Witt vectors, foliations, and absolute de Rham cohomology

This conference will take place November 22-26, 2010, at Nagoya University. It is meant to bring together experts in several areas related (currently or potentially) to the topics named in the title, with the aim of identifying feasible concrete steps to take towards building an absolute de Rham cohomology (a de Rham cohomology theory for arithmetic motives which provides a spectral interpretation of L-functions). Some topics which will be represented at the conference include the following.

The Nagoya University math department has an alternate web site for the conference.

The group photo is now posted here (warning: large file).

Information packet

The organizers have prepared an information packet for participants. It includes: For best results, open with Adobe Reader with Japanese language support installed. We recommend having either a printout or an electronic copy of this document with you when you arrive. (Navigating the Nagoya train station is tricky; this photo indicates the Sakurada side exit.)

Special note: on Monday morning, Thomas Geisser will lead a group from the Hotel Trusty Nagoya to the university, departing promptly at 8:45 AM.

Some other possibly helpful links:


The schedule of lectures is posted here. For those lectures given using a computer, see the schedule page for links to PDF files of the slides.


The list of confirmed participants is posted here.


If you were promised reimbursement for travel and/or local expenses, please follow the following instructions.

Other practical details

These remarks are largely superseded by the information packet; see above.

We have negotiated a room rate of JPY5500/night at the Hotel Trusty Nagoya in downtown Nagoya, near the Fushimi subway station (not to be confused with the nearby Hotel Trusty Nagoya Sakae). The subway trip to the university takes 25-30 minutes and costs JPY500 for a round trip. To reserve a room, please first register (by contacting the organizers), then email kozaki@math.nagoya-u.ac.jp (and cc Lars) with your travel dates. If you decide to stay elsewhere, please let us know that as well. If you already made a reservation, please check the list of hotel reservations and email Kozaki-san if you find any mistakes.

The recommended airport is Nagoya (NGO). From there, it is an easy train ride (30 minutes; JPY1,400 one way) to downtown. Another option is to travel by train from Tokyo Narita (NRT), taking an express train to central Tokyo and then a bullet train (shinkansen) to Nagoya. This takes about 3 hours and costs JPY13,490 for a one-way combined ticket (available at the airport). Most signage at trains, stations, and airports includes both Japanese and Latin characters.

According to this list, most participants can enter Japan without a visa. Otherwise, contact the organizers for assistance (e.g., a formal letter of invitation).

While credit cards are accepted widely, some transactions in Japan (e.g., buying subway tickets) still require cash. In principle, most ATMs should accept foreign bank cards, but your mileage may vary. We recommend obtaining cash at one of the banks at the airport (either from an ATM or by exchanging cash).

The lecture rooms have blackboards (or whiteboards) and laptop projectors with standard VGA connections (if you use a Mac, please bring a DVI-VGA converter). The department can also provide a document camera, which can be used in place of an overhead projector using plain paper slides.


The organizing committee consists of:

Financial support has been provided by DARPA (the US Defense Advanced Research Projects Agency) via grant HR0011-09-1-0048, and by NSF (the US National Science Foundation) via CAREER grant DMS-0545904. Funding for travel to/from the US is subject to US government regulations concerning foreign flag carriers.