Recent content by tovisonnenberg

Ah, so a combination of greater compaction and a little melting decreases the coefficient of friction?

Hi! I have a question about inclined planes. In the diagram I attached, you can see that, with or without friction, mass does not affect the acceleration of the block. However, in my experience, the more people I put on my sled, the faster it goes. Why is this?

Hey guys! I read this fascinating paper about the discovery of a white dwarf merger remnant: https://www.nature.com/articles/s41586-019-1216-1 To quote the abstract: "For white dwarfs, the mass of the merger product may exceed the Chandrasekhar limit, leading either to a thermonuclear explosion...

Hi! I have a question about integrating Planck's function of blackbody radiation. Why is it that the area under the blackbody curve will be less than the spectral radiance of individual wavelengths? For example, integrating the Sun's curve over all wavelengths yields a smaller value than the...

Hi! I've been browsing the internet for information about supernovae and I came across this chart describing 4 types of core collapse causes (the chart may have copied weirdly because not all the information fits into this text box): Cause of collapse Progenitor star approximate initial mass...

Hello! I was reading up on methods for determining the density of the universe and I came across this page: https://hypertextbook.com/facts/2000/ChristinaCheng.shtml I tried using equation stated, Ω=(2/3Λ)(c^2/H^2), with SI unit versions of both variables: Λ=1.1056 * 10^-52 m^-2 H=2.1927 *...

Hi everyone! I need to use sigma notation to build a summation that "feeds back into itself". By that I mean that it should model a sum whose terms are f(x) + f(f(x)) + f(f(f(x))) and so on. How would I do this?

Hi everyone! Does using the distance modulus—m-M=5log(r/10)—on type 1a supernovae only provide the distance to the host galaxy at the time of the supernova? If so, how would I mathematically determine the present day distance to a galaxy by taking into account both the expansion of the universe...

Hello everyone! I was listening to a podcast that featured a cosmologist and she mentioned that if the universe was positively curved (and therefore a sphere overall), light would travel around the universe and then end up where it started. I wondered, would a gravitational wave do the same?

Hello! I'm attempting to find the mass of a red giant and an AGB star. I have their luminosities, radii, and the masses of their cores. I'm looking for some kind of mass-luminosity relationship. Do you know of any, or do you know of a good place to look for such equations? Thanks!

I added 2 links in the original post. Thanks for letting me know!

I read about a theory (https://en.wikipedia.org/wiki/Magnetospheric_eternally_collapsing_object) (https://arxiv.org/pdf/astro-ph/0602453.pdf) that proposes that collapsing massive stars never actually form a singularity, and instead they end up as "magnetospheric eternally collapsing objects"...

Sorry for the ambiguity. I asked the question because in an article I read by Phil Plait, he said that if you add mass to a brown dwarf it gets smaller due to "degeneracy". I was just seeking clarification on that. Here is the link...

Why wouldn't a brown dwarf grow in radius if it started to gain mass?

When neutron stars collide, heavy elements, such as gold, are created. Are these elements ejected from the system to be found, say, here on earth? Or do they fall back into the newly created black hole?