3 ms·

What Lights the Universe’s Standard Candles?

75 points by Amorymeltzer 4y ago

andrewflnr 4y ago
Whoa. I didn't know the accretion theory of Ia supernovae was dead, much less that it had been since 2011.
andreareina 4y ago
Wouldn't double detonation show up as variance in the brightness?
- yencabulator 4y ago
  Or widening of the peak. If one type Ia supernova goes 1,2,3,2,1, the sum of two could go 1+0=1 2+1=3 3+2=5 2+3=5 1+2=3 0+1=1
andreareina 4y ago
This seems to be the paper https://academic.oup.com/mnras/article/517/4/5260/6779709 https://academic.oup.com/mnras/article/517/4/5260/6779709
delta_p_delta_x 4y ago
Astrophysical and cosmological simulations are often insightful. They're also very cross-disciplinary; besides the obvious astrophysics, there's networking and sysadmin, parallel computing and algorithm theory (so that the simulation programs are actually fast but still accurate), systems design, and even a bit of graphic design for the visualisations. Some of my favourite simulation projects: - IllustrisTNG: https://www.tng-project.org/ https://www.tng-project.org/ - SWIFT: https://swift.dur.ac.uk/ https://swift.dur.ac.uk/ - CO5BOLD: https://www.astro.uu.se/~bf/co5bold_main.html https://www.astro.uu.se/~bf/co5bold_main.html (which produced these animations of a red-giant star: https://www.astro.uu.se/~bf/movie/AGBmovie.html https://www.astro.uu.se/~bf/movie/AGBmovie.html) - AbacusSummit: https://abacussummit.readthedocs.io/en/latest/ https://abacussummit.readthedocs.io/en/latest/ And I can add the simulations in the article, too.
- froeb 4y ago
  Supernova simulations are especially interesting too. I have heard them described as the only time in physics when all 4 of the fundamental forces are important. The explosion can be quite finicky too. If I remember right, you can't get supernova to explode properly in 1D simulations, only in higher dimensions. This was a mystery until the realization that turbulence is necessary for supernova to trigger--there is no turbulent flow in 1D.

75 points by Amorymeltzer 4y ago

andrewflnr 4y ago

Whoa. I didn't know the accretion theory of Ia supernovae was dead, much less that it had been since 2011.

andreareina 4y ago

Wouldn't double detonation show up as variance in the brightness?

yencabulator 4y ago
Or widening of the peak. If one type Ia supernova goes 1,2,3,2,1, the sum of two could go 1+0=1 2+1=3 3+2=5 2+3=5 1+2=3 0+1=1

andreareina 4y ago

This seems to be the paper https://academic.oup.com/mnras/article/517/4/5260/6779709 https://academic.oup.com/mnras/article/517/4/5260/6779709

delta_p_delta_x 4y ago

Astrophysical and cosmological simulations are often insightful. They're also very cross-disciplinary; besides the obvious astrophysics, there's networking and sysadmin, parallel computing and algorithm theory (so that the simulation programs are actually fast but still accurate), systems design, and even a bit of graphic design for the visualisations. Some of my favourite simulation projects: - IllustrisTNG: https://www.tng-project.org/ https://www.tng-project.org/ - SWIFT: https://swift.dur.ac.uk/ https://swift.dur.ac.uk/ - CO5BOLD: https://www.astro.uu.se/~bf/co5bold_main.html https://www.astro.uu.se/~bf/co5bold_main.html (which produced these animations of a red-giant star: https://www.astro.uu.se/~bf/movie/AGBmovie.html https://www.astro.uu.se/~bf/movie/AGBmovie.html) - AbacusSummit: https://abacussummit.readthedocs.io/en/latest/ https://abacussummit.readthedocs.io/en/latest/ And I can add the simulations in the article, too.

froeb 4y ago
Supernova simulations are especially interesting too. I have heard them described as the only time in physics when all 4 of the fundamental forces are important. The explosion can be quite finicky too. If I remember right, you can't get supernova to explode properly in 1D simulations, only in higher dimensions. This was a mystery until the realization that turbulence is necessary for supernova to trigger--there is no turbulent flow in 1D.