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1. • CommentRowNumber1.
   • CommentAuthorzskoda
   • CommentTimeOct 11th 2013
   • (edited Oct 11th 2013)
   • PermaLink
   Author: zskoda
   Format: MarkdownItexDear all, I have spent few days few weeks ago to create a page called [[topological state of matter]] (and few related pages in $n$Lab and in my private lab). This notion, is according to wikipedia, somewhat wider than more narrow notion of topological order. But I am not an expert. A real expert, seemingly [[Xiao-Gang Wen]] entered the scene first as Anonymous User and changed the page; his 9 references were the main addition, and in recent edits he (or else) edits under his own name. I like that experts join and help. But the edits were a bit unfair. He changed the page name to [[topological order]], what I am not the most happy, though the notions are closely related. Topological order was supposed to be a separate page as wikipedia does it with clear argumentation for it ([wikipedia -- topological order](http://en.wikipedia.org/wiki/Topological_order), [wikipedia -- topological insulator](http://en.wikipedia.org/wiki/Topological_insulator)). He put some of his references into the list of references and changed and biased the idea section; some of those are specialized and I would rather put them under [[quantum Hall effect]] etc. However, he also ERASED a number of reviews and other references of concurrent authors and did not notify about the changes in $n$Forum. I find this a school example of a selfish spammer behaviour. The most $n$POV article, the one by Freed and Moore has been excluded in Mr Wen's edit, among other references with this fate!!!!!!!!!! Urs and Toby have done minor edits in the meantime (Urs added physics menu), effectively approving the spammed state; I would call for more attention when overwriting an Anonymous User! I rolled back the page to version 1 and then repaired some of the damage which this may cause. More careful dealing with vandalism which I found would take too much time. Already this took a precious hour in a day in which I am in a big problem with finishing the things for this week, before travelling away for 2 days. I now created a separate page [[topological state of matter]], where I moved sentences added to the idea section by Mr Wen. Mr Wen created page for himself, where I moved his 9 references till it is decided how to redistribute better; I also added his review to quantum Hall effect (should finally be in an entry on fractional QHE). Mr Wen also created [[symmetry protected trivial order]] and updated [[Levin-Wen model]] which I do not plan to touch; I believe those are valuable additions. I retained the reference by Read and Sachdev, which he added to [[topological state of matter]]. I also returned the table which Urs has put what has been erased in my rollback. On the other hand, I added the reference * Xie Chen, Zheng-Cheng Gu, Zheng-Xin Liu, Xiao-Gang Wen, _Symmetry protected topological orders and the group cohomology of their symmetry group_, [arXiv:1106.4772](http://arxiv.org/abs/1106.4772); A short version in Science __338__, 1604-1606 (2012) [pdf](http://dao.mit.edu/~wen/pub/dDSPTsht.pdf) which is coauthored by Mr Wen (but he did not add it to our $n$Lab) and which is, because of its relation to group cohomology, of prime interest to $n$Lab.

   Dear all, I have spent few days few weeks ago to create a page called topological state of matter (and few related pages in $n$Lab and in my private lab). This notion, is according to wikipedia, somewhat wider than more narrow notion of topological order. But I am not an expert. A real expert, seemingly Xiao-Gang Wen entered the scene first as Anonymous User and changed the page; his 9 references were the main addition, and in recent edits he (or else) edits under his own name. I like that experts join and help. But the edits were a bit unfair.

   He changed the page name to topological order, what I am not the most happy, though the notions are closely related. Topological order was supposed to be a separate page as wikipedia does it with clear argumentation for it (wikipedia – topological order, wikipedia – topological insulator). He put some of his references into the list of references and changed and biased the idea section; some of those are specialized and I would rather put them under quantum Hall effect etc. However, he also ERASED a number of reviews and other references of concurrent authors and did not notify about the changes in $n$Forum. I find this a school example of a selfish spammer behaviour. The most $n$POV article, the one by Freed and Moore has been excluded in Mr Wen’s edit, among other references with this fate!!!!!!!!!! Urs and Toby have done minor edits in the meantime (Urs added physics menu), effectively approving the spammed state; I would call for more attention when overwriting an Anonymous User!

   I rolled back the page to version 1 and then repaired some of the damage which this may cause. More careful dealing with vandalism which I found would take too much time. Already this took a precious hour in a day in which I am in a big problem with finishing the things for this week, before travelling away for 2 days.

