By research in pure science I mean research made without any idea of application to industrial matters but solely with the view of extending our knowledge of the Laws of Nature. I will give just one example of the ‘utility’ of this kind of research, one that has been brought into great prominence by the War - I mean the use of x-rays in surgery. Now, how was this method discovered ? It was not the result of a research in applied science starting to find an improved method of locating bullet wounds. This might have led to improved probes, but we cannot imagine it leading to the discovery of x-rays. No, this method is due to an investigation in pure science, made with the object of discovering what is the nature of Electricity. The experiments which led to this discovery seemed to be as remote from ‘humanistic interest’ - to use a much misappropriated word - as anything that could well be imagined. The apparatus consisted of glass vessels from which the last drops of air had been sucked, and which emitted a weird greenish light when stimulated by formidable looking instruments called induction coils. Near by, perhaps, were great coils of wire and iron built up into electro-magnets. I know well the impression it made on the average spectator, for I have been occupied in experiments of this kind nearly all my life, notwithstanding the advice, given in perfect good faith, by non-scientific visitors to the laboratory, to put that aside and spend my time on something useful.
From a speech of Sir J. J. Thomson made on behalf of a delegation from the Conjoint Board of Scientific Studies in 1916 to Lord
Crewe, then Lord President of the Council (from "J J Thomson and the Cavendish Laborarory in His Day" by G P Thomson (New York: Doubleday) 1965 pp 167-8)
Announcements
new!: 2021, a book for a large non-specialised audience is out from Springer! The title is A Random Walk in Physics: Beyond Black Holes and Time-travels and I authored it together with three old friends: Massimo Cencini, Davide Vergni and Angelo Vulpiani, it can be bought online for instance at amazon (kindle or rigid cover)
new!: 2021, the organisation of the conference for the 40 years of stochastic resonance has started! It will be held in Perugia from 13 to 15 September 2021.
new!: 2021, A course (second year) for Ph. D. students in Sapienza/Roma3 on Stochastic Thermodynamics, see the presentation
new!: 2020, the first SIFS school, will be held in LUCCA-IMT, from August 31 to September 10, 2020, see the website(school canceled for covid19 emergency)
new!: 2020, nominated Outstanding Referee for 2020, by APS
new!: 2020, we (with Caprini and Marini Bettolo Marconi) have published on Phys. Rev. Lett. a numerical study showing that "flocking" (at least at short-range) is present also in purely spherical repulsive active Brownian particles, i.e. that velocities spontaneously align even in the absence of explicit Vicsek forces
new!: 2020, A new course for Ph. D. students in Sapienza/Roma3 on Stochastic Thermodynamics, see the presentation
new!: 2019, A conference at Accademia dei Lincei on the origin of theoretical models, it will take place on the 27-29 November 2019. See the webpage. (The event has appeared also on the CNR journal )
new!: 2019, we (with Plati, Baldassarri, Gnoli and Gradenigo) have published on Phys. Rev. Lett, a numerical study of the full experimental setup for granular rotational diffusion, discovering a strong collective motion that emerges when density is large enough
new!: 2018, we (with Angelani, Baldassarri, Cecconi and Gnoli) have won a funding (150kEuro) for a project (MICROSORT) on the physics of sperm
new!: 2018, we (with Caprini, Bettolo Marconi and Vulpiani) have published on Phys. Rev. Lett a comment to a previous study on thermodynamics of active (living) matter, where we offer a possible solution to a debate about the proper definition of entropy production
new!: 2018, we (with Gnoli, De Arcangelis, Giacco, Lippiello, Pica Ciamarra and Sarracino) have published on Phys. Rev. Lett, a study of viscosity in dense granular media, which decreases abruptly at a thresold vibration frequency and is recovered at a larger vibration frequency
recent: 2017, online a video with a talk given at the ECEA4 conference on stochastic thermodynamics for active particles
recent: 2017, we (with Manacorda) have published on Phys. Rev. Lett, a study of a lattice model for inertial active particles which shows collective swarming, aster-like clusters and underdamped propagating waves
recent: 2017, we (with Sarracino and Vulpiani) have published a review paper on Physics Reports about the definition of temperature in and out of equilibrium in classical statistical mechanics
