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0
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1answer
20 views

Is the magnetic dipole moment in charged particles the more survivable property than the electric charge?

After asking about Which of the properties of particles are intrinsic properties and why? it was commented "Charge, spin, lepton number, baryon number definitely. Mass maybe." and "is magnetic dipole ...
0
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2answers
101 views

A Neutron Star and an Atom are Similar [closed]

In an earlier question I asked if photons could exist without atoms. Is a neutron star's residual light released similar to an exited atom the difference is gravity hold in the electrons in the star ...
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3answers
125 views

When a neutron star accumulates enough mass, does a black hole start at its center?

With less dense bodies, such as the earth and the sun, the center has less gravity/density (since there's an equal amount of mass surrounding the center, pulling out on it from all directions). Does ...
0
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1answer
185 views

Can a perfect insulator, i.e. matter devoid of all electrons conduct electricity?

Few weeks ago an article on Nautilus was published on Neutron stars. After reading that, a question was asked by a friend of mine. He asked if matter in neutron star would be able to transfer ...
2
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1answer
148 views

What is the largest possible mass for a stable planet made of iron?

Consider a large spherical planet made of pure iron. Think of something similar to Mercury or Earth without its mantle, only much bigger, though those planets have elements other than iron mixed in ...
1
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1answer
57 views

Complex structures bound by nuclear forces ( nuclear molecules ?)

This is very hypothetical question. Consider all chemistry (even bio-chemistry) is just physics of valence electrons. Because solutions of Schroedinger equation for system of electrons and nuclei are ...
4
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3answers
466 views

Can a neutron star compress until it's converted to a black hole?

The Universe's densest objects are black holes. In the second place, there are neutron stars. So, if a neutron star compresses to its Schwarzschild radius, would it appear as a black hole? That black ...
3
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1answer
215 views

Equation of State and Neutron star

I'm searching for equation of state books, with references to neutron star and ultra-dense matter.
4
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1answer
114 views

Why do neutron stars have solid crusts?

A long time ago I read that neutron stars have a solid crusts that are several orders of magnitude harder/stronger than alloys here on the Earth. So how is this possible ? A neutron star has a ...
0
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1answer
38 views

How can one interaction influence the way another interaction generates mass?

This question arose as a follow-up of this one and applies generally to all interactions and all ways to generate mass. To make it clear, I take here the example of the neutron, whose mass is in ...
-1
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4answers
96 views

What could break up a neutron star?

Beside the obvious answer black hole, is there anything else? Could a nearby supernova blow it away/apart? Or any sort of (theoretically intense enough) field? I guess an electric field is out of the ...
9
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3answers
305 views

How to cut a stone on a White Dwarf?

I've heard that white dwarf stars are extremely dense and hard. So, if I had a piece of white dwarf matter, would it be possible to cut it (or otherwise) into a custom shape? How could one do that?
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2answers
34 views

Can we create sheet of neutron

I want to know are there any theory or technology to create a neutron matter like neutron star on earth. Even a tiny thin sheet like graphene And how heavy it is if we create 1x1 sqmm of neutron ...
14
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1answer
2k views

What is the theoretical lower mass limit for a gravitationally stable neutron star?

I ask here intentionally not for the size of the smallest possible observed size of neutron stars, which corresponds approximately to the well-known Chandrasekhar-limit for the upper limit of the ...
2
votes
1answer
321 views

What is meant by a “stiff” or “soft” equation of state (wrt neutron stars)?

I am currently trying to understand the history of the development of the equations of state and structure of neutron stars. In my textbook, I frequently encounter phrases such as "The ...
8
votes
3answers
488 views

Neutron stars and black holes

The official limits for a neutron star is $1.4 - 3.2\;M_\odot$. But I read that the limit depends on the particular structure of a star to estimate which mass it must have. I also read that neutron ...
6
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2answers
101 views

Do the magnetic moments of neutrons mutually align to produce the magnetic field and emission beams of a pulsar and/or magnetar?

