Recent content by Thomas Sturm

Regarding the distribution of dark matter in the Universe, there has just been an article in Nature about the most comprehensive WIMP simulation to date: Universal structure of dark matter haloes over a mass range of 20 orders of magnitude. It contains the following, fascinating picture...

Well, thank you all for this discussion, as it helped me getting a bit wiser. This sums it up neatly. I made "half a step" with my "perfect pendulum" thought without going all the way - so even a star going right perpendicular through the halo of our galaxy might pick up a few tons of ordinary...

Ok, let's leave the "thermodynamics" of dark matter aside as that was not the actual point (of my post). And yes, I am fully aware that temperature is a concept which can not be applied to dark matter - as this would imply particles, for starters. Let F(g) ~ (m1*m2)/r^2 be the gravitational...

Wrong. It interacts gravitationally.

Given the fact that our galaxy consists mostly of dark matter (accounting for roughly 70% of its mass) we know astonishingly little about the stuff. Admittedly, if I could give you a lump of dark matter, you would propably be totally underwhelmed by the "experience". First of all, you wouldn't...

You might find The surface tension of binary liquid mixtures an interesting read. However, what you are dealing with is an emulsion, not a mixture. "Pure Oil" is a mixture (of hydrocarbons) already...and the surface tension (of an emulsion with water) will strongly depend on the chemical...

Hi everyone, I am trying to figure out the following question: What is the typical mass of the plasma (in typical working configuration) in current nuclear fusion reactor designs? https://en.wikipedia.org/wiki/ITER: "...plasma volume of 840 cubic meters..." So all I need is the plasma density...

"The Planck time is the time it would take a photon traveling at the speed of light to across a distance equal to the Planck length. " Is the, very sensible, answer to the original question, then. If I had just googled "planck time length" first...this was just such a "1st-post-idiocity" from...

Maybe we could remove the arbitraryness of the original question regarding units by assuming a base measure of length as 1 Lightsecond = 299796 km = 1 Flash [f]. By using this base, the Planck-Length would become 0.53*10^-43 f. So why is it only roughly half the length that light could cover in...