recent: 2017, we (with Bettolo and Maggi) have published a paper on Scientific Reports where entropy production and heat are connected - as in the Clausius relation - in a model of self-propelled (active) particles, like bacteria or sperm
(we have also compared our Clausius relation with other formula in a more recent paper )
recent: 2017, I am editing (with Sarracino and Vulpiani) a special issue of the "Entropy" journal on the theme "Thermodynamics and Statistical Mechanics of Small Systems"
2016, published on Scientific Reports, an experimental and theoretical study of granular rheology under vertical vibration (in collab. with A. Gnoli, A. Lasanta and A. Sarracino)
2016, published on New J. Phys, an experimental and theoretical study of the response velocity of a 3d-printed "walker" moving on a vibrating plate (in collab. with N. Koumakis, A. Gnoli, C. Maggi and R. Di Leonardo)
2016, published on Phys. Rev. Lett, a numerical study of the response of an inertial particle in a "rotating" flow, with very strange nonlinear effects (in collab. with Cecconi, Sarracino and Vulpiani)
2016, published on Phys. Rev. Lett, an experiment on granular thermal convection induced only by dissipative lateral walls (in collab. with Gnoli, Pontuale and Vega-Reyes)
2015: Spring 2015 seminars: during the spring of 2015 we had a lucky sequence of three seminars given by young colleagues who - in the recent past - have worked in our group, and are now exploring new interesting paths in non-equilibrium statistical mechanics; following the above link you can retrieve the titles, abstracts and slides of the three seminars.
2015-2016, a series of published papers on fluctuating hydrodynamics of granular fluids derived from a microscopic model (in collab. with Manacorda, Lasanta, Plata and Prados)
2015-2016, a series of published papers on statistical mechanics and thermodynamics of small systems and heat engines (in collab. with Cerino and Vulpiani)
2015, our research is covered by Nova (science&technology from Il Sole 24 Ore) here
2015, published on Phys. Rev. Lett, an experiment on cages and super-diffusion in a vibrated dense granular medium
2015: A Springer Brief on granular fluids:
2014: A Springer-LNP on Large Deviations:
2014: an experiment on non-equilibrium Fluctuation-Dissipation relation, performed in our Granular Dynamics Lab, published on Plos One (open access!)
2013: a Brownian motor ("ratchet") effect driven only by dry friction , published on Phys. Rev. Lett.
2011-2012: experiments on a quasi-2d granular fluid with non-equilibrium-induced ("dissipative") structures
2010: The Granular Dynamics Lab is open, have a look at the lab page
Courses
Corso 2' anno laurea specialistica in fisica (valido anche per dottorandi): Introduzione alla teoria dei processi stocastici e applicazioni in fisica : informazioni
Corso di dottorato (Ph. D.): Fluidized granular materials : program - lessons.pdf
Corso di dottorato (Ph.D): Introduction to stochastic thermodynamics : notes and videos
A very complete historical and conceptual introduction to Brownian Motion and the concept of velocity in it: preprint
Organised conferences
Anomalous Transport: from Billiards to Nanosystems conference held in Sperlonga from 20 to 24 September 2010, please visit the webpage
a workshop on Non-equilibrium fluctuation-response relations held in Giglio Island June 5-8, 2012, see webpage
a day on Quasi-fluids and quasi-solids: the dynamics of active and granular matter held during the XVII National Conference on Statistical Physics held in Parma, June 20-22, 2012, see website
a 1-month program on Small system nonequilibrium fluctuations, dynamics and stochastics, and anomalous behavior, July 1-26, 2013 in Beijing (China) at Kavli-China institute, see webpage
a conference on Large deviations and rare events in physics and biology September 23-25, 2013 in Rome at Sapienza University, see webpage
a conference on Strolling on Chaos, Turbulence and Statistical Mechanics September 22-24, 2014 in Rome at Sapienza University, see webpage
a small workshop on Statistical Mechanics of non-Hamiltonian systems May 12-13, 2015 in Rome at Sapienza University, see webpage
a conference on Thermodynamics and Statistical Mechanics of Small Systems September 18-20, 2017 in Rome at Sapienza University, see webpage
a conference on the origin of theoretical models November 27-29, 2019 at Accademia dei Lincei, Rome, see webpage. (The event has appeared also on the CNR journal )
Contacts
Dipartimento di Fisica - Università degli studi di Roma "La Sapienza" - p.le A. Moro 2 - 00185 Roma - Italy