It's my understanding the general mechanism of core collapse involves the adiabatic constant of the material, gamma. This is the exponent in the relation P V^(gamma) = constant.
For a normal, non-relativistic gas in which the particles have no internal degrees of freedom, gamma is 5/3. As a gas becomes more relativistic, and as photon pressure becomes more important, gamma declines toward 4/3.
For gamma = 4/3, a self-gravitating gas will be marginally stable: the energy needed to compress a sphere of the gas will be equal to the gravitational potential energy liberated by the compression. So, any effect that pushes gamma below 4/3 makes it unstable against collapse.
In a conventional core collapse SN this is photodissociation of nuclei, where energy gets soaked up in breaking apart nuclei into alpha particles and then free nucleons. In a pair-instability SN, this is increasing conversion of photons to electron-positron pairs.
I just want to live long enough for space telescopes to evolve exponentially to observe kilonovas in the visual spectrum
I mean laser interferometers are an amazing advancement but just imagine seeing an earth-sized chunk of gold pop out of a kilonova (probably not my lifetime but eventually a human will see it happen)
Thank goodness this administration did not frack with Nancy Grace Roman Telescope, I thought the name alone would make them cancel it or rename it after him, wait maybe I shouldn't even mention that idea...
I like to think there's a solid argument against dark forest that even if you can destroy other intelligent systems, then hidden intelligent cautious systems may exist and see evidence of what you've done, so there's a potential consequence to destroying every intelligent system you identify.
And then also (maybe this is absurd) isn't there something intrinsic in intelligence to want to avoid conflict and desire peace?
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[ 8.8 ms ] story [ 33.3 ms ] threadhttps://en.wikipedia.org/wiki/Pair-instability_supernova
For a normal, non-relativistic gas in which the particles have no internal degrees of freedom, gamma is 5/3. As a gas becomes more relativistic, and as photon pressure becomes more important, gamma declines toward 4/3.
For gamma = 4/3, a self-gravitating gas will be marginally stable: the energy needed to compress a sphere of the gas will be equal to the gravitational potential energy liberated by the compression. So, any effect that pushes gamma below 4/3 makes it unstable against collapse.
In a conventional core collapse SN this is photodissociation of nuclei, where energy gets soaked up in breaking apart nuclei into alpha particles and then free nucleons. In a pair-instability SN, this is increasing conversion of photons to electron-positron pairs.
I mean laser interferometers are an amazing advancement but just imagine seeing an earth-sized chunk of gold pop out of a kilonova (probably not my lifetime but eventually a human will see it happen)
Thank goodness this administration did not frack with Nancy Grace Roman Telescope, I thought the name alone would make them cancel it or rename it after him, wait maybe I shouldn't even mention that idea...
* https://science.nasa.gov/mission/roman-space-telescope/
* https://en.wikipedia.org/wiki/Nancy_Grace_Roman_Space_Telesc...
And then also (maybe this is absurd) isn't there something intrinsic in intelligence to want to avoid conflict and desire peace?
[1] https://en.wikipedia.org/wiki/Spontaneous_combustion