   I now created a separate page topological state of matter, where I moved sentences added to the idea section by Mr Wen. Mr Wen created page for himself, where I moved his 9 references till it is decided how to redistribute better; I also added his review to quantum Hall effect (should finally be in an entry on fractional QHE). Mr Wen also created symmetry protected trivial order and updated Levin-Wen model which I do not plan to touch; I believe those are valuable additions. I retained the reference by Read and Sachdev, which he added to topological state of matter. I also returned the table which Urs has put what has been erased in my rollback.

   On the other hand, I added the reference

   • Xie Chen, Zheng-Cheng Gu, Zheng-Xin Liu, Xiao-Gang Wen, Symmetry protected topological orders and the group cohomology of their symmetry group, arXiv:1106.4772; A short version in Science 338, 1604-1606 (2012) pdf

   which is coauthored by Mr Wen (but he did not add it to our $n$Lab) and which is, because of its relation to group cohomology, of prime interest to $n$Lab.

2. • CommentRowNumber2.
   • CommentAuthorxgwen
   • CommentTimeOct 11th 2013
   • PermaLink
   Author: xgwen
   Format: TextI notice the entry about topological phase of matter, which mix the long-range entangled topological order and short-range entangled SPT order. It will cause confusion. So I split the entry into two entries and give them more precise names. I am sorry I did not keep the original entry. Maybe I should just create two new entries. In last twenty yearsn I have worked very hard to gain a clear understanding about gapped quantum metter, and a quite clear picture has been obtained. I strongly feel that this clear picture should be reflected in nLab. I tried to include all the early refs. If I missed any, please do add them, which can be easily done.

   I notice the entry about topological phase of matter, which mix the long-range entangled topological order and short-range entangled SPT order. It will cause confusion. So I split the entry into two entries and give them more precise names.
   
   I am sorry I did not keep the original entry. Maybe I should just create two new entries.
   
   In last twenty yearsn I have worked very hard to gain a clear understanding about gapped quantum metter, and a quite clear picture has been obtained. I strongly feel that this clear picture should be reflected in nLab. I tried to include all the early refs. If I missed any, please do add them, which can be easily done.
3. • CommentRowNumber3.
   • CommentAuthorzskoda
   • CommentTimeOct 11th 2013
   • PermaLink
   Author: zskoda
   Format: MarkdownItexI edited the comment 1, in the meantime, before I noticed your post.

   I edited the comment 1, in the meantime, before I noticed your post.

4. • CommentRowNumber4.
   • CommentAuthorzskoda
   • CommentTimeOct 11th 2013
   • (edited Oct 11th 2013)
   • PermaLink
   Author: zskoda
   Format: MarkdownItexMr Wen, 2, I am happy with the other page [[symmetry protected trivial order]] which you created. $n$Lab is a category theory oriented and the main interest in topological states of matter is as an application of [[topological quantum field theory]], a subject closely related to higher category theory and homotopy theory, which are in prime field of our interest. Thus the broader entries from the point of view of TQFT are the starting point for us. You are welcome to create separate pages for special cases, I hope you can keep rigorous reasoning and explain to us the reasoning behind introducing those subdivisions (I do understand your insistence on long vs. short range); for deeper changes to the material interfering with other contributors please discuss in $n$Forum; issue by issue. I do understand that before the terminology and formalism grew into TQFT-approach that many people had worked on the same physical system with partial understanding of topological effects. However, from the point of view of $n$Lab the real mathematical understanding comes with synthesis in abstract and systematic terms (in our case, e.g. explicit TQFT approach). Of course, every author can feel the parts of the picture seen decade or two earlier. One can have a separate page on prehistory. We can discuss later what to incorporate there.

   Mr Wen, 2, I am happy with the other page symmetry protected trivial order which you created. $n$Lab is a category theory oriented and the main interest in topological states of matter is as an application of topological quantum field theory, a subject closely related to higher category theory and homotopy theory, which are in prime field of our interest. Thus the broader entries from the point of view of TQFT are the starting point for us. You are welcome to create separate pages for special cases, I hope you can keep rigorous reasoning and explain to us the reasoning behind introducing those subdivisions (I do understand your insistence on long vs. short range); for deeper changes to the material interfering with other contributors please discuss in $n$Forum; issue by issue.

