Jump to content

coexisting hypotheses


Blade
 Share

Recommended Posts

they are not mutually exclusive.

 

Supermassive blackholes at the center of galaxies is fact not hypothesis. IIRC we have yet to find a galaxy without one.

 

Missing mass is also fact as this is observed. Dark matter is just used as a placeholder for whatever it is that makes up the extra mass. it may even turn out to not be matter.

Link to comment
Share on other sites

I thought super massive black holes were quite a recent discovery - like in the 90's or something. First I ever heard of them was on a Horizon program sometime arround 2000 - 2003.

 

How do we find out exactly when they were discovered?

Link to comment
Share on other sites

The Wilkinson Microwave Anisotropy Probe (WMAP) shed some light on dark matter. Apparently it was here right from the beginning of the universe. Some candidates for DM are MACHOS (MAssive Compact HalO objectS) and WIMPS (Weakly Interactive Massive ParticleS). MACHOS are described as brown dwarf stars or minor black holes in the halo of a galaxy, whereas WIMPS are simply nuclear particles that interact weakly with the electromagnetic force, so they can essentially float right through your molecules and do not reflect light, etc. Since there were no stars at the beginning of the universe, I think that WIMPS are the most likely candidate.

The DM was unaffected by the energy of the early universe. Enormous clouds of DM started collapsing while the ordinary matter was still too energized to form atoms. At about 380,000 years after the Big Bang, the universe cooled and atoms of hydrogen, helium and a dash of lithium formed. The gravity of the DM clouds caused these atoms to collapse and form the first stars and galaxies. Thus the supermassive black holes formed because of the DM.

http://map.gsfc.nasa.gov/news/

Link to comment
Share on other sites

I thought super massive black holes were quite a recent discovery - like in the 90's or something. First I ever heard of them was on a Horizon program sometime arround 2000 - 2003.

 

How do we find out exactly when they were discovered?

 

We go to wikipedia... :P

 

And we say about 1993...

 

Dark energy: 1975 ish...

 

So dark energy was much earlier... interesting...

 

Most of the dark matter is outside the centre of the galaxy.

Link to comment
Share on other sites

It looks as though the conection between SMBH's and galaxy formation was put forward in June 2000. This is what the Horison program was going on about. Not sure about the actual SMBS discovery though.

 

 

WIMPS and MACHOS -- Always thought that was funny!... :D

 

 

Most of the dark matter is outside the centre of the galaxy.

 

Then the discovery of SMBHs would make no difference to the theories on dark matter then, as the SMBHs are at the centre of galaxies right?

Edited by DrP
Link to comment
Share on other sites

Then the discovery of SMBHs would make no difference to the theories on dark matter then, as the SMBHs are at the centre of galaxies right?

 

Yes, it might make some difference I suppose as some of the dark matter is near the centre, but not much/enough :s

Link to comment
Share on other sites

My online access only goes to 2001...

 

But the joys of google scholar ;)

 

15 citations...

 

http://scholar.google.co.uk/scholar?hl=en&lr=&client=firefox-a&cites=3551569314637459921

 

http://www.iop.org/EJ/abstract/0034-4885/60/2/001

 

looks like it might be a good place to look... Which I do have access too ;)

 

Well after trying to grab it as I'm currently between courses my library account is in a semi-locked stage... so I can log in but can't actually do anything useful!

Link to comment
Share on other sites

The WMAP data indicate the existence of Dark Matter right from the beginning of the universe. This pretty much pulls the rug out from under VG or MOND. Neutrinos were also found to have a miniscule mass.

 

what/where dous MOND stand for?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.