Course
19S1 D. Anselmi
Theories of gravitation
Program
Recent Papers

22A2 Damiano Anselmi
Fakeons versus LeeWick ghosts: physical PauliVillars fields, finite QED and quantum gravityWe reconsider the LeeWick (LW) models and compare their properties to the properties of the models that contain purely virtual particles. We argue against the ... (read more)

22A1 Damiano Anselmi
Dressed propagators, fakeon selfenergy and peak uncertaintyWe study the resummation of selfenergy diagrams into dressed propagators in the case of purely virtual particles and compare the results with those obtained for ... (read more)

21A5 Damiano Anselmi
Diagrammar of physical and fake particles and spectral optical theoremWe prove spectral optical identities in quantum field theories of physical particles (defined by the Feynman $i\epsilon $ prescription) and purely virtual particles (defined by ... (read more)

21A4 Damiano Anselmi, Kristjan Kannike, Carlo Marzo, Luca Marzola, Aurora Melis, Kristjan Müürsepp, Marco Piva and Martti Raidal
A fake doublet solution to the muon anomalous magnetic momentExtensions to the Standard Model that use strictly offshell degrees of freedom – the fakeons – allow for new measurable interactions at energy scales usually ... (read more)

21A3 Damiano Anselmi, Kristjan Kannike, Carlo Marzo, Luca Marzola, Aurora Melis, Kristjan Müürsepp, Marco Piva, Martti Raidal
Phenomenology of a Fake Inert Doublet ModelWe introduce a new way of modeling the physics beyond the Standard Model by considering fake, strictly offshell degrees of freedom: the fakeons. To demonstrate ... (read more)

21A2 Damiano Anselmi
Perturbation spectra and renormalizationgroup techniques in doublefield inflation and quantum gravity cosmologyWe study primordial cosmology with two scalar fields that participate in inflation at the same time, by coupling quantum gravity (i.e., the theory $R+R^2+C^2$ with ... (read more)

21A1 Damiano Anselmi, Filippo Fruzza and Marco Piva
Renormalizationgroup techniques for singlefield inflation in primordial cosmology and quantum gravityWe study inflation as a “cosmic” renormalizationgroup flow. The flow, which encodes the dependence on the background metric, is described by a running coupling $\alpha ... (read more)

20A5 Damiano Anselmi
Highorder corrections to inflationary perturbation spectra in quantum gravityWe compute the inflationary perturbation spectra and the quantity $r+8n_{T}$ to the nexttonexttoleading log order in quantum gravity with purely virtual particles (which means the ... (read more)

20A4 Damiano Anselmi
Cosmic inflation as a renormalizationgroup flow: the running of power spectra in quantum gravityWe study the running of power spectra in inflationary cosmology as a renormalizationgroup flow from the de Sitter fixed point. The beta function is provided ... (read more)

20A3 Damiano Anselmi
Quantum field theories of arbitraryspin massive multiplets and Palatini quantum gravityWe formulate quantum field theories of massive fields of arbitrary spins. The presence of both physical and fake particles, organized into multiplets, makes it possible ... (read more)

20A2 Damiano Anselmi, Eugenio Bianchi and Marco Piva
Predictions of quantum gravity in inflationary cosmology: effects of the Weylsquared termWe derive the predictions of quantum gravity with fakeons on the amplitudes and spectral indices of the scalar and tensor fluctuations in inflationary cosmology. The ... (read more)

20A1 Damiano Anselmi
The quest for purely virtual quanta: fakeons versus FeynmanWheeler particlesThe search for purely virtual quanta has attracted interest in the past. We consider various proposals and compare them to the concept of fake particle, ... (read more)

19A3 Damiano Anselmi and Antonio Marino
Fakeons and microcausality: light cones, gravitational waves and the Hubble constantThe concept of fake particle, or “fakeon”, allows us to make sense of quantum gravity as an ultraviolet complete theory, by renouncing causality at very ... (read more)

19A2 Damiano Anselmi
Fakeons, unitarity, massive gravitons and the cosmological constantWe give a simple proof of perturbative unitarity in gauge theories and quantum gravity using a special gauge that allows us to separate the physical ... (read more)

