Christian Bauer, LBNL

Group Head

Christian Bauer

Email: cwbauer@lbl.gov

Tel:      510-486-7773

Fax:     510-486-6808

Office: 50A-5123

Biography

Christian Bauer received his undergraduate education in Karlsruhe, Germany, and his PhD from the University of Toronto under Michael Luke. After graduating in 2000, he took a postdoc position at UC San Diego. In 2003 he moved to Caltech as a McCone senior research fellow and joined the LBNL theory group in 2005 as a Divisional Fellow to LBNL. Since 2006 he has been Senior Staff Scientist. In 2005 he received an Outstanding Junior Investigator award, and in 2010 an Early Career Award from the Department of Energy. In 2010 he was the recipient of the Presidential Early Career Award.

Research interests

Much of my research in the past has focused on the development of novel calculational techniques to increase our ability to make precise predictions in the standard model.Effective field theories are a wonderful tool to work in realistic situations, where widely separated scales make perturbation theory slowly converging, or where non-perturbative effects become important.

One of my  major accomplishments is the development of Soft-collinear effective theory (SCET), which has been widely used in B physics in the past, and is now applied with great success in the LHC era.

I have been involved in the effort to improve the accuracy of event generators at fixed order. This has led to the development of the GENEVA Monte Carlo. The major difference compared to any other event generators currently on the market or under development, is that GENEVA does not only include higher fixed order accuracy, but higher logarithmic accuracy as well. Many high profile analyses such as H -> WW require jet vetoes to control the backgrounds, and higher logarithmic resummation has been shown to be of crucial importance to reduce theoretical uncertainties to a level comparable with experimental uncertainties. GENEVA will therefore be of vital importance to provide fully exclusive predictions in such restricted regions of phase space.

Resummed results usually require a new separate analytical calculation for each observable under consideration, often within the framework of SCET. Techniques to perform numerical resummations have been available for a while using traditional resummation techniques. Together with Pier Monni I have developed a numerical resummation technique based on SCET which is systematically improvable order by order.

Recently I have started to work on the rapidly growing field of Quantum Computing (QC), with an eye towards applications of QC to High Energy Physics, and making currently available Noisy Intermediate Scale Quantum (NISQ) devices more reliable. We have developed quantum algorithms for parton showers, which can include certain quantum interference that are exponentially difficult to include with many showers. We have also devised several methods for the mitigation of gate and readout errors.

Selected publications

(Full list of publications can be found here.)

Dark Matter Spectra from the Electroweak to the Planck Scale,
with N. L. Rodd and B. R. Webber, [arXiv:2007.15001]

Zero-noise extrapolation for quantum-gate error mitigation with identity insertions,
with A. He, B. Nachman, W. A. de Jong, PRA 102 (2020) 1, 012426, [arXiv:2003.04941]

Unfolding Quantum Computer Readout Noise,
with B. Nachman, M. Urbanek, W. A. de Jong, [arXiv:1910.01969]

A quantum algorithm for high energy physics simulations,
with W. A. de Jong, B. Nachman, D. Provasoli, [arXiv:1904.03196]

A numerical formulation of resummation in effective field theory,
with P. F. Monni, arXiv:2007.04320]

Standard Model Parton Distributions at Very High Energies,
with N. Ferland and B. R. Webber, JHEP 1708 (2017) 036, [arXiv:1703.08562]

Drell-Yan Production at NNLL’+NNLO Matched to Parton Showers,
with S. Alioli, C. Berggren, F. J. Tackmann, J. R. Walsh, PRD 92, 094020 [arXiv:1508.01475]

Factorization and Resummation for Dijet Invariant Mass Spectra ,
with F. J. Tackmann, J. R. Walsh, S. Zuberi, PRD 85, 074006, [arXiv:1106.6047]

Factorization of e+e- Event shape distributions with Hadronic Final States in SCET
with S. P. Fleming, C. Lee, G. F. Sterman, PRD 78, 034027, [arXiv:hep-ph/0801.4569]

Event Generation from Effective Field Theory,
with M. D. Schwartz, PRD 76, 074004 [arXiv:hep-ph/0607296].

Soft collinear factorization in effective field theory,
with D. Pirjol, I. W. Stewart, PRD 65, 054022, [arXiv:hep-ph/0109045].

An effective theory for collinear and soft gluons: Heavy to light decays,
with S. Fleming, D. Pirjol, I. W. Stewart, PLB 516 (2001) 134-142, [arXiv:hep-ph/0011336].

Summing Sudakov logarithms in B->Xs γ in effective field theory,
with S. Fleming, M. E. Luke, PRD 63 (2000) 014006, [arXiv:hep-ph/0005275].