In this graphic of a pulsar the emission beams are at the north and south poles of the neutron star's magnetic field. I've read that the Earth's magnetic field is produced by a dynamo effect, whereby ...
7
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1answer
70 views

Do neutron stars emit stellar flares?

Since stellar flares are formed from the magnetic energy of a star, is it probable to assume that neutron stars can emit stellar flares as well? If so, how would the super fluid material of the star ...
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2answers
1k views

Is a neutron star basically an isotope?

Since a neutron star is basically just a vast amount of densely packed neutrons, I was wondering whether those neutrons form a single "atom" (of atomic number zero) or whether they are further apart ...
14
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3answers
797 views

How would neutron matter appear to the naked eye?

Neutron matter is matter comprised entirely of neutrons, as it exists in neutron stars. Most optical phenomena encountered in everyday life, such as light reflection and spectral absorption (i.e. ...
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0answers
52 views

Thomas precession and neutron star accretion discs

Assuming, based on this wikipedia article Accretion Discs That accretion discs surrounding neutron stars are composed of a gas and / or plasma. That the accretion disc material can achieve a ...
0
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2answers
50 views

How much energy is released per unit mass from depressurizing degenerate matter?

A neutron star remnant consists mostly of neutron degenerate matter. If you happened to suddenly have 1 kg of it in your lap without the pressure necessary to keep it degenerate, I suppose it would ...
4
votes
3answers
415 views

What is the binding energy of a neutron star?

Neutrons which constitute a neutron star have a rest mass that is greater when separated from the star because they are bound with a certain potential energy. This potential energy causes the system ...
3
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2answers
76 views

How can we determine the internal structure of a star from distance?

See here for the discussion leading to this question. In essence, I was wondering whether there were methods to differentiate between a star destined to become neutron star and a star destined to ...
0
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2answers
65 views

What do moles and moles of various subatomic particles gathered together look like?

I wonder whether it is even possible to find the answer. If it is impossible to find out, why? Do moles of neutrons basically look like a neutron star? If so, what does one look like? How about ...
2
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1answer
68 views

Will the rotation of a neutron star prevent it becoming a Black Hole?

This question, to me anyways, is basically a balancing act between 2 possibly opposing effects. Take a neutron star with just too small a mass to overcome it's degeneracy pressure, failing to ...
1
vote
1answer
113 views

Do neutron stars produce sound?

I've watched a video on youtube about neutron stars as called (pulsar) and it claims that pulsars produce this sound. then i found that they produce radio waves which can be converted to sound. Radio ...
0
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0answers
53 views

How stable is a tablespoon of neutrons once removed from a neutron star? [duplicate]

I've often heard public lectures describing the degenerate, exotic matter left behind after a star collapses but fails to go supernova; one that has found its way to become a neutron star. The speaker ...
1
vote
1answer
95 views

Uncertainty principle within a neutron star or black hole

Take the time-energy uncertainty relation, $\Delta$$E$$\Delta$$T$$\ge$$\hbar/2$. My question is based on my confusion about the effect this relation may have within the interior of a highly ...
1
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0answers
43 views

Is there a numerical calculation for black hole - neutron star merges?

I think it might be even a more frequent event as the black hole merges. It would be similar to the black hole merges in the gravitational wave spectrum, but it could have a very clear neutrino and ...
4
votes
1answer
2k views

What is the pressure at the center of the Earth? (Or a neutron star)

The center of the Earth has microgravity and is thought to be solid and almost 6000 degrees hot. What is the pressure like there? The confusing thing, for the common man I suppose, is that there's no ...
1
vote
1answer
61 views

What are some current models for neutron star core? [closed]

How are neutron star cores described today, do we use models of superfluidity/superconductivity for instance?
0
votes
1answer
150 views

Neutron star: escape velocity

The textbook from which I teach physics at the end of secondary school calculates the escape velocity at the surface of a non-rotating neutron star Newton-style using $\frac{1}{2}\cdot m\cdot ...
2
votes
2answers
186 views

Neutron star: free fall acceleration

The textbook from which I teach physics at the end of secondary school, has a question about a neutron star: $M_{star}=1.4\cdot M_{sun}$, radius 15km. "Calculate the free fall acceleration at the ...
22
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5answers
4k views

Can there be Electron and/or Proton Stars?

