Two articles in the June 2019 Issue of this journal inaugurate a Topical Collection series of invited papers. They are written or co-authored by scientists who have been recognized as winners of one of the numerous prizes that are annually awarded by Accademia Nazionale dei Lincei—specifically those belonging to the areas of Physical and Natural Sciences.

This Editorial serves also as an introduction to the new feature that of Topical Collections, inaugurated with the present Volume 30 of the journal. An additional motivation for this Editorial is that this issue is part of the Volume that marks three decades since Rendiconti Lincei is compiled more or less in the present form: This journal is always devoted to publishing papers either by members of the 416-year-old Accademia or anyway dedicated to keep track of its activities. Actually, publication of the series with a different name dates back to 1870 when Italy was unified and was established as a Nation: the Accademia is divided in two classes, it is only thirty years ago that it was decided to publish separately the proceedings that regard the Moral Sciences Class and so focus the Rendiconti Lincei series on publications related to the Mathematical, Physical and Natural Science Class. Later, the journal split in two: a separated series specialized on Mathematics, and this one, Rendiconti Lincei-Scienze Fisiche e Naturali. The former one is now published by the European Mathematical Society and the present one is published by Springer since 2008.

A direction of change indicated in this Volume 30 is the introduction of the feature Topical Collections, which is a more flexible evolution of the previous Special Issues, that provided contributions on a specific theme of current scientific research. In a similar spirit, papers under the heading “Topical Collections” are proposed and organized by Guest Editors who invite authors to contribute peer-reviewed original papers and reviews having the purpose of exhibiting the state-of-the-art on the specific areas, often but not necessarily originating from activities and events organized with the Sponsorship of the Accademia dei Lincei. A feature of Topical Collections will be that submissions may have no deadline and may remain open while papers are published online soon after acceptance and included in regular issues.

Within this framework, we considered appropriate to open a forum to Lincei Prize Winners for accounting on their scientific achievements: prizes go to both young scientists and to mature ones. Current members of Accademia cannot be Lincei prize winners, but they may have been such in the past; therefore, they too are welcome to give their contributions when motivated by results of their recent research.

A paper can be as long as needed and will not be a brief report: it should have little or no personal recollections, but it should bring perspectives and prospects on scientific progress. A state-of-the-art survey covering in-depth a specific research field is acceptable and original papers possibly involving collaborations are welcome; even a blend of the two is preferable rather than a rapid guide to wide areas, listing a comprehensive but dull bibliographical databases.

We already have in this issue two articles illustrating two possible formats: The origin of water on Earth: stars or diamonds? A conversation among astronomers and geologists, by Rossella Spiga, Cesare Barbieri, Ivano Bertini, Monica Lazzarin, Fabrizio Nestola (the last author was the recipient of the 2016 Prize for a Scientist, established by the Foundation “Maria Teresa Messori Roncaglia ed Eugenio Mari” and awarded by the Accademia Nazionale dei Lincei); Quantum mechanics in Earth sciences: a one-century-old story, by Mauro Prencipe, who has been awarded with the 2018 Lincei Prize on Geosciences. We have disseminated invitations to recent prize winners, less recent ones and all who feel fit to be contributors can write to the Editor.

We take the opportunity to indicate that in this same issue several papers appear that belong to current Topical Collections Classical and Quantum Plasmas (Editors V. Aquilanti, M. Capitelli and F. Pegoraro), Foreseeing Groundwater Resources (Editor G. Orombelli) and Solar Driven Chemistry (Guest Editors G. Pacchioni, V. Balzani, M. Prato, A. Zecchina): they are written, peer-reviewed versions of presentations given at Conferences held at Accademia Nazionale dei Lincei in Rome on March, April and October, 2018.

Finally, a Topical Collection is presently open and papers are available online: A Decade of AGILE: Results, Challenges and Prospects of Gamma-Ray Astrophysics (Editors M. Tavani, A. Cavaliere, F. Matteucci, G. Setti), soon to be assembled as a Supplement and collecting about 30 contributions selected among those presented at the Conference on “Gamma-Ray Astrophysics with the AGILE Satellite”, held jointly at Accademia Nazionale dei Lincei and at Agenzia Spaziale Italiana, Rome on December, 2017.

Vincenzo Aquilanti, Editor-in-chief, Rendiconti Lincei-Scienze Fisiche e Naturali

Annibale Mottana, Deputy Editor-in-chief, Rendiconti Lincei-Scienze Fisiche e Naturali