   I do understand that before the terminology and formalism grew into TQFT-approach that many people had worked on the same physical system with partial understanding of topological effects. However, from the point of view of $n$Lab the real mathematical understanding comes with synthesis in abstract and systematic terms (in our case, e.g. explicit TQFT approach). Of course, every author can feel the parts of the picture seen decade or two earlier. One can have a separate page on prehistory. We can discuss later what to incorporate there.

5. • CommentRowNumber5.
   • CommentAuthorzskoda
   • CommentTimeOct 11th 2013
   • (edited Oct 11th 2013)
   • PermaLink
   Author: zskoda
   Format: MarkdownItex> I am sorry I did not keep the original entry. Maybe I should just create two new entries. Thank you for cooperating; as far as I am concerned, the apology is accepted. I would however like to see where did Freed-Moore reference for example end in this splitting procedure ? > I strongly feel that this clear picture should be reflected in nLab. We would be very happy if this happens. As long as you strive for mathematically clear and rigorous picture and try to give balanced viewpoint of authors whom you understand, your future additions will be appreciated and may contribute to your effort of disseminating a point of view close to your understanding.

   I am sorry I did not keep the original entry. Maybe I should just create two new entries.

   Thank you for cooperating; as far as I am concerned, the apology is accepted. I would however like to see where did Freed-Moore reference for example end in this splitting procedure ?

   I strongly feel that this clear picture should be reflected in nLab.

   We would be very happy if this happens. As long as you strive for mathematically clear and rigorous picture and try to give balanced viewpoint of authors whom you understand, your future additions will be appreciated and may contribute to your effort of disseminating a point of view close to your understanding.

6. • CommentRowNumber6.
   • CommentAuthorxgwen
   • CommentTimeOct 11th 2013
   • PermaLink
   Author: xgwen
   Format: TextI added/restore the entry on topological order. Moore-Freed's paper is not included since it is about topological order.

   I added/restore the entry on topological order. Moore-Freed's paper is not included since it is about topological order.
7. • CommentRowNumber7.
   • CommentAuthorxgwen
   • CommentTimeOct 11th 2013
   • PermaLink
   Author: xgwen
   Format: TextThe current version of [[topological states of matter]] contain mathematically and physically incorrect statements. [[topological states of matter]] is defined as a a phase of matter which is, at long distance and low energy, described by a topological quantum field theory. But in the examples, topological insulator and quantum spin Hall effect are not described by topological quantum field theory. In 2+1D, topological quantum field theory produce fractional statistics and ground state degeneracy. Topological insulator and quantum spin Hall effect do not produce fractional statistics and ground state degeneracy. They have trivial [[topological order]] and are described by trivial topological quantum field theory (or non topological quantum field theory). Topological insulator and quantum spin Hall effect are examples of [[SPT order]]. The refs Alexei Kitaev, Periodic table for topological insulators and superconductors, Proc. L.D.Landau Memorial Conf. “Advances in Theor. Physics”, June 22-26, 2008, Chernogolovka, Russia, arxiv/0901.2686 (uses K-homology, Bott periodicity etc.) Daniel S. Freed, Gregory W. Moore, Twisted equivariant matter, arxiv/1208.5055 (uses equivariant K-theory) are about gap phases of free fermion systems that are not described by TQFT (ie those free fermion gapped phases have no fractional statistics and ground state degeneracy.) Xie Chen, Zheng-Cheng Gu, Zheng-Xin Liu, Xiao-Gang Wen, Symmetry protected topological orders and the group cohomology of their symmetry group, arXiv:1106.4772; A short version in Science 338, 1604-1606 (2012) pdf is abou gapped phases of interacting boson systems that are not described by TQFT (ie those interacting-boson gapped phases have no fractional statistics and ground state degeneracy.) So those refs should not be here. The topological state of matter defined in this article was well understand in 1980-1990. Those refs are not included.

   The current version of
   topological states of matter contain mathematically and physically incorrect statements.
   
   topological states of matter is defined as a
   a phase of matter which is, at long distance and low energy, described by a topological quantum field theory.
   But in the examples, topological insulator and quantum spin Hall effect are not described by topological quantum field theory.
   In 2+1D, topological quantum field theory produce fractional statistics and ground state degeneracy. Topological insulator and quantum spin Hall effect do not produce fractional statistics and ground state degeneracy. They have trivial topological order and are described by trivial topological quantum field theory (or non topological quantum field theory).
   Topological insulator and quantum spin Hall effect are examples of SPT order.
   
