Recent content by 2203312

Folks, Please don't flame me for this as it is probably already answered somewhere. How does one estimate the number of stars in a 500pc^3 which have a range of 10^-2 to 0.1 Lsun? I am not a maths head, so simple answer that would have the formula would be great. Thanks

Ok, Thanks anyway. Since I don't know what I am talking about I give up.

Ok, they are Isotopes of helium. But do they have different charges or is the charge the same as helium? and What is the charge is it -2.1x10^-21

Hi, Sorry this is a Newbie question. What is the electron charge of He-3 and He-4? I am new to physics so Sorry. Many thanks

Many thanks to each of you.

Does that mean that WIMPS are not the principal baryonic dark matter in clusters of galaxies and MACHOs in galaxy halos?

Hi, I hope someone can help me, my question is What are the principal candidates for baryonic dark matter in clusters of galaxies and in galaxy halos, are they different? I just need a list for halos and clusters as it might make it simipler for me to understand thanks in advance

Many thanks, Now the big question How did Einstein get so popular with teenage kids and that hair style?

If the Universe stopped expansion 10 million years ago and started to collapse Whould it their be such a thing as cosmological blueshift? Would the scalefactor-redshift be R=1/(z - 1) or R=1/(1+z)? I think since universe is collapsing then spectra will be blueshifted! The scale...

Many thanks for that

Hi I am just looking for the formula to calculate the baryon density of the universe at the recombination epoch. Is it a case of adding the average density of matter + radiation? but this does not take into account the recombination epoch (z=1200). I do not have a background in physics...