Recent content by electerr

I thought the neutron's decay time is more like 15 minutes. http://en.wikipedia.org/wiki/Neutron#Stability_and_beta_decay Maybe your hinting that the decay time is slower at such high temps as there was during BBN...? At the end of BBN, without neutron decay, I think it is calculated...

Ok, so it is actually a picture of the past with the only difference being the wavelength. Great, now I know... Thanks for the help!

Thanks for your reply Jorrie! Can anyone confirm this? I thought that the universe was smoother in the past, wouldn't these changes in the density affect the way the CMB looks? Thanks again!

Hi, Am I right when I say that the cosmic microwave background is a picture of the radiation left from recombination but that the picture (from COBE or WMAP) that we see today is not exactly the same as it was then due to the redshifting of the radiation particles. The flucuations that we see...

Ok, I didn't know about the separate Friedmann acceleration equation. Thanks for the help!

Hi, I am trying to understand how it is possible to make predictions about the energy density of early universe using the freidman equation if the expansion rate of the universe has not been constant throughout history. As I understand it there are three main variables in the freidman...

As I understand it, it can be calculated that 1 minute after the big bang, when protons and neutrons freeze out and are no longer being created, that for every neutron that exists there are 7 protons. Does anyone know what equation is used to calculate this and if it is not a equation that is...

Ok, that makes sense. Good analogy by the way, makes it much eaiser to picture the expansion in my mind. Thanks a lot!

Hello, I am trying to understand that in order for the universe to be expanding that galaxies at further distances must be moving away from us at faster speeds than galaxies closer to us. It seems enough that all galaxies are moving away from us (or each other if observed from another galaxy)...

Perfect! That helped a lot! Thanks!

Ok great, that clears things up then. One more thing, is there a equation that describes the relationship between an objects "surface gravity" and it's mass? Thanks again for the help!

Hi, I am a bit confused with how a neutron star or black hole has such a high force of gravity. As I understand the process of star death of a massive star (I'll use a neutron star for example), 1) the star fuses heavier and heavier elements 2) the core begins to contract 3) this...

Thanks for the help, after your comments and some quality time on Wikipedia I think I got everything worked out now... I think that it made it difficult for me that, when I first heard about fermions and bosons they were presented as 'matter particles' and 'force particles' and I was focusing...

And one more thing... If this is the 'standard definition'... Does this mean that not all fermions are 'matter particles' and not all bosons are 'force particles' and that bosons can make up matter and fermions can make up forces...?

The first part of the explanation was spot on, thanks but... Can you explain what you mean by this... Which classification are you referring to? And fundamental and composite, haven't heard of those... are they diffrent types of bosons?