If you, and you alone, somehow knew that the result was correct and within a year the world would recognize this what if any stocks would you buy based on your private information?
Unfortunately, this research is so preliminary that there’s no obvious applications that are remotely plausible even under this assumption. Detecting neutrinos is really tough. This means that one a) is going to have a lot of trouble using this to send information faster than the speed of light with any substantial bandwith (and even then you would be getting only a small fractional improvement) b) in order to violate causality to solve computational problems you generally need to be able to send back in time a number of bits that is roughly linear with the length of your problem. It is remotely plausible that similar tricks can be done with fewer bits but if so, very little has been worked out that does that sort of thing in any useful fashion and the math looks tricky. And even if that does work, the infrastructure may be so large that it might not be worth it compared to just building large computers.
So the stocks that would make the most sense are simply companies that have anything to do with pure neutrino research because that is more likely to get more funding. So I’d look at what companies made the equipment for Gran Sasso, Kamiokande and IceCube and maybe buy stock in them. However, I strongly suspect that any company which is publicly traded and involved in these detectors is probably large enough that building components for neutrino research is very likely only a small segment of what they do. So even this would not be that helpful.
Maybe it would just make more sense to invest in tech stocks in general. While one is not getting much of a speed up on each roundtrip, multiple roundtrips, doing a little calculation on each trip, sounds like a major engineering task and not a fundamental task. And if that works, then we get the usual speedup—NP to P or whatever the precise complexity class conversion is, which sounds very economically valuable and whomever maintained the FTL computer would be able to extract much of the surplus.
Unfortunately, this research is so preliminary that there’s no obvious applications that are remotely plausible even under this assumption. Detecting neutrinos is really tough. This means that one a) is going to have a lot of trouble using this to send information faster than the speed of light with any substantial bandwith (and even then you would be getting only a small fractional improvement) b) in order to violate causality to solve computational problems you generally need to be able to send back in time a number of bits that is roughly linear with the length of your problem. It is remotely plausible that similar tricks can be done with fewer bits but if so, very little has been worked out that does that sort of thing in any useful fashion and the math looks tricky. And even if that does work, the infrastructure may be so large that it might not be worth it compared to just building large computers.
So the stocks that would make the most sense are simply companies that have anything to do with pure neutrino research because that is more likely to get more funding. So I’d look at what companies made the equipment for Gran Sasso, Kamiokande and IceCube and maybe buy stock in them. However, I strongly suspect that any company which is publicly traded and involved in these detectors is probably large enough that building components for neutrino research is very likely only a small segment of what they do. So even this would not be that helpful.
Maybe it would just make more sense to invest in tech stocks in general. While one is not getting much of a speed up on each roundtrip, multiple roundtrips, doing a little calculation on each trip, sounds like a major engineering task and not a fundamental task. And if that works, then we get the usual speedup—NP to P or whatever the precise complexity class conversion is, which sounds very economically valuable and whomever maintained the FTL computer would be able to extract much of the surplus.