Main Page | Report this Page
Science Forum Index  »  Physics Forum  »  Could collisions with Dark Matter explain the...
Page 1 of 3    Goto page 1, 2, 3  Next

Could collisions with Dark Matter explain the...

Author Message
Yousuf Khan...
Posted: Tue Oct 13, 2009 11:57 pm
Guest
Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler
even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "
http://www.technologyreview.com/blog/arxiv/24232/?a=f

Yousuf Khan
 
Peter Webb...
Posted: Wed Oct 14, 2009 12:30 am
Guest
"Yousuf Khan" <bbbl67 at (no spam) spammenot.yahoo.com> wrote in message
news:4ad5684e$1 at (no spam) news.bnb-lp.com...
[quote:9ffe0cdfa7]Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

[/quote:9ffe0cdfa7]
No, its got nothing whatsoever to do with that.


[quote:9ffe0cdfa7]Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler even
calculated the kind of distribution of dark matter particles that would
explain the observed changes in velocity--a kind of halo of them around
Earth. "
http://www.technologyreview.com/blog/arxiv/24232/?a=f

Yousuf Khan
[/quote:9ffe0cdfa7]
Funny that the earth is surrounded by enough of these to noticeably slow a
spaceship, but none has even been observed on earth. I wonder if the paper
has an explanation of this curious fact ...
 
eric gisse...
Posted: Wed Oct 14, 2009 12:36 am
Guest
Yousuf Khan wrote:

[quote:dab3cf1e4e]Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
ollisions between the spacecraft and particles of dark matter. Adler
[/quote:dab3cf1e4e]
Not even wrong.

Sorry.

[quote:dab3cf1e4e]even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "
http://www.technologyreview.com/blog/arxiv/24232/?a=f

Yousuf Khan[/quote:dab3cf1e4e]
 
dlzc...
Posted: Wed Oct 14, 2009 4:33 am
Guest
Dear Yousuf Khan:

On Oct 13, 10:57 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
[quote:a60d63d4e9]Sounds like he's talking about the Aether Theory
without actually mentioning the Aether here.

Technology Review: Blogs: arXiv blog: The Clue
That Could Explain The Fly-By Anomalies
"Last year, we looked at an idea from Stephen
Adler at Princeton University,
[/quote:a60d63d4e9]
That there is a different kind of Dark Matter "in front" of a boosting
planet, than the kind "behind"... and that this Dark Matter isn't Dark
and actually must interact in ways that are obviated by other
observations. Including downing satellites anomalously.

[quote:a60d63d4e9]that suggested the change in velocity could
caused by collisions between the spacecraft
and particles of dark matter. Adler even
calculated the kind of distribution of dark
matter particles that would explain the
observed changes in velocity--a kind of halo
of them around Earth.
"http://www.technologyreview.com/blog/arxiv/24232/?a=f[/quote:a60d63d4e9]

Don't waste another thought on this Rube Goldberg contraption.

David A. Smith
 
...
Posted: Wed Oct 14, 2009 5:24 am
Guest
In sci.astro Yousuf Khan <bbbl67 at (no spam) spammenot.yahoo.com> wrote:
[quote:f5fcce4a84]Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler
even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "
[/quote:f5fcce4a84]
No. Adler's papers investigate the possibility that the flyby anomalies
might be caused by drag as spacecraft pass through a cloud of dark
matter gravitationally bound to the Earth. In his most recent preprint
he suggests a specific experimental signature (collisions with dark
matter should slightly heat the spacecraft).

The relevant preprints are arXiv:0903.4879, arXiv:0908.2414, and
arXiv:0910.1564.

