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general >> truth >> Two Anomalies
(Message started by: ThudnBlunder on Oct 19th, 2011, 7:10pm)

Title: Two Anomalies
Post by ThudnBlunder on Oct 19th, 2011, 7:10pm
Do you guys think that the Pioneer anomaly (http://en.wikipedia.org/wiki/Pioneer_anomaly) and/or the flyby anomaly (http://en.wikipedia.org/wiki/Flyby_anomaly) will eventually be explainable without recourse to a new cosmological paradigm?

Title: Re: Two Anomalies
Post by towr on Oct 19th, 2011, 10:15pm
Probably.

Title: Re: Two Anomalies
Post by ThudnBlunder on Oct 19th, 2011, 11:52pm
Or it could be comparable to the perihelion of Mercury (http://physics.ucr.edu/~wudka/Physics7/Notes_www/node98.html) phenomenon.

I posted the question after reading Chapter 2 at this (http://books.google.com/books?id=euuftB3bkUgC&printsec=frontcover&dq=13+things+that+don%27t+make+sense&hl=en&ei=M8KfTqvWC8rD8QPp9pTWBQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDMQ6AEwAA#v=onepage&q&f=false) link.


Title: Re: Two Anomalies
Post by SMQ on Oct 20th, 2011, 5:49am
As noted in the Wikipedia article, several recent studies of the Pioneer anomaly all point to radiation pressure from the onboard RTG as sufficient to explain the observations.  JPL is still updating their thermal radiation model with the new ideas, but at this point I would be comfortable calling it a "likely" explanation.

The flyby anomaly is less-well studied, and the rarity of polar-orientation gravity assists (since they result in trajectories well out of the plane of the ecliptic) makes for only a handful of data points.  All recent (last 10 years) Earth flybys have had an expected anomaly where zero falls within the prediction uncertainty, and indeed zero anomaly (within measurement uncertainty) is what has been observed. Thus we haven't really learned anything new in the past decade or so.  Makes for an interesting problem, but I suspect it will be a while before we have any progress on this one.

--SMQ

Title: Re: Two Anomalies
Post by ThudnBlunder on Oct 20th, 2011, 6:42am
Thanks for that, SMQ.  :)

Title: Re: Two Anomalies
Post by ThudnBlunder on Oct 21st, 2011, 3:01am

on 10/20/11 at 05:49:19, SMQ wrote:
...but I suspect it will be a while before we have any progress on this one.

--SMQ

How about this one?

The barman says, "Sorry, we don't serve neutrinos." A neutrino walks into a bar.   ;D

Title: Re: Two Anomalies
Post by SMQ on Oct 21st, 2011, 5:05am

on 10/21/11 at 03:01:25, ThudnBlunder wrote:
How about this one?

That one almost certainly has a mundane explanation--the scientists themselves think so as well, they just haven't found it yet--and with all the attention focused on the issue I expect it will be found within the next year.

Early analysis is mostly focusing on the minutiae of accounting for relativistic effects when performing extremely precise timing measurements using GPS signals, and indeed there's one possible calculation error which matches the reported anomaly to within the uncertainty.  However, the OPERA team claims to have performed the timing measurements accurately and noted in the original paper that all known relativistic timing effects had been accounted for--but without going into detail.  We'll have to wait for them to either update their original paper or release a new one detailing their timing corrections before we can know if that's the explanation or not.

Another possible source of error and/or confusion is the statistical methods used; they're not timing individual neutrino transit times, or even individual bunch transit times, but instead performing an aggregate analysis over thousands of bunches.  Since they can only detect a small fraction of the neutrinos sent their way it's the only way to extract the signal from the noise.  But if there's any undiscovered bias or unreported or erroneous assumptions in that highly complex statistical analysis--if, for instance, neutrinos from the head of a bunch are for some reason very slightly more likely to be detected than neutrinos from the tail--it could easily account for the observed anomaly.  Again, we'll have to wait for OPERA to publish the details and for the experts to pour over the methodology and assumptions, but that should happen in the next few months.

Meanwhile, Fermilab's neutrino experiment--the name of which escapes me at the moment--is gearing up to tighten the uncertainty in their measurements and perform their own analysis to replicate the experiment.  They already have most of the data they need, it's mostly a matter of "crunching the numbers".  They say we can expect to hear from them sometime mid 2012.

