I've been to a few Trance events, like the Armin Only concerts. In early 2020 there has been a large festival with A State of Trance (ASOT) Episode 950 in Utrecht. Together with a friend I bought tickets and went there.

My sleep cycle usually has me spending the hours from like 23:00 to 06:00 in bed. Going to a concert which goes from 22:00 to 06:00 was going to be quite exhausting for somebody who is not nocturnal. I tried to sleep in but could only get to 10:00, so it was going to be around a 24 hour shift.

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In the summer of 2019 I was able to spend four weeks in China. One week during The 37th Annual International Symposium on Lattice Field Theory (just "Lattice 2019" by the people in the field) in Wǔhàn (武汉市) and three weeks during a summer school "Frontiers in Lattice QCD" in Běijīng (北京市).

You can find all pictures in the Google Photos album. I have a bunch of images in this articles, but I took too many to show them all here. This article contains 19,029 words and 111 images. Have fun!

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This trip to Groningen is the sequel to my last bike trip to Utrecht & Holland. My brother was finishing up his studies in Groningen, so I took the opportunity to visit him there and take a look at the city.

The booking process via the telephone was quite cumbersome last year, so this time I just searched the connections for one that was suitable and booked it in the Reisezentrum at the main station in Bonn. The process was really smooth as the agent just entered my details, I payed with debit card and got printout of all the tickets. Again there was a slew of documents for both ways of the trip:

1. Travel itinerary
2. Train ticket for me
3. Bike ticket
4. Reservation for bike rack

The connection that I got had a bunch of transfers:

Bonn → Düsseldorf → Arnhem → Zwolle → Groningen

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København has been on my list of cities to visit for a while. Recently my friend Chris's girlfriend started her PhD in that city and moved there. He had invited me to visit them there, and that it what I have done in this trip.

As the city is known for its cycling infrastructure, I have done this trip with the bike in mind; similarly to the trip to Utrecht & Holland.

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In September 2018 the collaboration that I am part of, the European Twisted Mass Collaboration, short ETMC, had one of their bi-annual meetings in Poznań, Poland. This time I got to attend the meeting as well.

As usual I have researched train connections first. At the time of booking there were only connections with around 5 transfers and a bus connection over the border. Trips would have taken around 12 hours from Bonn to Poznań. However at the time of writing this article there seemed to be a somewhat sensible connection taking about 8 hours:

• Bonn to Köln with IC
• Köln to Berlin with ICE
• Berlin to Poznań with EC

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Going on bike trips around Bonn is not so much fun. The roads near the Rhine river are too small for pedestrians and cyclists going both ways. In the city the bike infrastructure feels like a timid afterthought. During a vacation to Zeeland in the Netherlands a couple of years ago we had amazing bike trips. At some point I wanted to do a longer bike trip in the Netherlands, and I just did the first one of them in the region of Utrecht and Holland. I took my bike in the train to Utrecht, rode it from city to city and took it back home in the train from Rotterdam.

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In May 2018 I have been in Dublin, Ireland, for the "Scattering on the lattice: applications to phenomenology and beyond" workshop. It was a stay from Sunday to Saturday.

The workshop was held at the "Hamilton Mathematics Institute" at the "Trinity College Dublin". During the week we sat in a windowless lecture theater in this building:

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In Februar and March of 2018 we have been at the "Hacienda Buena Suerte" again. This time we took the ICE train from Siegburg to Frankfurt and then the plane to Sevilla. I really like traveling with the ICE, especially on that particular connection where it displayed 301 km/h at one point.

While I was there I hiked a bit around the ranch, there is plenty of space to spend a couple hours.

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In the fall of 2017 my family took me to Mallorca. Even though it is also known for the chaotic German and British tourists, there is a lot of nice landscape for hiking as well as the Mediterranean Sea. We had booked a holiday house in Can Picafort.

The cheap flight that we had booked took us to La Palma in the evening. As we were six people my parents booked an airport transfer and we got picked up in a large taxi. The ride was surprisingly fun as the driver engaged in our conversation. At the Köln-Bonn Airport wer did not have to wait long until we could check in our luggage and go through the security check.

The flight itself was uneventful, the fun started when exiting the plane in La Palma. Even though drunk tourists were to be expected, I was still taken by surprise that a group of young German men carried a five liter party keg of Kölsch beer. As I left for the restroom I overheard them or a similar group notifying the others vocally that they had to urgently pee. Judging by the moaning sounds from the stall they had already made a big dent into that party keg on the flight. These are the moments where I am a bit embarrassed to share the nationality.