Steve Carlip
 
...
Posted: Wed Oct 14, 2009 5:27 am
Guest
In sci.astro Uncle Al <UncleAl0 at (no spam) hate.spam.net> wrote:

[quote:a2812af334]By hypothesis and definition dark matter does not interact except by
gravitation.
[/quote:a2812af334]
Not true. By hypothesis, dark matter interacts weakly, but there is
certainly no requirement of no nongravitational interaction. In fact,
popular candidates (lightest supersymmetric particle, axions) certainly
do have nongravitational interactions. In fact, a major experimental
effort is going into searches for dark matter through such interactions.

Steve Carlip
 
dlzc...
Posted: Wed Oct 14, 2009 6:16 am
Guest
On Oct 14, 8:27 am, carlip-nos... at (no spam) physics.ucdavis.edu wrote:
[quote:5f589ec753]In sci.astro Uncle Al <Uncle... at (no spam) hate.spam.net> wrote:

By hypothesis and definition dark matter does not
interact except by gravitation.  

Not true.  By hypothesis, dark matter interacts weakly,
but there is certainly no requirement of no
nongravitational interaction.
[/quote:5f589ec753]
For Dark Matter as WIMPs, this is true. But the Bullet Cluster
obviates such weakly interacting Dark Matter, doesn't it? The visible
matter is pretty hot, so maybe we cannot evaluate how much normal
matter is there...

[quote:5f589ec753] In fact, popular candidates (lightest supersymmetric
particle, axions) certainly do have nongravitational
interactions.  In fact, a major experimental effort is
going into searches for dark matter through such
interactions.
[/quote:5f589ec753]
Isn't that a bit like searching for a lost item under a streetlight,
even if we did not lose the item there, because we can at least see?

David A. Smith
 
Juan R." González-Álvarez...
Posted: Wed Oct 14, 2009 8:20 am
Guest
carlip-nospam wrote on Wed, 14 Oct 2009 15:27:19 +0000:

[quote:f1c34aed1a]In sci.astro Uncle Al <UncleAl0 at (no spam) hate.spam.net> wrote:

By hypothesis and definition dark matter does not interact except by
gravitation.

Not true. By hypothesis, dark matter interacts weakly, but there is
certainly no requirement of no nongravitational interaction. In fact,
popular candidates (lightest supersymmetric particle, axions) certainly
do have nongravitational interactions. In fact, a major experimental
effort is going into searches for dark matter through such interactions.
[/quote:f1c34aed1a]
What a waste of time and money!

[quote:f1c34aed1a]Steve Carlip
[/quote:f1c34aed1a]




--
http://www.canonicalscience.org/

BLOG:
http://www.canonicalscience.org/en/publicationzone/canonicalsciencetoday/canonicalsciencetoday.html
 
Uncle Al...
Posted: Wed Oct 14, 2009 8:53 am
Guest
Yousuf Khan wrote:
[quote:bf3d8e4d11]
Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler
even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "
http://www.technologyreview.com/blog/arxiv/24232/?a=f

Yousuf Khan
[/quote:bf3d8e4d11]
By hypothesis and definition dark matter does not interact except by
gravitation. Do neutrinos slow spacecraft?

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2
 
tadchem...
Posted: Wed Oct 14, 2009 11:10 am
Guest
On Oct 14, 1:57 am, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
[quote:3706bccaa3]Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler
even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "http://www.technologyreview.com/blog/arxiv/24232/?a=f

        Yousuf Khan
[/quote:3706bccaa3]
I wonder how he determined the aerodynamic drag coefficient for dark
matter.

Tom Davidson
Richmond, VA
 
Uncle Al...
Posted: Wed Oct 14, 2009 1:55 pm
Guest
carlip-nospam at (no spam) physics.ucdavis.edu wrote:
[quote:0f73f60a00]
In sci.astro Uncle Al <UncleAl0 at (no spam) hate.spam.net> wrote:

By hypothesis and definition dark matter does not interact except by
gravitation.

Not true. By hypothesis, dark matter interacts weakly, but there is
certainly no requirement of no nongravitational interaction. In fact,
popular candidates (lightest supersymmetric particle, axions) certainly
do have nongravitational interactions. In fact, a major experimental
effort is going into searches for dark matter through such interactions.

