Vacuum Question

[foodchain]

Could stunting star formation have any impact on the expansion of the universe? Like say you cut down star formation at some certain time by say 50% of what is estimated or known would such have any noticeable impact on the expansion of the universe?

[Pangloss]

I may be out of my league here, but I'm not sure I follow your reasoning. Doesn't matter have the same gravitic pull regardless of whether or not it is condensed into a large body?

[insane_alien]

nope, wouldn't have any affect at all. pnagloss is right in that the matter will still be exherting the same pull on the larger scale.

[Klaynos]

Broadly speaking I agree with the previous two posts.

 

BUT, in stars for the most part (the main sequence of all stars) Hydrogen fuses into Helium (pretty much), the Helium has a different total mass compared to four Hydrogens (what it takes to make one He-4 nucleus). So there may actually be some difference!

[Pete]

Broadly speaking I agree with the previous two posts.

 

BUT, in stars for the most part (the main sequence of all stars) Hydrogen fuses into Helium (pretty much), the Helium has a different total mass compared to four Hydrogens (what it takes to make one He-4 nucleus). So there may actually be some difference!

The total inertial mass of such a process is conserved even when the total rest mass is not. The inertial mass shows up in terms of things like kinetic energy (a photon's energy is considered to be all kinetic energy). And its inertial mass that equals gravitational mass, not rest mass. So there will be no change in total mass when a star is formed.

 

Pete

[Arch2008]

Over 6 billion years ago, the rate of acceleration in the expansion of the universe started increasing due to the effect of Dark Energy. This “stunted” star formation because intergalactic clouds of hydrogen were no longer massing together.

So, the expanding universe had an impact on stunting star formation.

[insane_alien]

Over 6 billion years ago, the rate of acceleration in the expansion of the universe started increasing due to the effect of Dark Energy. This “stunted” star formation because intergalactic clouds of hydrogen were no longer massing together.

So, the expanding universe had an impact on stunting star formation.

 

i want to know your source on this.

[Arch2008]

About 6 billion years ago, dark energy started to accelerate the expansion of the universe.

http://chandra.harvard.edu/photo/2004/darkenergy/

At the same time, galaxy mergers slowed and star formation with them.

http://www.astronomy.com/asy/default.aspx?c=a&id=6491

Astronomers see more than a mere coincidence in this.