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Stat
Members: 1977
Articles: 1'805'111
Articles rated: 2556

14 December 2017
 
  » recent reviews

  Recent Reviews


37 recent reviews found:
(To access fulltext of a review, click on titles below.)
1. Science-advisor.net review 16090070    * Rate this comment.
Article reference: Structure of the catalytic domain of human phosphodiesterase 5 with bound drug molecules.
Review title: The head of the World Best Cure
Reviewer: reviewer1919
Date: 09 September 2016 at 20:16 GMT.
Comment: I aim and engage on essential regulators of cyclic nucleotide signalling with diverse physiological functions, PDEs are drug targets for the treatment of various diseases, including heart failure, depression, asthma, inflammation and erectile dysfunction better research on www.comprarviagras.com

2. Science-advisor.net review 15080069    * Rate this comment.
Article reference: RF-Based Charger Placement for Duty Cycle Guarantee in Battery-Free Sensor Networks.
Review title: Battery free RFID = less trouble in human bodies
Reviewer: reviewer1877
Date: 21 August 2015 at 11:25 GMT.
Comment: Medical applications of sensor networks inside the body would seem to benefit from not needing to get into surgery to replace batteries.

3. Science-advisor.net review 15060068    * Rate this comment.
Article reference: Errors in Mathematical Proofs.
Review title: good article
Reviewer: reviewer1866
Date: 04 June 2015 at 16:31 GMT.
Comment: i am doing my thesis about error analysis of identity trigonometry and i was search for the theory about how to prove mathematics and unfortunately i didn't find it, but at this day i find out about this article by Raphael Zahler and i hope his journal can help me to finished my thesis.

4. Science-advisor.net review 14110067    * Rate this comment.
Article reference: Microscopic boson description of proton-neutron systems: Application to elastic and inelastic electron scattering from 18O and 20Ne.
Review title: Read
Reviewer: reviewer1825
Date: 07 November 2014 at 23:30 GMT.
Comment: I would like to read it because I work on the same nuclei.

5. Science-advisor.net review 13100066    * Rate this comment.
Article reference: Early cultivators of science in Japan.
Review title: Case Study
Reviewer: reviewer1806
Date: 02 October 2013 at 11:32 GMT.
Comment: It's a good paper as you can learned some very important history of science development in early Japan and some important scientists in the past.

However, there are two great scientist that i must mentioned - Mr. Sugita Genpaku and Mr. Kagawa Gen'etsu. Both of them show what kind of good spirit a scientist should have as they not only contribute to science, but also to the people.

In SCIENCE VOL. 258, published on 23 Octorber 1992, page 580, second line of the first paragraph, , Emperor Akihito wrote that "What Genpaku and Gen'etsu shared in common was A LOVE FOR PEOPLE".

Yes, LOVE FOR PEOPLE! These 3 words stunned me when i read them. There is a moment i cant think of others but LOVE FOR PEOPLE. Politician may misuse it, businessman may misuse it. But scientist, should always study, develop, and use science for people, in a way of loving them.

6. Science-advisor.net review 13070065    * Rate this comment.
Article reference: Nonlinear dynamics of dual-frequency-pumped multiwave mixing in optical fibers.
Review title: a good article
Reviewer: reviewer1790
Date: 26 July 2013 at 18:15 GMT.
Comment: it seems to be helpful for me in order to give insight in the field of ultrashort optical pulse generation 

7. Science-advisor.net review 12090064    * Rate this comment.
Article reference: Domain wall solitons in binary mixtures of Bose-Einstein condensates.
Review title: good
Reviewer: reviewer1700
Date: 12 September 2012 at 12:46 GMT.
Comment: good good good good  good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good goodgood good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good

8. Science-advisor.net review 12070063    * Rate this comment.
Article reference: Genetic instability and outcrossing in the groundnut variety Mani Pintar.
Review title: nice article
Reviewer: reviewer1692
Date: 12 July 2012 at 23:37 GMT.
Comment: though this article looks very old. it gives the background information on early works on variability and outcrossing on testa colour inheritance and groundnut

9. Science-advisor.net review 12040062    * Rate this comment.
Article reference: Biomonitoring. Pollution gets personal.
Review title: Its very informative
Reviewer: reviewer828
Date: 25 April 2012 at 17:55 GMT.
Comment: Its very good article. I work on biomonitoring & biomapping hence i found it very interesting. If one care about environment, its one of chipest method.