Steve Carlip
[/quote:0f73f60a00]
CERN's axion telescope has proven to be cold manure. Collar's dark
matter detector Halon and perfluorocarbon bubble chambers are
brilliant but not implemented at scale. (If he wants to make a grant
funding splash he'll need a totally ridiculous, er, advanced working
fluid boiling around 0 C, like heptakis(trifluoromethyl)iodine. No
static molecular structure!) Ultracryogenic dark matter collision
phonon detectors are in place and working.

NO DETECTIONS. Gravity Probe B (such as it was) showed no anomaly.
Lunar laser ranging shows ZERO Nordtvedt effect.

Uncle Al calls "bullshit" on undetected matter in space in sufficient
quantities to detectably alter local orbits, by collision
cross-section or by naked gravitation. If somebody comes up with a
reproducible lab signal (not the Italian stuff), Uncle Al will
apologize.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2
 
Uncle Al...
Posted: Wed Oct 14, 2009 1:59 pm
Guest
carlip-nospam at (no spam) physics.ucdavis.edu wrote:
[quote:f8f3a94eea]
In sci.astro Yousuf Khan <bbbl67 at (no spam) spammenot.yahoo.com> wrote:
Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler
even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "

No. Adler's papers investigate the possibility that the flyby anomalies
might be caused by drag as spacecraft pass through a cloud of dark
matter gravitationally bound to the Earth. In his most recent preprint
he suggests a specific experimental signature (collisions with dark
matter should slightly heat the spacecraft).
[/quote:f8f3a94eea]
Heat the spacecraft but not ultracryogenic single phonon detectors?
Adler is curve fitting crapola against real observations.

[quote:f8f3a94eea]The relevant preprints are arXiv:0903.4879, arXiv:0908.2414, and
arXiv:0910.1564.
[/quote:f8f3a94eea]
let's not get all jiggy - the last arxiv below,

http://arxiv.org/abs/gr-qc/0205059
Pioneer anomaly
http://arXiv.org/abs/gr-qc/0307042
Rationalized Pioneer anomaly
http://arXiv.org/abs/gr-qc/9810085
Believable rationalized Pioneer anomaly
http://arXiv.org/abs/gr-qc/gr-qc/0310088
Believable Pioneer anomaly updated
http://www.arxiv.org/abs/gr-qc/0411020
Pioneer anomaly
http://arXiv.org/abs/physics/0502123
Commentary on Pioneer anomaly minutia
http://arXiv.org/abs/gr-qc/0506139
http://math.ucr.edu/home/baez/open.questions.html
http://arxiv.org/abs/0710.2656
1/3 modeled away


--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2
 
John Curtis...
Posted: Wed Oct 14, 2009 5:51 pm
Guest
On Oct 14, 6:56 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
[quote:5a208880cb]Peter Webb wrote:

"Yousuf Khan" <bbb... at (no spam) spammenot.yahoo.com> wrote in message
news:4ad5684e$1 at (no spam) news.bnb-lp.com...
Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.

No, its got nothing whatsoever to do with that.

Doesn't the Aether Theory say that things moving in space in a certain
direction shall feel a "wind" as they move? That sounds like what he's
talking about.

The "wind" here is Galactic gravity which is responsible for flyby[/quote:5a208880cb]
anomalies, especially pronounced at perihelion and aphelion, where the
planet
is aligned with the Sun and Galactic Center. At aphelion galactic
gravity
is additive and subtractive at perihelion. John Curtis
[quote:5a208880cb]
Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler
even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "
http://www.technologyreview.com/blog/arxiv/24232/?a=f

Yousuf Khan

Funny that the earth is surrounded by enough of these to noticeably slow
a spaceship, but none has even been observed on earth. I wonder if the
paper has an explanation of this curious fact ...

There's a lot that's funny about Dark Matter.

