Number of Galaxies Underestimated by 90%
Yousuf Khan
the ratio of galaxies is 9 times higher than observed, then that
completely removes the need for Dark Matter to explain anything.
Yousuf Khan
***
Number of Galaxies Underestimated by 90%
"According to Europe�s Very Large Telescope located in Chile, an
uncovering of previously unseen galaxies has occurred.
Some parts of the universe may have been underestimated by up to 90%.
According to the leading investigator, it means that for every 10
galaxies located, 100 were not being observed.
Interstellar clouds and space dust may have blocked light from reaching
Earth. HAWK-1, a special camera able to observe signature emissions at a
specific wavelength, unveiled clusters of previously unseen galaxies."
http://www.shortnews.com/start.cfm?id=83500
Sam Wormley
> This might have implications for Dark Matter & Dark Energy estimates. If
> the ratio of galaxies is 9 times higher than observed, then that
> completely removes the need for Dark Matter to explain anything.
>
Wrong. The distribution of matter would NOT account for the galactic
rotation speeds observed!
john
Which was exactly why DM was
trotted out in the first place.
Plus- every time the telescopes can
see farther, there will be more galaxies to see.
john
Yousuf Khan
>> This might have implications for Dark Matter & Dark Energy estimates.
>> If the ratio of galaxies is 9 times higher than observed, then that
>> completely removes the need for Dark Matter to explain anything.
>> Yousuf Khan
>
> accelerating expansion?
It wouldn't, but it would explain Dark Matter.
Yousuf Khan
Yousuf Khan
No, but the modified gravity theories would. Modified gravity, plus an
underestimation of the number of galaxies in clusters removes all need
for Dark Matter. Get it?
Yousuf Khan
dlzc
I'd like you two to add your comments to this thread:
http://groups.google.com/group/sci.physics.relativity/msg/76afeab6760f840a
As to this current thread, now I see us with having *too much* normal
matter. Big Bang cosmology only needed "67%" (some large but not
impossible amount, might be close to this) more normal matter, which
was determined to be surprising amounts of intergalactic hydrogen and
oxygen spotted between us and quasars.
David A. Smith
Sam Wormley
> On Mar 25, 8:59 am, Sam Wormley<sworml...@gmail.com> wrote:
>> On 3/25/10 8:56 AM, Yousuf Khan wrote:
>>
>>> the ratio of galaxies is 9 times higher than observed, then that
>>> completely removes the need for Dark Matter to explain anything.
>>
>> Wrong. The distribution of matter would NOT account for the galactic
>> rotation speeds observed!
>
> Which was exactly why DM was
> trotted out in the first place.
Additional baryonic matter (galaxies an hydrogen/helium gas) can
NOT account for the observed rotation rates in galaxies and clusters.
>
> Plus- every time the telescopes can
> see farther, there will be more galaxies to see.
And their gravitation obeys the inverse square law.
>
> john
dlzc
On Mar 25, 8:07 am, Yousuf Khan <bbb...@spammenot.yahoo.com> wrote:
> JohnF wrote:
> > In sci.physics Yousuf Khan <bbb...@yahoo.com> wrote:
> >> Number of Galaxies Underestimated by 90%
> >> http://www.shortnews.com/start.cfm?id=83500
> >> This might have implications for Dark Matter &
> >> Dark Energy estimates. If the ratio of galaxies
> >> is 9 times higher than observed, then that
> >> completely removes the need for Dark Matter to
> >> explain anything.
>
> > How would it (more normal baryonic matter) explain
> > accelerating expansion?
>
> It wouldn't, but it would explain Dark Matter.
No, it wouldn't explain Dark Matter. Dark Matter is found also within
galaxies. Now we have mapped DM between galaxies, perhaps some of
that is just normal matter that is not yet detectable at the energy
levels we can "see" with.