10. Science-advisor.net review 11040061    * Rate this comment.
Article reference: Astronomical alignments as the cause of ~M6+ seismicity.
Review title: Amazing
Reviewer: reviewer1604
Date: 15 April 2011 at 14:09 GMT.
Comment: This is important discovery. Text and data are amazing. We now know why earthquake happen.

11. Science-advisor.net review 10070060    * Rate this comment.
Article reference: Intra-unit-cell electronic nematicity of the high-Tc copper-oxide pseudogap states.
Review title: Electronic nematicity in high-Tc pseudogap phase
Reviewer: reviewer8
Date: 20 July 2010 at 07:55 GMT.
Comment: This work find evidence for electronic nematicity close to the pseudogap energy. It is however not clear whether the pseudogap state is directly related to the nematicit.

12. Science-advisor.net review 10040059 (1 reader)    * Rate this comment.
Article reference: The P versus NP Brief.
Review title: Unconventional with novel approaches!
Reviewer: reviewer1536
Date: 28 April 2010 at 18:15 GMT.
Comment: The author uses unconventional methods and notation in order to show that P is most likely not equal to NP. At first I was a bit appalled at his methods, but then, having read it again, I actually came to agree with it. Despite the paper's length of only 4 pages the author manages to present some very neat cases. The main argument may seem oversimplified but it's kept afloat by elegant mathematics.

13. Science-advisor.net review 09100058 (1 reader)    * Rate this comment.
Article reference: Phase operators on Hilbert space.
Review title: verygood
Reviewer: reviewer
Date: 30 October 2009 at 09:29 GMT.
Comment: quantum information, phase operators, infinite rank, so it is a paper I need to read.

14. Science-advisor.net review 09100057 (1 reader)    * Rate this comment.
Article reference: Unitary transformation for four harmonically coupled identical oscillators.
Review title: very good
Reviewer: reviewer
Date: 16 October 2009 at 09:02 GMT.
Comment: The paper is very good. I need it. I am a reasercher of theoritical physics.

15. Science-advisor.net review 09060056    * Rate this comment.
Article reference: Cosmology: digitizing the universe.
Review title: good
Reviewer: reviewer1388
Date: 22 June 2009 at 02:53 GMT.
Comment:

thx for this good article

Quran , our holy book   notes this matter


16. Science-advisor.net review 09020055    * Rate this comment.
Article reference: Read before you cite!.
Review title: How to use misprints!
Reviewer: reviewer8
Date: 24 February 2009 at 16:36 GMT.
Comment: This article shows what everyone knows: cited articles are seldom read. The authors shows that 80% of cited articles are not read by the citing authors. This may be an upper bound.

17. Science-advisor.net review 09020054    * Rate this comment.
Article reference: High-order harmonic radiation from solid layers irradiated by subpicosecond laser pulses.
Review title: important
Reviewer: reviewer1311
Date: 03 February 2009 at 11:33 GMT.
Comment: resd this article. please send any readable in this subject.

18. Science-advisor.net review 08060053    * Rate this comment.
Article reference: Finding Scientific Gems with Google.
Review title: A different point of view on bibliometrics
Reviewer: reviewer8
Date: 10 June 2008 at 11:45 GMT.
Comment: This article proposes to use the Google PageRank to find important and precursor scientific articles. This approach allows to compare directly articles from different fields. Unlike traditional bibliometric methods, the PageRank approach does not need a rescaling by scientific fields.

19. Science-advisor.net review 08060052    * Rate this comment.
Article reference: An index to quantify an individual’s scientific research output.
Review title: A simple formula to quantify research output
Reviewer: reviewer8
Date: 10 June 2008 at 11:41 GMT.
Comment:

This article introduce a new mathematical index that allows to quantify the research output of a researcher. This mathematical formula is nice and simple. The h-index should be however seen as a guidline or a toy model more than a serious evaluation tool.


