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0712.3934[abs pdf]
Title: A critical analysis of the GP-B mission. I: on the impossibility of a reliable measurement of the gravitomagnetic precession of the GP-B gyroscopes
Authors: G. Forst

In this paper we discuss the impossibility for the Gravity Probe B (GP-B) experiment to provide a clean and undisputable test of the gravitomagnetic precession of its four gyroscopes and of the Lense-Thirring effect. Lense-Thirring effect and geodetic precession have already been measured by Lunar Laser Ranging (LLR), laser ranged satellites, binary pulsars and accretion disks of black holes and neutron stars. In this paper we show that in the GP-B experiment there are critical problems for measuring Lense-Thirring effect and geodetic precession by the GP-B data analysis. The GP-B data analysis is extremely model dependent and relies on the assumptions about the unknown quadrupole moment induced by the gyroscopes rotation, both: (I) its size and (II) its direction with respect to the quadrupole moment due to fabrication and (III) its unknown rate of change due to variations of the gyroscopes rotation rate. The huge systematic biases in the GP-B data amount to about 1000 milliarcsec/year, but the GP-B team has claimed to be able to model 90 % of this signal, thus leaving the systematic biases at the level of about 100 milliarcsec per year, that is $\sim 300 %$ of the Lense-Thirring effect effect of the GP-B gyroscopes; any further modelling will result in a rough test of Lense-Thirring effect that will be highly model dependent and extremely affected by other huge unknown systematic biases. In this paper we show that such claims are necessarily highly model dependent and then are very much affected by huge unknown systematic biases. We give an important example of these systematic biases of which there is no mention in the discussions of the GP-B team.

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Comments (5)
Kris Krogh [2007-12-31 11:18:18]
This a message I've sent to the ArXiv moderator about this paper:

Dear arXiv-moderation,

This concerns the authorship of http://arxiv.org/abs/0712.3934 , "A critical analysis of the GP-B mission. I: on the impossibility of a reliable measurement of the gravitomagnetic precession of the GP-B gyroscopes." This paper may represent an anonymous attack.

The author's name is given as "Gerhard Forst," with the email address g.forst@yahoo.com . He has no prior ArXiv papers, and seems to have no peer-reviewed publications. His affiliation and address are given as:

G. Forst
FGP
Behrenstr. 1
10117 Berlin

Whatever FGP stands for, there is no mention on the web of such an organization at the given address. Was this paper endorsed? If so, can the endorser show "Gerhard Forst" is the author's real name?

There is an interesting similarity to papers by another author, who has a history of tit-for-tat disputes on ArXiv:

"On the impossibility of measuring a galvano-gravitomagnetic effect with current carrying semiconductors in a space-based experiment," http://arxiv.org/abs/gr-qc/0308053

"On the impossibility of using the longitude of the ascending node of GP-B for measuring the Lense-Thirring effect," http://arxiv.org/abs/gr-qc/0404107

"On the impossibility of using certain existing spacecraft for the measurement of the Lense-Thirring effect in the terrestrial gravitational field," http://arxiv.org/abs/gr-qc/0508012

"On the impossibility of measuring the general relativistic part of the terrestrial acceleration of gravity with superconducting gravimeters, http://arxiv.org/abs/gr-qc/0602005

"On some critical issues of the LAGEOS/LAGEOS II Lense-Thirring experiment," http://arxiv.org/abs/0710.1022

In addition to the titles, there are many other similarities. Comparing the most recent of these to the paper in question, there are these sequences:

"...no other tests performed by independent teams, without connections with Ciufolini and coworkers...have been so far reported in literature."

"...no independent team, without connections with the GP-B team, will be able to repeat the GP-B data analysis..."

In the former there are 4 sentences beginning with the word "Indeed." Such a sentence is also found in the latter. I could list further examples.

That author has himself claimed increasingly accurate measurements of the Lense-Thirring effect, which I've discussed here:

http://arxiv.org/abs/astro-ph/0701653

Both those claimed measurements and his reputation would be seriously threatened by a contrary result from Gravity Probe B. I hope the reasons are clear from my paper.

Best regards,

Kris Krogh

WHOISME [2009-07-17 07:40:09]
Basically, K. Krogh is claiming that G. Forst would be...Lorenzo Iorio! It sounds really comic and clearly motivated by simple envy by Krogh who has published just one (1) paper in peer-reviwed journals with respect to Iorio (more than 100). Indeed, Iorio has always demonstrated that if he has something critical to write about a test (specifically, the LAGEOS-LAGEOS II tests by Ciufolini) he always acts clearly and explicitly by publishing papers on peer-reviewed journals! Moreover, Iorio has never published anything about the gyro experiment of GP-B! Instead, it is more likely that G. Forst is Ignazio Ciufolini (often criticized by Iorio in numerous peer-reviewed papers) or some fellows of him, as clearly suggested by the arXiv moderators themselves. Moreover, on Wikipedia, at the voice frame-dragging, some years ago a comic editing war occurred, when Italian guy(s) systematically and repeatedly removed all the references by Iorio which were replaced soon after. There are no proofs, but the identity of such guy(s) should be clear..

Kris Krogh [2009-07-18 01:23:18]
I don't know who the author of the Forst paper was. In explaining their decision to withdraw the paper, ArXiv noted the name was "a pseudonym of a physicist based in Italy." This presentation by Ignazio Ciufolini, which I found later, might be relevant:



http://agenda.infn.it/getFile.py/access?contribId=33&resId=0&materialId=slides&confId=695



Forst's paper is cited against Gravity Probe B, although it only existed a short time on ArXiv, and its author was unknown in the field. If "Forst" was actually someone in Ciufolini's group, he did a very convincing impersonation of another Italian physicist, Lorenzo Iorio -- who seems to like pseudonyms too. Who else would write the preceding comment?

WuBo [2009-07-30 08:54:50]
Kris, frankly speaking, I do not really see how you can see any link of CiuForst with Iorio. Moreover, somewhere else you associated Iorio with a scientist in a totally different area who published false papers based on invented data or something like that. Without any proof! Sorry, but this is mere "gossip" at nearly defamation level. I do not understand why did you do so. Have you had something to do with Iorio in the past? Has he did something bad against you? Yours looks like personal attacks.
Concerning, Forst, well, I think that no doubts can really exist that he was Ciufolini. The style is really unique and unmistakable..Recall also the editing war about "frame-dragging" voice in Wikipedia against Iorio some years ago, when some Italian IPs sistematically removed his references..

Kris Krogh [2009-07-30 21:59:36]
WHOISME, WuBo,

Again, I don't know who Gerhard Forst was, nor who you are. Why not identify yourselves, if you are not Lorenzo Iorio?




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