J. Schaffner Bielich - Probing Dense Matter in Neutron Stars

Speaker: Juergen Schaffner-Bielich
Abstract: Neutron Stars are born in core-collapse supernovae being the endpoint of stellar evolution of massive stars. Their extreme properties allow for the study of dense matter in the sky. In recent years the advancement of astrophysical observations has been so tremendous that the properties of neutron stars can be constrained nowadays to an unprecedented level. I will summarize the basic observations of neutron star masses from pulsar data, the constraints on radii from x-ray measurements, and the first detection of gravitational waves from a neutron star merger. On the other hand, I will discuss the nuclear and particle physics aspects of the equation of state of neutron star matter which is firmly limited at low and high energy densities. Chiral effective field theory puts a stringent constraint up to about saturation density for pure neutron matter. Perturbative QCD calculations narrow the equation of state at ultimately high densities. Finally, I will address the possible existence of new phases in the core of neutron stars which can be revealed from the mass-radius relation of neutron stars. I will argue that it is in principle impossible to rule out phase transitions in neutron stars from observations based on general relativity alone.
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[@bryandraughn9830]

This is so much more informative and detailed than other KZbin sources. I love it!

[@thomasgade226]

lecture begins @6:00

[@PaulHigginbothamSr]

Since the neutron star can withstand the bounce upon forming by rebounding to a higher state of equation then they can be much larger than the smallest ones we see. However some up them upon cooling do drop into nothingness of a black hole. Also spin angular momentum also seems to aid the largest size. So the balance is exquisite. The fact that they were theorized soon after the discovery of the neutron means they do need added more abundantly to heavier elements to keep the protons from flying apart with so much repulsion. In fact why they gain so much energy upon fission and why less and less energy is obtained when heavier elements fuse. My guess is most of the heavier elements in the Earth's crust was from a kilonova in the cloud forming the solar system. Thus the range of rare earths seeming to be so numerous was from decaying neutron star collision fragments and had to cool enough to collapse into the solar system. All this means I wonder how rare life is in the universe.

[@martinkaufmann4067]

great!

[@georgewaters6424]

too many adds, wont be coming back!