Quantum aspects of Gauge Theories, Supersymmetry and Unification

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Quantum aspects of Gauge Theories, Supersymmetry
and Unification

• Antoine Van Proeyen
• EC-TMR project, 1996 - 2000

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Plan of talk

• 1. Scientific project and results
• 2. Collaboration between the partners
• 3. Training of young researchers
• 4. Difficulties in running TMR project
• 5. Conclusions

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1.Scientific project and results

• The main ideas of the project programme
• How they developed and grew
• The European dimension

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Keywords of project programme

• Quantization of gravity
• Long-standing puzzle
• guiding the research
• supersymmetry
• Bosons and fermions unified
• maximal symmetry principle
• basic ingredient of
• superstring theory
• non-perturbative results

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Superstring theory

• Elementary particles are string-like objects
• Gravity is automatically included
• All interactions can be unified in one theory

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Non-perturbative aspects

• In standard model, perturbative effects (weak
  coupling) can be calculated with high precision.
  (Scattering of particles, )
• However, when strong coupling is involved,
  calculations in the standard model are
  incomplete (quarks bound together in protons,
  neutrons,... )
• 1994 The Seiberg-Witten result strong coupling
  can be dual to weak coupling
• By changing the description, a strong coupling
  phenomenon can be viewed as a weak-coupling of a
  dual theory.
• In this context, we wrote our project. It was
  realized that investigation into
  non-perturbative effects in string theory could
  open new avenues.

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Main progress
Goal 1
Non-perturbative results Duality
Seiberg-Witten
Milestone 2 and 3
Studied in N2 supersymmetry Special Kähler
geometry
Goal 7
M- theory
p-branes D-branes
11 D supergravity
Goal 8
Type IIA
Milestone 6
E8 x E8 heterotic
Incorporated in string theory Quantum properties
of black holes Gravitational backgrounds
SO(32) heterotic
Type I
Type IIB
Goal 2
adS /CFT duality
String theory explains QCD
Goal 3
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adS / CFT duality

• anti-de Sitter space-time produced by D-branes

• Conformal field theory uses highest bosonic
  space-time symmetry
• we knew usefulness for strings
• Present on border of adS
• Quantum properties of CFT are classical
  properties of the bulk string theory

as massive objects produce curved space in
general relativity
Superstring theory ? field theory
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1. Deconfinement temperature in lattice QCD 2.
Completion of N2 supergravity structure 3.
Characterization of special Kähler Riemann
surfaces 4. Moduli space for hyperinstanton
equations 5. Dual map interior flux tube in
confined phase ? high T deconfined phase 6.
Incorporation of membranes in string theory 7.
Gauge coupling renormalization from superstring
theories 8. Superstring-motivated supergravity
couplings
1997
2
1997
1998
1998
1998
1997
1998
1998
FUTURE
1998
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European dimension

• Most of the previous results are world-wide
  results. We contributed to the general knowledge.
• Basic ingredients are of European origin
• supergravity
• strings
• membranes
• In the U.S. many new ideas have grown out of this
• although many important contributors are former
  Europeans
• The TMR network gave the opportunity for good
  collaborations which contributed significantly
  and timely to these advances
• profiting from available basic knowledge
• This keeps European physics at the forefront of
  research in theoretical high energy physics

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2. Collaboration between partners

• Structure of network
• associated contractors and subcontractors
• meetings and joint efforts
• workshops webpage
• overview of joint publications
• how collaborations originate and develop
• and lessons to be drawn
• connections to industry
• use of the budget

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Structure of the network
Copenhagen
Groningen
London I.C.
Utrecht
Brussel
Berlin H.U.
Leuven
Bonn
Paris ENS
München L.M.
München T.U.
Neuchâtel
9 main nodes
Torino U. Torino Pol.
Milano
Trieste Sissa
Padova
Genova
10 subcontractors
Frascati
Napoli
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Meetings and joint efforts

• Scientific workshops
• London, July 1996
• Neuchâtel, Sept. 1997
• Corfu, Sept. 1998
• Paris, 1999
• Organizational meetings
• Leuven, Jan. 1997
• Torino, Jan. 1998
• Homepage for exchanging information
• Practical information, with protected info for
  contact persons
• Exchange of scientific plans, discussion groups,
  ...

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Overview of 63 joint publications
Proceedings of workshops London and Neuchâtel
(subcontractors included in their main node)
29 publications involve young researchers
employed by the network
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How collaborations originate and develop
We believe this to be an essential difference
with many other TMR projects

• Differently from projects based on experiments,
  observations, statistics, , we can not
  pre-arrange or enforce collaborations.
• Researchers think individually how the evolution
  of the general developed ideas fit into their own
  knowledge and expertise.
• They discuss this with colleagues who may have
  other knowledge but similar interests.
• This may lead to a common plan for those
  researchers.
• This may be somewhat similar to a large scale
  plan in other sciences.
• Discussing results gives often rise to new plans.

