Vaughan Pratt's Home Page.
A one-page account of manmade global warming
We emit CO2, some of it accumulates in the atmosphere, causing Earth's
surface to warm.
starts from 3x168 climate datapoints, for respectively CO2
emissions, atmospheric greenhouse gases, and land temperature, each for the
168 years 1851-2019, and boils them down to just the years 1851, 1977,
which should suffice to give a clear picture of how we've been warming
the planet since 1851.
Climate is (almost) always changing quickly:
An uncertainty principle for climate
Abstract: IPCC's estimates of global climate in 2100 vary widely. We exploit
an uncertainty principle for climate that trades off precision in time for
precision in temperature. Assuming continuation of events, cycles, and
trends since 1850, we obtain a usefully precise estimate of the
extent of warming averaged over the 65 years within 32 years of 2100,
namely 3.0-3.2 °C above preindustrial and 2.1-2.3 °C above today. Those
who view the glass as half full can look forward to half of that period
(suitably weighted) being colder than that while glass-half-empty types will
be more focused on the other half. Variability in phase and duration of
most cycles and events in modern climate makes it difficult to say which
specific years will be the hotter ones.
My AGU19 poster on a closely related topic can be seen here.
Current research interests:
Calibrating centennial climate feedbacks by the Sun:
Are we underestimating the climate feedbacks?
Session A41M, American Geophysical Union Fall
Meeting 2019, Moscone Hall, San Francisco.
The Class CAT of Locally Small Categories as a Functor-Free Framework
for Foundations and Philosophy, talk at Berkeley Math and Philosophy
Sources of Variation in Climate Sensitivity Estimates. Poster,
Global Environmental Change session GC33H: The Rate of Global Warming on
Decadal to Multidecadal Timescales: Hiatus Events, Surge Events, and
Climate Sensitivity. Session GC33H, Posters, Wednesday December 12,
Washington Convention Center, Hall A-C.
April 27: Acceptance speech, University of Sydney 2017 Alumni Award for Innovation and Entrepreneurship.
May 9: "Telling Climate Sensitivity by the Sun", talk at Brian Anderson
Building, Australian National University.
May 25: "Formality and Rigor in Treatments of Global Warming", Summer
School in Formal Techniques, Menlo College.
Magmatic Volatiles as an Amplifier of Centrifugal Volcanism
Perspectives on International Activities in Earth and Space Research and
Supporting Informatics session IN43D, American Geophysical
Union Fall Meeting 2017, Ernest N. Morial Convention Center, New Orleans.
February 5: "Categories with Distinguished Objects", Invited talk, Fields Institute, Toronto.
(more recent version here),
See also these
interviews at this meeting. Their lengths in units of tweets
varied from about one to ten tweets; my three contributions came to
respectively two, four, and two tweets in length. Speakers included
Stephen Wolfram, Dana Scott, Harvey Friedman, Ingrid Daubechies, Jeremy
Avigad, Georges Gonthier, and a number of representatives of the symbolic
computation community. I was the only speaker west
of Chicago, not sure what that says about western mathematics...
My first tweet, attempting to explain quantum computing "better than
[Canadian Prime Minister] Justin Trudeau". (Whereas the state space of 3
bits is a 3-dimensional space with 0-1-valued coordinates, the state space
of 3 qubits is an 8-dimensional space with complex-valued coordinates.)
October 9: Algebras and Bialgebras via Categories with
Distinguished Objects, AMS Western Section Meeting, Denver, Colorado.
November 2: Harmonic Predictive Control as a Variant of
PID Control, tRFMO Model Strategy Evaluation Working Group,
International Commission for the Conservation of Atlantic Tuna, Madrid,
A Centrifugal Volcanism Mechanism for the Atlantic Multidecadal Oscillation
Global Environmental Change session GC13G, American
Geophysical Union Fall Meeting 2016, Moscone Hall, San Francisco.
May 14: "Academic Leadership". Invited talk,
Leadership Development Program, Sydney University International House, Sydney, Australia.
May 26: Euclid's Elements as an Equational Theory.
Seminar, Mathematics Dept., University of Sydney, Sydney, Australia.
August 21: Aristotle, Boole, and Chu: Duality since 350 BC.
Plenary talk, George Boole
Mathematical Sciences Conference, Cork, Ireland. (Conference in honour of Boole's 200th birthday.)
