Dr Ricardo Monteiro
Royal Society University Research Fellow
Email: ricardo.monteiro@qmul.ac.uk
Telephone: 0207 882 7813
Room Number: G. O. Jones Building, Room 225
Profile
I joined the Centre for Research in String Theory in 2017. Previously, I held research positions at CERN, at the Mathematical Institute in Oxford, and at the Niels Bohr Institute in Copenhagen. I did my graduate studies at DAMTP in Cambridge, and my undergraduate studies at IST in Lisbon.
Teaching
I currently teach the 3rdyear course Spacetime and Gravity. The course is a basic introduction to Einstein's theory of general relativity.
I also supervise undergraduate and master projects.
Research
Research Interests:
I have a broad interest in highenergy theoretical physics. My recent work focuses on perturbative aspects of quantum field theory, quantum gravity and string theory.
One of my main areas of activity has been the perturbative description of gravity as a double copy of gauge theory. This idea appeared in the study of scattering amplitudes, which are notoriously complicated in theories of gravity if traditional methods are used. The doublecopy technique allows us to perform certain gravity computations using much simpler computations in gauge theory. My goals here are twofold: to investigate the mathematical structure behind the double copy, including at loop level (quantum effects), and to apply this technique to a wider set of problems, including the study of classical solutions (perturbative or exact) in gravity theories.
My other major line of work is the description of certain quantum field theories in terms of worldsheet models inspired by string theory, known as ambitwistor strings. These models underlie a new mathematical formalism for the scattering amplitudes of massless particles, based on scattering equations that relate the kinematic invariants to the moduli space of a sphere. My main focus here has been the extension of this very promising formalism to loop level, which opens the possibility of a much wider application. Both gauge theory and gravity admit this type of formalism, and this is also a promising avenue to understand the doublecopy relation at a more fundamental level.
Apart from these topics, I maintain my interest for areas in which I have worked in the past. These include black holes in general relativity and in string theory, and the AdS/CFT correspondence between a theory of gravity (string theory) and a lowerdimensional (conformal) field theory.
Funding
Grants held at QMUL:
Royal Society University Research Fellowship, 2017  2021 (£452,148)
Royal Society Grant supporting a PhD Studentship, 2017  2021 (£85,492)
Royal Society Grant supporting a PhD Studentship, 2018  2022 (£85,992)
Publications
You can see a list of my publications at INSPIREHEP.

Monteiro R, Nicholson I, O¿Connell D (2019). Spinorhelicity and the algebraic classification of higherdimensional spacetimes. nameOfConference
Citations: 0 
Luna A, MONTEIRO RJF, Nicholson I et al. (2019). Type D spacetimes and the Weyl double copy. nameOfConference
Citations: 0 
Geyer Y, Monteiro R (2018). Twoloop scattering amplitudes from ambitwistor strings: from genus two to the nodal Riemann sphere. nameOfConference
Citations: 0 
Geyer Y, Monteiro R (2018). Gluons and gravitons at one loop from ambitwistor strings. nameOfConference
Citations: 0 
Adamo T, Monteiro R, Paulos MF (2017). Spacetime CFTs from the Riemann sphere. nameOfConference
Citations: 0 
Geyer Y, Mason L, Monteiro R et al. (2016). Twoloop scattering amplitudes from the Riemann sphere. nameOfConference
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Geyer Y, Mason L, Monteiro R et al. (2016). Oneloop amplitudes on the Riemann sphere. nameOfConference
QMRO: qmroHref
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He S, Monteiro R, Schlotterer O (2016). Stringinspired BCJ numerators for oneloop MHV amplitudes. nameOfConference
QMRO: qmroHref
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Casali E, Geyer Y, Mason L et al. (2015). New ambitwistor string theories. nameOfConference
QMRO: qmroHref
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Luna A, Monteiro R, O'Connell D et al. (2015). The classical double copy for Taub–NUT spacetime. nameOfConference
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Geyer Y, Mason L, Monteiro R et al. (publicationYear). Loop Integrands for Scattering Amplitudes from the Riemann Sphere. nameOfConference
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Monteiro R, O'Connell D, White CD (2015). Gravity as a double copy of gauge theory: from amplitudes to black holes. nameOfConference
QMRO: qmroHref
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Monteiro R, O¿Connell D, White CD (2014). Black holes and the double copy. nameOfConference
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Monteiro R, O¿Connell D (2014). The kinematic algebras from the scattering equations. nameOfConference
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BjerrumBohr NEJ, Dennen T, Monteiro R et al. (2013). Integrand oxidation and oneloop colourdual numerators in $ \mathcal{N}=4 $ gauge theory. nameOfConference
QMRO: qmroHref
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Gath J, Hartong J, Monteiro R et al. (2013). Holographic models for theories with hyperscaling violation. nameOfConference
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Boels RH, Isermann RS, Monteiro R et al. (2013). ColourKinematics duality for oneloop rational amplitudes. nameOfConference
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Dias ÓJC, Figueras P, Minwalla S et al. (2012). Hairy black holes and solitons in global AdS5. nameOfConference
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BjerrumBohr NEJ, Damgaard PH, Monteiro R et al. (2012). Algebras for amplitudes. nameOfConference