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Thus ... we should create the opportunities

• allowing researchers to discuss
• giving them good information on general progress
• giving occasions to collaborate
• In particular
• young researchers travelling to and from various
  institutes leads to exchange of information and
  possibilities for combining knowledge
• remember 29/63 joint publications involve young
  researchers
• staff members have a good overview of various
  lines of research due to their experience
• previous work, contacts, knowledge of older
  results, ...

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For the TMR network

• We tried with exchange of information in
  web-pages
• More useful are the workshops, and frequent
  visits, made possible by the network resources.
• However
• we can not demand that each visit results in a
  publication.
• The list of joint publications is not the
  complete output of the invested resources
• many articles are due to such exchanges although
  at the end they are written by researchers in one
  institute.

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Further remark on international contacts

• we can not enforce that collaborations are inside
  the network.
• The necessary frequent travelling leads to
  contacts with researchers
• in other TMR networks
• in American or other institutes
• In many instances that has lead to even more
  fruitful exchanges of information and
  publications related to the network programme.
• Although they do not classify as joint
  publication.
• We can and should not try to restrict these
  collaborations

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Connections to industry

• Tangential to our research
• Computer software
• Mathematica development
• preprint archives
• unexpectedly seeding new technology developments
• e.g. the Web

Postdoctoral researchers easily find positions in
industry. Industry seems to like the creative
thinking which is developed by our researchers
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Use of budget
to be distributed
see later
Neuchâtel not included
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Already spent on 1/7/98...

• A according to appointments, completely fixed,
  see below
• D according to conferences
• some difficulties see below.

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3. Training of young researchers

• appointments
• applications
• decisions
• complete plan
• training methods

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Applications

• Positions announced on various web-sites
• Candidates had to fill form on web, and letters
  of recommendation were available to committee
  members by secured webpages.

We got in autumn 1996 and in autumn 1997 twice
about 90 candidates.
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Decisions

• Committee with representatives of all the nodes
  took decisions
• in order to guarantee good quality for all
  positions
• to be sure that they fit in the network programme
• to stimulate exchanges of good candidates between
  network institutions (see above
  collaborations)
• Some redistribution of the budget was necessary
• differences in salary and taxation in different
  countries
• PS first year no postdocs according to plan (no
  time to organize)
• second year only a minimal number
• (not enough top quality researchers available
  salary problems)

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Complete plan
Names and dates for all envisaged months are
decided
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Training methods

• 1) Participation to the research groups.
• 2) In yearly network meetings, lecturers give an
  introductory talk, and in the afternoon a
  discussion session is organized where questions
  of these young researchers come first.
• 3) They deliver a substantial part of the
  research talks in the network meetings.
• 4) We organize discussion groups on recent
  developments.
• 5) Lecturers in the institutes give extensive
  series of lectures aimed at the younger people.
• 6) They are sent to schools and workshops.

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4. Difficulties encountered in running TMR project

• structure of collaborations, changing contacts
• other European
• non-European
• differences in salaries of postdocs
• less favoured regions
• advancing payments
• young researchers participating in summer schools

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Structure of collaborations, changing contacts

• We form a group of institutes in Europe with
  frequent contacts, but are not isolated.
• Ideas for collaborations can not be scheduled
• In some cases, other collaborations can be more
  useful
• We can and should not try to restrict these
  collaborations

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Salaries of postdocs

• There was a big difference in salaries for
  postdocs in various countries.
• Starting with the salaries in use in different
  countries, there was a difference of a factor 3.
• ? difficulties in finding good postdocs
• especially in Italy
• We shifted parts of the budget to remedy, and
  changed plans on number of months in various
  countries (even augmenting total number of
  months)
• Now the difference is reduced to factor 1.8

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Less favoured regions

• It was difficult to find a suitable postdoc
  candidate for Napoli
• Solution a researcher of Napoli will go to
  Copenhagen, transferring the corresponding budget
  from Napoli to Copenhagen.

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Advancing payments

• In Italy it is difficult to get money in advance
  from the universities.
• Some universities, however, did succeed to get an
  advance payment. Others can only spend what they
  already got as advance payment !

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Young researchers participating in summer schools

• As mentioned, summer schools are excellent
  opportunities for young researchers to get
  training
• The rules say that costs for workshops and
  conferences can only be charged, when
  representing the network, i.e. they have to
  deliver a talk
• Young researchers are not invited to give talks

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5. Conclusions

• Scientifically, a big step is set in
  understanding non-perturbative structure, and
  relations between strings and field theory
• Continuation of research becomes clear due to
  recognition of dualities, e.g. adS / CFT
• Structure of collaborations should be flexible

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• Plan for employment of young researchers is
  complete
• 387 months 20 months added by universities
• They have already contributed to 29 / 63 joint
  publications
• The EC - TMR network is an opportunity for
  European researchers to continue presence at the
  forefront, exploiting obtained basic knowledge.