English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The LIGO/Virgo gravitational--wave observatories have detected 50 BH-BHcoalescences. This sample is large enough to have allowed several recentstudies to draw conclusions about the branching ratios between isolatedbinaries versus dense stellar clusters as the origin of double BHs. It has alsoled to the exciting suggestion that the population is highly likely to containprimordial black holes. Here we demonstrate that such conclusions cannot yet berobust, because of the large current uncertainties in several key aspects ofbinary stellar evolution. These include the development and survival of acommon envelope, the mass and angular momentum loss during binary interactions,mixing in stellar interiors, pair-instability mass loss and supernovaoutbursts. Using standard tools such as the population synthesis codesStarTrack and COMPAS and the detailed stellar evolution code MESA, we examineas a case study the possible future evolution of Melnick 34, the most massiveknown binary star system. We show that, despite its well-known orbitalarchitecture, various assumptions regarding stellar and binary physics predicta wide variety of outcomes: from a close BH-BH binary (which would lead to apotentially detectable coalescence), through a wide BH-BH binary (which mightbe seen in microlensing observations), or a Thorne-Zytkow object, to a completedisruption of both objects by pair-instability supernovae. Thus since thefuture of massive binaries is inherently uncertain, sound predictions about theproperties of BH-BH systems are highly challenging at this time. Consequently,drawing conclusions about the formation channels for the LIGO/Virgo BH-BHmerger population is premature.

The Uncertain Future of Massive Binaries Obscures the Origin of LIGO/Virgo Sources