   The refs
   
   Alexei Kitaev, Periodic table for topological insulators and superconductors, Proc. L.D.Landau Memorial Conf. “Advances in Theor. Physics”, June 22-26, 2008, Chernogolovka, Russia, arxiv/0901.2686 (uses K-homology, Bott periodicity etc.)
   Daniel S. Freed, Gregory W. Moore, Twisted equivariant matter, arxiv/1208.5055 (uses equivariant K-theory)
   
   are about gap phases of free fermion systems that are not described by TQFT (ie those free fermion gapped phases have no fractional statistics and ground state degeneracy.)
   
   Xie Chen, Zheng-Cheng Gu, Zheng-Xin Liu, Xiao-Gang Wen, Symmetry protected topological orders and the group cohomology of their symmetry group, arXiv:1106.4772; A short version in Science 338, 1604-1606 (2012) pdf
   
   is abou gapped phases of interacting boson systems that are not described by TQFT (ie those interacting-boson gapped phases have no fractional statistics and ground state degeneracy.)
   
   So those refs should not be here.
   
   The topological state of matter defined in this article was well understand in 1980-1990. Those refs are not included.
8. • CommentRowNumber8.
   • CommentAuthorzskoda
   • CommentTimeOct 11th 2013
   • (edited Oct 11th 2013)
   • PermaLink
   Author: zskoda
   Format: MarkdownItexI added sentence > This entry has some overlap with [[topological state of matter]], however unlike it, it does not include [[symmetry protected trivial order]]. to [[topological order]]. Is this correct ? In each case, we need to make reader aware of the rest of the world.

   I added sentence

   This entry has some overlap with topological state of matter, however unlike it, it does not include symmetry protected trivial order.

   to topological order. Is this correct ?

   In each case, we need to make reader aware of the rest of the world.

9. • CommentRowNumber9.
   • CommentAuthorxgwen
   • CommentTimeOct 11th 2013
   • PermaLink
   Author: xgwen
   Format: Textthe following link may be helpful http://physics.stackexchange.com/questions/70728/reconciling-topological-insulators-and-topological-order I am thinking to include the nices articles Alexei Kitaev, Periodic table for topological insulators and superconductors, Proc. L.D.Landau Memorial Conf. “Advances in Theor. Physics”, June 22-26, 2008, Chernogolovka, Russia, arxiv/0901.2686 (uses K-homology, Bott periodicity etc.) Daniel S. Freed, Gregory W. Moore, Twisted equivariant matter, arxiv/1208.5055 (uses equivariant K-theory) in the SPT order entry, where they partially belong. (The SPT entry is about interacting systems, while the above two refs are mainly about non-interacting fermion systems.)

   the following link may be helpful http://physics.stackexchange.com/questions/70728/reconciling-topological-insulators-and-topological-order
   
   I am thinking to include the nices articles
   Alexei Kitaev, Periodic table for topological insulators and superconductors, Proc. L.D.Landau Memorial Conf. “Advances in Theor. Physics”, June 22-26, 2008, Chernogolovka, Russia, arxiv/0901.2686 (uses K-homology, Bott periodicity etc.)
   Daniel S. Freed, Gregory W. Moore, Twisted equivariant matter, arxiv/1208.5055 (uses equivariant K-theory)
   in the SPT order entry, where they partially belong. (The SPT entry is about interacting systems, while the above two refs are mainly about non-interacting fermion systems.)
10. • CommentRowNumber10.
    • CommentAuthorzskoda
    • CommentTimeOct 11th 2013
    • (edited Oct 11th 2013)
    • PermaLink
    Author: zskoda
    Format: MarkdownItexYes, surely they should be there, if you removed them from [[topological state of matter]] and created [[SPT order]] entry, I really do not understand why the references are not moved along but erased ! Edit: I added Kitaev and Freed/Moore at [[SPT order]].

    Yes, surely they should be there, if you removed them from topological state of matter and created SPT order entry, I really do not understand why the references are not moved along but erased !

    Edit: I added Kitaev and Freed/Moore at SPT order.

