Scientists disappointed that Fermi couldn't detect Dark Matter

The Fermi gamma-ray space telescope, aka GLAST, seems to not be able to
detect sources of gamma rays that previous telescopes seemed to detect,
that they were hoping was the long sought after signature of Dark
Matter. Oh well, keep looking for those dark things in dark places,
guys. :-

Fermi Loses Track of Possible Dark Matter - It hasn't replicated last
year's results - Softpedia
"“Particle physicists have not had much to get excited about in the last
10 years – they were all ready for the Large Hadron Collider and then
had a big setback. Then PAMELA and ATIC came along with extra
high-energy signals that could not be easily explained, and it was fun
to think about,” Douglas Finkbeiner, who is an expert on the subject
from the Harvard-Smithsonian Center for Astrophysics, said of the
progress on finding dark matter. "
http://news.softpedia.com/news/Fermi...r-110975.shtml

Yousuf Khan

On May 7, 2:43*pm, Yousuf Khan wrote:
The Fermi gamma-ray space telescope, aka GLAST, seems to not be able to
detect sources of gamma rays that previous telescopes seemed to detect,
that they were hoping was the long sought after signature of Dark
Matter. Oh well, keep looking for those dark things in dark places,
guys. :-

It is not as clear cut as Softpedia (what the ****? Softpedia?) makes
it out to be.

http://blogs.discovermagazine.com/co...n-dark-matter/

It might be nothing, but it might not be. File this under "needs moar
telescope time"


Fermi Loses Track of Possible Dark Matter - It hasn't replicated last
year's results - Softpedia
"“Particle physicists have not had much to get excited about in the last
10 years – they were all ready for the Large Hadron Collider and then
had a big setback. Then PAMELA and ATIC came along with extra
high-energy signals that could not be easily explained, and it was fun
to think about,” Douglas Finkbeiner, who is an expert on the subject
from the Harvard-Smithsonian Center for Astrophysics, said of the
progress on finding dark matter. "http://news.softpedia.com/news/Fermi-Loses-Track-of-Possible-Dark-Mat...

* *Yousuf Khan

Dear Yousuf Khan:

"Yousuf Khan" wrote in message
...
The Fermi gamma-ray space telescope, aka GLAST, seems
to not be able to detect sources of gamma rays that previous
telescopes seemed to detect, that they were hoping was the
long sought after signature of Dark Matter. Oh well, keep
looking for those dark things in dark places, guys. :-

What I don't understand is, the *only* "stuff" that can agree
with observation has *no* interactions that will produce light.
Ever. It can't be WIMPs. The bullet cluster would look much
different than it does if Dark Matter interacted with *anything*.

But hey, they got funding... and amazing things are discovered
when looking for something else entirely.

David A. Smith

On May 7, 7:52*pm, "N:dlzc D:aol T:com \(dlzc\)"
wrote:


What I don't understand is, the *only* "stuff" that can agree
with observation has *no* interactions that will produce light.
Ever. *It can't be WIMPs. *The bullet cluster would look much
different than it does if Dark Matter interacted with *anything*.

But hey, they got funding... and amazing things are discovered
when looking for something else entirely.

David A. Smith


The most sensible explanation for the galactic dark matter,
microlensing MACHOs, Bullet Cluster results, cosmic ray sources, etc.,
is huge numbers "primordial" stellar-mass [ ~ 0.2 to 0.6 solar masses]
black holes, as predicted by Discrete Scale Relativity. See
Astrophysical Journal, 322, 34-36, 1987 or
http://independent.academia.edu/Robe...ale-Relativity
..

Billions of pulsars, other types of neutron stars, and observed black
holes are the high-mass tail of this predicted galactic dark matter
population, and they tend to be in high states of rotational
excitation.

Unfortunately, this is not an answer that the physics community
covets. However, failure to find particle dark matter with the LHC,
coupled with growing evidence from Fermi Gamma-ray results, X-ray
background results, the amazing ARCADE radio emission excess and
further microlensing observations may eventually force the physics
community to recognize that it has been backing the wrong candidate or
decades.

Robert L. Oldershaw

Dear Robert L. Oldershaw:

"Robert L. Oldershaw" wrote in message
...
On May 7, 7:52 pm, "N:dlzc D:aol T:com \(dlzc\)"
wrote:

What I don't understand is, the *only* "stuff" that
can agree with observation has *no* interactions
that will produce light. Ever. It can't be WIMPs.
The bullet cluster would look much different than
it does if Dark Matter interacted with *anything*.

But hey, they got funding... and amazing things
are discovered when looking for something else
entirely.