20. Science-advisor.net review 08030051    * Rate this comment.
Article reference: Quantum Phase Transitions and Bipartite Entanglement.
Review title: great paper
Reviewer: reviewer1161
Date: 04 March 2008 at 18:06 GMT.
Comment: this is a great paper that develop a general theory of the relation between quantum phase transitions (QPTs) characterized by nonanalyticities in the energy and bipartite entanglement. We derive a functional relation between the matrix elements of two-particle reduced density matrices and the eigenvalues of general two-body Hamiltonians of $d$-level systems. The ground state energy eigenvalue and its derivatives, whose non-analyticity characterizes a QPT, are directly tied to bipartite entanglement measures. We show that first-order QPTs are signalled by density matrix elements themselves and second-order QPTs by the first derivative of density matrix elements. Our general conclusions are illustrated via several quantum spin models.

21. Science-advisor.net review 07100050    * Rate this comment.
Article reference: Fundamental length scale of quantum spacetime foam.
Review title: Important Factual Errors
Reviewer: reviewer927
Date: 13 October 2007 at 16:23 GMT.
Comment: The last time I measured spacetime foam, it was roughly 2.86mm long. Admittedly, it was using an old ruler and the spacetime foam was slightly bent.

22. Science-advisor.net review 07100049    * Rate this comment.
Article reference: Superconductivity due to co-operative Kondo effect in Pu 115’s.
Review title: Important Factual Errors
Reviewer: reviewer927
Date: 13 October 2007 at 16:14 GMT.
Comment:

Strong correlated electrons?  The correlations are medium to weak, at BEST.

 I think a simple explanation for these so called anomalous properties of the PuCoGa$_5$ and PuRhGa$_5$ compounds is readily avaliable...  TO ANYONE WITH A BRANE!  You should be aware gravitational forces are HUGE between brane point particles.  I can tell you need to increase you are brain mass.

Why would you use the sympletic large-N approach, you said yourself there is a large N limit!  Honestly, how can you expect to write about SUPERconductivity when you clearly do not understand normal conductivity.

If you want help I can explain this to you, give me a ring 520.405.5258 

 

P.S. Where you wrote "The symmetry of the order parameter" I believe you meant to say "The antisymmetry of the same parameter" This will bring out the conduction channels to a higher "Degree" so to speak.  Welcome :D


23. Science-advisor.net review 07100048 (1 reader)    * Rate this comment.
Article reference: Gravitational Forces in the Brane World.
Review title: Important Factual Errors
Reviewer: reviewer927
Date: 13 October 2007 at 16:02 GMT.
Comment:

Why would you assume that matter produces pterbation to the R-S vacuum metric?  Remember assumptions make an ASS out of U and ME.

 

I also have a problem with your idea of gravitational forces between point particles on the brains in a Randall-Sundrum two brain model.  I think in this type of medium you need to use proper and precise terminology and spelling, we are all scientists here so lets call a spade a spade and point particles on the brain "axons".  "Brain bending"? more like "Crazy"!

 

Also I think we can be relatively sure that any gravitation between brain particles will be small.  Real small.  Have you ever heard of "G = (M1 * M2)/d^2?  It is called highschool open a book you retard.

 

 

P.S. 

I believe you mean "$S^1/Y_2$ symmetry"


24. Science-advisor.net review 07080047 (1 reader)    * Rate this comment.
Article reference: Superconductivity due to co-operative Kondo effect in Pu 115’s.
Review title: The approach should be working for other superconductors
Reviewer: reviewer
Date: 21 August 2007 at 21:13 GMT.
Comment:

This mechanism is working for cuprates as well. Even for a single conduction band if formally Gamma= Cu 4s and f= Cu 3d_{x^2-y^2}, the model describes d-type superconductivity of CuO_2 plane.


25. Science-advisor.net review 07040046    * Rate this comment.
Article reference: New northern common proper motion pairs.
Review title: Flawed analysis of incorrect data
Reviewer: reviewer637
Date: 04 April 2007 at 08:46 GMT.
Comment:

The basic idea behind the article, that is using common proper data to identify possible binary stars, is sound.

