Interview with Daniela Saadeh: winner of the IOP Gravitational Physics Group (GPG) thesis prize

Daniela Saadeh

Daniela Saadeh – UCL Astrophysics Group

CQG is proud to sponsor the IOP Gravitational Physics Group (GPG) thesis prize. This year the prize was awarded to Daniela Saadeh, who we have interviewed below. Congratulations Daniela!

Can you tell us a little bit about the work in your thesis?

A fundamental assumption of the standard model of cosmology is that the large-scale Universe is isotropic – i.e. that its properties are independent of direction. Historically, this concept stemmed from the Copernican Principle, the philosophical statement that we do not occupy a ‘special’ place in the Universe. In physical terms, this idea is converted into the assumption that all positions and directions in the Universe are equivalent, so that no observer is ‘privileged’.

However, assumptions must be tested, especially foundational ones. General relativity – our standard theory of gravity – allows for many ways in which spacetime could be anisotropic: directional symmetry is not fundamentally required. If the Universe were indeed to be anisotropic, we would actually need to carefully revise our understanding (for instance, calculations about its history or content). Making this health check is very important! Continue reading

So long, and thanks for all the manuscripts

Adam Day

Adam Day is the Publisher of Classical and Quantum Gravity

Years ago, I sat, somewhat nervously, in a small, dimly lit room in an old office block. I’d applied for a dream job and I was expecting to learn the outcome of that application. A senior member of staff tactfully began the meeting with some friendly small-talk that did absolutely nothing to calm my nerves.

I’d heard of CQG – even before I’d seen the job advert. Reputed for its high standards of peer-review, it also held the distinction of being the first physics journal on the web. Clearly, this was a journal for brilliant pioneers and innovators (submit here) and I wanted to be part of that. Furthermore, I’d enjoyed studying relativity as an undergraduate and had hoped to become a gravitational-wave researcher, so the science of CQG was already close to my heart.  I can’t even remember the colour of the walls in that old office, but I can still hear the words “I’d like to offer you the job” very clearly.

Looking back Continue reading

Highlights of 2016 now free to read 

By Clifford Will.

Clifford Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity, Distinguished Professor of Physics at the University of Florida, Chercheur Associé at the Institut d’Astrophysique de Paris, and James McDonnell Professor of Space Sciences Emeritus at Washington University in St. Louis.

I am delighted to present the CQG Highlights of 2016 which are now free to read.  This prestigious annual collection is selected by the editorial board and includes notable papers on gravitational waves, black holes, general relativity, cosmology, quantum gravity and more.

As well as being free to read on the web, each paper is promoted by the journal in a number of campaigns.  Watch for the CQG Highlights brochure at your next conference.

CQG Highlights remains one of CQG’s most popular promotions.  Don’t miss your chance to be included in CQG Highlights of 2017 by publishing your next great paper in CQG.



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Happy new year!

By Clifford Will.

Clifford Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity, Distinguished Professor of Physics at the University of Florida, Chercheur Associé at the Institut d’Astrophysique de Paris, and James McDonnell Professor of Space Sciences Emeritus at Washington University in St. Louis.

What a year for gravitational physics!  In February, the LIGO and Virgo Collaborations (LVC) announced the first detection of gravitational waves.  The MICROSCOPE satellite test of the equivalence principle took to the skies in April and, in June, LISA Pathfinder surpassed all expectations in demonstrating the key technologies required to detect gravitational waves in space.  As if all that wasn’t enough, the LVC announced a second detection of a binary black hole merger later that month.  By September, NASA revealed that it would rejoin ESA in funding the LISA mission with a view to launching a 3-armed space interferometer by 2030.  Could we have wished for more?

CQG launched a focus issue on the topic of gravitational waves in 2016 edited by Peter Shawhan and Deirdre Shoemaker.  You can submit your next great paper on gravitational waves to the issue which is currently open to submissions and will be promoted in a number of channels throughout 2017.  All submissions will be subject to CQG’s usual high standard of peer review.

To keep track of the latest CQG publications and news in 2017, you can follow the CQG+ blog or follow the journal on social media (Twitter, Facebook).