11. • CommentRowNumber11.
    • CommentAuthorzskoda
    • CommentTimeOct 11th 2013
    • (edited Oct 11th 2013)
    • PermaLink
    Author: zskoda
    Format: MarkdownItexIs this better at [[topological state of matter]] ? > We include here a phase of matter which is, at long distance and low energy, described by a [[topological quantum field theory]] (invariant under small smooth deformations of space-time) as well as the phases related to [[symmetry protected trivial order]]s.

    Is this better at topological state of matter ?

    We include here a phase of matter which is, at long distance and low energy, described by a topological quantum field theory (invariant under small smooth deformations of space-time) as well as the phases related to symmetry protected trivial orders.

12. • CommentRowNumber12.
    • CommentAuthorxgwen
    • CommentTimeOct 11th 2013
    • PermaLink
    Author: xgwen
    Format: TextI did not include the two refs Alexei Kitaev, Periodic table for topological insulators and superconductors, Proc. L.D.Landau Memorial Conf. “Advances in Theor. Physics”, June 22-26, 2008, Chernogolovka, Russia, arxiv/0901.2686 (uses K-homology, Bott periodicity etc.) Daniel S. Freed, Gregory W. Moore, Twisted equivariant matter, arxiv/1208.5055 (uses equivariant K-theory) in the SPT entry at first, since they are about free fermion systems, while SPT phases are about interaction systems. The math is very different.

    I did not include the two refs
    
    Alexei Kitaev, Periodic table for topological insulators and superconductors, Proc. L.D.Landau Memorial Conf. “Advances in Theor. Physics”, June 22-26, 2008, Chernogolovka, Russia, arxiv/0901.2686 (uses K-homology, Bott periodicity etc.)
    Daniel S. Freed, Gregory W. Moore, Twisted equivariant matter, arxiv/1208.5055 (uses equivariant K-theory)
    
    in the SPT entry at first, since they are about free fermion systems, while SPT phases are about interaction systems. The math is very different.
13. • CommentRowNumber13.
    • CommentAuthorxgwen
    • CommentTimeOct 11th 2013
    • PermaLink
    Author: xgwen
    Format: TextThe current version of topological states of matter contain mathematically and physically incorrect statements. The two examples of topological states of matter ( topological insulator and quantum spin Hall effect ) are not topological states of matter, as define at the begining of the entry. See my comment above.

    The current version of
    topological states of matter contain mathematically and physically incorrect statements.
    
    The two examples of topological states of matter ( topological insulator and quantum spin Hall effect ) are not topological states of matter, as define at the begining of the entry. See my comment above.
14. • CommentRowNumber14.
    • CommentAuthorxgwen
    • CommentTimeOct 11th 2013
    • PermaLink
    Author: xgwen
    Format: TextThe error mentioned above is fixed. The topological state of matter defined by TQFT was well understand in 1980-1990, and the connection to TQFT was mentioned explicitly. Should we include those refs?

    The error mentioned above is fixed. The topological state of matter defined by TQFT was well understand in 1980-1990, and the connection to TQFT was mentioned explicitly. Should we include those refs?
15. • CommentRowNumber15.
    • CommentAuthorxgwen
    • CommentTimeOct 11th 2013
    • PermaLink
    Author: xgwen
    Format: TextI shifted the section "Relation between SPT order and topological order" from [[SPT order]] entry to [[topological states of matter]] entry. [[topological states of matter]] entry contain both SPT order and topological order.

    I shifted the section "Relation between SPT order and topological order" from SPT order entry to topological states of matter entry. topological states of matter entry contain both SPT order and topological order.
16. • CommentRowNumber16.
    • CommentAuthorUrs
    • CommentTimeOct 12th 2013
    • PermaLink
    Author: Urs
    Format: MarkdownItexThanks for all these additions! Zoran, could you maybe remove the "almost SPAM" from the title of this thread? There are genuine good contributions here which I am very happy to see, and the miscommunication seems to be dealt with in a decent way. So it seems rather counterproductive to make strong and capitalized accusations.

    Thanks for all these additions!

    Zoran, could you maybe remove the “almost SPAM” from the title of this thread? There are genuine good contributions here which I am very happy to see, and the miscommunication seems to be dealt with in a decent way. So it seems rather counterproductive to make strong and capitalized accusations.

17. • CommentRowNumber17.
    • CommentAuthorxgwen
    • CommentTimeOct 12th 2013
    • PermaLink
    Author: xgwen
    Format: TextI would like to thank Toby Bartels for editing/improving the [[topological order]] entry.