The most sensible explanation for the galactic
dark matter, microlensing MACHOs, Bullet
Cluster results, cosmic ray sources, etc., is
huge numbers "primordial" stellar-mass [ ~ 0.2 to
0.6 solar masses] black holes,

Doesn't work for the Bullet Cluster. With that much gas around
there'd be an inordinate number of BHs with accretion disks,
especially since the intervening space has been swept clear.

....
Unfortunately, this is not an answer that the physics
community covets. However, failure to find particle
dark matter with the LHC, coupled with growing
evidence from Fermi Gamma-ray results, X-ray
background results, the amazing ARCADE radio
emission excess and further microlensing
observations may eventually force the physics
community to recognize that it has been backing the
wrong candidate or decades.

Actually, no. Those observations force them to accept that Dark
Matter is not normal matter, does not interact with normal
matter, and is diffusely distributed. This obviates any sort of
black hole as more than a tiny fraction of Dark Matter.

David A. Smith

On May 7, 6:43*pm, Yousuf Khan wrote:
The Fermi gamma-ray space telescope, aka GLAST, seems to not be able to
detect sources of gamma rays that previous telescopes seemed to detect,
that they were hoping was the long sought after signature of Dark
Matter. Oh well, keep looking for those dark things in dark places,
guys. :-

Fermi Loses Track of Possible Dark Matter - It hasn't replicated last
year's results - Softpedia
"“Particle physicists have not had much to get excited about in the last
10 years – they were all ready for the Large Hadron Collider and then
had a big setback. Then PAMELA and ATIC came along with extra
high-energy signals that could not be easily explained, and it was fun
to think about,” Douglas Finkbeiner, who is an expert on the subject
from the Harvard-Smithsonian Center for Astrophysics, said of the
progress on finding dark matter. "http://news.softpedia.com/news/Fermi-Loses-Track-of-Possible-Dark-Mat...

It's a silly headline. Fermi didn't lose track of anything, but
rather published measurements that contradict some previous
measurements. The measurements are difficult, and are subject to
difficult-to-quantify systematic errors. Some *other* previous
measurements are in agreement with Fermi's. Which measurements are
correct will be a matter of lively scientific debate, but the
principle of Ockham's Razor suggests that the less exotic Fermi
results are more likely to be correct.

CM

On May 8, 11:23*am, Craig Markwardt wrote:

It's a silly headline. *Fermi didn't lose track of anything, but
rather published measurements that contradict some previous
measurements. *The measurements are difficult, and are subject to
difficult-to-quantify systematic errors. *Some *other* previous
measurements are in agreement with Fermi's. *Which measurements are
correct will be a matter of lively scientific debate, but the
principle of Ockham's Razor suggests that the less exotic Fermi
results are more likely to be correct.

CM
----------------------------------------------------------------------------------------------------------------------

One thing regarding the Dark Matter problem is probably a safe bet.
Given that this enigma has resisted concerted efforts to solve it for
several decades, the answer is likely to require us to relinquish one
or more assumptions that we currently regard as virtually sacrosanct.

A person who has an unbiased and comprehensive understanding of the
physics and astrophysics involved knows that "primordial" black holes
are a strong candidate for the galactic dark matter. The problem is
that they do not fit the Standard Models. However, if the dark matter
should turn out to be stellar-mass ultracompact objects, then the
Standard Models of cosmology and particle physics would require major
revision.

Robert L. Oldershaw
www.amherst.edu/~rloldershaw
http://independent.academia.edu/RobertLOldershaw

Dear Robert L. Oldershaw:

On May 8, 10:06*am, "Robert L. Oldershaw"
wrote:
....
A person who has an unbiased and comprehensive
understanding of the physics and astrophysics
involved knows that "primordial" black holes are a
strong candidate for the galactic dark matter. The
problem is that they do not fit the Standard Models.

No, the problem is, Dark Matter is supposed to be located where we are
too. It should be moving in and through us *now*.

David A. Smith

On May 7, 7:26*pm, Eric Gisse wrote:
It is not as clear cut as Softpedia (what the ****? Softpedia?) makes
it out to be.

http://blogs.discovermagazine.com/co...5/04/fermi-waf...

It might be nothing, but it might not be. File this under "needs moar
telescope time"

Isn't Fermi supposed to be the new super-duper telescope for that
light range? So shouldn't we believe the results coming out of that
instrument rather than older, less expensive telescope that thought it
saw something?

Yousuf Khan

On May 8, 3:12*pm, dlzc wrote:

A person who has an unbiased and comprehensive
understanding of the physics and astrophysics
involved knows that "primordial" black holes are a
strong candidate for the galactic dark matter. The
problem is that they do not fit the Standard Models.

No, the problem is, Dark Matter is supposed to be located where we are
too. *It should be moving in and through us *now*.

David A. Smith


What observational evidence requires or even suggests that "[dark
matter] should be moving in and through us "now"."?

RLO