# Questions tagged [white-dwarfs]

The final evolutionary state of stars whose mass is not high enough to become a neutron star or black hole.

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### Does the wave function of localized s-orbitals radius reduce under extreme solid-state pressures prior to degeneracy?

Under extreme conditions not found in nature, say low temperature solids that are under extreme pressures* prior to collapse into degenerate matter states, does a localized s-orbital radius reduce ...
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### Paradox about white dwarfs and ionization

I am facing a dilemma. The fact that matter is ionized allows ions and electrons to be much closer together than they are in atoms (Bohr radius $a = 0.5 \cdot 10^{− 10} \mathrm{m}$), and the result is ...
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### Modelling a fully relativistic White Dwarf Star

I am trying to model a fully relativistic white dwarf using different central densities. Using the below equations: $\frac{dP}{dm} = -\frac{Gm}{4\pi r^4}$ $\frac{dr}{dm} = -\frac{1}{4\pi\rho r^2}$ and ...
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### Is a small fragment of a white dwarf stable? [duplicate]

Assuming it is somehow possible to get a small piece of a white dwarf (maybe a dice) and this piece escapes into free space. Would that piece of white dwarf matter keep its density/state, or would it ...
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### Luminosity of a white dwarf

Why in an H-R diagram the white dwarfs are at the bottom left? I understand that they would have a high temperature when they are formed, and so at that instant shouldn't they have a high luminosity ...
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1 answer
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### Where are the high mass White Dwarfs that are going to create type 1a SN

The mass distribution of WD stars is explained at Why is the white-dwarf mass distribution highly peaked?. However this mass distribution shows very few stars that are about to exceed the WD limit of ...
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### What fundamental force is at play in electron degeneracy pressure? [duplicate]

For example 2 electrons repel each other because they experience electromagnetic force, matter particles attract each other because they exert gravitational force on each other, fusion is possible ...
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### Could a sufficiently massive Dyson Sphere under very specific conditions depend solely on electron degeneracy pressure for structural integrity?

Stuck in an argument. I claim this is theoretically possible: Provided you could build a type 1 Dyson Sphere, made from a supposed material that rivals the structural integrity of a white dwarf, i.e. ...
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### Would a Dyson sphere face physical limits faced by white dwarves?

During a recent online discussion, one of the participants made the claim that a Dyson sphere would be limited in mass by the Chandrasekhar limit. Attempts to solicit evidence for this claim were ...
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### How to get the Chandrasekhar Limit from a plot?

at the moment I am trying to understand, how to obtain the Chandrasekhar mass limit from a plot like shown above. Because for $n$ = 3, the mass is independent of the radius of the white dwarf. But in ...
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### What is the theoretical lower mass limit for a white dwarf?

This question in inspired by this other one, which asks what is the theoretical lower mass limit for a gravitationally stable neutron star (not the Chandrasekhar limit which is the upper mass limit ...
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### What is the Chandrasekhar-Friedman-Schutz (CFS) instability, exactly?

I am confused as to what the Chandrasekhar-Friedman-Schutz (CFS) instability is, exactly. It seems to refer to this paper by Chandrasekhar, but I do not think this paper covers the full instability. ...
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### How does gravity acts on the electrons to collapse a neutrons star or white dwarfs against the degeneracy pressure?

if electrons is considered as quantum particle in case neutron star (alluding to quantum statistics) how does gravity makes the star collapse? considering the fact that electrons are quantum particles ...
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4 votes
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### What's the transition from "metal" to "electron-degenerate matter" look like?

Question: Say that we had metallic water and compressed it until it qualitatively resembled the state of matter in a white dwarf: what would that transition look like? Background (revised to be ...
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### What does a redder galaxy mean?

I've been reading on the subject and I've repeatedly read that red galaxies are those with redder stellar populations which means (according to my readings) older star populations, with low star ...
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### Where does the energy for electron degeneracy pressure come from?

I just watched a web video about white dwarf stars. It mentions that the star’s electrons flow among the degenerate matter. Since most of the electrons can’t be in the lowest state, due to Pauli’s ...
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