    I would like to thank Toby Bartels for editing/improving the topological order entry.
18. • CommentRowNumber18.
    • CommentAuthorTobyBartels
    • CommentTimeOct 13th 2013
    • PermaLink
    Author: TobyBartels
    Format: MarkdownItexWell, I just futzed with the links a bit (and formatted the reference list). Generally, we like to have links to articles that don\'t exist but reasonably might; at the same time, you were quite right to put in external links to places where people can actually read about the topics. So I tried to make them both work.

    Well, I just futzed with the links a bit (and formatted the reference list).

    Generally, we like to have links to articles that don't exist but reasonably might; at the same time, you were quite right to put in external links to places where people can actually read about the topics. So I tried to make them both work.

19. • CommentRowNumber19.
    • CommentAuthorzskoda
    • CommentTimeMay 22nd 2015
    • PermaLink
    Author: zskoda
    Format: MarkdownItexAdded reference * Davide Gaiotto, Anton Kapustin, _Spin TQFTs and fermionic phases of matter_, [arxiv/1505.05856](http://arxiv.org/abs/1505.05856)

    Added reference

    • Davide Gaiotto, Anton Kapustin, Spin TQFTs and fermionic phases of matter, arxiv/1505.05856
20. • CommentRowNumber20.
    • CommentAuthorzskoda
    • CommentTimeOct 26th 2015
    • PermaLink
    Author: zskoda
    Format: MarkdownItexNew reference * [[Edward Witten]], _Fermion path integrals and topological phases_, [arxiv/1508.04715](http://arxiv.org/abs/1508.04715) at [[topological phase of matter]].

    New reference

    • Edward Witten, Fermion path integrals and topological phases, arxiv/1508.04715

    at topological phase of matter.

21. • CommentRowNumber21.
    • CommentAuthorzskoda
    • CommentTimeOct 6th 2016
    • (edited Oct 6th 2016)
    • PermaLink
    Author: zskoda
    Format: MarkdownItexA current reference * Class for Physics of the Royal Swedish Academy of Sciences, _Topological phase transitions and topological phases of matter_, Scientific Background on the Nobel Prize in Physics 2016, (2+)26 pages, [pdf](http://www.nobelprize.org/nobel_prizes/physics/laureates/2016/advanced-physicsprize2016.pdf) added at [[topological phase of matter]].

    A current reference

    • Class for Physics of the Royal Swedish Academy of Sciences, Topological phase transitions and topological phases of matter, Scientific Background on the Nobel Prize in Physics 2016, (2+)26 pages, pdf

    added at topological phase of matter.

22. • CommentRowNumber22.
    • CommentAuthorTodd_Trimble
    • CommentTimeOct 6th 2016
    • PermaLink
    Author: Todd_Trimble
    Format: MarkdownItexZoran, speaking of "almost spam": we noticed the other day some unusual page activity at [[Ensifer]] (whose contents were added to and later deleted by said Ensifer, apparently), and that you had performed one of the previous edits. Is Ensifer someone you know? Probably such individuals should be directed to the nForum, if they want to use the nLab to talk about themselves and their projects.

    Zoran, speaking of “almost spam”: we noticed the other day some unusual page activity at Ensifer (whose contents were added to and later deleted by said Ensifer, apparently), and that you had performed one of the previous edits. Is Ensifer someone you know?

    Probably such individuals should be directed to the nForum, if they want to use the nLab to talk about themselves and their projects.

23. • CommentRowNumber23.
    • CommentAuthorzskoda
    • CommentTimeOct 6th 2016
    • (edited Oct 6th 2016)
    • PermaLink
    Author: zskoda
    Format: TextThanks, Todd, for catching this. I do not recall ever editing this page. It looks odd, but if that person has really drive to do some historical research it may be interesting. I do not know what to do about it. IP lookup of Ensifer's 5th version edit seem to be the IP: 202.195.129.247 Decimal: 3401810423 Hostname: 202.195.129.247 ASN: 4538 ISP: China Education and Research Network Center Organization: Suzhou University Services: None detected Type: Broadband Assignment: Static IP Blacklist: Geolocation Information Country: China State/Region: Jiangsu City: Suzhou Latitude: 31.3061879 (31° 18′ 22.28″ N) Longitude: 120.6343821 (120° 38′ 3.78″ E)

    Thanks, Todd, for catching this.
    
