Contact and policies

The best way to contact me is by e-mail, though if I am travelling it may take up to a week for me to respond. (Members of the media should see the media page instead.) Due to time limitations, however, I have to decline or severely restrict many e-mail requests, including many of the following:

1. Invitations to give seminars, colloquia, lecture series, or to attend conferences or programs. For work and family reasons, and because of existing commitments and high demand, I am currently declining essentially all invitations to discretionary travel or speaking engagements — especially international travel, and especially events for which substitute speakers are available. Apologies in advance.
2. Invitations to join an editorial board, advisory board, or organizational/scientific committee. Due to heavy workload and existing commitments, I am currently declining all invitations of this nature, including "honorary" or "zero-work" positions.
3. Invitations to publish a monograph, book, or lecture notes. I have no uncommitted book plans at present.
4. Invitations to contribute data to a project. You are welcome to freely use any unpublished material (short stories, lecture notes, code, or slides) on my web page or blog; published material is of course subject to copyright, and source files are usually available on request. I am, however, unable to donate significant time to migrating data, creating new content, or taking on an organizational role for such a project. In particular I cannot write a preface, introduction, or endorsement unless there is a direct personal connection between the publication and myself, and I am almost certainly unable to contribute to montages of contributions by many people. An article I have recently uploaded to the arXiv is usually already submitted to a journal, and I will not be able to offer it elsewhere.
5. Invitations to collaborate. Unfortunately, due to many existing projects, I am not able to consider further collaborations at this time.
6. Submissions to a journal I edit (American Journal of Mathematics, Dynamics of PDE, or Forum of Mathematics). Please see this page. I currently serve as an editor for American Journal of Mathematics, Dynamics of PDE, and Forum of Mathematics.
7. Unsolicited manuscripts (other than for submission to a journal I edit). Due to lack of time and many requests, I cannot read or comment on unsolicited self-authored manuscripts of any kind (such as those relating to prime numbers); these will be discarded without acknowledgment. If your manuscript is already publication-quality, I suggest uploading it to the arXiv instead. For advice on choosing a journal, see this page; for advice on writing papers, see this page.
8. Updates to one of my web pages. I am happy to accept corrections. Note that some older pages, such as my conference list and the local/global well-posedness page, are obsolete and are no longer updated here.
9. Requests for letters of recommendation. I am generally willing to write these when I am already sufficiently familiar with the applicant's work, but require at least a month's notice and very specific information on where, in what format, and by when the letters should be sent. A CV and publication list (or a link to one) is very helpful. Where possible I prefer online systems such as MathJobs to print applications, and I am generally unable to write physical letters while travelling.
10. Requests to referee a paper. I can still devote some time to refereeing, though if a paper is not of major significance, or could be refereed by many others, I am likely to decline or give only a quick opinion. A full report typically takes two to four months, depending on the length of the paper and my schedule.
11. Requests for Java programming code. See this page and this directory for my past experiments with Java, including source code; you are free to use and modify it as long as its provenance is acknowledged. I cannot help with specific Java tasks or homework. The code was written for Java 1.0 and may not be compatible with modern versions.
12. Requests for help with a math problem. I am happy to attempt questions arising directly from one of my papers, books, or classes (please be specific, and include your own thoughts). I also welcome corrections and errata. I cannot, however, assist with other mathematical queries, troubleshoot research projects, speculate on conjectures, or answer homework or course questions not arising from one of my own classes. For general advice on solving problems, see this page; for general queries, try MathOverflow (research-level), the Art of Problem Solving (high-school/undergraduate), the Mathematics Stack Exchange, or the /r/math subreddit.
13. Requests for preprints or papers. Please see my papers and preprints page or search the arXiv. In almost all cases the arXiv version, linked from the papers page, is the most updated version; source files are generally available on request or directly from the arXiv.
14. Requests for books, or questions about books. See my book pages for bibliographic details and errata, and my blog book page for sample chapters and publication status. I cannot provide full-length versions of the books.
15. Requests to exchange links. I do not participate in link exchanges between web pages.
16. Requests for an appointment. I have only a very limited amount of time available for appointments, and give priority to UCLA faculty, staff, and students (particularly my own graduate students and students in my classes). For media-related appointments, please see the media page. Other requests are likely to be declined due to lack of time; please consult my travel schedule and e-mail at least a week in advance.
17. Requests for career advice. Please see my career advice page. Due to lack of time I cannot provide personalized career advice, but you are welcome to comment on that page or its subpages.
18. Requests for prefaces, autographs, inspirational words, or endorsements. I will be declining almost all such requests, especially where I have no direct personal connection to the topic and target audience.
19. Requests for new blog articles. I do not take requests for specific blog topics, nor do I accept unsolicited guest articles or offers of links or content for the blog.
20. Requests for interviews. Please see the media page. In general I decline almost all interviews, including those for school projects.
21. Queries on gifted education. Please see this page. Due to lack of time I cannot provide personalized advice on these issues.
22. Applications for a position at the UCLA mathematics department. Please see the department faculty and graduate admissions pages as appropriate. You are welcome to inform me of your application, but I am usually not involved in admissions and cannot handle materials directly or advise on improving your chances. Note that I do not accept students for graduate study with me until they are already at UCLA and have passed their qualifying exams, and I plan to take on roughly one graduate student a year.
23. Applications for a summer research position, internship, mentorship, CSST, or REU. Unfortunately I do not have the time available to supervise such positions.
24. Offers of an honorary degree, or honorary membership in an organization. This is very flattering, but I do not accept honorary degrees or honorary memberships in organizations with which I have no prior affiliation.

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