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Celestial Sphere: holography, CFT and amplitudes (Higgs Centre Workshop)

Event description

This workshop will explore and establish connections between flat space holography, conformal field theory and scattering amplitudes. Newly discovered structures relating these three areas have arisen in the context of the 'celestial sphere,' the space of generators for the null conformal boundary of an asymptotically flat space-time. It is hoped that by bringing together experts from these fields, the existence and properties of 'celestial' conformal field theories can be better understood, with a view to applying, testing and generalizing techniques from scattering amplitudes and conformal field theory.

Specific topics to be discussed include:

  • scattering amplitudes in the conformal primary basis
  • conformal soft theorems

  • celestial OPEs

  • conformal bootstrap, positivity and celestial amplitudes

  • asymptotic symmetries

COVID Update:

Due to ongoing uncertainty regarding the state of international travel, this workshop will be held as a hybrid virtual/in-person event, with all talks available via Zoom. Participants will have the option to indicate if they wish to apply for in-person attendance when registering. The number of in-person attendees will be capped in accordance with health & safety guidance, and will be chosen by the organizers.

Invited Speakers

  • Glenn Barnich (ULB)

  • Eduardo Casali (UC Davis)

  • Laura Donnay (TU Vienna)

  • Jelle Hartong (Edinburgh)

  • Lorenzo Magnea (Torino)

  • Lionel Mason (Oxford)

  • Sabrina Pasterski (Princeton)

  • Guilherme Pimentel (Leiden)

  • Andrea Puhm (Ecole Polytechnique)

  • Ana-Maria Raclariu (Perimeter Institute)

  • Atul Sharma (Oxford)

  • Akshay Yelleshpur Srikant (Brown)

  • Stephan Stieberger (MPI Munich)

  • Andrew Strominger (Harvard)


  • Tim Adamo (Edinburgh)

  • Monica Pate (Harvard)

  • Joan Simon (Edinburgh)

  • Tomasz Taylor (Northeastern)


    Support for this workshop is provided by the Higgs Centre for Theoretical Physics and the Edinburgh Mathematical Society


See the full timetable on Indico

13 Sep / 08:15—08:30
Welcome (0h15′)
13 Sep / 08:30—09:30
Laura Donnay (TU Vienna) - BMS flux algebra in celestial holography (1h00′)
13 Sep / 10:00—11:00
Stephan Stieberger (MPI Munich) - Celestial Gluon Amplitudes: Single-valued Correlators and Conformal Blocks (1h00′)
13 Sep / 12:30—13:30
Lionel Mason (Oxford) - On the twistor origin of celestial W-infinity symmetry (1h00′)
  • Mason, Lionel (Oxford University)
13 Sep / 14:00—15:00
Andrew Strominger (Harvard) - w infinty and the celestial sphere (1h00′)
13 Sep / 15:00—16:00
Ana-Maria Raclariu (Perimeter Institute - Shadow momenta and new constraints on celestial amplitudes (1h00′)
14 Sep / 08:30—09:30
Jelle Hartong (Edinburgh) - Carroll: to run or to stand still (1h00′)
14 Sep / 10:00—11:00
Andrea Puhm (Ecole Polytechnique) - From diamonds to pyramids on the celestial sphere (1h00′)
14 Sep / 12:30—13:30
Guilherme Pimentel (Leiden) - Invitation to cosmological correlators (1h00′)
14 Sep / 14:00—15:00
Eduardo Casali (UC Davis) - Twistor strings and the Celestial OPE (1h00′)
14 Sep / 15:30—16:30
Higgs Centre Colloquium (1h00′)
15 Sep / 08:30—09:30
Atul Sharma (Oxford) - Twistors, light transforms, and the celestial Grassmannian (1h00′)
15 Sep / 10:00—11:00
Glenn Barnich (ULB) - Photons & gravitons in a Casimir box (1h00′)
15 Sep / 12:30—13:30
Lorenzo Magnea (Torino) - Non-abelian infrared divergences on the celestial sphere (1h00′)
15 Sep / 14:00—15:00
Sabrina Pasterski (Princeton) - Fun with Celestial Dressings: Harbingers of Chaos, Heralds of Symmetry (1h00′)
15 Sep / 15:00—16:00
Akshay Yelleshpur Srikant (Brown) - Celestial MHV amplitudes: polytopes, singularities and differential equations (1h00′)

Celestial Sphere: holography, CFT and amplitudes (Higgs Centre Workshop)


Higgs Centre Seminar Room, JCMB (Find us on campus maps)
The Higgs Centre for Theoretical Physics
School of Physics and Astronomy
James Clerk Maxwell Building, 4305
Peter Guthrie Tait Road


  • Tim Adamo
    • University of Edinburgh
    • School of Mathematics (Mathematical Physics Group)
  • Monica Pate
    • Harvard University
  • Joan Simon
    • University of Edinburgh
  • Tomasz Taylor
    • Northeastern University