Talk:Protostar

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What is the k in the formula? —Sverdrup(talk) 12:24, 22 Feb 2004 (UTC)

It is ofcourse Boltzmanns constant. :-) —Sverdrup(talk)

[edit] It's hard to keep up.

New data coming and it may well have something to say about the nature of Population III Stars:

http://www.nasa.gov/lb/vision/universe/starsgalaxies/xmm_magnetic_starbirth.html

http://arxiv.org/abs/astro-ph/0503029

X-ray telescopes are also revealing a higher-than-expected concentration of iron in the early universe.

[edit] Confusing statements

"Whatever the source of the disturbance, if it is sufficiently large it may cause the force due to gravity to become greater than the force due to thermal kinetic energy within a particular region of the cloud." - from paragraph 2, is confusing. Someone reword this please JustShin 02:11, 23 May 2007 (UTC)

JustShin: I just made an attempt at rewording and clarifying the sentence you mentioned. Hope this makes it clearer. MHD (talk) 11:06, 28 November 2007 (UTC)

The article states that kinetic energy is balanced by potential energy. It does not make sense. In fact according to virial theorem, for a bound state in equilibrium kinetic energy should be just half of the negative of potential energy. We may state that inward gravitational force is balanced by outward pressure.

In fact, the potential energy (that tries to contract the cloud) is counteracted not only by kinetic energy, but also by so-called turbulent pressure. I agree that a statement in the direction of 'gravitational force is balanced by outward pressure (kinetic energy + turbulent pressure)' would be better. I may try to rephrase this part later. MHD (talk) 11:11, 28 November 2007 (UTC)

Just did that part now. All I did was add a comment about other forces (besides thermal pressure) that can help to keep the cloud from collapsing: turbulence, magnetic pressure and rotation. And I added a reference. Hope that someone will check out whether it actually makes sense. MHD (talk) 12:50, 28 November 2007 (UTC)