David A. Smith
dlzc
On Mar 25, 8:09 am, Yousuf Khan <bbb...@spammenot.yahoo.com> wrote:
> Sam Wormley wrote:
> > On 3/25/10 8:56 AM, Yousuf Khan wrote:
> >> This might have implications for Dark Matter &
> >> Dark Energy estimates. If the ratio of galaxies
> >> is 9 times higher than observed, then that
> >> completely removes the need for Dark Matter to
> >> explain anything.
>
> > Wrong. The distribution of matter would NOT
> > account for the galactic rotation speeds observed!
>
> No, but the modified gravity theories would.
Only f( R ) survived. TeVeS received a fatal blow.
> Modified gravity, plus an underestimation of the
> number of galaxies in clusters removes all need
> for Dark Matter. Get it?
There are still "filaments" of Dark Matter between visible galaxies...
I think you are being a little hasty yet...
David A. Smith
Yousuf Khan
Replace the galaxy rotation curves with modified gravity, and all need
for Dark Matter disappears.
Yousuf Khan
Yousuf Khan
> Dear Yousuf Khan:
>
> On Mar 25, 8:09 am, Yousuf Khan <bbb...@spammenot.yahoo.com> wrote:
>> Sam Wormley wrote:
>>> Wrong. The distribution of matter would NOT
>>> account for the galactic rotation speeds observed!
>> No, but the modified gravity theories would.
>
> Only f( R ) survived. TeVeS received a fatal blow.
Actually, neither of them would be necessary after this. You can go
right back to first principals, and resurrect the grand-daddy of
modified gravity, MOND. MOND + GR/Cosmological Constant would be
sufficient to explain the galactic scale all of the way upto the cosmic
scale.
>> Modified gravity, plus an underestimation of the
>> number of galaxies in clusters removes all need
>> for Dark Matter. Get it?
>
> There are still "filaments" of Dark Matter between visible galaxies...
> I think you are being a little hasty yet...
The filaments are most likely also explainable by unseen galaxies.
Plus that other article I just posted about the lack of runaway
supermassive blackhole expansion puts an upper limit on the density of
Dark Matter to a level that makes it impossible to be the source of
those "filaments".
Yousuf Khan
Yousuf Khan
> http://www.shortnews.com/start.cfm?id=83500
Here's a more detailed article about this discovery.
Cosmos has billions more stars than thought - Yahoo! News
"The astronomers carried out two sets of observations in the same
region, hunting for light emitted by galaxies born 10 billion years ago.
The first looked for so-called Lyman-alpha light, the classic telltale
used to compile cosmic maps, named after its US discoverer, Theodore
Lyman. Lyman-alpha is energy released by excited hydrogen atoms.
The second observation used a special camera called HAWK-1 to look for a
signature emitted at a different wavelength, also by glowing hydrogen,
which is known as the hydrogen-alpha (or H-alpha) line.
The second sweep yielded a whole bagful of light sources that had not
been spotted using the Lyman-alpha technique."
http://news.yahoo.com/s/afp/20100324/sc_afp/spaceastronomygalaxies;_ylt=Au9ZdpDTByhzALoy64r7nFaHgsgF;_ylu=X3oDMTJ0MWRlcms1BGFzc2V0A2FmcC8yMDEwMDMyNC9zcGFjZWFzdHJvbm9teWdhbGF4aWVzBHBvcwMzBHNlYwN5bl9wYWdpbmF0ZV9zdW1tYXJ5X2xpc3QEc2xrA2Nvc21vc2hhc2JpbA--
Steve Willner
Yousuf Khan <bbb...@yahoo.com> writes:
> This might have implications for Dark Matter & Dark Energy
> estimates.
Hardly!
The paper is by Hayes, Schaerer, and Ostlin (2010 A&A 509, L5; also
http://arxiv.org/abs/0912.3267). They have measured the H-alpha
luminosity function at z=2.2. H-alpha is a measure of star formation
rate (SFR), not stellar mass, and the answer the new paper gets for
SFR is squarely in the middle of existing data. (See Fig 3 of the
paper.) I am not sure where "underestimated by 90%" comes from, but
it seems to be something to do with Lyman-alpha estimates before
correction for extinction. Measuring H-alpha greatly decreases the
extinction correction, but the actual result is that the earlier
estimates were pretty much correct.