Outside the airport we called the car rental service and got picked up. The cheap rental services are usually a bit away from the airport and you need to take a shuttle. Once there it took ages until we got our cars. Then we need to drive to the other end of the island in the dark. Google Maps navigation routed us through smaller and smaller roads until we got a gravel one. We turned around and eventually made it to the holiday house. There a huge platter with fresh fruit and vegetables was waiting for us, a very pleasant welcoming gift.

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In March 2017 I got invited to the CINECA supercomputing facility in Casaleccio di Reno near Bologna in Italy. They had recently installed their latest system, the Marconi A2 powered by Intel Xeon Phi 7250 CPUs. My colleague Peter and I had worked on the QPhiX library which explicitly targets these type of processors.

Both of us applied for this two day workshop and got accepted with our talk. Although the workshop started at noon and ended at noon the following day, it was cheaper for us to stay two more nights and take other flights. Fortunately Lenovo covered both the flight and the hotel, so this trip was pretty much a gift. Also we did not have to book anything, we just got a flight ticket send to us.

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Für heute war unsere Exkursion nach Brüssel angesetzt. Brüssel klingt ja nach einer potentiell interessanten Stadt. Und was soll schon schief gehen, wenn sich 12 Physiker, Mathematiker, Chemiker und Informatiker mit dem Auto auf den Weg machen?

Spannenderweise hat sich erst gestern spät abends geklärt, wann wir eigentlich heute losfahren wollen. Irgendwann setzte einer einfach 9:00 fest.

Am nächsten Morgen bin ich irgendwann wach geworden und es war 8:25. „Verdammt" dachte ich und machte mich fertig. Für Frühstück war dann allerdings keine Zeit mehr. Für frisches Brot holen erst recht nicht mehr. Also habe ich mir Knäckebrot für die Fahrt geschmiert. Später habe ich herausgefunden, dass der Wecker nicht geklingelt hatte, weil der eigentlich nur für Wochentage (die ich normalerweise in Bonn bin) aktiv war. Gut, mein Fehler.

Um 9:01 war ich dann unten vor dem Gästehaus. Jedoch waren nur drei andere Gaststudenten dort -- nicht die ganze Gruppe. Super, dann hätte ich ja noch in Ruhe frühstücken können. Dann kamen so nach und nach die Leute herunter. Der eine hatte nur ein T-Shirt an. Seine Freundin wies ihn dann darauf hin, dass er sich doch vielleicht noch etwas anziehen sollte. Also ist er dann mit dem Aufzug erstmal nach oben gefahren …

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Am Dienstag sind wir noch einmal die Sophienhöhe rauf gefahren. Uns wurde noch der Tagebau gezeigt und etwas zur Geschichte der Sophienhöhe erzählt.

Das hier war die Tour:

Und noch das Höhenprofil:

Auf nassen Sandstraßen mit Rädern mit nur einem Gang durchaus eine Herausforderung.

In spring of 2015, we have been at Hacienda Buena Suerte.

This is is the main building where our room was located in:

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In my German high school I took the intensive physics course (Leistungskurs). The university of Bonn organized a so called "Master Class of Particle Physics". A couple of students of each high school would get to attend, and I got to participate.

At the time I did not know much about physics, so I did not know about the divide into theoretical and experimental physics. Also I did not have any opinions about the two sides and would have an idea what (usually humorous) grudges each have against the other. So we had a lecture by the experimentalists about particle physics and how they are detected. Basically we looked at electron-position-collisions and their results into leptons (electron, muon, tau) and hadron jets. We would learn to classify these events. Incidentally I did this later on in the lab course during my studies with a computer program. More accurate and much faster.

On the second day we were sitting in a computer room and were tasked to go through 100 events. Each team of two got different events, and in total we were around 10 groups. We classified around 1000 events on that day. Then later we had a video conference with the organizers of the class from CERN. Michael was a senior employee working in the outreach program, Daniel a PhD student if I recall correctly. During that conference each university would transmit their results and the people at CERN tally them up. In the end we got a result with around ten thousand events.

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In 2009 we had two school trips to choose from: Barcelona in Spain and Prague in the Czech Republic. I chose the latter mostly because the bus ride would be shorter.

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