Visit to Shangai

Many things have happened in the last few weeks, including the Centenary of General Relativity. On November 25th, I wanted to write a post on this event, but I couldn't because I was visiting Cosimo Bambi's gravity group at Fudan University in Shangai and, as it is infamously known, Google products (including this webpage) are inaccessible from China. None of the standard workaround really worked for me so, as a part of my Chinese trip, I have experienced how one feels being without access to gmail, google maps, facebook, etc... (it turned out to be not that bad in fact..)

During the visit, we had a mini-workshop with astrophysicists Javier Garcia-Martinez (Harvard-Smithsonian CfA), Thomas Dauser (Erlangen-Nuremberg) and Matt Middleton (Cambridge) who are working on different aspects of the electromagnetic emission from accretion disks as a possible way to measure the black-hole spin.

Shangai's skyline as viewed from one of the skyscrapers of Fudan University. The city is simply ENORMOUS..

Recommended by us: Einstein's Special Theory of Relativity postulates explained by a teenager

""
Eighteen-year-old student Ryan Chester has just won US$400,000 for this video explaining Einstein’s Special Theory of Relativity as part of the inaugural Breakthrough Junior Challenge - an international competition that aims to inspire the next generation of scientists and science communicators. And it’s not hard to see why. If you heard the words, "Einstein’s Special Theory of--" and tuned out because it’s all too hard, we have a feeling Ryan will change your mind.

 Original Sciencealert article here

""

TAUP 2015 or On my first international conference

Mr. What and Mr. Why

Topics in Astroparticle and Underground Physics (TAUP), is an international biennal conference arrived at its XIV edition. It covers topics from cosmology and particle physics, to trans dark matter and neutrino physics and to continue with high energy astrophysics, cosmic rays and gravitational waves. Theoretical perspectives as well as experimental strategies and developments are included.

TAUP is born at the Laboratori Nazionali del Gran Sasso (LNGS) of the Istituto Nazionale di Fisica Nucleare (INFN) and we are equal in
age, besides that, because of the biennal frequency, it is a sparkling teenager. About me, well...  I am already a PhD student and I have attended the conference with a nice group of colleagues.

Visit to EGO-VIRGO

A meeting of the theoretical and experimental groups of the Italian Institute for Nuclear Physics (INFN) working on the detection of gravitational waves and on theoretical aspects related to them was held at the European Gravitational Observatory (EGO) in Cascina, near Pisa.

The site hosts Virgo, a detector of gravitational waves which -in one year from now- will be ready to join its U.S. cousin Ligo in the decade-long search of gravitational waves from compact objects.

Me standing in front of one of the 3-km long arms of Virgo. Is the motion due to the passage of a gravitational wave? Hope not since the detector is still offline...

What is a gravitational wave?

Summer Reading

Last year was "Fifty shades of Grey". This summer --no matter if you are sunbathing, hiking or enjoying desolated cities-- if you start pondering about black holes, superradiance, and related subjects, we got you covered:

The book will be soon available on the Springer webpage and on Amazon. Hurry up to buy a copy containing the typo in Vitor's name before they fix it. Those copies will be priceless hundred years from now :)

The book will be available in August but can be already pre-ordered. It costs $60 in the U.S. and about 45 Euros in Europe and the authors get about the 10% of the profit. This means that each of the authors (Richard, "Victor" and I) will get about 3 Euros for each sold copy. Taking "50 shades of Grey" as a reference, a back-of-the-envelope estimate suggests we might become rich in ~10^9 years.

CQG+ article on "Black-hole superradiance and the hunt for dark matter"

Our recent paper on black-hole superradiance has been highlighted in the journal Classical and Quantum Gravity, which contains a CQG+ Section where the authors of highlighted papers are asked to write informally about their work. You can find our contribution here:

http://cqgplus.com/2015/06/11/black-hole-superradiance-and-the-hunt-for-dark-matter/

Monte Carlo simulation of the end-state of the superradiant instability in the so-called “Regge plane”. Each point represents the final black-hole mass and spin after the superradiant evolution. As a result of the instability, old black holes do not populate the region above the green threshold curve, leaving a “hole” in the Regge plane as predicted by a linearized analysis. The experimental points with error bars refer to observed supermassive black holes. The three panels refer to different gas accretion rates.

Enjoy the reading!

Workshop + Conference @ The Fields Institute

"The year of the 100th anniversary of the formulation of Einstein's General Relativity will be remembered as the least productive one for the general-relativity community."

This is what I've heard more than once during the time spent at The Fields Institute in Toronto these weeks :-)
The Institute is organizing a long Focus Program to celebrate the centenary of one of Einstein's greatest achievements, the formulation of a relativistic theory of gravitational interactions, General Relativity for short.

The reason for the pessimist statement above is that this is only one of the numerous events that have been organized around the world to celebrate this important discovery. Now that the term ended, scientists are more free to travel to conferences and workshops and, to save time and money, it's very common to go directly from one conference to another on the week after. This does not leave too much time to sit down and do "actual" work.

Last week I've attended a very interesting workshop on Perturbation Theory which was organized here at the Field Institute as part of the Focus Program. This week instead the Institute is hosting a conference on Black Holes which ends today. Speakers at the conference included Clifford Will, Saul Teukolsky, Robert Wald, Eric Poisson, Gary Horowitz and William Unruh, to mention a few. Personally, I found the workshop much more stimulating and useful than the conference, but it's certainly suggestive to take the opportunity to discuss with some of the fathers of modern General Relativity.

This coming summer will be very busy with other events, especially in July and August, so I tend to agree that year 2015 will not be the most fruitful one in terms of actual work done.

On the other hand, do not underestimate the importance for the community to gather together and discuss open problems and (possibly) crazy ideas! Peer discussion and new collaborations are at the core of the scientific process and they are a crucial part of the duties of any scientist.  For this reason I am positive that the discussions and the collaborations that originate during these meetings will certainly contribute to solve open problems in the field and, who knows, perhaps the next breakthrough is just around the corner in 2016!

Doing a short tour of Toronto with Helvi Witek. Helvi was Ph.D. student in Lisbon when I moved there 4 years ago and she is now postdoc at Cambridge University working on numerical simulations of black-hole systems.