Unfortunately the methods used to identify potential candidates are fatally flawed relying as they do on the ratios of the proper motions of the two components rather than on the difference between the two values.

It is believed that the author now accepts that at least 1/3rd of the pairs listed are totally spurious. 

 


26. Science-advisor.net review 06080043 (5 readers)    * Rate this comment.
Article reference: Springtide-induced magnification of Earth mantle resonance causes tectonics and conceals universality of physics at all scales.
Review title: A landmark paper solves tectonics puzzle and computes Newtonian constant of gravitation
Reviewer: reviewer333
Date: 27 August 2006 at 02:52 GMT.
Comment: This must be one of the most incredible papers I read in decades. The author (who is a geophysicist) first shows that the earth shakes due to spring-tidal resonance of its mantle! This is all pretty basic calculus and I don’t see how anyone in or outside the field of geophysics will be able to dispute its correctness. Even if it’s one of the most unusual papers they will read. Observations that were made using superconducting gravimeter support the model. The model was demonstrated as standing in excellent agreement with straightforward formulas of forced oscillator. (Dr. Omerbaschich also claims that his resonance is responsible for G-experiments' inconsistencies, the earth magnetic field and some other phenomena.) As if that alone was not a huge claim to make, the author takes it even further. In order to prove that natural forced oscillators such as earth-moon are real, he posits that the universe consists of (almost) infinitely many such forced oscillators! It ends with a theory according to which the vacuum energy (the author calls it dark matter/energy, but I think that was an unnecessary mystification) vibrates while carrying – gravitation! There is another twist: gravity is not attractive but REPULSIVE i.e. it propagates FORWARD. What's more: it does it MECHANICALLY i.e. so that each particle's orbit interacts with to it adjacent particle orbit(s) by locking into a single forced oscillator, and so on. If this were "just another wacky theory", believe me – I would have not bothered. But it contains many remarkable expressions, and as far as I could tell they are all correct! The most remarkable however seems Dr. Omerbashich’s closing argument: G (and not physics!) changes with scale, so that both quantum mechanics and relativity theory were conceived on cardinally flawed premises (given that the Planck’s constant is determined via instrumentation that gets affected by the springtide in the same manner in which gravimeters are shown). To show that he is not all about talking, Dr. Omerbaschich demonstrates with total serenity that his model predicts (correctly mind you, I did run the numbers) the currently accepted experimental values of the Newtonian constant on both mechanical and Planck scales. (The formula also predicts G on the string-size as well as universe-size scales, too.) Just one simple formula does it all – a formula which, according to my book, represents the first theoretical prediction of experimental value of a physical constant in history. There is no doubt in my mind that G=se2 is to make history, on a par with E=mc2.

27. Science-advisor.net review 06070042 (3 readers)    * Rate this comment.
Article reference: Anomalous precursor diamagnetism at low reduced magnetic fields in underdoped La1.9Sr0.1CuO4 and in Pb55In45 superconductors and Tc inhomogeneities.
Review title: The role of inhomogeneities in the anomalous precursor diamagnetism in HTc
Reviewer: reviewer182
Date: 06 July 2006 at 09:30 GMT.
Comment:
The work reported in this article deals with the fluctuation-induced precursor diamagnetism above Tc in high-temperature superconductors (HTS), and in particular with its magnetic field dependance. Understanding this effect allows to make useful statements about the nature of the puzzling normal phase of the HTS, in particular for the underdoped compounds. The results from Cabo et al. are both theoretical and experimental and support the interpretation of the magnetization anomaly (i.e. non-monotonicity of the H dependence of M(T>Tc,H->0)) in terms of Tc inhomogeneities in the sample that was measured.

