High Energy / Particle Cosmology / Living Matter
Research
- Astrophysics & Cosmology read more ...
The astrophysics group in the Department of Physics and Astronomy at Penn currently consists of seven full time faculty, one lecturer, and a number of post-doctoral fellows, full-time staff, and graduate students. We are in the process of hiring more faculty and plan to continue expanding our group over the next several years. The astro group at Penn has a very strong experimental and theoretical interests in cosmology. We are specially strong in cosmology, galaxy evolution and stellar populations. There is a vibrant collaboration with the string cosmology group at Penn. We also do research on numerical astrophysics. Our areas of research include Kuiper-Belt objects, dark matter search, dark matter halos, large scale structure, galaxy formation and evolution, the cosmic microwave background, and the development of new astronomical instrumentation and telescopes. Our research activities cover the full spectrum -- computations, instrumentation, observation, and theory. There are many exciting projects for students to join.
- Biophysics read more ...
There is a cultural gap between physics, which seeks to understand extremely simple systems, and biology, which is obliged to study the overall behavior of extremely complex systems. One area where simplicity and life intersect is the study of biomembranes, both in isolation and as active elements of cells. In recent years amazing new experimental techniques, including optical tweezers, have opened up the study of both the equilibrium conformations and dynamic response of membranes to quantitative analysis. Similarly the DNA molecule, while architecturally complex, has remarkably simple elastic behavior governed by just a few parameters. Apart from their potential relevance to biology, the study of these systems has revealed new physical phenomena characteristic of the highly-fluctuating micron world. At UPenn we currently have groups developing the theory of lipid bilayers, the physics of single DNA molecules, as well as the structure of condensed DNA in vitro and in vivo.
- Condensed Matter read more ...
Condensed Matter physicists study matter in its nearly unlimited variety of condensed states from liquids to crystalline solids, from thin films to fabricated nanostructures, from quantum Hall electron gases to superconductors, from carbon nanotubules to liquid crystals, and from amorphous structures to complex fluids. We seek both to clarify the fundamental issues behind the striking properties of these systems, and to illuminate their potential for useful application. Condensed matter physics underlies many key devices of information technology, including the transistor, the solid-state laser, optical fiber, magnetic storage media, and the liquid crystal display.Much of the explosive growth in Condensed Matter Physics in the last decade has come at the mutual boundaries of physics, chemistry, and materials science. Recently in ever more dramatic ways, this intellectual cross-fertilization is producing key discoveries at the convergence of these fields and biology. The Penn Condensed Matter Physics group helped to create this fruitful trend, and many of our projects are highly interdisciplinary in nature.
Penn has a long and successful history of forefront research in condensed matter physics with seminal contributions to superconductivity, conducting polymers, liquid crystals, colloidal physics, and many other fields. There are currently 7 experimentalists and 7 theorists pursuing research in many areas of condensed matter physics.
- High Energy read more ...
The goal of particle physics is to understand what are the most fundamental constituents of matter and how these elementary particles interact. The next few years hold great promise for major advances in our understanding of this field of physics, both in theory and in experiment. Several new experimental facilities have just begun operation or will begin operation soon. These facilities will address fundamental questions such as
- What is the origin of electroweak symmetry breaking and mass (the Higgs sector)?
- Are there additional fundamental particles (e.g. supersymmetric partners of the known particles)?
- What is the origin of the matter anti-matter asymmetry in the Universe?
The answers to these questions not only affect the understanding of elementary particle physics; they can also have important implications for cosmology and the large-scale structure of the Universe. Theoretical particle physics is focused on understanding whether there is a unified theory that explains all elementary particles and their interactions, including gravity. The most promising approaches such as string theory and brane theory also involve modern mathematics. One of the biggest challenges is to extract unique predictions from these theories that can be verified by experiment.
The Penn high energy physics group is active in both experiment and theory. Experimentalists in the Penn faculty are working on ATLAS, SNO+, and LBNE
- The goal of ATLAS is to discover new particles by studying proton collisions at the highest energies ever achieved in a lab. ATLAS is one of the experiments at the Large Hadron Collider (LHC) at CERN, Geneva, Switzerland. Penn scientists are searching for the missing piece of the standard model, the Higgs boson, in several possible decay channels including two photons, two tau leptons, and two W bosons. We are searching for new exotic massive gauge bosons (W' and Z'), and for supersymmetry. We contribute significantly to the operation of the ATLAS Transition Radiation Tracker (including design and commissioning of front-end electronics and DAQ), to the crucial trigger system that selects the collisions kept for future physics analysis, and to future upgrades for the ATLAS detector.
- SNO+ uses the existing Sudbury Neutrino Observatory in Canada, but with the heavy water replaced with 780 tonnes of liquid scintillator. SNO+ will perform a search for neutrinoless double beta decay with isotope Neodymium 150, and measure the low-energy fluxes of solar neutrinos.
- The Long Baseline Neutrino Experiment (LBNE) will use a neutrino beam from Fermilab and a detector located in the Homestake mine in South Dakota to provide precision measurements of the neutrino mixing parameters, with a focus on a search for CP violation in the lepton sector.
Penn has a very active and strong elementary particle physics theory group. Although many areas are pursued, the central thread is the unification of all interactions. This includes theoretical efforts in string and brane theory, phenomenological studies of the electroweak interaction, and attempts to connect the fundamental theory with experiment. There is also considerable activity in particle astrophysics, including inflationary cosmology, studies of the microwave anisotropies, and theoretical studies of solar and supernova neutrinos.
- Center for Particle Cosmology visit web site ...
In the last decade new data has transformed Cosmology into a mature, empirically grounded physical science. The next decade will see vast increases in astronomical data and qualitatively new observationally regimes, including that opened up by gravitational wave astronomy, with the potential of opening a window into the earliest times in the Universe.
Now is also a particularly exciting time for particle physics. The LHC will help determine what models of fundamental physics are valid beyond the scales probed by existing experiments. Candidate theories of physics beyond the standard model generically predict new physics in collider experiments with important ramifications for cosmology.
Thus, upcoming experiments in both cosmology and particle physics will provide new data on dark matter, dark energy and the physics of the early Universe. How these fit into a coherent description at the level of fundamental physics is an open and compelling question: the breakthrough answers will come from theorists closely interacting with groups of talented experimentalists in both fields, and interpreting and building on their findings with new models and creative ideas. Precisely such a confluence of talented faculty now exists at Penn. Penn theorists have been at the forefront of developing new theoretical idea to address cosmological problems, and Penn experimentalists are playing leadership roles in a suite of new experiments that are in the construction, research and development, or planning stages.
Particle cosmology is an interdisciplinary effort between fields with different cultures, funding sources, conferences, and languages. The Center for Particle Cosmology facilitates unfettered interactions and collaborations between these traditionally separate groups, thus creating a new entity with day-to-day interdisciplinary activity. Our mission is the connection of cosmology with new ideas in fundamental physics, directly testable both through the current flux of data from observational cosmology and imminent new particle physics experiments.
- Physics of Living Matter visit web site ...
The Physics of Living Matter group in the Department of Physics and Astronomy at the University of Pennsylvania studies how organisms gather, process and respond to information. Much of our work focuses on computation and communication in the brain, but group members also work on cell signaling and regulatory networks. The group exploits theoretical and computational approaches from physics, statistics and computer science, and relies on experimental data gathered both within our lab and by collaborators at Penn and elsewhere.

