# 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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### Is Earth's iron core kind of like a white dwarf?

Because Earth's iron core has iron atoms not bonded to one another but in a lattice where there is a sea of electrons and there are ionized iron atoms holding back from gravitational collapse of the ...
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### Mass formation of a neutron star Vs White dwarf

I have been researching the different outcomes of a star's death. I understand that the main factor is the star's mass at the end of its life, along with others such as its metallicity. Well, the ...
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### Luminosity and absolute magnitude relationship

Context : an exercise gives the temperature, mass, distance and apparent magnitude of Sirius B and asks to calculate its density. One key step of the calculation is to get the luminosity from the ...
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### Massive star evolution leading to white dwarf?

Is it possible that a star with an initial mass greater than $12 M_\odot$ loses so much mass in the giant phase that it eventually becomes a white dwarf? If it is possible, what constellation or ...
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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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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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1 vote
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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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### 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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