The model is based on the "Gaussian Ginzburg-Landau" approach where fluctuations of the order parameter above Tc are treated at the Gaussian level. Analytic expreesions of M(T,H) in the T-H phase diagram have been calculated previously by the group of the authors. Here the new ingredient are Eqs. 1&2 that allow to calculate M(T,H) for the inhomogeneous case. The superconductor is modelled as an ensemble of independant grains the Tc distribution of which follows a Gaussian, the parameters of which (Tc,m and dTc,m) having to be extracted from the fit to the experimemtal data. The key point of the author' methodology is the comparison between a high-Tc sample (underdoped LSCO) and the inhomogeneous low-Tc SC Pb (with various In impurities levels). The latter indeed displays an anomaly in M(T>Tc,H->0) that vanishes in the pure Pb case. The qualitative behaviour of the magnetization M(T,H) in both high and low-Tc compounds is well described by the unique model that nicely reproduces the non-monotonicity of M(T>Tc,H->0)(Figs. 2 and 5), while providing meaningful values for the fit parameters Tc,m and dTc,m (Table I). At the more quantitative level, some discrepancies appear, although they cannot invalidate the full approach. For instance the anomaly peak in M(T>Tc,H->0) is sharper (thiner and higher) in the theoretical curves than in the experimental ones, that is probably the reason why the authors did not merge parts a&c and b&d in Fig.2.

From a more general point of view, this work provides strong arguments in favor of an interpretation of the anamalous precursor diamagnetism in term of Tc inhomogeneities. However this treatment only applies to samples constituted of grains. It would be interesting to see if the anomaly is still present in the case of a monocrystal. The authors also pretend that their approach (assuming a Gaussian fluctuation regime) is sufficient to explain the precursor diamagnetism, and that an interpretation of this phenomenon m in term of critical (or pre-critical) XY-like phase fluctuations, as proposed by other groups, is not necessary. I don't agree totally, maybe the above-mentioned
quantitative discrepancies observed for the diamagnetic peak is due to an incorrect treatment of the fluctuation regime for T->Tc, H->0, which should contain a phase contribution. This question may be answered by making similar experiments with other dopings, so that the intrinsic fluctuation contribution is different.


28. Science-advisor.net review 06040041 (2 readers)    * Rate this comment.
Article reference: Potential-energy (BCS) to kinetic-energy (BEC)-driven pairing in the attractive Hubbard model.
Review title: A recent progress in the understanding of the BCS-BEC crossover
Reviewer: reviewer182
Date: 06 April 2006 at 15:56 GMT.
Comment:

The authors have a long experience in developing novel methods providing a better understandin of the physics contained in the simple quantum Hamiltonians that may describe generic properties of material with strong electronic correlations (Hubbard model for instance). Here they report on the application of the cellular DMFT (DMFT) method to the attractive Hubbard model (AHM) to gain new insights into the smooth crossover between BCS superconductivity and Bose-Einstein condensation (BEC). CDMFT is an improvement of DMFT that should suppress the effect of infinite dimensions on which DMFT is based.

There has been recently an application of DMFT to the BCS-BEC crossover problem which yielded some surprizes (Capone, Keller). The most interesting point (see below why) is a possible first-order phase transition at T=0 (and densitie n different from half-filling) in the normal (metastable) state between a Fermi liquid (weak coupling, U<Uc) and a insolating liquid of bosonic bound pairs for U>Uc. This transition is expected to also affect the finite temperature properties of the model, especially above Tc. Now if we recall that the AHM is one of the simplest model that is able to describe the problematic pseudogap phase of the high Tc superconductore above Tc, then we easily realize that a better understanding of the normal phase of the AHM may also be relevant in this context.

The main result of the paper is that the first-order phase transition obtained with DMFT does not survive in finite dimensions (here D=2). It is replaced by a smooth transition showing however all the expected spectral properties: a pseudogap for small U and a large gap for large Us. I regret that the authors do not discuss more deeply the origins of these properties. Indeed, their study essentially reveals the how the strong coupling gap (~ U for large Uc) becomes a pseudogap in the weak coupling and eventually vanishes in the limit U->0, yielding the metal phase. It is however accepted (Mermin-Wagner theorem) that, at least in D=2, an additional effect affects the spectral properties: the enhanced superconducting fluctuations. The interplay between these two factors contributes to the difficulties in understanding the high-Tc. Adding the effect of fluctuations to CDMFT may certainly open new perspectives in separating the "correlation contribution" (as described here, also present for D>2) from the "order parameter flucutation contribution" that plays a dominant role in D=2 only. Analyzing the pseudogap experiments under this persepective may provide a robust framework because it does not rely on any assumption about the actual mechanism leading to the pairing of the electrons (or holes).


