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Study Plunges Standard Theory Of Cosmology Into Crisis



 
 
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  #1  
Old November 6th 13, 06:44 AM posted to sci.astro,sci.physics
Yousuf Khan[_2_]
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Default Study Plunges Standard Theory Of Cosmology Into Crisis

Study Plunges Standard Theory Of Cosmology Into Crisis
http://www.sciencedaily.com/releases...0505061949.htm

"May 5, 2009 — As modern cosmologists rely more and more on the ominous
“dark matter” to explain otherwise inexplicable observations, much
effort has gone into the detection of this mysterious substance in the
last two decades, yet no direct proof could be found that it actually
exists. Even if it does exist, dark matter would be unable to reconcile
all the current discrepancies between actual measurements and
predictions based on theoretical models. Hence the number of physicists
questioning the existence of dark matter has been increasing for some
time now.

Competing theories of gravitation have already been developed which are
independent of this construction. Their only problem is that they
conflict with Newton’s theory of gravitation. “Maybe Newton was indeed
wrong,” declares Professor Dr. Pavel Kroupa of Bonn University´s
Argelander-Institut für Astronomie (AIfA). “Although his theory does, in
fact, describe the everyday effects of gravity on Earth, things we can
see and measure, it is conceivable that we have completely failed to
comprehend the actual physics underlying the force of gravity.”"

***

And that's not all, there's more and more evidence that modified gravity
theories are right, as they *predict* newly observed never-before-seen
behaviour, and not just pre-existing observations, while Dark Matter
seems to always need to be fine-tuned or remodelled to fit these
observations.

Modified law of gravity predicts dwarf galaxy feature prior to observations
http://www.sciencedaily.com/releases...0828103446.htm

"Aug. 28, 2013 — A modified law of gravity correctly predicted, in
advance of the observations, the velocity dispersion -- the average
speed of stars within a galaxy relative to each other -- in 10 dwarf
satellite galaxies of the Milky Way's giant neighbor Andromeda."

***

That, above, was a recent study of the dwarf galaxies around Andromeda,
but earlier studies of dwarf galaxies around the Milky Way found the
exact same thing! So more and more confirmation.

Time For A New Theory Of Gravitation? Satellite Galaxies Challenge
Newtonian Model
http://www.sciencedaily.com/releases...0422085830.htm

"Apr. 23, 2009 — The high speed of stars and apparent presence of ‘dark
matter’ in the satellite galaxies that orbit our Milky Way Galaxy
presents a direct challenge to Newton’s theory of gravitation, according
to physicists from Germany, Austria and Australia."

***

At the scales of galaxy clusters, Dark Matter models rule, but that's
the only scale at which they do. At all lower scales, they are very weak
at their predictions.

Gas rich galaxies confirm prediction of modified gravity theory
http://www.sciencedaily.com/releases...0223092406.htm

"Feb. 25, 2011 — Recent data for gas rich galaxies precisely match
predictions of a modified theory of gravity known as MOND, according to
a new analysis by University of Maryland Astronomy Professor Stacy
McGaugh. This -- the latest of several successful MOND predictions --
raises new questions about accuracy of the reigning cosmological model
of the universe, writes McGaugh in a paper to be published in March in
Physical Review Letters."

"Of course, McGaugh said, one can start from the assumption of dark
matter and adjust its models for smaller scales until it fits the
current finding. "This is not as impressive as making a prediction ahead
of [new findings], especially since we can't see dark matter. We can
make any adjustment we need." This is rather like fitting planetary
orbits with epicycles," he said. Epicycles were erroneously used by the
ancient Greek scientist Ptolemy to explain observed planetary motions
within the context of a theory for the universe that placed Earth in its
center."

***

I think the question is with so many precise predictions being
attributed to MOND-like theories, why are there still so many scientists
still clinging on to Dark Matter as the starting point? Because it's too
hard to believe that sacrosanct Newton's Laws could be wrong, and that
it's much easier to make up undetectable particles? Earlier generations
of scientists had no trouble overturning Newton's Laws if they didn't
fit the observations, afterall that's exactly what Einstein's Laws are
about: they overturned Newton's Laws at higher scales. We're going
through a similar paradigm shift now, but today's generation of
scientists insist on not sticking their necks out and saying that
Newton's Laws could possibly be wrong. Pathetic!

They should be assuming MOND, and seeing how to go from there, not
assuming Dark Matter first.

