Recent content by ohwilleke

I knew someone who did them from blimps once.

I saw the same paper this morning and was thinking along the same lines that you are.

Easier on the body, but it makes you more fragile, which could be a good local color plot point. You can. But in the sci-fi/fantasy/adventure genre, really all of the way back to Icarus, in Greek mythology, all of the way to Star Wars, much more than a majority of the time, the literary choice...

To be clear, you mean impact with the ground inside the asteroid, not the asteroid impacting something else. And, it seems that this question doesn't want to consider changes to human physiology that arise from living in space for prolonged period of time, but that probably isn't reasonable to...

It is also worth noting that the commonly quoted figure probably doesn't come from a single experiment, and it isn't necessarily the case that every measurement that goes into the final result comes from the same kind of experiment. Instead it is a weighted average of the best available...

Three plus decades later, I still have almost all of them (and even consult them now and then), over the objections of other members of my family. Indeed, I have a fair number of textbooks that I inherited from my father's college days and I use a couple of them (mostly statistics) on a regular...

The reason that I don't feel like that is very promising is that there are many examples of big differences between inclusive and exclusive measurements of quantities in particle physics that eventually get resolved. The prospect for systemic error is great.

Good catch.

Indeed. The idea that the Yukawa couplings of the Standard Model arise from a dynamical process which @arivero's Koide's waterfall imperfectly reflects is IMHO a very fruitful line of inquiry, and if true, would make the idea that some sort of dynamical process is also driving the values of the...

The reason that this particular example is so hard is not because it is, fundamentally, a huge many body problem, but because the underlying deterministic Newtonian physics equations (the Navier-Stokes equations) are inherently "chaotic" in the mathematical sense that large scale behavior is...

One of the rather surprising observational facts about dark matter distributions in galaxies is that they show surprising similarities to each other without much regard to the history of mass assembly in that galaxy, rather than great diversity based upon their varied histories of mass assembly...

After giving it some more thought, the reason that I think that the simulation rather than the astronomy observations are the main problem is that the precision and bias issues in the astronomy observations, while very real, are also well understood. In contrast, the kinds of dark matter...

This is definitely a possibility. When you are comparing simulations to astronomy observations, I focused on the issues with the simulation. But the astronomy observations have their own issues. One of the great things about a simulation is that, subject to its limitation of being coarse...

Astronomy/cosmology simulations do two main things: 1. They rely on a set of assumptions about the physics involved, which are physics informed, but generally never fully reproduce the known laws of physics and the actual distribution of matter in a galaxy. In part, galaxy scale simulations...

Theoretical physicist C.N. Yang died at the age of 103 years on October 18, 2025. He is the Yang in Yang-Mills theory, which he and his collaborators devised in 1953, which is a generic quantum field theory that is used by scientists to study amplitudes (i.e. vector probabilities) that are...