The Scientia Institute at Rice sponsors series of public lectures annually, centered around a theme.  The intent is to get a wide variety of perspectives spanning across the humanities, social sciences, arts, sciences, and engineering, presented in an accessible way.  The youtube channel with recordings of recent talks is here. This past year, the theme was "democracy" in its broadest sense.  I was honored to be invited last year to contribute a talk, which I gave this past Tuesday, following a presentation by my CS colleague Rodrigo Ferreira about whether AI has politics.  Below I've embedded the video, with the start time set where I begin (27:00, so you can rewind to see Rodrigo).   Which (macroscopic) states of matter to we see?  The ones that "win the popular vote" of the microscopic configurations.

Many things have been happening in and around US science.  This is a non-exhaustive list of recent developments and links: There have been very large scale personnel cuts across HHS, FDA, CDC, NIH - see here.  This includes groups like the people who monitor lead in drinking water.   There is reporting about the upcoming presidential budget requests about NASA and NOAA.  The requested cuts are very deep.  To quote Eric Berger's article linked above, for the science part of NASA, "Among the proposals were: A two-thirds cut to astrophysics, down to $487 million; a greater than two-thirds cut to heliophysics, down to $455 million; a greater than 50 percent cut to Earth science, down to $1.033 billion; and a 30 percent cut to Planetary science, down to $1.929 billion."  The proposed cuts to NOAA are similarly deep, seeking to end climate study in the agency, as Science puts it. The full presidential budget request, including NSF, DOE, NIST, etc. is still to come.  Remember, Congress in the past has often essentially ignored presidential budget requests.  It is unclear if the will exists to do so now.  Speaking of NSF, the graduate research fellowship program award announcements for this year came out this past week.  The agency awarded slightly under half as many of these prestigious 3-year fellowships as in each of the last 15 years.  I can only presume that this is because the agency is deeply concerned about its budgets for the next couple of fiscal years. Grants are being frozen at several top private universities - these include Columbia (new cancellations), the University of Pennsylvania (here), Harvard (here), Northwestern and Cornell (here), and Princeton (here).  There are various law suits filed about all of these.  Princeton and Harvard have been borrowing money (issuing bonds) to partly deal with the disruption as litigation continues.  The president of Princeton has been more vocal than many about this. There has been a surge in visa revocations and unannounced student status changes in SEVIS for international students in the US.  To say that this is unsettling is an enormous understatement.  See here for a limited discussion.  There seems to be deep reluctance for universities to speak out about this, presumably from the worry that saying the wrong thing will end up placing their international students and scholars at greater exposure. On Friday evening, the US Department of Energy put out a "policy flash", stating that indirect cost rates on its grants would be cut immediately to 15%.  This sounds familiar.  Legal challenges are undoubtedly beginning.   Added bonus:  According to the Washington Post, DOGE (whatever they say they are this week) is now in control of grants.gov, the website that posts funding opportunities.  As the article says, "Now the responsibility of posting these grant opportunities is poised to rest with DOGE — and if its employees delay those postings or stop them altogether, 'it could effectively shut down federal-grant making,' said one federal official who spoke on the condition of anonymity to describe internal operations."   None of this is good news for the future of science and engineering research in the US.  If you are a US voter and you think that university-based research is important, I encourage you to contact your legislators and make your opinions heard.   (As I have put in my profile, what I write here are my personal opinions; I am not in any way speaking for my employer.  That should be obvious, but it never hurts to state it explicitly.)

