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2answers
44 views

Can a binary star system create a stationary black hole?

Research over the last 200 years suggests that half or more of visible stars are part of multiple star systems. I apologise for the number of assumptions in my question but, because of the numbers of ...
2
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1answer
57 views

Can we estimate the size of a neutron star based on direct observation? [duplicate]

Are there any neutron stars near enough for astronomers to get a good size-estimate, based on direct observation? I know that there are many theories regarding what happens inside neutron stars, but I ...
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0answers
26 views

Can the Higgs field have a different value in the neutron stars?

What I know: 3 components of the Higgs field is coupled to the W+, W- and Z fields. The fourth component is determined by the energy minimum in the "mexican hat" potential. The W and Z bosons decay ...
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2answers
122 views

Can astronomers observe neutron stars optically?

Are there any neutron stars near enough for astronomers to observe them optically? If not, then how close are we to having the technology to do so?
2
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3answers
99 views

Size and density of neutron stars

Most of the books which I looked at give approximately 10 km as the radius of a neutron star. Just yesterday I looked at a book by Dave Goldberg titled The Universe In the Rearview Mirror (2013) which ...
0
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1answer
58 views

Qualitative picture or reference for a Lemaître's Cold Big Bang theory

Warning: please, consider this question to be motivated by historical curiosity or as an exercise in model-building. I believe this cannot be considered non-mainstream physics as it was very much ...
1
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1answer
34 views

Why don't degenerate gases expand from heat?

Degenerate gases are excellent conductors of heat. However, the fermions that compose the gas will not expand outwards due to heat, except in incredibly high temperatures. Why is this? Does it have ...
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1answer
67 views

Are black holes really just neutron stars? [closed]

I was curious if it would be possible for blackholes to actually just be neutron starts that are so large that they trap light and gain mass from nearby objects. If this were true that would mean that ...
4
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1answer
103 views

Gravitational waves from neutron star - neutron star merger

How is neutron star-neutron star merger different from Black Hole-Black Hole merger and what information can be extracted from gravitational waves emitted by these processes?
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0answers
36 views

How do I make a slowly rotating neutron star using fortran code?

I make a slowly rotating neutron star code but I am little bit confuse, when I solved the coupled differential equation using runga-kutta 4th order method. These coupled differential equations as ...
2
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1answer
31 views

Can we apply no hair theorem to neutron stars?

As neutron stars are composed of neutrons only and we can't know where the neutron comes from (eg: from what atoms), does neutron stars also fulfill no hair theorem?
2
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1answer
34 views

Pulsar-white dwarf binary

In the paper from Hulse & Taylor 1975 on the first discovery of a pulsar in a binary system, they conclude that the companion to the pulsar must be a compact object, probably a neutron star or ...
2
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1answer
64 views

Is it possible to tidally lock a neutron star?

As I know, neutron stars are almost perfect sphere and no net moments, does it mean it is not possible to tidally lock it?
0
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1answer
87 views

The inside of of a black hole

I am looking for a confirmation (or correction) of my thinking about the nature of the black holes. As I am not a physicist and only a physics enthusiast, my understanding is probably very simplified ...
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1answer
37 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 ...
2
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2answers
71 views

What would happen if I gathered stellar sized masses of iron?

Lets say I had a bag that when turned upside would start pouring out iron shavings and never ever stop. Viola, there's my infinite source of iron. Now, lets say I just continued to dump this iron ...
0
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2answers
121 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 ...
1
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1answer
213 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 ...
4
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1answer
162 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
42 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 ...
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4answers
145 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 ...
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2answers
42 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 ...
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2answers
148 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
votes
1answer
87 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 ...
12
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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 ...
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3answers
154 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 ...
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2answers
83 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 "...
3
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1answer
184 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 ...
4
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3answers
570 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
85 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
votes
2answers
81 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
76 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
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1answer
136 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 ...
1
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0answers
56 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
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1answer
117 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 ...
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0answers
47 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
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1answer
3k 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
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1answer
68 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
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1answer
161 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 v^2=\...
2
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2answers
229 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 ...
1
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2answers
343 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 scale?...
2
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3answers
450 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 ...
3
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1answer
539 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 ...
4
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1answer
64 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 ...
1
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1answer
70 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
votes
2answers
462 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.
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1answer
2k 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 process?...
3
votes
1answer
120 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:- ...
4
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1answer
273 views

Equation of State and Neutron star

I'm searching for equation of state books, with references to neutron star and ultra-dense matter.
15
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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 ...