How dense would neutron matter be?

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    Matter Neutron
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Discussion Overview

The discussion revolves around the density of neutron matter, particularly in the context of hypothetical scenarios involving neutrons contained in a bottle versus the conditions found in neutron stars. Participants explore the implications of neutron behavior and interactions with materials.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions whether a bottle full of neutrons would weigh less than a bottle of protons, suggesting a comparison of densities.
  • Another participant explains that neutrons in a neutron star are held together by the Pauli exclusion principle, indicating that neutron matter can reach extreme densities without collapsing into black holes.
  • A participant challenges the initial question by stating that containing particles in a bottle differs from discussing the density of a substance, emphasizing the role of gravitational forces in neutron stars versus the constraints of a bottle.
  • There is a query about the feasibility of neutrons remaining in a bottle, raising concerns about their ability to escape through the walls.
  • One participant elaborates on the behavior of thermal neutrons, noting that they can diffuse through bottle walls and interact with nuclei, while protons behave differently due to repulsion and capture processes.
  • Another participant reiterates the concern about neutrons escaping the bottle, questioning whether they would pass straight through the walls if sealed.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility of containing neutrons in a bottle, with some questioning the practicality of the scenario and others providing technical explanations of neutron behavior. The discussion remains unresolved regarding the initial question of density comparisons.

Contextual Notes

Participants highlight limitations in the scenario, such as the assumptions about containment and the differences between gravitational forces in neutron stars and the forces acting on particles in a bottle.

hurricane89
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if you took plain neutrons, and put them in a bottle would a bottle full of neutrons weigh less than a bottle of bear protons with no electrons arround?
 
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You'd have to squeeze them to change the density any. In a neutron star (that's a collapsed star that started out more massive than the sun, and ended up the same size as some asteroids--10ish km in diameter) neutrons at the core of the star avoid collapse via the Pauli exclusion principle. In other words, it's about as dense as matter can get without turning into whatever black holes are made of.

Average densities are tabulated in the link below:
http://hypertextbook.com/facts/1998/AnthonyColgan.shtml
 
I don't think your question matches the title. Putting particles in a bottle is a different situation than the density of a substance. Certainly the inward force provided by glass walls is much smaller than the inward force of gravity from a neutron star.
 
Why would the neutrons stay in the bottle?
 
Thermal neutrons, which are not sensitive to the Coulomb forces in atoms or to the Pauli exclusion principle (except inside nuclei), will diffuse through the bottle walls until they are captured by nuclei that usually go through (n,gamma) reactions. Sometimes they go through (n,alpha) reactions like neutron capture on boron-10. Protons, which are repelled by other other protons or by nuclei, will stop in the bottle walls and capture electrons from the other nuclei. Hydrogen atoms, being small, can diffuse into the bottle walls (or back into the gas as hydrogen) and cause hydrogen embrittlement, especially in steels. This is a concern in the development of the hydrogen economy. To get a sense of the density of a proton gas, it is now possible to buy capacitors that hold a Coulomb of (electron) charge. But a mole (gram molecular weight) of protons contains 96,000 Coulombs of charge.
 
Bob S said:
Thermal neutrons, which are not sensitive to the Coulomb forces in atoms or to the Pauli exclusion principle (except inside nuclei), will diffuse through the bottle walls until they are captured by nuclei that usually go through (n,gamma) reactions. Sometimes they go through (n,alpha) reactions like neutron capture on boron-10. Protons, which are repelled by other other protons or by nuclei, will stop in the bottle walls and capture electrons from the other nuclei. Hydrogen atoms, being small, can diffuse into the bottle walls (or back into the gas as hydrogen) and cause hydrogen embrittlement, especially in steels. This is a concern in the development of the hydrogen economy. To get a sense of the density of a proton gas, it is now possible to buy capacitors that hold a Coulomb of (electron) charge. But a mole (gram molecular weight) of protons contains 96,000 Coulombs of charge.

so the neutrons wouldn't even be able to stay in the bottle because theyde just go through the walls? also, do you mean through like a path straight through the walls of the bottle?
 
alxm said:
Why would the neutrons stay in the bottle?

if you seal it they shouldn't escape right
 

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