It doesn't pay to take a "headline number" too seriously unless you
know exactly what's been measured and how.
--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123 swil...@cfa.harvard.edu
Cambridge, MA 02138 USA
Yousuf Khan
> As to this current thread, now I see us with having *too much* normal
> matter. Big Bang cosmology only needed "67%" (some large but not
> impossible amount, might be close to this) more normal matter, which
> was determined to be surprising amounts of intergalactic hydrogen and
> oxygen spotted between us and quasars.
>
> David A. Smith
What exactly are you referring to by the "67%"? Big Bang needed 67% of
what?
Yousuf Khan
Yousuf Khan
> Hardly!
>
> The paper is by Hayes, Schaerer, and Ostlin (2010 A&A 509, L5; also
> http://arxiv.org/abs/0912.3267). They have measured the H-alpha
> luminosity function at z=2.2. H-alpha is a measure of star formation
> rate (SFR), not stellar mass, and the answer the new paper gets for
> SFR is squarely in the middle of existing data. (See Fig 3 of the
> paper.) I am not sure where "underestimated by 90%" comes from, but
> it seems to be something to do with Lyman-alpha estimates before
> correction for extinction. Measuring H-alpha greatly decreases the
> extinction correction, but the actual result is that the earlier
> estimates were pretty much correct.
>
> It doesn't pay to take a "headline number" too seriously unless you
> know exactly what's been measured and how.
Although H-alpha might typically be used for star-formation rates, they
used it in this case to count galaxy locations. What they found was that
there were more sources of H-alpha than there were sources of
Lyman-alpha. That means that star formation was happening in places
where we can't see a galaxy, but since star formation was happening
there, then a galaxy must exist there. So the H-alpha won't be able to
tell us the mass of that invisible galaxy, but it will mark its location.
Yousuf Khan
dlzc
On Mar 25, 12:37 pm, Yousuf Khan <bbb...@spammenot.yahoo.com> wrote:
> dlzc wrote:
> > As to this current thread, now I see us with having
> > *too much* normal matter. Big Bang cosmology
> > only needed "67%" (some large but not impossible
> > amount, might be close to this) more normal matter,
> > which was determined to be surprising amounts of
> > intergalactic hydrogen and oxygen spotted between
> > us and quasars.
>
> What exactly are you referring to by the "67%"? Big
> Bang needed 67% of what?
"Missing normal matter". Now we appear to have *way* too much normal
matter, to allow this Universe to form...
http://www.colorado.edu/news/r/81c6b13ada69601e23e0def24a37bdd6.html
David A. Smith
eric gisse
> This might have implications for Dark Matter & Dark Energy estimates. If
> the ratio of galaxies is 9 times higher than observed, then that
> completely removes the need for Dark Matter to explain anything.
Other than dynamical systems which still display dark matter.
Most this will do is tweak the global baryon density by a few points upward.
>
> Yousuf Khan
>
> ***
> Number of Galaxies Underestimated by 90%
> "According to Europe愀 Very Large Telescope located in Chile, an
> uncovering of previously unseen galaxies has occurred.
>
> Some parts of the universe may have been underestimated by up to 90%.
> According to the leading investigator, it means that for every 10
> galaxies located, 100 were not being observed.
That there's a selection bias in play is surprising to nobody. Or should be.
Sam Wormley
MOND fails where GTR succeeds!