Ultimate disposition of dark matter may require abandonment of[/quote:5a208880cb]
heliocentric system in favor of a galactic frame. Copernicus and
Kepler
will join Ptolemy, Newton will require modification. John Curtis
[quote:5a208880cb]
        Yousuf Khan[/quote:5a208880cb]
 
Yousuf Khan...
Posted: Wed Oct 14, 2009 7:56 pm
Guest
Peter Webb wrote:
[quote:eb26f8ff7d]
"Yousuf Khan" <bbbl67 at (no spam) spammenot.yahoo.com> wrote in message
news:4ad5684e$1 at (no spam) news.bnb-lp.com...
Sounds like he's talking about the Aether Theory without actually
mentioning the Aether here.


No, its got nothing whatsoever to do with that.
[/quote:eb26f8ff7d]
Doesn't the Aether Theory say that things moving in space in a certain
direction shall feel a "wind" as they move? That sounds like what he's
talking about.

[quote:eb26f8ff7d]Technology Review: Blogs: arXiv blog: The Clue That Could Explain The
Fly-By Anomalies
"Last year, we looked at an idea from Stephen Adler at Princeton
University, that suggested the change in velocity could caused by
collisions between the spacecraft and particles of dark matter. Adler
even calculated the kind of distribution of dark matter particles that
would explain the observed changes in velocity--a kind of halo of them
around Earth. "
http://www.technologyreview.com/blog/arxiv/24232/?a=f

Yousuf Khan

Funny that the earth is surrounded by enough of these to noticeably slow
a spaceship, but none has even been observed on earth. I wonder if the
paper has an explanation of this curious fact ...
[/quote:eb26f8ff7d]

There's a lot that's funny about Dark Matter.

Yousuf Khan
 
N:dlzc D:aol T:com (dlzc)...
Posted: Wed Oct 14, 2009 8:47 pm
Guest
Dear Yousuf Khan:

"Yousuf Khan" <bbbl67 at (no spam) spammenot.yahoo.com> wrote in message
news:4ad68149$1 at (no spam) news.bnb-lp.com...
[quote:12cd2e5344]Peter Webb wrote:

"Yousuf Khan" <bbbl67 at (no spam) spammenot.yahoo.com> wrote in message
news:4ad5684e$1 at (no spam) news.bnb-lp.com...
Sounds like he's talking about the Aether Theory
without actually mentioning the Aether here.

No, its got nothing whatsoever to do with that.

Doesn't the Aether Theory say that things moving in
space in a certain direction shall feel a "wind" as
they move?
[/quote:12cd2e5344]
No. That aether has been discounted. So that leaves no aether,
or an aether in which matter propagates as freely as light does.

[quote:12cd2e5344]That sounds like what he's talking about.
[/quote:12cd2e5344]
It sounds like it is described that way, but it not an aether.
It is a "ponderable" magic fairy dust.

[quote:12cd2e5344]Technology Review: Blogs: arXiv blog: The Clue
That Could Explain The Fly-By Anomalies
"Last year, we looked at an idea from Stephen
Adler at Princeton University, that suggested the
change in velocity could caused by collisions
between the spacecraft and particles of dark
matter. Adler even calculated the kind of distribution
of dark matter particles that would explain the
observed changes in velocity--a kind of halo of them around
Earth. "
http://www.technologyreview.com/blog/arxiv/24232/?a=f

Funny that the earth is surrounded by enough of
these to noticeably slow a spaceship,
[/quote:12cd2e5344]
Actually, anomalously boost... both more or less of what we
intended.

[quote:12cd2e5344]but none has even been observed on earth. I
wonder if the paper has an explanation of this
curious fact ...

There's a lot that's funny about Dark Matter.
[/quote:12cd2e5344]
Yes.

David A. Smith
 
 
Page 1 of 3    Goto page 1, 2, 3  Next
All times are GMT - 5 Hours
The time now is Sat Dec 12, 2009 2:36 am