413 research outputs found
The Emergence of Anticommuting Coordinates and the Dirac-Ramond-Kostant operators
The history of anticommuting coordinates is decribed.Comment: 14 pages, Contribution to the Proceedings of The Gunnar Nordstr\"om
Symposium on Theoretical Physics - The Physics of Extra Dimension
Maximally Supersymmetric Yang-Mills Theory. The Story of N = 4 Yang-Mills Theory
This is a personally colored account of the history behind N=4 Yang-Mills
Theory.Comment: Talk given at "60 years of Yang-Mills Theory", Singapore May 25-28,
2015. 15 page
Particle Physics as Representations of the Poincare Algebra
Eugene Wigner showed already in 1939 that the elementary particles are
related to the irreducible representations of the Poincare algebra. In the
light-cone frame formulation of quantum field theory one can extend these
representations to depend also on a coupling constant. The representations then
become non-linear and contain the interaction terms which are shown to have
strong uniqueness. Extending the algebra to supersymmetry it is shown that two
field theories stick out, N=4 Yang-Mills and N=8 Supergravity and their higher
dimensional analogues. I also discuss string theory from this starting point.Comment: Lecture presented at the Poincare Symposium held in Brussels on
October 8-9, 200
WTO Constraints on U.S. and EU Domestic Support in Agriculture: The October 2005 Proposals
The USA, the EU and the G-20 submitted proposals on domestic support in the WTO agriculture negotiations in October 2005. This research projects future support, allowances and constraints for the USA and the EU under these proposals. Accounting properly for the de minimis rules generates a "maximum usable components" constraint, which, even when added to the cap on blue, can be more constraining than the new overall commitment. The overall commitment under the U.S. proposal constrains neither the USA nor the EU in the future. However, the overall commitment under the EU and G 20 proposals constrains both the USA and the EU to provide less future overall support than the sum of the cap on blue and maximum usable components. In general the three proposals are weak in constraining future distorting support in the USA and the EU.agriculture, AMS, de minimis, domestic support, overall reduction, WTO, International Relations/Trade,
Classifying, Measuring and Analyzing WTO Domestic Support in Agriculture: Some Conceptual Distinctions
Much confusion permeates discussions of the domestic support provisions of the WTO Agreement on Agriculture and in the ongoing Doha negotiations. The paper clarifies some conceptual distinctions with a view to dispelling some confusion, enhancing communication, and facilitating the representation of domestic support provisions in economic analysis. It distinguishes between classification of policy measures and measurement of support, between measures and support, among measures classified in various categories, between applied support and commitments, and between applied support that counts towards commitments and applied support that does not. It highlights certain issues, including the role of criteria in classifying policy measures (such as those labelled green box or blue box measures), the role of de minimis rules in measuring certain applied support (such as Current Total AMS), and how the time specificity of applied support may complicate analysis of domestic support provisions. It introduces schematic charts to complement the verbal exposition of classification and measurement rules under the Agreement on Agriculture and as suggested in the 2004 Framework of the Doha negotiations on agriculture.WTO, agriculture, domestic support, Doha, AMS, de minimis, commitments, rules., International Relations/Trade,
WTO 2004 Agriculture Framework: Disciplines on Distorting Domestic Support
The July 2004 Agriculture Framework is the basis for negotiations of modalities in agriculture in the WTO. The significant new ideas on domestic support include an Overall Reduction applying to the sum of Total Aggregate Measurement of Support (Total AMS), de minimis AMSs, and blue box payments (i.e., all non-green support), tiered harmonizing reductions of overall distorting support and Total AMS, caps on product-specific AMSs, cap on and criteria for blue box payments, lower de minimis, and review of green box criteria. This paper assesses how several of these provisions might constrain the future (2014) distorting domestic support of USA, EU, Japan, Canada, Brazil, and China. Future support is projected, paying particular attention to U.S. and EU support. The analysis uses a hypothetical 90-80-70-60 reduction scenario to estimate the remaining entitlements to support and calculates the cuts the six Members can accommodate without affecting projected future support. It also estimates the maximum support that can be used within the commitments, considering that simply summing the Total AMS commitment and all de minimis allowances overestimates the amount of support that can be provided (a product's AMS can not at the same time be de minimis and counted in Current Total AMS). The six Members can accommodate large cuts in commitments on overall distorting support and