David Bailey - Opportunities for Students
If you are looking for summer research opportunities, your first stop should be our Summer travel, employment and research opportunities page. If you are interesting in working on any of the following projects, please contact me at email@example.com to find out if I have any openings.
An important prerequisite is that you enjoy doing hands-on experiments and connecting physics to the real world through measurement and data. For these projects, undergraduate students will be enrolled in either a Physics Supervised Study or Research course, an Advanced Physics Lab course, or an Engineering Science thesis. Students may have a better experience and be more productive if they are not working alone, so if you and a friend are both interested in a project, feel free to apply together.
If you are a high school student, please look at my High School Students section below.
Energy Conservation is perhaps the most fundamental law of physics. When apparently violated in experiment, it is always because energy is leaking in or out invisibly; any theoretical model that does not include energy conservation is at best a useful approximation.
Physics knowledge is, however, always qualified by experimental or observational uncertainty. For example, the Review of Particle Properties summarizes the experimental constraints on everything from extra dimensions to new Z' bosons to electric charge non-conservation. It is therefore surprising that it is not easy to find explicit constraints on energy non-conservation.
Searches for missing energy constrain theories with (almost) invisible particles, e.g. neutrinos, axions, or neutralinos, or theories with extra spatial dimensions into which the energy might leak. Searches for the appearance of expected energy constrain new physics such as dark matter (e.g. WIMPs), violations of conservation laws (e.g. electron decay), or universal scalar fields (e.g. continuous spontaneous localization).
There is even a infinitesimal chance that energy might simply not always be conserved. Many popular "theories of everything" have extra spatial dimensions, so why not extra time dimensions? It turns out that it is appears essentially impossible to construct a sensible theory with more than one normal time dimension because energy conservation and causality get tossed out the window. Something like a gauge symmetry must be imposed to eliminate these problems (e.g. Two-Time Physics), but what would happen it this symmetry were broken, even by a tiny amount?
Researching limits on energy conservation requires compiling results from a wide variety of experiments and observations, and then organizing these results in a coherent manner. There is no easy way to parameterize energy non-conservation to compare the relative strength of these different limits.
I once asked students in Experimental High Energy Physics course to design a Planck Scale particle accelerator using only extrapolations of known physics, and assuming that a sufficiently advanced civilization might have a few million-year attention span. There was no "right answer" to this question, but my answer sketched some of the issues for the students. It would be fun to develop this answer further and maybe even set a limit on how close the nearest Planck Accelerator might be.
Undergraduate Lab Projects
Possible undergraduate projects depend on my current interests and what equipment we have available. Many examples are listed as Advanced Physics Lab Special Projects, and other possibilities include:
Current Experiment Development
- Our new Earth's Field NMR/MRI experiment is strongly affected by spatial and temporal variations in the local magnetic field. We are working on active real-time compensation using fluxgate magnetometer feedback, and also plan thick passive shielding against noise.
- We would like to further develop Python analysis and modelling tools for our experiments. The desired tools include multi-peak fitting for experiments such as gamma ray and Mössbauer spectroscopy, and improved modelling of experiments such as Conductivity in less than 3 Dimensions.
- New experimental possibilities would open up if we had improved video tracking and measurement of objects for both existing and new experiments. We have used ImageJ and MatLab, but are currently moving to Python, using PIL and OpenCV.
All computational projects are designed to help other undergraduate students, so clarity, simplicity, and good documentation are more important than achieving maximum computational efficiency and speed.
Blue Sky Projects
I always have a few ideas kicking around the back of my head, but which are either low-priority, poorly defined, or not yet practical:
- Is it possible to observe parity violation in the undergraduate lab in a reasonable amount of time? We used to have an experiment that measured the muon magnetic moment and demonstrated parity violation, but removed it because it took at least 4 months for a successful measurement. It was both too complicated and too small.
Students and I have worked on designing an improved experiment using a water or oil absorber, basically a micro-Super-Kamiokande with only one or two phototubes. We have yet to come up with a workable low-cost design. ("Workable" is easy; "low-cost" is not.)
An alternate would be to study double scattering of beta rays, but the radioactive sources normally used in such experiments are a 1000 times hotter than we typically like undergraduates using.
- Is it possible to observe special relativistic effects in a first year experiment?
Experiments for first year students must be inexpensive, easy to duplicate, and doable in just a few hours. An easy way to observe special relativity is to simultaneously measure two of energy, momentum, or velocity for electrons at momenta comparable to their mass (i.e. mec). This is quite doable for under $10k, but can it be done for less than a few $k? One possibility is Compton scattering of Cs-137 photons in a small cloud chamber with a magnetic field, imaged by a a webcam. Just observing cosmic ray tracks in a cloud chamber and doing linear track identification and fitting would be a useful first step, since this would allow students to observe the intensity, angular distribution and East-West asymmetry of cosmic rays. (The flux of muons at sea level is about 1/cm2/minute.) We have a large new cloud chamber that can be used for these studies.
I am interested in what works and what doesn't for student learning, and how do we tell.
- I often say that the purpose of physics lab courses is to teach all of physics not taught in lecture courses. I have a particular interest in advanced physics lab and practical courses, both here and elsewhere. How can we assess our success in Advanced Lab courses?
High School Students
I am sorry, but I do not normally have projects for high school students. Students are often too keen to work too early in someone else's lab, when they might learn more in their own bedroom/kitchen/basement/backyard/school. Just pick a physical system that interests you, and try to understand it experimentally or theoretically. You should have fun, and along the way you are likely to pick up useful skills.
- For example, if you are inclined towards theory and literature searching, the kinds of questions answered at http://what-if.xkcd.com/ can be lots of fun. Learning something like Sage Math (http://www.sagemath.org/) might help figure things out.
- If you like simulation of physical systems, vPython has lots of possibilities (e.g. http://www.vpython.org/contents/contributed.html); or maybe Glowscript (http://www.glowscript.org/docs/GlowScriptDocs/index.html).
- If you like - as I do - experiments, then there are lots of possibilities. Here are a few examples of what I mean:
- How much corn starch do you need to add to water before a rock (or a marble) dropped onto the water will bounce? (This is the subject of a 15 April 2013 paper in the Journal of Colloid and Interface Science; or look here for a related discussion.)
- If you drop a string into a shoe box, what is the probability it will form a knot when you try to pull it out of the box. (I have left out many details. I don't know the answer, although it is closely related to a somewhat well known paper. Just google "Spontaneous knotting of an agitated string". That is a very interesting paper - done by a student - but I have always found boxes of string or cables knot even if they aren't shaken.)
- If you drop a sheet of paper, what is the probability it will end up a certain distance from its drop point? The landing distribution probably depends on the shape, size, thickness, and stiffness of the paper, the orientation and height at which it is dropped, and the friction and roughness of the surface it is landing on. There has been quite a bit of research done related to this (e.g. look here or here or here or ....), but I couldn't easily find any examples addressing this particular question.
Last updated on 6 August 2013