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The outer boundary is the point where a photon has a ~50% chance of escaping without encountering another particle.

Do you have a source? I'd love to read more. :)

Amateur stargazer's understanding:

Depending what kind of reading material you're looking for (e.g. high level details or mathematically/jargon dense papers) look for things discussing "Rosseland optical depth" and "grey atmosphere approximation".

At a high level, the common convention is to define the radius by finding where the optical depth is 2/3 when using Rosselands clever way of calculating a weighted mean of the opacity from that layer in the star to space across different wavelengths of light. 2/3 being a clever derivation from Eddington where, in an idealized model of a star, that's when the actual temperature of the star should equal its blackbody equivalent temperature.

Pedantically, this distance to the point of equality is an ever so slightly different value than the "distance from the center where there is a 50% chance a photon traveling directly outward will escape the star without another interaction" rule of thumb (in the same idealized grey model). Practically, that the difference is so small is why it's a fantastic rule of thumb explanation.


I'd recommend Carroll & Ostlie's Introduction to Modern Astrophysics, though it requires some basic calculus and physics.

Thanks!

We have constraints that primordial black holes must be less than the size of a large asteroid. They would be gravitationally insignificant to the Earth unless they actually passed through it.

I also don't think it would really be detectable in the Sun. Perhaps there would be some transient astroseismology signature.


They did some modeling in a previous paper of how this would impact Ia supernovae and it depends on whether the supernova is driven by Kelvin-Helmholtz instabilities or not. In the case that it is, this would only trigger Ia supernovae for white dwarfs which are already very close to the Chandrasekhar mass. In this case the standard candles would be pretty much the same.

In the case that KH instabilities are weaker they claim that you can get supernovae at masses farther from the Chandrasekhar limit. This could plausibly have more of an impact on Ias as standard candles. (Though perhaps less than you might think becauseit would also likely have an effect on the shape of the light curve, and Ias are normalized based on their light curve shape.)

All that said, even if this process does occur, I doubt the rates would be high enough for it to be a substantial fraction of observed Ias.


To paraphrase the old joke, if you wake up with a $78,000 AWS bill, you have a problem. If you wake up with a $78 million AWS bill, Amazon has a problem.


We already know that some particles interact extremely weakly with others. Neutrinos were postulated as a "dark" particle in order to preserve conservation of energy and momentum, but it took more than a decade before they were observed directly. There's no reason there couldn't be another particle with an even weaker interaction.


This is the field of information geometry: https://en.wikipedia.org/wiki/Information_geometry


In a similar vein I highly recommend Behind the Curve, which is a documentary about the flat Earth movement. It was a pretty fair film and tried to get to know the people involved in the movement and what it was that motivated them.

It was interesting to see that one of the main figures featured in the documentary started out pretty generically wanting to get into conspiracy theories and started reading up on one after another until he found a particular one that clicked.

https://en.wikipedia.org/wiki/Behind_the_Curve


Did Moltbook even have any investors?


    Moltbook Valuation & Funding
    Deal Type              Date         Amount Raised to Date Post-Val  Status     Stage
    2. Merger/Acquisition  10-Mar-2026  -       -               -         Announced  Startup
    1. Early Stage VC      01-Mar-2026  -       -               -         Completed  Startup


I think the long term impact of this will be to strengthen the importance of social ties in academic publishing. As it is there are so many papers published in many fields that people tend to filter for papers published by big names and major institutions. But the inevitable torrent of AI slop will overwhelm anyone who is looking for any gems coming from outsiders. I suspect the net effect will be to make it even more important that you join a big name institution in order to be taken seriously.


I remember one of my friends in college pointing out before lecture that the professor would always start by saying "OK, So."


I have had to train myself out of doing that when recording videos. The best I've managed is that I can do it sometimes, and most of the rest of the time I leave a long enough pause after that I can cleanly edit it off.


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