Total AMS. A cut of 75 percent would not bite into the U.S. future support and a 79 percent cut would not constrain future EU-15 support. Large cuts would not force the other four Members to reduce support from what they have notified or provided in recent years. Large cuts will prevent reversals of support reductions. Harmonizing tiered cuts can effectively address the support entitlements of the large subsidizers. Altogether the provisions of the 2004 Framework allow for substantial reductions in distorting support, and the Overall Reduction can be particularly effective. The reduction scenario examined for the six Members reduces their combined usable entitlements to all distorting support by about half (from 148 bill. in 2014) when applied to Total AMS, de minimis, and blue entitlement separately. Applying also the Overall Reduction reduces the combined usable entitlements by a further 65 bill. However, this requires that Members agree to sizeable percentage cuts in the commitments on Overall Reduction and on Total AMS.Agricultural and Food Policy, International Relations/Trade,
Constraining U.S. and EU Domestic Support in Agriculture: The October 2005 WTO Proposals
In October 2005 the USA, EU, and G-20 submitted proposals on domestic support in the WTO agriculture negotiations. We consider the de minimis rules and allowances, project future (2014) distorting support for the USA and the EU-15, calculate the constraints resulting from projected values of production combined with the U.S., EU and G-20 proposals, and compare their effectiveness in constraining components of distorting support and future applied support. The de minimis rules make a significant difference for future allowed support. Under the U.S. proposal the Overall commitment constrains neither the USA nor the EU. Under the EU and especially the G-20 proposals the Overall commitment constrains distorting support to be less than the sum of the cap on blue and the Maximum Usable Components (MUC). The MUC is smaller than the sum of the commitment on Total Aggregate Measurement of Support (TAMS) and all de minimis allowances. Despite seemingly large percentage reductions, the three proposals would impose only very modest, if any, constraints on projected 2014 applied domestic support.agriculture, AMS, de minimis, domestic support, overall reduction, WTO, Agricultural and Food Policy, International Relations/Trade, Q17,
WTO Constraints on U.S. and EU Domestic Support in Agriculture: Assessing the October 2005 Proposals
Proposals on domestic support were submitted in the WTO agriculture negotiations by the USA, the EU, and the G-20 in October 2005, based on the 2004 Framework agreement. This paper pays attention to the de minimis rules and the resulting de minimis allowances and projects future (2014) distorting support for the USA and the EU-15. It calculates the constraints resulting from projected values of production combined with the U.S., EU and G-20 proposals and compares their effectiveness in constraining components of distorting support and the projected future applied support. The de minimis rules make a difference in estimating how much distorting support can be provided in the future. Under the U.S. proposal the Overall commitment does not constrain either the USA or the EU. Under the EU and especially the G-20 proposals the Overall commitment constrains distorting support to be less than the sum of the cap on blue and the maximum usable components. This maximum is smaller than the sum of the commitment on Total Aggregate Measurement of Support (AMS) and the de minimis allowances. The U.S. proposal constrains only one component (Current Total AMS) and this only for the EU. The EU proposal does not constrain projected future applied support in either the USA or the EU. The G-20 proposal constrains the future Current Total AMS for both the USA and the EU. The G-20 proposal constrains projected future Overall distorting support for the EU but not for the USA.Agricultural and Food Policy, International Relations/Trade,
Dirac Equations, Light Cone Supersymmetry, and Superconformal Algebras
After a brief historical survey that emphasizes the role of the algebra
obeyed by the Dirac operator, we examine an algebraic Dirac operator associated
with Lie algebras and Lie algebra cosets. For symmetric cosets, its
``massless'' solutions display non-relativistic supersymmetry, and can be
identified with the massless degrees of freedom of some supersymmetric
theories: N=1 supergravity in eleven dimensions (M-theory), type IIB string
theory in ten and four dimensions, and in four dimensions, N=8 supergravity,
N=4 super-Yang-Mills, and the N=1 Wess-Zumino multiplet. By generalizing this
Dirac operator to the affine case, we generate superconformal algebras
associated with cosets , where contains the {\it space}
little group. Only for eleven dimensional supergravity is simple. This
suggests, albeit in a non-relativistic setting, that these may be the limit of
theories with underlying two-dimensional superconformal structure.Comment: 19 pages, latex, [sprocl]. Contributed article to Golfand's Memorial
Volume, M. Shifman ed., World Scientifi
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