(A post summarizing recent US science-related events will be coming later.  For now, here is my promised post about multiferroics, inspired in part by a recent visit to Rice by Yoshi Tokura.) Electrons carry spins and therefore magnetic moments (that is, they can act in some ways like little bar magnets), and as I was teaching undergrads this past week, under certain conditions some of the electrons in a material can spontaneously develop long-range magnetic order.  That is, rather than being, on average, randomly oriented, instead below some critical temperature the spins take on a pattern that repeats throughout the material.  In the ordered state, if you know the arrangement of spins in one (magnetic) unit cell of the material, that pattern is repeated over many (perhaps all, if the system is a single domain) the unit cells.  In picking out this pattern, the overall symmetry of the material is lowered compared to the non-ordered state.  (There can be local moment magnets, when the electrons with the magnetic moments are localized to particular atoms; there can also be itinerant magnets, when the mobile electrons in a metal take on a net spin polarization.)  The most famous kind of magnetic order is ferromagnetism, when the magnetic moments spontaneously align along a particular direction, often leading to magnetic fields projected out of the material.    Magnetic materials can be metals, semiconductors, or insulators. In insulators, an additional kind of order is possible, based on electric polarization, \(\mathbf{P}\).  There is subtlety about defining polarization, but for the purposes of this discussion, the question is whether the atoms within each unit cell bond appropriately and are displaced below some critical temperature to create a net electric dipole moment, leading to ferroelectricity.  (Antiferroelectricity is also possible.) Again, the ordered state has lower symmetry than the non-ordered state.  Ferroelectric materials have some interesting applications.   BiFeO3, a multiferroic antiferromagnet, image from here. Multiferroics are materials that have simultaneous magnetic order and electric polarization order.  A good recent review is here.  For applications, obviously it would be convenient if both the magnetic and polarization ordering happened well above room temperature.  There can be deep connections between the magnetic order and the electric polarization - see this paper, and this commentary.   Because of these connections, the low energy excitations of multiferroics can be really complicated, like electromagnons.  Similarly, there can be combined "spin textures" and polarization textures in such materials - see here and here.   Multiferroics raise the possibility of using applied voltages (and hence electric fields) to flip \(\mathbf{P}\), and thus toggle around \(\mathbf{M}\).  This has been proposed as a key enabling capability for information processing devices, as in this approach.  These materials are extremely rich, and it feels like their full potential has not yet been realized.

Here are a couple of neat papers that I came across in the last week.  (Planning to write something about multiferroics as well, once I have a bit of time.) The idea of directly extracting useful energy from the rotation of the earth sounds like something out of an H. G. Wells novel.  At a rough estimate (and it's impressive to me that AI tools are now able to provide a convincing step-by-step calculation of this; I tried w/ gemini.google.com) the rotational kinetic energy of the earth is about \(2.6 \times 10^{29}\) J.  The tricky bit is, how do you get at it?  You might imagine constructing some kind of big space-based pick-up coil and getting some inductive voltage generation as the earth rotates its magnetic field past the coil.  Intuitively, though, it seems like while sitting on the (rotating) earth, you should in some sense be comoving with respect to the local magnetic field, so it shouldn't be possible to do anything clever that way.  It turns out, though, that Lorentz forces still apply when moving a wire through the axially symmetric parts of the earth's field.  This has some conceptual contact with Faraday's dc electric generator.   With the right choice of geometry and materials, it is possible to use such an approach to extract some (tiny at the moment) power.  For the theory proposal, see here.  For an experimental demonstration, using thermoelectric effects as a way to measure this (and confirm that the orientation of the cylindrical shell has the expected effect), see here.  I need to read this more closely to decide if I really understand the nuances of how it works. On a completely different note, this paper came out on Friday.  (Full disclosure:  The PI is my former postdoc and the second author was one of my students.)  It's an impressive technical achievement.  We are used to the fact that usually macroscopic objects don't show signatures of quantum interference.  Inelastic interactions of the object with its environment effectively suppress quantum interference effects on some time scale (and therefore some distance scale).  Small molecules are expected to still show electronic quantum effects at room temperature, since they are tiny and their electronic levels are widely spaced, and here is a review of what this could do in electronic measurements.  Quantum interference effects should also be possible in molecular vibrations at room temperature, and they could manifest themselves through the vibrational thermal conduction through single molecules, as considered theoretically here.  This experimental paper does a bridge measurement to compare the thermal transport between a single-molecule-containing junction between a tip and a surface, and an empty (farther spaced) twin tip-surface geometry.  They argue that they see differences between two kinds of molecules that originate from such quantum interference effects. As for more global issues about the US research climate, there will be more announcements soon about reductions in force and the forthcoming presidential budget request.  (Here is an online petition regarding the plan to shutter the NIST atomic spectroscopy group.)  Please pay attention to these issues, and if you're a US citizen, I urge you to contact your legislators and make your voice heard.