29. Science-advisor.net review 06030040 (4 readers)    * Rate this comment.
Article reference: Non-abelian gauge theories as a consequence of perturbative quantum gauge invariance.
Review title: Interesting approach to quantum gauge invariance
Reviewer: reviewer163
Date: 17 March 2006 at 21:32 GMT.
Comment:

The article of Andreas Aste and Guenter Scharf is a kind of inversion of 't Hooft's proof that gauge theories are renormalizable - presupposing that Lorentz symmetry, gauge invariance/unitary and renormalizability hold (very basic requirements), the authors show that in the case of massless fields, a gauge theory automatically emerges. They introduce the free field version of the Becchi-Rouet-Stora transformation, which has a much simpler structure than the full BRS transformation, and show that this very simple transformation contains the full information about the interacting theory. It is astonishing that these 'simple' observations have not been found in the early times of the development of gauge field theories.


30. Science-advisor.net review 05110033 (3 readers)    * Rate this comment.
Article reference: The pseudogap in high-temperature superconductors: an experimental survey.
Review title: Very good experimental review on the pseudogap in high Tc cuprates.
Reviewer: reviewer101
Date: 10 November 2005 at 02:12 GMT.
Comment: This article review cover many experimental aspects of the pseudogap (=partial gap in the electronic density of states). After a short introduction, the main topics are Angle Resolved Photoemission (ARPES) Tunneling Spectroscopy, Nuclear Magnetic Resonance (NMR), transport properties specific heat, Raman and Magnetic Neutron Scattering.

The d-wave nature of the pseudogap and the superconducting gap is well shown. The review shows clearly that the pseudogap is not an experimental artefact but a common feature to many high Tc superconductors.

It would be nice to have an actualized version of this review including other experimental methods like Nernst effect (Wang et al, cond-mat/0108242) or Hall effect (Matthey et al, cond-mat/0104328 where it seems that an additional crossover temperature T_n or T` is present between the critical temperature Tc and the pseudogap temperature T*. This should help to clarify the problem of the phase diagram of high Tc cuprates (Is the phase diagram compatible with a quantum critical point? etc). And, maybe, a more extended theoretical section with all major approaches could be included as well.

Note: there is a small mistakes in the text of figure 39. The YBCO oxygen doping should be written O_{6+x} in order to match with figure legends and not O_{7-\delta}. x=0.76 is the correct value for the underdoped regime.

31. Science-advisor.net review 05090031 (1 reader)    * Rate this comment.
Article reference: Condensation Energy and High Tc Superconductivity.
Review title: On the contributions to high Tc specific heat
Reviewer: reviewer20
Date: 29 September 2005 at 15:27 GMT.
Comment: The authors extract the critical or singular contribution from the specific heat by substracting a BCS like contribution to the measured specific heat. There is a strong assumption behind this choice: the non-critical state of TI2201 is BCS like. This means that there is something, for example a gap Delta(T), that goes to zero at the critical temperature Tc with a discontinuity in the derivative with respect to temperature T.

This would mean that at Tc, there are two phase transitions: the first is due to this gap Delta(T) and produces the BCS like contribution to the specific heat. The second transition must be then related to an order parameter producing the singular contribution, for example an XY like order parameter.

The authors seem to be aware of this problem: \"The main source of this huge difference is the difficulty in determining the normal thermodynamic quantities.\"

I think that everyone would agree that there is only one phase transition at Tc. Hence, to me, this analysis should be taken with great care.

32. Science-advisor.net review 05090030 (3 readers)    * Rate this comment.
Article reference: The electronic specific heat in the pairing pseudogap regime.
Review title: is it possible to consider the phase transition together with the pseudogap?
Reviewer: reviewer20
Date: 29 September 2005 at 13:12 GMT.
Comment: The most interesting thing in this article is the fact that electronic specific heat from single particles cannot reproduce the wide hump between Tc and T*. The hump can be reproduced very well by a pairing contribution. The doping dependence is correct when fitting experiments. However, the main problem is that there is no superconducting phase transition at Tc. The sharp peak at Tc is not reproduced.

