Thought experiments with neutron star

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?

Would the degenerate neutron pressure cause
explosion and neutron showers ?

Or, would it become non-degenerated NS ?

Or, would it recompose to back to iron-nickel
and their electrons, forming Fe-Ni white dwarf ?

--
Poutnik

Wise man guards the words he says,
as they may speak about him more, than about the subject.

On Fri, 27 Jun 2014 08:41:13 +0200, Poutnik wrote:

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?


Neutron degenerate matter would not be stable at pressures
other than that within a neutron star.

I would imagine that a reverse reaction to the formation,
which is essentially beta capture, would occur.

On 27/06/2014 2:41 AM, Poutnik wrote:

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?

Would the degenerate neutron pressure cause
explosion and neutron showers ?

Or, would it become non-degenerated NS ?

Or, would it recompose to back to iron-nickel
and their electrons, forming Fe-Ni white dwarf ?

The material stays in the form of neutrons because of gravity. If there
isn't enough gravity, then the neutrons will go flying off in a
spectacular explosion. I don't think it will turn back into Nickel or
Iron, but rather back into Hydrogen. All of the neutrons will go their
separate ways, so that would mean they would revert back to their
simplest states which is one neutron which would decay into a proton and
an electron, which is of course hydrogen.

Yousuf Khan

Dear Poutnik:

On Thursday, June 26, 2014 11:41:13 PM UTC-7, Poutnik wrote:
....
What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?

More than likely the same thing that we find on the surface of a neutron star... nickel and iron is formed. The distances between neutrons is low enough, that maximum stability can be obtained.

Would the degenerate neutron pressure cause
explosion and neutron showers ?

If we had two neutron stars collide "en passant", maybe.

Or, would it become non-degenerated NS ?

"NS"?

Or, would it recompose to back to iron-nickel
and their electrons, forming Fe-Ni white dwarf ?

I'd go for a Dark dwarf, since there'd be little reformation after a few million years after the "breakup".

But then if this Universe is the inside of a black hole, and this black hole started with a massive neutron star, then that would say the neutron when presented with a new spacetime, no matter how dense, mostly reverts to protons and electrons.

David A. Smith

On Fri, 27 Jun 2014 08:41:13 +0200, Poutnik wrote:

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?


It is analogous, thermodynamically, to the case of diamonds.

Diamonds are formed under high pressure conditions. When brought
to STP conditions, a diamond is energetically unstable and will
revert to a lower energy form. (Assuming no oxygen is present).

Thermodynamics, however, does not contain the time variable and makes
no prediction on the amount of time required for the reversion.

A related question would concern the energy difference between,
let's say, a gram of matter within a neutron star and the same
matter under "ordinary" conditions.

On 27.06.14 8:41, Poutnik wrote:

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?

Would the degenerate neutron pressure cause
explosion and neutron showers ?

Or, would it become non-degenerated NS ?

Or, would it recompose to back to iron-nickel
and their electrons, forming Fe-Ni white dwarf ?

The only reason, that degenerate matter does stay in one place,
is gravity.
Take away the gravity and atoms disengage with the force of a
hydrogen bomb explosion.

Dne 27.6.2014 9:07, Frank Colessi napsal(a):
On Fri, 27 Jun 2014 08:41:13 +0200, Poutnik wrote:

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?


Neutron degenerate matter would not be stable at pressures
other than that within a neutron star.

I would imagine that a reverse reaction to the formation,
which is essentially beta capture, would occur.

I suppose similar, it it could be interesting
to watch history of energy per nucleon
during formation and destoring of NS matter forms.

--
Poutnik

Wise man guards the words he says,
as they may speak about him more, than about the subject.

Dne 27.6.2014 16:29, Yousuf Khan napsal(a):
On 27/06/2014 2:41 AM, Poutnik wrote:

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?

Would the degenerate neutron pressure cause
explosion and neutron showers ?

Or, would it become non-degenerated NS ?

Or, would it recompose to back to iron-nickel
and their electrons, forming Fe-Ni white dwarf ?

The material stays in the form of neutrons because of gravity. If there
isn't enough gravity, then the neutrons will go flying off in a
spectacular explosion. I don't think it will turn back into Nickel or
Iron, but rather back into Hydrogen. All of the neutrons will go their
separate ways, so that would mean they would revert back to their
simplest states which is one neutron which would decay into a proton and
an electron, which is of course hydrogen.


Hmmm.

It would close the cycle
hydrogen - helium - carbon ....... iron
back to hydrogen.

Iron has lower energy per nucleon than hydrogen,
even lowered by gravitation potential of NS.

Is theoretical energy to "dig out" matter out from NS
high enough to return energy per nucleon to original hydrogen ?


--
Poutnik

Wise man guards the words he says,
as they may speak about him more, than about the subject.

Dne 27.6.2014 16:59, dlzc napsal(a):
Dear Poutnik:


Or, would it become non-degenerated NS ?

"NS"?

Neutron Star.



--
Poutnik

Wise man guards the words he says,
as they may speak about him more, than about the subject.

Dne 27.6.2014 19:06, Frank Colessi napsal(a):
On Fri, 27 Jun 2014 08:41:13 +0200, Poutnik wrote:

What would happen to a "piece of neutron star",
if it was by whatever process cut out from NS,
and had low enough mass ?


It is analogous, thermodynamically, to the case of diamonds.

Diamonds are formed under high pressure conditions. When brought
to STP conditions, a diamond is energetically unstable and will
revert to a lower energy form. (Assuming no oxygen is present).

This is clear, as I am a chemist.

But how does compare energy per nucleon in neutron star,
compared to hydrogen - iron scale of these energies ?

And how it would change if digged out ?



Thermodynamics, however, does not contain the time variable and makes
no prediction on the amount of time required for the reversion.

I agree, it is similar to chemistry, but not the topic now.

A related question would concern the energy difference between,
let's say, a gram of matter within a neutron star and the same
matter under "ordinary" conditions.

Yes, as stated above.

--
Poutnik

Wise man guards the words he says,
as they may speak about him more, than about the subject.