I want to express my appreciation to all CQG authors, referees and readers who supported the journal in 2016.  I particularly wish to thank the journal’s Editorial Board Members and Advisory Panel Members who assist in directing the strategy of the journal and who oversee CQG’s peer review.  I also welcome new Board and Panel members to CQG. I look forward to working with all of you in the coming year.

With the LIGO detectors’ second observation run underway, I am certain that we have more to look forward to in 2017. Continue reading

LIGO’s gravitational wave detection is Physics World 2016 Breakthrough of the Year

by Clifford M Will.

Physics World breakthrough of the year prize

The Physics World 2016 Breakthrough of the Year goes to the LIGO Scientific Collaboration for their revolutionary, first ever direct observations of gravitational waves.

Long awaited direct detection of Einstein’s gravitational-waves tops Physics World’s list of the 10 key breakthroughs in physics in 2016

It give me great pleasure to report that the LIGO Scientific Collaboration are to receive Physics World’s Breakthrough of the year award.  At the end of every year, the Physics World editorial team reveals what it believes to be the top 10 research breakthroughs for the past year and one of these is selected to be the Physics World Breakthrough of the year.

In recognition of this achievement, the Physics World team have created a short documentary movie with the assistance of members of the LIGO collaboration from Cardiff University.

The video features Samantha Usman, who recently wrote an excellent CQG+ entry about the discovery.
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Highlights of 2015

Clifford Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity

The latest CQG Highlights are now available to view.  These papers represent the most interesting and important work published in CQG in 2015.  They were selected by the CQG Editorial Board and approved at CQG’s recent annual board meeting in London.

This year marks a break from the process used in past years.  CQG Highlights used to be Continue reading

The world we live in – #GR21

This is the second in a series of posts timed to coincide with the GR21 meeting. Keep an eye on CQG+ this week, for more posts on gravitational waves, the CQG Highlights and more.

Adam Day and the NYT building

Adam Day admiring the view from the top of the Rockefeller Center in NYC

I once had the experience of trying to find journal articles in an old bricks and mortar library. I spent a whole afternoon scouring a few thousand journal copies (and never did find what I was looking for). Information was scarce in those days and there were few ways to get it.

Watching scholarly communication develop since then has been interesting. In many ways, it’s now much easier to find papers – especially when you know exactly what you want to read. However, readers increasingly now find Continue reading

What makes a CQG Paper different?

Adam Day

Adam Day is the Executive Editor of Classical and Quantum Gravity

CQG is known for its high standard of peer review. We’re extremely grateful to everyone in the gravitational physics community who has helped to build and maintain this standard over the years. Detailing everything that goes into this would go beyond the scope of a single blog post. Nevertheless, I thought it might be helpful to you if I say a few words about what we are looking for in referees’ reports here at the CQG editorial office.

If you have refereed for CQG lately, you will have seen Continue reading

2016 Bergmann-Wheeler Thesis Prize winner: Lisa Glaser

Lisa Glaser

Lisa Glaser is currently a Research Fellow at University of Nottingham, and will (from September 2016) join Renate Loll’s group at the Radboud Universitet in Nijmegen with a Marie Skłodowska-Curie fellowship to explore renormalisation in discrete theories of quantum gravity.
You can follow her on Twitter. 

1. Tell us about your thesis

During my Ph.D. I worked on causal dynamical triangulations and causal set theory. While these approaches are very different at first sight, upon closer examination they show important similarities. In both theories we try to solve the path integral over geometries by introducing a regularisation.

In causal dynamical triangulations the regularisation are simplices, which scale away in the continuum limit, while causal set theory proposes a fundamental smallest volume of space-time events. Another similarity is that both of these theories try to incorporate the Lorentzian structure of space-time into the theory. In causal dynamical triangulations this is implemented through a Continue reading

Gravitational waves detected. Einstein was right … again

Clifford Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity

As if celebrating the 100th birthday of general relativity weren’t enough, the LIGO-Virgo collaboration has provided “the icing on the cake” with today’s announcement of the first direct detection of gravitational waves. At press conferences in the USA and Europe, and in a paper in Physical Review Letters published afterward, the team announced the detection of a signal from a system of two merging black holes.

The signal arrived on 14 September, 2015 (its official designation is GW150914), and was detected by both the Hanford and Livingston advanced detectors of the LIGO observatory (the advanced Virgo instrument in Italy is not yet online). It was detected first by Continue reading