Maybe this model could be improved by introducing considering the phase transition together with pairing fluctuations.

33. Science-advisor.net review 05090022 (1 reader)    * Rate this comment.
Article reference: Transmission of Information and Herd Behavior: an Application to Financial Markets.
Review title: Origin of the fat tail
Reviewer: reviewer22
Date: 26 September 2005 at 21:43 GMT.
Comment: The authors introduce the dynamical version of the Cont and Bouchaud model. This model simulates how agents follow the same information when belonging to the same cluster. Agents that share common information take all the same decision in one step. Because of the clustering, the resulting price market is very fluctuating. Indeed, large cluster cause large fluctuations and so large tails in the distribution of returns.

The fat tail distribution of returns in finance can therefore be explained by these informations clusters where all agents are herding. However, on the point of view of game theory, this simple model cannot explain the reason why it is more profitable to herd than not to herd. Is the profit higher when people are herding? Does herding in financial markets corresponds to the Nash equilibrium?
All these questions remain... One should expect that fat tail distributions are the results of collective behaviour. It is therefore not surprising that this model, which includes large clusters of agents, induce this kind of distribution.

I would avdise to play with this model because of its simplicity. It can be a starting point for a more elaborate model of financial markets.

34. Science-advisor.net review 05090021 (1 reader)    * Rate this comment.
Article reference: Experts’ earning forecasts: bias, herding and gossamer information.
Review title: Herding of financial analysts
Reviewer: reviewer22
Date: 23 September 2005 at 15:23 GMT.
Comment: This article shows real data of financial forecasters. By comparing the error and the relative agreement between forecasters, this article shows that real forecasters tend to agree much more among themselves than with the real data.

35. Science-advisor.net review 05090020 (1 reader)    * Rate this comment.
Article reference: The Physics Behind High-Temperature Superconducting Cuprates: The "Plain Vanilla" Version Of RVB.
Review title: Why always the same story?
Reviewer: reviewer20
Date: 23 September 2005 at 14:16 GMT.
Comment: The authors claims that they can explain the pseudogap phase using their simple theory. I see two problems: they have NO quantitative results, just assumptions, and second, if they only propose a mean-field theory. I hardly believe that a zero temperature theory can be extended at 300 K or 500 K in the pseudogap phase.
The most significant critic has been pointed out in this paper
http://arxiv.org/abs/cond-mat/0312385
Indeed, the authors seems to ignore the experimental phase diagram that has been obtained by many groups: there are two transitions lines in the pseudogap phase, one is T* the transition for the pseudogap itself, and the second one is the transition T' which is believe to be a vortex transition or the point where phases start to be correlated.

36. Science-advisor.net review 05090019 (1 reader)    * Rate this comment.
Article reference: First-Order Pairing Transition and Single-Particle Spectral Function in the Attractive Hubbard Model.
Review title: Question about the first order transition
Reviewer: reviewer20
Date: 23 September 2005 at 14:02 GMT.
Comment: My main problem concerning this article is about the existence of the first-order transition. Since it is well-known that first order transitions may reveal the failure of self-consistent or mean-field approaches. One can doubt about the fact that the pairing transition is first order since DMFT is a mean-field theory. It would nice to have a confirmation of simulations or other methods. Maybe someone could mention some references in the forum section.

37. Science-advisor.net review 05090018 (2 readers)    * Rate this comment.
Article reference: Phase Transition with the Berezinskii--Kosterlitz--Thouless Singularity in the Ising Model on a Growing Network.
Review title: Magnetisation in the 2DXY model?
Reviewer: reviewer20
Date: 23 September 2005 at 13:47 GMT.
Comment: It seems that there is a problem of interpretation in this articel. There is no long range order parameter the BKT phase transition because of the Mermin-Wagner theorem at least in the 2DXY model. The magnetisation M is 0 at all temperatures for the 2DXY model. The magnetisation found in this article $M =exp(-c/(\sqrt{T_c-T})$ could be related to a 3DXY or something like that.
I don't understand the BKT interpretation in this article.






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