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Gothic Majesty of Siena

Duomo di Siena
Duomo di Siena
Streets of Siena's medieval center
Streets of Siena’s medieval center
Basilica di San Domenico
Basilica di San Domenico

Truth be told, the real gems of Tuscany are the historic town and cities. One of my favorite is the Gothic majesty of Siena. Legend tells us that Siena was founded by the son of Remus, and the symbol of the wold feeding the twins Romulus and Remus is as ubiquitous in Siena as it is in Rome.

The streets of Siena’s medieval center are humongous and gorgeous. During the day the stone ground sizzles under the sun and the wonderfully crafted buildings bake from exposure from an incredible clear sky. To be on the safe side and because I love film grain, I decided to load my camera with an ISO 200 Fuji film to capture the town (click on the photos to enlarge them and to see the grain).

Our first stop was Duomo di Siena, a cathedral originally designed and completed between 1215 and 1263 and Siena’s main landmark. The dome rises from a hexagonal base with supporting columns. The magnificent facade of white, green and red polychrome marble was designed by Giovanni Pisano. The lantern atop was added by Gian Lorenzo Bernini.

Later we visited the Basilica di San Domenico, which was constructed between 1226 and 1265, but was enlarged in the 14th century resulting in the stunning Gothic appearance it has now. In the afternoon we continued to stroll around Siena and had plenty of Gelati at Palazzo Publicco…

bitcoin.de: Erster deutscher Marktplatz für Bitcoins

Bitcoins sind derzeit auch bei uns am CERN ein brandheißes Thema. Innerhalb weniger Wochen stieg der Wert eines Bitcoins (BTC) von 20 Cent im Dezember 2010 auf Größenordnungen von bis zu 30 Dollar. Dennoch lohnt sich das Mining kaum, zumindest nicht zu den aktuellen Strompreisen.

Die Bitcoin-Börse bitcoin.de schafft hier nun Abhilfe! Ein gutes halbes Jahr später, am 26. August 2011, hat der erste deutsche Marktplatz zum Kaufen und Verkaufen von Bitcoins den Handel aufgenommen. Auf bitcoin.de können User auf einfache Art und Weise Bitcoins an andere User verkaufen oder von diesen kaufen.

Dafür ist es erforderlich, dass sich die User bei bitcoin.de registrieren und, insofern sie als Verkäufer auftreten wollen, auf ihr Benutzerkonto ein Bitcoin-Guthaben übertragen. Sobald für die eigenen Bitcoins ein Käufer gefunden wurde, werden automatisch alle Informationen zur Bezahlung an den Käufer übermittelt.

Die Bezahlung der Bitcoins erfolgt direkt zwischen Käufer und Verkäufer. Erst wenn die Zahlung beim Verkäufer eingegangen ist, werden die Bitcoins abzüglich einer geringen Gebühr aus dem Guthaben des Verkäufers in das Guthaben des Käufers übertragen.

CERN: The world’s first website went online 20 years ago today

CERN website dispayed in Line Mode Browser
CERN website dispayed in Line Mode Browser

On this day 20 years ago the world’s first website went live. The website, created by Tim Berners-Lee at CERN, was a basic text page with hyperlinks and went live on August 6, 1991.

The website was hosted on Berners-Lees’ NeXT computer, the first web server ever, which had a note taped to the front that said: “This machine is a server. DO NOT POWER DOWN”.

NeXT computer used as first World Wide Web server
NeXT computer used as first World Wide Web server

Today this computer is displayed in the CERN Computer Center, which is just located next to my office.

[Update 30 Apr 2013]: CERN is bringing the very first website back to life at its original URL. If you’d like to see it, point your browser to: http://info.cern.ch/hypertext/WWW/TheProject.html

Data Science: Enabling Research at CERN with Big Data

Wow, time flies. One year has passed since I started to work at CERN as a data scientist. CERN, surrounded by snow-capped mountains and Lake Geneva, is known for its particle accelerator Large Hadron Collider (LHC) and its adventure in search of the Higgs boson. Underneath the research there is an tremendous amount of data that are analysed by data scientists.

Filters, known as High Level Triggers, reduce the flow of data from a petabyte (PB) a second to a gigabyte per second, which is then transferred from the detectors to the LHC Computing Grid. Once there, the data is stored on about 50PB of tape storage and 20PB of disk storage. The disks are managed as a cloud service (Hadoop), on which up to two millions of tasks are performed every day.

High Level Trigger data flow
High Level Trigger data flow, as applied in the ALICE experiment

CERN relies on software engineers and data scientists to streamline the management and operation of its particle accelerator. It is crucial for research to allow real-time analysis. Data extractions need to remain scalable and predictive. Machine learning is applied to identify new correlations between variables (LHC data and external data) that were not previously connected.

So what is coming up next? Scalability remains a very important area, as the CERN’s data will continue to grow exponentially. However, the role of data scientists goes much further. We need to transfer knowledge throughout the organisation and enable a data-driven culture. In addition, we need to evaluate and incorporate new innovative technologies for data analysis that are appropriate for our use cases.

Top 10 Angels&Demons Questions

CERN Exhibition: Top 10 Angels&Demons Questions
CERN Exhibition: Top 10 Angels&Demons Questions

Gestern haben wir Angels & Demons (deutscher Titel: Illuminati) im Kino gesehen. Die Verfilmung des gleichnamigen Bestsellers von Dan Brown war vor allem visuell sehr ansprechend. Tom Hanks hat wie schon in Da Vinci Code souverän die Rolle des Protagonisten Robert Langdon verkörpert.

Ein Teil der Handlung des Films spielt am CERN. Tatsächlich wurden einige Einstellungen am ATLAS-Detektor des LHC gedreht. Regisseur Ron Howard sah sich ebenfalls das CERN-Gelände an, um den Film authentischer zu gestalten. Die Herstellung einer Bombe aus Antimaterie ist hingegen ebenso Fiktion wie die “Schöpfung aus dem Nichts”, welche im Film lediglich dazu dient den Konflikt zwischen Religion und Naturwissenschaft zu entfachen.

CERN hat Angels & Demons eigens eine Ausstellung (siehe Foto oben) und eine Website gewidmet, um “the science behind the story” zu erläutern und auf häufig gestellte Fragen (“Does CERN create black holes?”, etc.) einzugehen.