Logic List Mailing Archive
set theory and its neighbours, 25/4, programme (fwd)
Subject: set theory and its neighbours, 25/4, programme
Set theory and its neighbours, 9
This message is to give further information about the nineth
one-day meeting in the series "Set theory and its neighbours",
which will take place on on Wednesday 25th April 2001 at the
London Mathematical Society building, De Morgan House, 57-58
Russell Square, London WC1. The meeting will start at 11am, when
coffee will be available, and the first talk will be at 11.30.
The last talk should finish at roughly 6pm.
The speakers at the meeting will be:
11.30 Russell Barker (Oxford),
Robinson-type relations and the relationship between the k-size
and cardinality of finite structures
Abstract: In this talk I will introduce the notions of L^k, the
restriction of first order logic to k-variables, the
k-size of a model and, two conjectures proposed by
Anuj Dawar. Then I shall define define a special kind of
relation which I shall call a Robinson-type relation and
prove some results about these relations. I shall go on
to give a translation between these relations and the
set of L^3 theories and then use the earlier results
to disprove Dawar's second conjecture.
12.30 Justin Moore (UEA),
What makes the continuum $\aleph_2$?
Abstract: I will discuss some of the past, present, and future of
the statement "The continuum has size $\aleph_2$."
2.30 Peter Koepke (Bonn),
A new fine-structure theory for constructible inner models
Abstract: We present a natural hierarchy for Godel's model L of
constructible sets. The new hierarchy is immediately
adequate for finestructural arguments. This will be
demonstrated by a proof of Jensen's Covering Theorem for L.
Further applications will be discussed.
4.00 Iain Stewart (Leicester)
Finite model theory, computational complexity and program schemes
Abstract: Finite model theory has strong connections with a number
of topics within computer science. For example, assuming
finite structure comes equipped with an ordering of its
elements enables one to logically capture most mainstream
complexity classes. However, one cannot always assume that
one has access to an ordering of the elements of some finite
structure: in database theory, for example, such orderings
are almost always not available. In this talk I shall
outline the concept of a program scheme, which is
essentially a model for computing on arbitrary (not
necessarily ordered) finite structures that sits somewhere
between a Turing machine and a logical formula yet remains
amenable to logical manipulation. I will show that many
classes of program schemes have alternative formulations
as previously-studied logics from finite model theory but
that there are natural classes of program schemes giving
rise to "new" logics with interesting properties.
5.00 Mirna Dzamonja (UEA),
Combinatorial principles that follow from GCH-like cardinal arithmetic
Abstract: We discuss various results showing that at certain
cardinals diamond-like principles follow just from
local GCH-like assumptions on cardinal arithmetic.
More information, including slides from the talks
will be available as we confirm it via the meetings' web-page:
As ever, we hope to keep the meeting fairly relaxed, allowing
plenty of opportunity for informal discussion. We welcome and encourage
anyone to participate. You are very welcome simply to turn up on the
day if you make a late decision. And we hope as many attendees as
possible will be able to come to "DK" for informal discussions at the
end of the talks section of the meeting.
Please do tell anyone about the meeting who you think
may be interested in it. And let us know if you would
like to speak or have ideas for speakers at future meetings.
We are very grateful to the LMS for allowing us to use De Morgan
House as a venue. (De Morgan House is in the south-east corner of
Russell Square, The nearest tube station is Russell Square, but
De Morgan House is also only a short walk from Euston, Euston Square
and Goodge Street stations. See the web-site for maps and similarly
for directions to "DK".)