October 12: Aristotle, Boole,
and Categories. Invited paper, Parikh Festschrift, 2015.
Model Complexity of Global Climate:
Could Arrhenius have foreseen the hiatus?
Global Environmental Change session GC43C, American
Geophysical Union Fall Meeting 2015, Moscone Hall, San Francisco.
December 16: An Ekman Transport Mechanism for
the Atlantic Multidecadal Oscillation . Poster, Global Environmental Change session GC21C, American Geophysical
Union Fall Meeting 2014, Moscone Hall, San Francisco.
A homogeneous algebraic definition of Euclidean space,
Talk, Conference BLAST 2013, Chapman University, Orange, CA.
July 18: Weiner's Repetition Finder.
Invited talk, 24th Annual Conference on Combinatorial
Pattern Matching, session "1973 + 40 = 2013", Bad Herrenalb, Germany.
December 13: Reconciling multidecadal land-sea global
temperature with rising CO2.
session GC53C "Understanding 400 ppm Climate: Past, Present and Future", American Geophysical Union Fall
Meeting 2013, Moscone Hall, San Francisco. See also video of oral presentation.
Geodesic spaces: Euclid's five postulates as an equational theory,
starting with the second. Invited talk at
The Constructive in Logic and Applications: A conference
in honour of the 60th Birthday of Sergei Artemov. Video here.
Multidecadal climate to within a millikelvin. Poster,
Global Environmental Change session GC23C, American Geophysical Union Fall meeting 2012, San Francisco.
February 12: Linear Process Algebra.
Invited talk, International Conference on Distributed Computing and Internet Technology, Bhubaneswar, India.
See also slides of talk.
February 15: The Logic of Global Warming. Seminar, TATA
Institute of Fundamental Research, Mumbai, India.
February 15: Euclidean and non-Euclidean algebra.
Seminar, TATA Institute of Fundamental Research, Mumbai, India.
June 14: Euclidean and non-Euclidean algebra.
Seminar, Maths Colloquium, Macquarie University, Sydney, Australia
June 16: Linear Process Algebra.
Colloquium, National Information and Communications Technology Australia (NICTA), Sydney, Australia.
June 17: Linear Process Algebra.
Seminar, School of Information Technology, University of Sydney, Australia.
June 23: The Logic of Global Warming. Seminar,
Australian National University, Canberra, Australia
Structure from sorts, properties, and composition: A minimalist approach
to topoalgebraic structure. Talk, International Conference on Category Theory, UBC, Vancouver, Canada.
October 11: Linear Process Algebra.
Math & CS Colloquium, Santa Clara University, CA.
A three-component analytic model of long-term climate change
. Poster, Global Environmental Change session GC43B, American Geophysical Union Fall meeting 2011, San Francisco.
April 9: Tutorial on Chu spaces. Invited tutorial, Institut
de Recherche et Coordination Acoustique/Musique (IRCAM), Paris, France.
April 9: Presketches.
Talk, IRCAM, Paris, France.
April 13: Presketches.
Seminar, Institute for Information, Logic, and Computation (IILC), University of Amsterdam, Netherlands.
June 2: Topological algebra based on sorts and
properties as free and cofree universes.
Talk, Conference BLAST 2010, University
of Colorado, Boulder, Colorado.
June 5: Geodesic spaces : momentum ::
Groups : symmetry.
Talk, Conference BLAST 2010, University
of Colorado, Boulder, Colorado.
M.Sc. Thesis: Translation
of English into Logical Expressions,
Advisor: Jan B. Hext
Abstract: A computer program to solve Lewis Carroll's syllogisms
is considered. A logical decision method is evolved for dealing with
syllogisms expressed as conjunctive normal form (CNF) propositions. For
the translation of English into CNF, a theory of translation
is presented. A computer program is exhibited which explicitly
embodies each feature of the theory, and produces CNF translations of
Carroll's syllogisms. It is claimed that the translation theory is
the most significant result of the research. A translation approach to
phrase-structure grammars enables their practical value to be studied
more closely. It is shown that the position of phrase-structure
grammars is stronger than that of transformational grammars in a
utilitarian theory, as distinct from an explanatory theory.
Ph.D. Thesis: Shellsort and Sorting Networks,
Advisor: Donald E.
Former Ph.D. Students: