Focaliser sur:
Tous les jours
8 nov. 2017
9 nov. 2017
10 nov. 2017
Indico style
Indico style - inline minutes
Indico style - numbered
Indico style - numbered + minutes
Indico Weeks View
Retour à l'affichage de la conférence
Choisissez le fuseau horaire
Utiliser le fuseau horaire de l'événement/catégorie
Veuillez spécifier un fuseau horaire
Africa/Abidjan
Africa/Accra
Africa/Addis_Ababa
Africa/Algiers
Africa/Asmara
Africa/Bamako
Africa/Bangui
Africa/Banjul
Africa/Bissau
Africa/Blantyre
Africa/Brazzaville
Africa/Bujumbura
Africa/Cairo
Africa/Casablanca
Africa/Ceuta
Africa/Conakry
Africa/Dakar
Africa/Dar_es_Salaam
Africa/Djibouti
Africa/Douala
Africa/El_Aaiun
Africa/Freetown
Africa/Gaborone
Africa/Harare
Africa/Johannesburg
Africa/Juba
Africa/Kampala
Africa/Khartoum
Africa/Kigali
Africa/Kinshasa
Africa/Lagos
Africa/Libreville
Africa/Lome
Africa/Luanda
Africa/Lubumbashi
Africa/Lusaka
Africa/Malabo
Africa/Maputo
Africa/Maseru
Africa/Mbabane
Africa/Mogadishu
Africa/Monrovia
Africa/Nairobi
Africa/Ndjamena
Africa/Niamey
Africa/Nouakchott
Africa/Ouagadougou
Africa/Porto-Novo
Africa/Sao_Tome
Africa/Tripoli
Africa/Tunis
Africa/Windhoek
America/Adak
America/Anchorage
America/Anguilla
America/Antigua
America/Araguaina
America/Argentina/Buenos_Aires
America/Argentina/Catamarca
America/Argentina/Cordoba
America/Argentina/Jujuy
America/Argentina/La_Rioja
America/Argentina/Mendoza
America/Argentina/Rio_Gallegos
America/Argentina/Salta
America/Argentina/San_Juan
America/Argentina/San_Luis
America/Argentina/Tucuman
America/Argentina/Ushuaia
America/Aruba
America/Asuncion
America/Atikokan
America/Bahia
America/Bahia_Banderas
America/Barbados
America/Belem
America/Belize
America/Blanc-Sablon
America/Boa_Vista
America/Bogota
America/Boise
America/Cambridge_Bay
America/Campo_Grande
America/Cancun
America/Caracas
America/Cayenne
America/Cayman
America/Chicago
America/Chihuahua
America/Ciudad_Juarez
America/Costa_Rica
America/Creston
America/Cuiaba
America/Curacao
America/Danmarkshavn
America/Dawson
America/Dawson_Creek
America/Denver
America/Detroit
America/Dominica
America/Edmonton
America/Eirunepe
America/El_Salvador
America/Fort_Nelson
America/Fortaleza
America/Glace_Bay
America/Goose_Bay
America/Grand_Turk
America/Grenada
America/Guadeloupe
America/Guatemala
America/Guayaquil
America/Guyana
America/Halifax
America/Havana
America/Hermosillo
America/Indiana/Indianapolis
America/Indiana/Knox
America/Indiana/Marengo
America/Indiana/Petersburg
America/Indiana/Tell_City
America/Indiana/Vevay
America/Indiana/Vincennes
America/Indiana/Winamac
America/Inuvik
America/Iqaluit
America/Jamaica
America/Juneau
America/Kentucky/Louisville
America/Kentucky/Monticello
America/Kralendijk
America/La_Paz
America/Lima
America/Los_Angeles
America/Lower_Princes
America/Maceio
America/Managua
America/Manaus
America/Marigot
America/Martinique
America/Matamoros
America/Mazatlan
America/Menominee
America/Merida
America/Metlakatla
America/Mexico_City
America/Miquelon
America/Moncton
America/Monterrey
America/Montevideo
America/Montserrat
America/Nassau
America/New_York
America/Nome
America/Noronha
America/North_Dakota/Beulah
America/North_Dakota/Center
America/North_Dakota/New_Salem
America/Nuuk
America/Ojinaga
America/Panama
America/Paramaribo
America/Phoenix
America/Port-au-Prince
America/Port_of_Spain
America/Porto_Velho
America/Puerto_Rico
America/Punta_Arenas
America/Rankin_Inlet
America/Recife
America/Regina
America/Resolute
America/Rio_Branco
America/Santarem
America/Santiago
America/Santo_Domingo
America/Sao_Paulo
America/Scoresbysund
America/Sitka
America/St_Barthelemy
America/St_Johns
America/St_Kitts
America/St_Lucia
America/St_Thomas
America/St_Vincent
America/Swift_Current
America/Tegucigalpa
America/Thule
America/Tijuana
America/Toronto
America/Tortola
America/Vancouver
America/Whitehorse
America/Winnipeg
America/Yakutat
Antarctica/Casey
Antarctica/Davis
Antarctica/DumontDUrville
Antarctica/Macquarie
Antarctica/Mawson
Antarctica/McMurdo
Antarctica/Palmer
Antarctica/Rothera
Antarctica/Syowa
Antarctica/Troll
Antarctica/Vostok
Arctic/Longyearbyen
Asia/Aden
Asia/Almaty
Asia/Amman
Asia/Anadyr
Asia/Aqtau
Asia/Aqtobe
Asia/Ashgabat
Asia/Atyrau
Asia/Baghdad
Asia/Bahrain
Asia/Baku
Asia/Bangkok
Asia/Barnaul
Asia/Beirut
Asia/Bishkek
Asia/Brunei
Asia/Chita
Asia/Choibalsan
Asia/Colombo
Asia/Damascus
Asia/Dhaka
Asia/Dili
Asia/Dubai
Asia/Dushanbe
Asia/Famagusta
Asia/Gaza
Asia/Hebron
Asia/Ho_Chi_Minh
Asia/Hong_Kong
Asia/Hovd
Asia/Irkutsk
Asia/Jakarta
Asia/Jayapura
Asia/Jerusalem
Asia/Kabul
Asia/Kamchatka
Asia/Karachi
Asia/Kathmandu
Asia/Khandyga
Asia/Kolkata
Asia/Krasnoyarsk
Asia/Kuala_Lumpur
Asia/Kuching
Asia/Kuwait
Asia/Macau
Asia/Magadan
Asia/Makassar
Asia/Manila
Asia/Muscat
Asia/Nicosia
Asia/Novokuznetsk
Asia/Novosibirsk
Asia/Omsk
Asia/Oral
Asia/Phnom_Penh
Asia/Pontianak
Asia/Pyongyang
Asia/Qatar
Asia/Qostanay
Asia/Qyzylorda
Asia/Riyadh
Asia/Sakhalin
Asia/Samarkand
Asia/Seoul
Asia/Shanghai
Asia/Singapore
Asia/Srednekolymsk
Asia/Taipei
Asia/Tashkent
Asia/Tbilisi
Asia/Tehran
Asia/Thimphu
Asia/Tokyo
Asia/Tomsk
Asia/Ulaanbaatar
Asia/Urumqi
Asia/Ust-Nera
Asia/Vientiane
Asia/Vladivostok
Asia/Yakutsk
Asia/Yangon
Asia/Yekaterinburg
Asia/Yerevan
Atlantic/Azores
Atlantic/Bermuda
Atlantic/Canary
Atlantic/Cape_Verde
Atlantic/Faroe
Atlantic/Madeira
Atlantic/Reykjavik
Atlantic/South_Georgia
Atlantic/St_Helena
Atlantic/Stanley
Australia/Adelaide
Australia/Brisbane
Australia/Broken_Hill
Australia/Darwin
Australia/Eucla
Australia/Hobart
Australia/Lindeman
Australia/Lord_Howe
Australia/Melbourne
Australia/Perth
Australia/Sydney
Canada/Atlantic
Canada/Central
Canada/Eastern
Canada/Mountain
Canada/Newfoundland
Canada/Pacific
Europe/Amsterdam
Europe/Andorra
Europe/Astrakhan
Europe/Athens
Europe/Belgrade
Europe/Berlin
Europe/Bratislava
Europe/Brussels
Europe/Bucharest
Europe/Budapest
Europe/Busingen
Europe/Chisinau
Europe/Copenhagen
Europe/Dublin
Europe/Gibraltar
Europe/Guernsey
Europe/Helsinki
Europe/Isle_of_Man
Europe/Istanbul
Europe/Jersey
Europe/Kaliningrad
Europe/Kirov
Europe/Kyiv
Europe/Lisbon
Europe/Ljubljana
Europe/London
Europe/Luxembourg
Europe/Madrid
Europe/Malta
Europe/Mariehamn
Europe/Minsk
Europe/Monaco
Europe/Moscow
Europe/Oslo
Europe/Paris
Europe/Podgorica
Europe/Prague
Europe/Riga
Europe/Rome
Europe/Samara
Europe/San_Marino
Europe/Sarajevo
Europe/Saratov
Europe/Simferopol
Europe/Skopje
Europe/Sofia
Europe/Stockholm
Europe/Tallinn
Europe/Tirane
Europe/Ulyanovsk
Europe/Vaduz
Europe/Vatican
Europe/Vienna
Europe/Vilnius
Europe/Volgograd
Europe/Warsaw
Europe/Zagreb
Europe/Zurich
GMT
Indian/Antananarivo
Indian/Chagos
Indian/Christmas
Indian/Cocos
Indian/Comoro
Indian/Kerguelen
Indian/Mahe
Indian/Maldives
Indian/Mauritius
Indian/Mayotte
Indian/Reunion
Pacific/Apia
Pacific/Auckland
Pacific/Bougainville
Pacific/Chatham
Pacific/Chuuk
Pacific/Easter
Pacific/Efate
Pacific/Fakaofo
Pacific/Fiji
Pacific/Funafuti
Pacific/Galapagos
Pacific/Gambier
Pacific/Guadalcanal
Pacific/Guam
Pacific/Honolulu
Pacific/Kanton
Pacific/Kiritimati
Pacific/Kosrae
Pacific/Kwajalein
Pacific/Majuro
Pacific/Marquesas
Pacific/Midway
Pacific/Nauru
Pacific/Niue
Pacific/Norfolk
Pacific/Noumea
Pacific/Pago_Pago
Pacific/Palau
Pacific/Pitcairn
Pacific/Pohnpei
Pacific/Port_Moresby
Pacific/Rarotonga
Pacific/Saipan
Pacific/Tahiti
Pacific/Tarawa
Pacific/Tongatapu
Pacific/Wake
Pacific/Wallis
US/Alaska
US/Arizona
US/Central
US/Eastern
US/Hawaii
US/Mountain
US/Pacific
UTC
Sauver
Europe/Paris
Français
Deutsch (Deutschland)
English (United Kingdom)
English (United States)
Español (España)
Français (France)
Italiano (Italia)
Polski (Polska)
Português (Brasil)
Türkçe (Türkiye)
Čeština (Česko)
Монгол (Монгол)
Українська (Україна)
中文 (中国)
S'authentifier
Infrared QCD
de
mercredi 8 novembre 2017 (08:30)
à
vendredi 10 novembre 2017 (15:30)
lundi 6 novembre 2017
mardi 7 novembre 2017
mercredi 8 novembre 2017
09:00
QCD 2- and 3-points Green functions: from lattice results to phenomenology (45+15)
-
José Rodriguez-Quintero
(
Huelva University
)
QCD 2- and 3-points Green functions: from lattice results to phenomenology (45+15)
José Rodriguez-Quintero
(
Huelva University
)
09:00 - 10:00
Room: 483A - Malevitch
10:00
Coffee break
Coffee break
10:00 - 10:30
Room: 483A - Malevitch
10:30
Results for Yang-Mills vacuum correlation functions in the Landau gauge from equations of motion (45+15)
-
Markus Huber
(
Graz University
)
Results for Yang-Mills vacuum correlation functions in the Landau gauge from equations of motion (45+15)
Markus Huber
(
Graz University
)
10:30 - 11:30
Room: 483A - Malevitch
Recent results for Yang-Mills correlation functions in the Landau gauge from equations of motion of 1PI and 3PI effective actions are reviewed. The status of the truncation dependence is discussed on the basis of results for nonprimitively divergent correlation functions and for the three-dimensional case. Special emphasis is put on the renormalization of the underlying equations and perturbative resummation.
11:30
Landau-gauge Yang-Mills correlation functions from the functional renormalization group (45+15)
-
Mario Mitter
(
Brookhaven National Laboratory
)
Landau-gauge Yang-Mills correlation functions from the functional renormalization group (45+15)
Mario Mitter
(
Brookhaven National Laboratory
)
11:30 - 12:30
Room: 483A - Malevitch
12:30
Lunch
Lunch
12:30 - 14:00
Room: 483A - Malevitch
14:00
Variational approach to gauge theory (50+10)
-
Hugo Reinhardt
(
Tübingen University
)
Variational approach to gauge theory (50+10)
Hugo Reinhardt
(
Tübingen University
)
14:00 - 15:00
Room: 483A - Malevitch
I will review the covariant variational approach to Yang-Mills theory in Landau gauge and compare it with the Hamiltonian approach. First I will treat the vacum sector. Then I will study the deconfinement phase transition by calculating the Polyakov loop potential.
15:00
Taming Gribov copies via the horizon restriction: done and to do (50+10)
-
David Dudal
(
Leuven University
)
Taming Gribov copies via the horizon restriction: done and to do (50+10)
David Dudal
(
Leuven University
)
15:00 - 16:00
Room: 483A - Malevitch
A possible way to deal with (small) Gribov copies in the Landau gauge is to restrict the domain of integration of the gauge field variables. Such pioneering work was carried out by Gribov himself at leading order, and improved upon to all orders by Zwanziger, an effort culminating in an effective GZ action with dynamical mass scale. We briefly review this construction, using the inverse ghost propagator as “diagnostic tool” and we mention some underlying assumptions. A major shortcoming of the original effective action was the incompatibility with BRST invariance. Recent insights allowed to reformulate it into a BRST symmetric version, thereby also opening the road to generalizing the Gribov-Zwanziger approach to other classes of gauges. We pay particular attention to the linear covariant gauge. We discuss how dynamical effects can alter the action, resulting in the formation of (BRST invariant) d=2 condensates. A shortcoming of the current approach is that these dynamical mass scales are for now obtained by fitting to lattice data, and we propose a strategy to search for self-consistent gap equations. It remains to be seen whether such scales will be only qualitatively, or also quantitatively compatible with lattice data. At last, we briefly turn to the finite T extension when the Polyakov loop is added to the model via a temporal background gauge field (see other talks). We discuss and illustrate how previous work (using the GZ original action) is at odds with background gauge invariance, a fact under current remediation as this can be related to the lack of BRST invariance. Though, even this improvement leaves important challenges, also present in other approaches (see also other talks).
16:00
Coffee break
Coffee break
16:00 - 16:30
Room: 483A - Malevitch
16:30
Extracting infrared properties of QCD from the Curci-Ferrari model (45)
-
Matthieu Tissier
(
Université Pierre et Marie Curie
)
Extracting infrared properties of QCD from the Curci-Ferrari model (45)
Matthieu Tissier
(
Université Pierre et Marie Curie
)
16:30 - 17:15
Room: 483A - Malevitch
It is often believed that the infrared regime of QCD is nonperturbative. This is partly based on the fact that standard perturbation theory predicts a coupling constant which diverges at a finite (infrared) momentum scale. However lattice simmulations show no clue of such a behavior. Instead, the coupling constant is found to be bounded by a constant of order 1, which could be dealt with in perturbation theory. We review on a phenomenological approach which consists in adding to the standard Faddeev-Popov action a gluon mass (this model was introduced by Curci and Ferrari in the 70's). The model has good properties in the infrared regim and the coupling constant remains finite down to arbitrary small momentum scale, as seen in lattice simulations. We review on the systematic comparison that was performed between the 1-loop calculation in this model and lattice simulation. We finally discuss on possible origins for the gluon mass
17:15
Discussion: vacuum
Discussion: vacuum
17:15 - 18:30
Room: 483A - Malevitch
jeudi 9 novembre 2017
09:00
Analytical study of Yang-Mills theory from first principles by a massive expansion (45+15)
-
Fabio Siringo
(
Catania University
)
Analytical study of Yang-Mills theory from first principles by a massive expansion (45+15)
Fabio Siringo
(
Catania University
)
09:00 - 10:00
Room: 483A - Malevitch
Pure Yang-Mills theory is studied by perturbation theory, using an unconventional expansion with a massive free-particle gluon propagator. The exact Faddev-Popov Lagrangian is considered in a generic linear covariant gauge. The Gaussian effective potential is shown to be gauge invariant and minimal at a massive vacuum, providing a variational argument for mass generation. Loop expanding around the optimal massive vacuum, a massive expansion is recovered, yielding dressed propagators that are in very good agreement with the data of lattice simulations in the Landau gauge. No spurious counterterms or parameters are required since all the mass divergences are canceled exactly in the expansion. At one loop, the propagators are analytic functions and can be easily continued to the whole complex plane, predicting the existence of complex poles for the gluon. Because of the finite damping rate, the gluon is canceled from the asymptotic states, yielding a microscopic proof of confinement. At finite temperature, the same variational argument provides an optimal mass that depends on temperature. A weak first order transition is observed at T_c=255 MeV where the optimal mass is discontinuous. The equation of state is studied and found in good quantitative agreement with the lattice data, from first principles and without any free parameter. The poles of the gluon propagator are studied as functions of temperature and a crossover scenario is found, with a short intrinsic lifetime of the quasi-gluon below T_c and an almost linear damping rate above T_c, as expected by standard perturbation theory in the high temperature limit.
10:00
Some applications of Renormalization Group Optimized perturbation at zero and finite temperature (45+15)
-
Jean-Loïc Kneur
(
Montpellier University
)
Some applications of Renormalization Group Optimized perturbation at zero and finite temperature (45+15)
Jean-Loïc Kneur
(
Montpellier University
)
10:00 - 11:00
Room: 483A - Malevitch
I will illustrate how the recently developed renormalization group optimized perturbation theory (RGOPT) resums perturbative expansions in vacuum or thermal field theories. For zero temperature QCD typically, it gives realistic approximations of the order parameters of chiral symmetry breaking (quark condensate etc). In thermal theories the convergence and scale dependence of RGOPT thermodynamical quantities are drastically improved as compared to standard perturbative expansions, and it cures the odd drastic scale dependence observed in other related methods such as the screened perturbation or (resummed) hard-thermal-loop (HTL) perturbation. I will present some recent results in scalar models, and first applications to HTL resummation for QCD thermodynamical quantities, also explaining the additionnal calculations needed in gauge theories with respect to standard HTLpt within our framework.
11:00
Coffee break
Coffee break
11:00 - 11:30
Room: 483A - Malevitch
11:30
Revisiting the lattice pure gauge Landau gauge gluon propagator at zero and finite temperature (45+15)
-
Orlando Oliveira
(
Coimbra University
)
Revisiting the lattice pure gauge Landau gauge gluon propagator at zero and finite temperature (45+15)
Orlando Oliveira
(
Coimbra University
)
11:30 - 12:30
Room: 483A - Malevitch
The computation of the pure gauge Landau gauge gluon propagator is revisited both at zero and finite temperature. For the zero temperature case we discuss the compatibility of the generalised Gribov-Zwanziger predictions and particular attention is given to the computation of the propagator for temperatures near the deconfinement phase transition. Preliminary results for the gluon of the spectral function are also discussed.
12:30
Lunch
Lunch
12:30 - 14:00
Room: 483A - Malevitch
14:00
On QCD correlation functions at finite temperature (50+10)
-
Jan Pawlowski
(
Heidelberg University
)
On QCD correlation functions at finite temperature (50+10)
Jan Pawlowski
(
Heidelberg University
)
14:00 - 15:00
Room: 483A - Malevitch
15:00
The massive Landau-de-Witt gauge at finite temperature and density (45+15)
-
Urko Reinosa
(
Ecole Polytechnique Palaiseau
)
The massive Landau-de-Witt gauge at finite temperature and density (45+15)
Urko Reinosa
(
Ecole Polytechnique Palaiseau
)
15:00 - 16:00
Room: 483A - Malevitch
We review recent results of the massive Landau-de-Witt gauge approach to the description of Yang-Mills and QCD theories at finite temperature and/or densities. In particular we consider the formal but interesting limit of heavy quarks and compare with other approaches, including the lattice as a benchmark. We also discuss some of the limitations of the method and draw some parallels with other approaches.
16:00
Coffee break
Coffee break
16:00 - 16:30
Room: 483A - Malevitch
16:30
Discussion: finite T
Discussion: finite T
16:30 - 18:30
Room: 483A - Malevitch
20:00
Dinner
Dinner
20:00 - 22:00
Room: 483A - Malevitch
Restaurant L'ébauchoir 43-45 rue de Cîteaux, Paris 11 Metro : Faidherbe-Chaligny (line 8)
vendredi 10 novembre 2017
09:00
Poincaré-covariant description of two- and three-body bound states from functional approaches to QFT (45+15)
-
Reinhard Alkofer
(
Graz University
)
Poincaré-covariant description of two- and three-body bound states from functional approaches to QFT (45+15)
Reinhard Alkofer
(
Graz University
)
09:00 - 10:00
Room: 483A - Malevitch
10:00
Coffee break
Coffee break
10:00 - 10:30
Room: 483A - Malevitch
10:30
Small parameters in infrared QCD (45+15)
-
Marcela Peláez
(
Universidad de la República de Montevideo / CPHT-X
)
Small parameters in infrared QCD (45+15)
Marcela Peláez
(
Universidad de la República de Montevideo / CPHT-X
)
10:30 - 11:30
Room: 483A - Malevitch
Lattice simulations show that the running coupling constants obtained through QCD vertices differ in the infrared even though their bare values coincide. For instance, at low momenta the strength of the quark-gluon coupling is about twice the ghost-gluon coupling. None of them diverge in the infrared as it is predicted by standard perturbation theory. Moreover, the ghost-gluon coupling remains moderate even in the infrared. This observation motivates the use of perturbation theory in the ghost-gluon sector in the frame of a massive deformation of QCD Lagrangian in Landau gauge. However, perturbation theory in the quark sector within this massive Lagrangian doesn´t bring as good results as in the pure Yang-Mills case, as should be expected from the larger value of the quark-gluon coupling constant. We propose a controlled systematic expansion in full QCD based in two small parameters: first the Yang.Mills sector couplings and second the inverse of the number of colors (large-Nc limit). The second approximation relies on the fact that the general features of QCD can be observed in the large-Nc limit. This systematic expansion allows us to properly introduce the use of the renormalization group for the rainbow resummation. At leading order, this double expansion leads to the well-known rainbow approximation for the quark propagator whose solution shows spontaneous chiral symmetry breaking for sufficiently large quark-gluon coupling constant.
11:30
Polyakov-loop potentials for the phenomenological investigation of the QCD phase structure (45+15)
-
Rainer Stiele
(
CPHT - Ecole Polytechnique Palaiseau
)
Polyakov-loop potentials for the phenomenological investigation of the QCD phase structure (45+15)
Rainer Stiele
(
CPHT - Ecole Polytechnique Palaiseau
)
11:30 - 12:30
Room: 483A - Malevitch
Polyakov-loop-extended chiral models are useful to get a glimpse on the phase structure of strongly-interacting matter. However, these models rely on simple parameterisations of the Polyakov-loop potential and with present parameter sets different parameterisations give results for pure gauge theory that differ considerably. Of course this introduces even larger uncertainties when the potential is coupled to quarks in Polyakov-loop-extended chiral models. Therefore, it is important to find parameter sets for the different parameterisations such that they agree in their description of latest lattice data on Yang-Mills theory. Furthermore, these parametrised Polyakov-loop potentials miss so far any information on the slope of the potential away from its minimum. But this is the area which determines the expectation value of the Polyakov loop in Polyakov-loop--extended chiral models. Hence, we suggest to include to the existing parameterisations information about the global shape of the Polyakov-loop potential from calculations in nonperturbative, continuum approaches. We show how the existing parametrised Polyakov-loop potentials differ from the calculated ones and which information of the calculated potentials could be included to the parameterisations to increase the predictability of the phase structure of QCD with Polyakov-loop--extended chiral models.
12:30
Lunch
Lunch
12:30 - 14:00
Room: 483A - Malevitch
14:00
Discussion
Discussion
14:00 - 15:30
Room: 483A - Malevitch