All Questions
Tagged with n-body-simulations cosmology
13 questions
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What is the point of approximate Large Scale Structure simulation with neural networks?
People use N-body simulations to compute Large Scale Structure (LSS). To use this method you need to make assumptions about the underlying physics, e.g. the parameters of the Universe expansion, the ...
- 153
7
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1
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557
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Large scale structure/Single galaxy simulation on GPU
I noticed that most of the tools for cosmological simulation (e.g. large scale structure or single galaxy evolution) are based on GADGET. It only allows to use CPU.
Why not GPU? What is the main ...
- 153
3
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1
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64
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RAMSES fine multigrid Poisson solver fails to converge?
I am working on setting up N-body simulations of galaxy mergers. The initial conditions are generated from the DICE code, and looking at them, they seem very realistic. Unfortunately, when I let ...
- 151
5
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1
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What is Gravitational softening length?
I was reading the Aquarius simulation preprint (Springel et al. 2008) The Aquarius Project: the subhalos of galactic halos as a reference for my internship. I came across the term Gravitational ...
3
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0
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35
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Mass resolution in cosmological simulations [duplicate]
I've been reading papers about different cosmological simulations and they all talk about the "mass resolution" of those. Can someone please explain what does "mass resolution" ...
- 31
4
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1
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94
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How to locate helpful and instructive books and resources about numerical methods in cosmology?
I am interested in the hydrodynamical and N-body simulations, and I want to use simulation results to examine the theoretical models.
Hence I am searching for some helpful and instructive books and ...
- 451
2
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0
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54
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What are the one-dimensional observables that can reveal the matter clustering properties of the Universe?
As we all know, the distribution of galaxies, which depend on the spatial coordinates, can help us understand the large-scale structure of the Universe. We can measure the distribution of galaxies ...
- 451
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93
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Would it be a good idea to dockerize softwares in order to conduct hands-on tutorial sessions? [closed]
I am going to organize a tutorial in which I intend to train students on semi numerical simulations for reionization. Is it a good idea to supply use Docker to supply the codes?
What do you think ...
- 89
2
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1
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121
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Why is the boundary of friends-of-friends (FOF) halo corresponding to iso-density contour?
The friends-of-friends algorithm (hereafter FOF) is commonly used to find halos in cosmological simulations. (For more information, please refer to here and here)
I found that some literature argues ...
- 451
12
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2
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3k
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Why do people choose 0.2 as the value of linking length in the friends-of-friends algorithm?
The friends-of-friends algorithm (hereafter FOF) is commonly used to find halos in cosmological simulations. And FOF depends on only one parameter, linking length, $l_\mathrm{link}=b \left(\frac{V_u}{...
- 451
4
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2
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878
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'Little h' usage in cosmological simulations
I am running a cosmological simulation and am having some trouble putting things into code units. The physical distance units in my simulation are in terms of $\text{Mpc/h}$, where $h$ is the ...
- 141
3
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1
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407
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Difference between 3D real space and 3D redshift space?
With regards to cosmological simulations (e.g., N-body dark matter only simulations), I've seen people talk about the positions of objects (halos, galaxies) in the simulation in terms of 3D real space ...
- 723
2
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1
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488
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Mass resolution
Can someone define mass resolution in terms of cosmological simulations such as the millennium simulation? Is it just the smallest mass that a dark matter particle can have and still be detected by ...
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