On reading Vilenkin's recent paper, I believe he fails to refute the CNS conjecture. This is for a very simple reason. When Smolin has discussed the conjecture he has made it clear that it concerns(adsbygoogle = window.adsbygoogle || []).push({}); black holes formed by stellar collapse.

Vilenkin confuses the issue by attempting to switch attention to black holes putatively formed by quantum fluctuations. The abundance of such objects is not what the conjecture is about.

The CNS conjecture is that the fundamental dimensionless constants are at a local max for the production of black holes by stellar collapse. One of the motivations is that the constants are seen to provide for heavier elements such as carbon and oxygen which aid contracting clouds of gas to radiate away heat and promote condensation into stars. Another motivation is that the constants allow supernovae to occur, triggering star-formation.

From the start, in the earliest CNS papers back around 1994, the focus has been on optimality for star-formation and (stellar) gravitational collapse-to-hole. The conjecture is not about formation of holes by quantum fluctuation.

So the conjecture still stands, and is not affected by Vilenkin's paper. Either we are at a local max for black holes formed by stellar collapse, or we are not. The challenge, issued around 1994, is to show that we are not at a local max by pointing out a direction in which varying the constants would cause MORE BLACK HOLES TO FORM BY STELLAR COLLAPSE.

Villenkin's paper is quite orthogonal to this. Still, it raises some issues that might be fun to think about, so I will take some posts to do this and hope for some discussion---in case otherse are interested.

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# Vilenkin unconvincing: CNS concerns stellar collapse black holes

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