## RECENT POSTS

Your smartphone may not throw away gas as you use it, but be sure that it is a source of greenhouse pollution. “The emissions associated to keep an internet server working are around 3 metric tons of CO2 per year, comparable to those of gasoline burned by car in the same time, 4.75 metric tons”, says Zhenhua Liu, a researcher in IT and sustainability at the California Institute of Technology, who points out that the emissions of IT in the... **Read more**

Looking back on this year's Heidelberg Laureate Forum, what comes to mind are less the separate talks - splendid though a number of them were - but the connections. A key characteristic of the HLF, after all, is that you are not getting to hear a nice talk, and then have a long time to ponder its implications. With the exception of Wednesday - institute excursions and boat trip - it's a barrage of talks, and some of them connect... **Read more**

After the fall of the Roman Empire, a dark age came in which a large part of the ancient knowledge was lost in Europe. Manuscripts were destroyed in wars and fires, or became illegible before getting transcribed. Much of their content had to be re-discovered, but it took centuries to recover it. We may be at a similar turning point, according to Vinton Cerf. The computer scientist and “father” of the Internet warned at the Heidelberg Laureate Forum that we... **Read more**

On Monday, Sir Michael Atiyah spoke about beauty in mathematics. Shigefumi Mori’s talk on Thursday started with an interesting meditation on similarities between mathematics, design, and impressionist paintings. Where Atiyah’s talk was very general, Mori drew specific parallels between the process of creating math and creating art. Mori described both art and mathematics as trying to “capture an object and create a piece of work.” This language of “capturing” a property of an object made the similarities between math and... **Read more**

Anna Valmero, participant #hlf14: Humans of today will be ghosts in history unless the challenge of digital preservation is addressed. This was the challenge posed to attendees of this year’s Heidelberg Laureate Forum by Turing Awardee Vint Cerf, TCP/IP co-designer who, together with Bob Khan, is regarded as the father of the Internet (although he himself insists that it took the work of thousands of people to realize the Internet from its military roots to a powerful, complex organism it... **Read more**

In part 1 of "The rough worlds of Martin Hairer", I explored some of the basics and some of the background behind stochastic differential equations, guided by the content of Martin Hairer's HLF talk on Tuesday morning. Now, it's time to look at applications. And that is, at first sight, something completely different. How to grow an interface Imagine an interface, that is, a surface separating two different materials (or phases of the same material), as seen from the side... **Read more**

Thilo Küssner, official #hlf14 blogger for the german blog section: If mathematicians want to illustrate the development of their discipline in the last 30 years in Korea (where I am currently working) they like to mention that the number of publications of Korean mathematicians in scientific journals increased during this period from 3 (three) in 1981 to currently more than 50,000 (fifty thousand) each year. These figures might give the impression that there would have been no Korean mathematician thirty... **Read more**

Martin Hairer's talk on Tuesday, "Taming infinities", was a fascinating tour of his main area of research, which combines random processes with mathematic's preferred way of describing changing systems: differential equations. Trying to understand the basics of what Hairer was talking about was the most fascinating journey I've taken at this year's HLF (so far!), and I want to (try and) share this with readers of the HLF blog. I won't presume more than basic calculus, and even that will... **Read more**

John Tate tells the following story of how he enjoyed math when he was young, but didn't think he could ever do research in it. In 2010 he won the Abel Prize "for his vast and lasting impact on the theory of numbers." *** When I was in high school I read this book called Men of Mathematics by E. T. Bell. Each chapter is a bio of one of history's greatest mathematicians. It starts with Archimedes, Newton, … I... **Read more**

The world’s favorite number is seven, at least if the result of a poll conducted by Alex Bellos is to be believed. Some people like it because it is prime, some because they have a lot of sevens in their birthdates. But Manjul Bhargava’s talk Thursday morning gave us another reason to love this number: exponential Diophantine equations. Diophantine equations, named after the mathematician Diophantus of Alexandria, are equations relating several unknown quantities in which we are only concerned with solutions... **Read more**