>>>
>>> Dark Matter Exists - Sean Carroll
>>> http://blogs.discovermagazine.com/cosmicvariance/2006/08/21/dark-matter-exists/
>>>
>>> The Dark Energy Song - Sean Carroll
>>> http://blogs.discovermagazine.com/cosmicvariance/
>>>
>>> MOND is Dead? ...most likely
>>>
>>> http://www.astro.ucla.edu/~wright/density.html#MOND
>>> http://www.astro.ucla.edu/~wright/old_new_cosmo.html
>>>
>>> 22 Oct 2002 - The Chandra X-ray Observatory presented evidence
>>> against the modifications of Newtonian Dynamics (MOND) alternative
>>> to dark matter theories. The August 2002 Scientific American has a
>>> long article about MOND. The hot X-ray emitting gas around the
>>> galaxy NGC 720 forms an ellipsoidal cloud, which requires an
>>> ellipsoidal gravitational potential well. While an ellipsoidal
>>> cloud of dark matter could provide such a well, MOND would
>>> necessarily give a spherical potential well. In general MOND works
>>> well on the scale of individual galaxies, but not for clusters of
>>> galaxies. So why is MOND only maybe dead? Its supporters like
>>> Milgrom are persistent and clever, and they may come up with a
>>> MONDian explanation for NGC 720.
>>>
>>> More on Dark Matter
>>> http://www.astro.ucla.edu/~wright/cosmolog.htm#News
>>>
>>> 21 Aug 2006 - NASA announced updated information about the "bullet
>>> cluster" 1E0657-56 today. Two clusters of galaxies have recently
>>> collided in this X-ray source. This cluster is filled with hot gas
>>> so X-ray observations by the Chandra X-ray Observatory show where
>>> the ordinary matter is located. 90% of the ordinary matter (the
>>> "baryonic" matter) is hot gas.
>>>
>>> The new results [Clowe et al., Bradac et al.] use gravitational
>>> lensing of background galaxies to show where the sources of gravity
>>> are located. The sources of gravity in the cluster are not located
>>> where the ordinary matter is located, so this cluster is a
>>> counter-example to MOND. All of this was known in 2003 but with
>>> less precision. Sean Carroll has a nice post about this at Cosmic
>>> Variance.
>>>
>>> The Matter of the Bullet Cluster
>>> http://antwrp.gsfc.nasa.gov/apod/ap060824.html
>>>
>>> Explanation: The matter in galaxy cluster 1E 0657-56, fondly known
>>> as the "bullet cluster", is shown in this composite image. A mere
>>> 3.4 billion light-years away, the bullet cluster's individual
>>> galaxies are seen in the optical image data, but their total mass
>>> adds up to far less than the mass of the cluster's two clouds of
>>> hot x-ray emitting gas shown in red. Representing even more mass
>>> than the optical galaxies and x-ray gas combined, the blue hues
>>> show the distribution of dark matter in the cluster. Otherwise
>>> invisible to telescopic views, the dark matter was mapped by
>>> observations of gravitational lensing of background galaxies.
>>>
>>> In a text book example of a shock front, the bullet-shaped cloud of
>>> gas at the right was distorted during the titanic collision between
>>> two galaxy clusters that created the larger bullet cluster itself.
>>> But the dark matter present has not interacted with the cluster gas
>>> except by gravity. The clear separation of dark matter and gas
>>> clouds is considered direct evidence that dark matter exists.
>>>
>>>
>>> More: http://physicsandphysicists.blogspot.com/2008/02/more-problems-with-mond.html
>>>
>>>
Steve Willner
Yousuf Khan <bbb...@spammenot.yahoo.com> writes:
> Although H-alpha might typically be used for star-formation rates, they
> used it in this case to count galaxy locations.
I suggest you read the paper (or the preprint), not the press
release or news articles about it.
> What they found was that
> there were more sources of H-alpha than there were sources of
> Lyman-alpha. That means that star formation was happening in places
> where we can't see a galaxy,
That's no surprise. Anyone working with Lyman-alpha (i.e.,
ultraviolet) counts makes corrections for extinction. Even the
H-alpha counts have to be corrected, but the correction is much
smaller. The result (Figure 3 of the paper) is that the star
formation rate is about the same as previous estimates but now with
smaller uncertainties.
BURT
the outer stars have more speed.
Mitch Raemsch
Brad Guth
Cosmic carbonado or just plain carbon doesn't exist?
Faster stars and those fast receding galaxies; do tell what's making
them go faster and faster.
~ BG