation of 30+30Msun BBH will be abandoned. [Radius vs Red vs Yellow vs Blue, and numbers to be investigated]
  11. If LIGO observes a BBH that has an eccentricity greater than e ~ 10^{-2} when it enters the LIGO band, then dynamical formation will be accepted as the origin.

[Proposed Aug 2, 2016 and transcribed by Sterl Phinney; caveats and tunings added by program members]
Declaration ratified on Aug 12, 2016 by:
Duncan Brown
Tomasz Bulik
Alessandra Buonanno
Matteo Cantiello
Selma de Mink
Ben Farr
Chris Fryer
Gregg Hallinan
Daniel Holz
Juna Kollmeier
Shri Kulkarni
Astrid Lamberts
Luis Lehner
Yuri Levin
Andrew MacFadyen
Pablo Marchant
Lidia Oskinova
Sterl Phinney
Eliot Quataert
Enrico Ramirez-Ruiz
Carl Rodriguez
Naoki Seto
Tyrone Woods
Stan Woosley


Astrid Lamberts has shared the data for her star formation rates. The files are available at her website. A description:
The following has the data from Fig.1 in Lamberts, Garrison-Kimmel, Clausen and Hopkins 2016. It provides star formation rates (in Msun/year/Mpx^3) in 100 million year time bins, over 11 metallicity bins.