On 10/16/15, Jason Wright <jtw13@psu.edu> wrote:
I'm aware of trojans, and I have certainly discussed this possibility with colleagues.
I apologize, I thought we had included the Trojans hypothesis in the paper, but you are right, we did not mention it.
If all of the Trojans you mentioned were somehow in a swarm tight enough to produce one of the dips in the curve, they would have low mutual velocity, and tend to self-gravitate into planet.
--well, maybe. You are not dong a calculation here, just intuiting. It may be mathematically possible for said swarm of pebbles never to collide and just stay with the same "low mutual velocities" forever. I don't see how this can be disproven as a matter of mathematics.
It's possible that the 1:1 resonance with the larger body would preclude this, but the swarm would still experience collisions over the life of the star and grind itself up into dust.
--again, calculation seems needed. The trojans in our solar system have neither ground themselves up into dust, nor gravitated into a planet, after 4 gigayears. Nobody understands how they got there, suggesting making confident assertions might be infeasible. If dust were produced, perhaps it would soon be ejected by the solar wind. If collisions occurred they might produce more small bodies, counteracting the "gravitating into a big body" trend. The fact the mutual velocities "low" might mean collisions do not have enough oomph to "grind into dust" and do not occur frequently. Etc. The calculations might not be trivial. There seems to be a pretty large parameter space to search and finding out which parts of it are ruled out by such thoughts as these, and by observations, and whether any part of said space survives, is not something you can do by waving your hands.
So given the age of the star, this is an unlikely solution, but it's a good idea to keep thinking about. Jason
--I'm sympathetic to your objections, and they might be right, but it requires calculation. Also, the papers I saw did not attempt to make numerical estimates of HOW unlikely various candidates were, which if you are comparing unlikely #1 versus unlikely #2, seems essential... For example I saw you quoted saying alien megastructures had to be regarded as the most unlikely candidate, but saw zero calculation of any likeliness number for that or main rival hypotheses. Personally, I thought the alien megastructures looked pretty likely compared to the candidates I saw listed, which is one reason I invented the trojan idea. I mean, you yourself had observation-based objections to every one of your own listed rival ideas, but the alien megastructure idea has zero objections to it (no?) which would seem to make it the MOST not least likely? I mean if we are going to base it on evidence not on prejudices...