Joseph Gran

From Santa Fe Institute Events Wiki

Hey everyone!

Email: gran at

About me

I am a 3rd year Phd student in the physics department at the University of California, Davis. I was born and raised in Menlo Park, CA which is about 30mi south of San Francisco along the penisula. I attended Chico State for my undergrad, where I recieved a bacholers degree in physics. I spent most of undergrad career doing research in an optics lab. In fact, I was lucky enough to spend a few years working for a private reasearch company, Advanced Light Technologies, where we developed a laser treatement for Trichophyton rubrum (toe-nail fungus).

I've been a huge Oakland A's fan for as long as I remember and try to go to as many games as possible. In fact, I was lucky enough to be at the game on Mother's day when Dallas Braden threw a perfect game! I still can hardly believe it happened. :-)

I love the outdoors and when I'm not at a ball game on the weekends, I usually am hiking in the nearby Sierra Nevada mountains. I'm looking forward to being in Santa Fe, I hear there are great hiking trails all around. Immediately after the summer program ends I'm headed up to Denver to go backpacking with my older brother in the Rockies for a week. It should be a great time.

I enjoy gardening and taking care of my yard, although i don't really know much about what I'm doing ... I have two gardenia plants in pots whose leaves are slowly turning yellow. I hope its not the start of the end for them.

I try to exercise when I can, usually in the form of playing, whether it be softball or soccer or golf.


Current Phd Research

I'm studying occurence of earthquakes and material failure as a generalised phase transition. We employ methods of statistical mechanics, namely nucleation phenomena, critical points, scaling behaviour and spinodals. My current project is to add a new parameter, damage, to the long-range slider-block model. The slider-block model is a simple "toy" model of earthquake faults in which a grid of blocks connected to each other with springs are dragged along a frictional surface. Every time a group of blocks slips forward we call that an event (earthquake). This simple model produce the same scaling behaviour seen in size vs. frequency distribution of earthquakes, namely the Gutenberg-Richter distribution. We have added a static friction threshold weakening parameter that controls the frequency of events that span the entire grid of blocks. We have been able to define an order paramter in the same fashion as that of percolation theory, and show that our new weakening parameter acts a scaling field.


I have studied statistical mechanics, percolation theory, driven threshold (self-organized) systems, non-linear dynamics and have general physics knowledge. I am familiar with several models that exhibit critical behavior, namely the sand-pile model, forest-fire model and aforementioned slider-block model.

My research is done primarily through computer simulations. For the most part I use Monte-Carlo methods, although ocassionaly I am force to solve differential equations. I write code in both C++ and python. I mainly use C++ for my simulations and python for data analysis. I also know gnuplot.


CSSS is sure to be a great experience for everyone involved. I am very much looking forward to meeting everybody. We have a very smart and hardworking group of people from various research backgrounds coming together. I look forward to working on cross-discipline research projects where the views of a physicist (me) might provide a new interpretation of the problem at hand. I am hoping to make new connections and meet new friends. With so many opportunities in front of me as I work to complete my PhD, I expect this summer program will provide a glimpse of what types of research are available to me in my future.

Project Ideas

I have recently become interested in the complex behavior of the financial markets. I'm not a finance guru, but I sense that there are many aspects of self-organized criticality in the financial market. One question to look at first might be to determine if stock prices or groups of stocks are effectively ergodic over any time scale.

I would be very happy working on any type of project from any discipline. I'll continue to think of more ideas.