    I do not recall ever editing this page. It looks odd, but if that person has really drive to do some historical research it may be interesting. I do not know what to do about it.
    
    IP lookup of Ensifer's 5th version edit seem to be the IP: 202.195.129.247
    Decimal: 3401810423
    Hostname: 202.195.129.247
    ASN: 4538
    ISP: China Education and Research Network Center
    Organization: Suzhou University
    Services: None detected
    Type: Broadband
    Assignment: Static IP
    Blacklist:
    Geolocation Information
    Country: China
    State/Region: Jiangsu
    City: Suzhou
    Latitude: 31.3061879 (31° 18′ 22.28″ N)
    Longitude: 120.6343821 (120° 38′ 3.78″ E)
24. • CommentRowNumber24.
    • CommentAuthorzskoda
    • CommentTimeOct 6th 2016
    • (edited Oct 6th 2016)
    • PermaLink
    Author: zskoda
    Format: MarkdownItexWell, the El Naschie's friend and supporter, ex-regional editor of Chaos, solitons and fractals, and the editor of the Journal of nonlinear sciences and numerical simulation which had special issues celebrating El Naschie, Ji-Huan He is at this university and may not like my internet presence. I hope faking my $n$Lab edit (did this really happen) is not related to this story as this could be a bullshit which is quite hard to deal with. [gScholar](http://scholar.google.com/citations?user=tzM7c2cAAAAJ&hl=en) [sciencewatch](http://archive.sciencewatch.com/inter/aut/2008/08-apr/08aprHe) Edit: <https://ncatlab.org/nlab/show/diff/theory+%28physics%29> is another Ensifer's edit, the same IP, and it is a typographical correction, hence not a malicious edit. Good! Also, at [[kernel]] another probably useful edit: > Kashiwara-Schapira, following the terminology of EGA, uses kernel as a synonym of equalizer (and co-kernel of co-equalizer).

    Well, the El Naschie’s friend and supporter, ex-regional editor of Chaos, solitons and fractals, and the editor of the Journal of nonlinear sciences and numerical simulation which had special issues celebrating El Naschie, Ji-Huan He is at this university and may not like my internet presence. I hope faking my $n$Lab edit (did this really happen) is not related to this story as this could be a bullshit which is quite hard to deal with. gScholar sciencewatch

    Edit: https://ncatlab.org/nlab/show/diff/theory+%28physics%29 is another Ensifer’s edit, the same IP, and it is a typographical correction, hence not a malicious edit. Good!

    Also, at kernel another probably useful edit:

    Kashiwara-Schapira, following the terminology of EGA, uses kernel as a synonym of equalizer (and co-kernel of co-equalizer).

25. • CommentRowNumber25.
    • CommentAuthorTodd_Trimble
    • CommentTimeOct 6th 2016
    • PermaLink
    Author: Todd_Trimble
    Format: MarkdownItexWow. Thanks very much for investigating and replying, Zoran. I've never seen anyone try to assume the identity of a prolific nLab author to perform an edit (which I'll link to, [here](https://ncatlab.org/nlab/revision/Ensifer/3)).

    Wow. Thanks very much for investigating and replying, Zoran. I’ve never seen anyone try to assume the identity of a prolific nLab author to perform an edit (which I’ll link to, here).

26. • CommentRowNumber26.
    • CommentAuthorzskoda
    • CommentTimeOct 6th 2016
    • PermaLink
    Author: zskoda
    Format: MarkdownItexI do not know how this happened, as it seems (see additions I just made to 24) that the contributor is genuine.

    I do not know how this happened, as it seems (see additions I just made to 24) that the contributor is genuine.

27. • CommentRowNumber27.
    • CommentAuthorTobyBartels
    • CommentTimeDec 2nd 2016
    • PermaLink
    Author: TobyBartels
    Format: MarkdownItexNow that the page has been blanked, Todd\'s link in \#25 should go [here](https://ncatlab.org/nlab/revision/empty+153/3). (And if that empty page is ever used for a new article, then it will probably end up yet somewhere else. Unfortunately, Instiki has no way to keep track of revisions under an old name when a page is renamed.)

    Now that the page has been blanked, Todd's link in #25 should go here. (And if that empty page is ever used for a new article, then it will probably end up yet somewhere else. Unfortunately, Instiki has no way to keep track of revisions under an old name when a page is renamed.)