--SMQ

Title: Re: Two Anomalies
Post by ThudnBlunder on Oct 21st, 2011, 9:37am

on 10/21/11 at 05:05:16, SMQ wrote:
Meanwhile, Fermilab's neutrino experiment--the name of which escapes me at the moment...

--SMQ

MINOS (http://idealab.talkingpointsmemo.com/2011/09/was-einstein-wrong-us-accelerator-lab-to-test-cerns-results.php)

Title: Re: Two Anomalies
Post by rmsgrey on Oct 21st, 2011, 10:49am
Yeah, the FTL neutrinos are still at the stage of "that's odd, but there's probably an explanation" rather than "that's odd, but we can't explain it away".

The latter is rather more interesting for theoreticians (it means a new/modified theory is needed) but it's rare for the former to progress to the latter. What's unusual is that this time the researchers have ahd to ask for help explaining the anomaly away rather than being able to do it themselves...

Title: Re: Two Anomalies
Post by ThudnBlunder on Oct 30th, 2011, 3:33am
http://www.guardian.co.uk/science/2011/oct/28/physicists-check-neutrinos-faster-light

Title: Re: Two Anomalies
Post by khuram4u on Nov 2nd, 2011, 12:35pm

on 10/19/11 at 19:10:33, ThudnBlunder wrote:
Do you guys think that the Pioneer anomaly (http://en.wikipedia.org/wiki/Pioneer_anomaly) and/or the flyby anomaly (http://en.wikipedia.org/wiki/Flyby_anomaly) will eventually be explainable without recourse to a new cosmological paradigm?


Probably right. this exists.

Title: Re: Two Anomalies
Post by SMQ on Nov 18th, 2011, 4:43am
The OPERA team yesterday announced the preliminary results of a repeat test with very short neutrino bunches (3ns rather than 10http://www.ocf.berkeley.edu/~wwu/YaBBImages/symbols/mu.gifs) to reduce or eliminate the possibility of statistical error.  They recorded the same result: the neutrinos appeared to arrive 60ns faster than the speed of light would allow.  That ups the ante, as it means statistical error is unlikely to be able to explain the results.  Interesting!

--SMQ

Title: Re: Two Anomalies
Post by ThudnBlunder on Nov 22nd, 2011, 4:25am
http://www.guardian.co.uk/science/2011/nov/21/faster-than-light-neutrinos-doubts

Title: Re: Two Anomalies
Post by SMQ on Apr 20th, 2012, 4:18am

on 10/20/11 at 05:49:19, SMQ wrote:
JPL is still updating their thermal radiation model with the new ideas, but at this point I would be comfortable calling it a "likely" explanation.

And Here's the paper (http://arxiv.org/pdf/1204.2507v1.pdf) (pdf) with their results: "We  [...] conclude that once the thermal recoil force is properly accounted for, no anomalous acceleration remains."  So that pretty well closes the book on that one.

--SMQ

Title: Re: Two Anomalies
Post by SMQ on Jun 8th, 2012, 7:20am

on 11/22/11 at 04:25:12, ThudnBlunder wrote:
http://www.guardian.co.uk/science/2011/nov/21/faster-than-light-neutrinos-doubts

And this pretty-much puts a cap on it (http://www.symmetrymagazine.org/breaking/2012/06/08/neutrino-velocity-consistent-with-speed-of-light/): MINOS and several others (including OPERA themselves) all reported results today of neutrino speed measurements consistent with the speed of light.  Nothing to see here, folks; move along now...

--SMQ

Title: Re: Two Anomalies
Post by Grimbal on Jun 18th, 2012, 1:13pm
Yes ... or ... "they" have been successful again in hiding the truth and covering up the evidence that is bound to pop up here and there.

CIA?  Men in Black?  Aliens?  The Ministry of Magic?  I cannot tell who is pulling the strings.  But I know no secret can be kept forever.

One day we will know...

PS:  ;)

Title: Re: Two Anomalies
Post by 0.999... on Jun 18th, 2012, 8:38pm
"They" stay a step ahead of the proletariat with their superluminal communication! Darn them!

Edit - why it is so hard for me to use the Preview button I do not know.



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