Yousuf Khan
  #2  
Old November 6th 13, 07:24 AM posted to sci.astro,sci.physics
Jan Panteltje
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Posts: 453
Default Study Plunges Standard Theory Of Cosmology Into Crisis

On a sunny day (Wed, 06 Nov 2013 01:44:37 -0500) it happened Yousuf Khan
wrote in :

I think the question is with so many precise predictions being
attributed to MOND-like theories, why are there still so many scientists
still clinging on to Dark Matter as the starting point? Because it's too
hard to believe that sacrosanct Newton's Laws could be wrong, and that
it's much easier to make up undetectable particles? Earlier generations
of scientists had no trouble overturning Newton's Laws if they didn't
fit the observations, afterall that's exactly what Einstein's Laws are
about: they overturned Newton's Laws at higher scales. We're going
through a similar paradigm shift now, but today's generation of
scientists insist on not sticking their necks out and saying that
Newton's Laws could possibly be wrong. Pathetic!

They should be assuming MOND, and seeing how to go from there, not
assuming Dark Matter first.

Yousuf Khan


It is good the professor mentions: "underlying physics'
We need a _mechanism_ as even MOND is just a formula.

Sure, you observe some effect, and quantify it so you end up with an equation that for most
purposes, within your experimental 'zone' describes and predicts things to within some
small error.

But we really need to KNOW what gravity is, what causes it, how it is transferred, by what,
how fast, etc.

One reason people go for dark matter is the absence of grey matter,
:-)

There is no better way to get life time security than searching for something that does not exist funded
by the taxpayer's money.
At that level the grey matter is very active.
That is also why we have LIGO (graffiti waves) and CERN (God particle), ITER (f*cksion in the next 100 years, etc.
The medieval times had epicycles, and many learned -, or better only very learned
people could understand that and do the required calculations,
they had a good job doing market protection in their way.
Almost like fighting global warming... these days.

So there is some slugginess in the human race, status quo blah blah.
Wars where the ( (future) winner who takes all) WORKING science becomes important is where
we in the past have seen the advances, liquid fuel missiles, radar, submarines, etc etc.
So, unless some major shake up happens we can be searching for elves or Elvis alive or whatever for many more years.
  #3  
Old November 6th 13, 10:45 PM posted to sci.astro,sci.physics
Steve Willner
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Posts: 1,172
Default Study Plunges Standard Theory Of Cosmology Into Crisis

In article ,
Yousuf Khan writes:
I think the question is with so many precise predictions being
attributed to MOND-like theories, why are there still so many scientists
still clinging on to Dark Matter as the starting point?


Perhaps because "so many" is really "hardly any." (I'm afraid the
sources in the OP are either ill-informed or biased.)

that's exactly what Einstein's Laws are
about: they overturned Newton's Laws at higher scales.


As you say, GR is a so-far completely successful theory of gravity
after many highly precise tests. GR could be wrong -- indeed it must
be wrong at some level because it isn't quantized -- but it's not
reasonable to throw it out without very strong evidence. That
doesn't stop people from thinking how it could be wrong and devising
new tests.

They should be assuming MOND, and seeing how to go from there, not
assuming Dark Matter first.


That's a minority and shrinking view, but we'll see what the evidence
says as it comes in.

Some people have a strange idea of how science works. What you or I
find logically appealing is irrelevant; all that matters is what the
evidence shows.

--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
  #4  
Old November 8th 13, 03:11 PM posted to sci.astro,sci.physics
Yousuf Khan[_2_]
external usenet poster
 
Posts: 1,692
Default Study Plunges Standard Theory Of Cosmology Into Crisis

On 06/11/2013 2:24 AM, Jan Panteltje wrote:
It is good the professor mentions: "underlying physics'
We need a _mechanism_ as even MOND is just a formula.

Sure, you observe some effect, and quantify it so you end up with an equation that for most
purposes, within your experimental 'zone' describes and predicts things to within some
small error.

But we really need to KNOW what gravity is, what causes it, how it is transferred, by what,
how fast, etc.


Lee Smolin's book, The Trouble with Physics, mentioned a tantalizing
relationship between MOND's critical acceleration constant, and the
radius of Dark Energy's effect. Specifically it suggests that Dark
Energy's effective radius is 10 billion LY's, which corresponds to an
inverse relationship between MOND's critical acceleration and the speed
of light! That could be a total coincidence, but it's a spectacular
coincidence. Again, it's just a bunch of formulas, and finding a pattern
in those formulas, with no underlying understanding of why it may work.
The underlying understanding has yet to come.


Yousuf Khan
 




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