19A1 Damiano Anselmi
Fakeons and the classicization of quantum gravity: the FLRW metricUnder certain assumptions, it is possible to make sense of higher derivative theories by quantizing the unwanted degrees of freedom as fakeons, which are later ... (read more)
Archive for November 2015
Using the background field method and the BatalinVilkovisky formalism, we prove a key theorem on the cohomology of perturbatively local functionals of arbitrary ghost numbers, in renormalizable and nonrenormalizable quantum field theories whose gauge symmetries are general covariance, local Lorentz symmetry, nonAbelian YangMills symmetries and Abelian gauge symmetries. Interpolating between the background field approach and the usual, nonbackground approach by means of a canonical transformation, we take advantage of the properties of both approaches and prove that a closed functional is the sum of an exact functional plus a functional that depends only on the physical fields and possibly the ghosts. The assumptions of the theorem are the mathematical versions of general properties that characterize the counterterms and the local contributions to the potential anomalies. This makes the outcome a theorem on the cohomology of renormalization, rather than the whole local cohomology. The result supersedes numerous involved arguments that are available in the literature.
Phys. Rev. D 93 (2016) 065034  DOI: 10.1103/PhysRevD.93.065034
15A3 Damiano Anselmi
Some reference formulas for the generating functions of canonical transformations
We study some properties of the canonical transformations in classical mechanics and quantum field theory and give a number of practical formulas concerning their generating functions. First, we give a diagrammatic formula for the perturbative expansion of the composition law around the identity map. Then, we propose a standard way to express the generating function of a canonical transformation by means of a certain “componential” map, which obeys the BakerCampbellHausdorff formula. We derive the diagrammatic interpretation of the componential map, work out its relation with the solution of the HamiltonJacobi equation and derive its timeordered version. Finally, we generalize the results to the BatalinVilkovisky formalism, where the conjugate variables may have both bosonic and fermionic statistics, and describe applications to quantum field theory.
Eur. Phys. J. C 76 (2016) 49  DOI: 10.1140/epjc/s100520153874y
Search this site
Book
14B1 D. Anselmi
Renormalization
Course on renormalization, taught in Pisa in 2015. (More chapters will be added later.)
Last update: May 9th 2015, 230 pages
Avaibable on Amazon:
Contents:
Preface
1. Functional integral
2. Renormalization
3. Renormalization group
4. Gauge symmetry
5. Canonical formalism
6. Quantum electrodynamics
7. NonAbelian gauge field theories
Notation and useful formulas
References
Sections
 Cosmology (13)
 Phenomenology beyond SM (5)
 Quantum gravity (54)
 Standard model (10)
 AdlerBardeen theorem (5)
 Background field method (3)
 Unitarity of quantum field theory (22)
 Fakeons (41)
 Renormalization of general gauge theories (14)
 Fieldcovariant quantum field theory (4)
 Lorentz violating quantum field theory (11)
 Renormalization group (14)
 Infinite reduction of couplings (5)
 Regularization (5)
 Conformal field theory (20)
 Topological field theory (5)
 Instantons (4)
 Field redefinitions (4)
 Dimensional regularization (5)
 Philosophy of science (7)
 Biophysics (3)
 Videos (20)
Most used tags
Logo
Cite papers of this site as follows:
Auths, Title, 'year'A'num' Renorm
For example:
D. Anselmi, Master functional and proper formalism for quantum gauge field theory, 12A3 Renorm
Cite books as
Auths, Title, 'year'B'num' Renorm
Cite reviews as
Auths, Title, 'year'R'num' Renorm
Cite proceedings as
Auths, Title, 'year'P'num' Renorm
Cite theorems as
Auths, Title, Theorem 'year'T'num' Renorm
Cite exercises as
Auths, Title, Exercise 'year'E'num' Renorm
You may also want to add links as shown
Search documents
Archive
 April 2022
 March 2022
 February 2022
 January 2022
 September 2021
 May 2021
 March 2021
 December 2020
 November 2020
 October 2020
 July 2020
 June 2020
 May 2020
 January 2020
 December 2019
 November 2019
 October 2019
 September 2019
 June 2019
 May 2019
 April 2019
 March 2019
 January 2019
 November 2018
 October 2018
 September 2018
 June 2018
 March 2018
 January 2018
 April 2017
 March 2017
 January 2017
 December 2016
 June 2016
 November 2015
 January 2015
 August 2014
 May 2014
 February 2014
 November 2013
 May 2013
 March 2013
 January 2013
 September 2012
 May 2012
 January 2011
 February 2010
 December 2009
 April 2009
 August 2008
 July 2007
 April 2007
 November 2006
 May 2006
 September 2005
 March 2005
 February 2005
 April 2004
 September 2003
 December 2002
 October 2002
 May 2002
 October 2001
 July 2001
 January 2001
 May 2000
 December 1999
 November 1999
 August 1999
 June 1999
 May 1999
 March 1999
 November 1998
 September 1998
 August 1998
 February 1997
 July 1996
 July 1995
 April 1995
 November 1994
 July 1994
 September 1993
 July 1993