What happens to all of the electrons and protons in the material of a neutron star? Could there ever be an electron star or a proton star?
2
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3answers
351 views

Violation of Pauli exclusion principle

From hyperphysics (emphasis mine): Neutron degeneracy is a stellar application of the Pauli Exclusion Principle, as is electron degeneracy. No two neutrons can occupy identical states, even under ...
1
vote
2answers
251 views

Why are neutron stars mostly composed of neutrons?

I understand that it is due to electron capture $(p + e \rightarrow n + v_e)$. My precise question is: What are the conditions needed for a star core to start undergoing this process at a large ...
49
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9answers
3k views

Do all black holes have a singularity?

If a large star goes supernova, but not enough mass collapses to form a black hole, it often forms a neutron star. My understanding is that this is the densest object that can exist because of the ...
9
votes
4answers
3k views

How do neutron stars burn? Is it decay or fusion or something else?

What makes a neutron star burn, and what kind of fusion/decay is happening there? What is supposed to happen with a neutron star in the long run? What if it cools, then what do the degenerated matter ...
1
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0answers
50 views

For gravitational wave from twin stars, how was the tidal effect counted?

As the primary indirect evidence, the work on calculating the rotational slow down earned the 1993 Nobel prize. However, I cannot find any where mention how the work deal with the tidal effect. Are ...
3
votes
1answer
105 views

Collisions of celestial objects

When massive, spherical celestial objects collide, how long does it take for the objects to coalesce into a new, larger, spherical entity under the influence of gravity? Examples of the above:- ...
9
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4answers
824 views

Do neutron stars reflect light?

The setup is very simple: you have a regular ($1.35$ to $2$ solar masses) evolved neutron star, and you shine plane electromagnetic waves on it with given $\lambda$. Very roughly, what shall be the ...
2
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2answers
217 views

Position of Neutron Stars in H R diagrams

Why is that neutron stars are never depicted in a Hertzsprung-Russell diagram? They can be placed in the bottom left corner but you will never find any diagram in literature showing neutron stars.
0
votes
2answers
103 views

Regarding binary systems (with pulsars)

Are binary systems (in case of stars and other celestial bodies) more favorable than independent existence? I've been going through an article regarding pulsars, where it was stated that 'many pulsars ...
9
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1answer
3k views

What happens to atoms inside a black hole?

Black holes have very high gravitational force that tends to crush everything. So as we know atoms in a molecule have inter-atomic spacing between them and further electrons also revolve at a certain ...
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2answers
2k views

What would happen to a teaspoon of neutron star material if released on Earth?

I've read on NASA's page on neutron star that one teaspoonful of that star would weigh over 20 billion tonnes on Earth. If it was somehow possible to bring it to earth would it: Burn and disappear ...
10
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1answer
1k views

What happens to Protons and Electrons when a Neutron star forms?

What happens to Protons and Electrons when a Neutron star forms? At some point gravity overcomes the Pauli Exclusion Principle ( I assume) and they are all forced together. What happens in the ...
7
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3answers
739 views

What allows the modified Urca process to work at lower density than direct Urca in neutron star cooling?

The dominant method of neutron star cooling is neutrino emission. There are two regimes usually presented, the "direct Urca" and "modified Urca" processes, each of which are sequences of neutron decay ...
12
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3answers
650 views

How does the Pauli exclusion principle create a force in degenerate matter?

My understanding is that when it comes to forming a white dwarf, it is the electron degeneracy pressure, due to the Pauli Exclusion Principle, preventing collapse in of the white dwarf. If the ...
31
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6answers
9k views

How come neutrons in a nucleus don't decay?

I know outside a nucleus, neutrons are unstable and they have half life of about 15 minutes. But when they are together with protons inside the nucleus, they are stable. How does that happen? I got ...