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Dias ÓJC, Monteiro R, Santos JE (2011). Ultraspinning instability: the missing link. nameOfConference
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Monteiro R, O¿Connell D (2011). The kinematic algebra from the selfdual sector. nameOfConference
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Caldarelli MM, Dias ÓJC, Monteiro R et al. (2011). Black funnels and droplets in thermal equilibrium. nameOfConference
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Dias ÓJC, Figueras P, Monteiro R et al. (2010). Ultraspinning instability of antide Sitter black holes. nameOfConference
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Costa MS, Monteiro R, Santos JE et al. (2010). On threepoint correlation functions in the gauge/gravity duality. nameOfConference
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Dias ÓJC, Figueras P, Monteiro R et al. (publicationYear). Ultraspinning instability of rotating black holes. nameOfConference
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Dias ÓJC, Monteiro R, Reall HS et al. (2010). A scalar field condensation instability of rotating Antide Sitter black holes. nameOfConference
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Dias ÓJC, Figueras P, Monteiro R et al. (2010). An instability of higherdimensional rotating black holes. nameOfConference
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Monteiro R, Perry MJ, Santos JE (publicationYear). Semiclassical instabilities of Kerrantide Sitter black holes. nameOfConference
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Dias ÓJC, Figueras P, Monteiro R et al. (publicationYear). Instability and new phases of higherdimensional rotating black holes. nameOfConference
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Monteiro R, Perry MJ, Santos JE (publicationYear). Thermodynamic instability of rotating black holes. nameOfConference
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Monteiro R, Santos JE (publicationYear). Negative modes and the thermodynamics of ReissnerNordström black holes. nameOfConference
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Bertolami O, Monteiro R (publicationYear). Varying electromagnetic coupling and primordial magnetic fields. nameOfConference
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Supervision
Scattering Amplitudes and Ambitwistor Strings
This project focuses on a new approach to describe quantum field theory, and in particular to calculate scattering amplitudes, which is inspired by string theory. A new and intriguing breed of “stringlike” theories, known as ambitwistor strings, is actually a class of wellknown particle theories in disguise, including gravity and gauge theory. While these theories are formulated as twodimensional conformal field theories, similarly to string theory, they do not possess the infinite tower of massive states that characterises string theory, but possess only a massless spectrum perturbatively. My recent research has opened the way to make these theories a serious tool to calculate scattering amplitudes at loop level in theories of physical interest.
The major goal of the project will be to understand the nature and the applicability of ambitwistor strings. There are plenty of questions. How does the allloop expansion work? What is the most general class of theories that these models can describe? How can we make the calculations more efficient? Beyond scattering amplitudes, what other quantities can we calculate? Can they bring a new light into the connections between theories, such as those between gauge theory and gravity? And how does standard string theory fit into this picture?
Requirements: knowledge of Quantum Field Theory, General Relativity and String Theory at the level of a Master course.
Gravity as a Double Copy of Gauge Theory
This project explores a powerful connection between gauge theory and gravity, two fundamental ingredients in our understanding of Nature. It is clear that there is a close mathematical analogy between the two theories, with gauge theory describing "spin1" particles and gravity describing "spin2" particles. In recent years, that relationship has been shown to be much closer than previously recognised. It turns out that gravity can be expressed as a "double copy" of gauge theory, at least perturbatively. Using this technique, fiendish calculations in gravity can be substituted by much simpler calculations in gauge theory. One of the applications of the technique is to study in detail the ultraviolet divergences in a variety of theories of gravity, a problem at the heart of quantum gravity. More recently, there is a new programme to study classical solutions (either perturbative or exact) in general relativity using the double copy.
The aims of the project are (1) to understand at a more fundamental level the mathematical structure behind the doublecopy relation, (2) to develop an efficient formalism for looplevel amplitudes, (3) to investigate the connection between the spaces of solutions to the Einstein equations and to the YangMills equations, and (4) to explore the application of the double copy in gravitational phenomenology, namely to problems of astrophysical interest involving gravitational waves.
Requirements: knowledge of Quantum Field Theory and General Relativity at the level of a Master course.
Public Engagement
I have some outreach experience, both as a scientist and as an organiser, including Pint of Science (UK), Folkeuniversitetet (Denmark), Associacao Juvenil de Ciencia and Ciencia Viva (Portugal). I am also involved in the outreach activities of the researcher training network SAGEX.
The most common type of outreach for my scientific area is a public talk, but I am also open to other suggestions.