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When we teach undergraduates about materials and measuring electrical resistance, we tend to gloss over the fact that there are specialized techniques for this - it's more than just hooking up a battery and an ammeter.  If you want to get high precision results, such as measuring the magnetoresistance \(\Delta R(B)\), where \(B\) is a magnetic field, to a part in \(10^{5}\) or better, more sophisticated tools are needed.  Bridge techniques compose a class of these, where instead of, say, measuring the voltage drop across a sample with a known current, instead you measure the difference between that voltage drop and the voltage drop across a known reference resistor.    Why is this good?  Well, imagine that your sample resistance is something like 1 kOhm, and you want to look for changes in that resistance on the order of 10 milliOhms.  Often we need to use relatively low currents because in condensed matter physics we are doing low temperature measurements and don't want to heat up...
8 months ago

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Updates, thoughts about industrial support of university research

Lots of news in the last few days regarding federal funding of university research: NSF has now frozen all funding for new and continuing awards.  This is not good; just how bad it is depends on the definition of "until further notice".   Here is an open letter from the NSF employees union to the basically-silent-so-far National Science Board, asking for the NSB to support the agency. Here is a grass roots SaveNSF website with good information and suggestions for action - please take a look. NSF also wants to cap indirect cost rates at 15% for higher ed institutions for new awards.  This will almost certainly generate a law suit from the AAU and others.   Speaking of the AAU, last week there was a hearing in the Massachusetts district court regarding the lawsuits about the DOE setting indirect cost rates to 15% for active and new awards.  There had already been a temporary restraining order in place nominally stopping the change; the hearing resulted in that order being extended "until a further order is issued resolving the request for a temporary injunction."  (See here, the entry for April 29.) In the meantime, the presidential budget request has come out, and if enacted it would be devastating to the science agencies.  Proposed cuts include 55% to NSF, 40% to NIH, 33% to USGS, 25% to NOAA, etc.   If these cuts went through, we are taking about more than $35B, at a rough eyeball estimate.  And here is a letter from former NSF directors and NSB chairs to the appropriators in Congress, asking them to ignore that budget request and continue to support government sponsored science and engineering research. Unsurprisingly, during these times there is a lot of talk about the need for universities to diversify their research portfolios - that is, expanding non-federally-supported ways to continue generating new knowledge, training the next generation of the technically literate workforce, and producing IP and entrepreneurial startup companies.  (Let's take it as read that it would be economically and societally desirable to continue these things, for the purposes of this post.) Philanthropy is great, and foundations do fantastic work in supporting university research, philanthropy can't come close to making up for sharp drawdowns of federal support.  The numbers just don't work.  The endowment of the Moore Foundation, for example, is around $10B, implying an annual payout of $500M or so, which is great but around 1.4% of the cuts being envisioned.   Industry seems like the only non-governmental possibility that could in principle muster the resources that could make a large-scale difference.   Consider the estimated profits (not revenues) of different industrial sectors.  The US semiconductor market had revenues last year of around $500B with an annualized net margin of around 17%, giving $85B/yr of profit.  US aerospace and defense similarly have an annual profit of around $70B.  The financial/banking sector, which has historically benefitted greatly from PhD-trained quants, has an annual net income of $250B.  I haven't even listed numbers for the energy and medical sectors, because those are challenging to parse (but large).  All of those industries have been helped greatly by university research, directly and indirectly.  It's the source of trained people.  It's the source of initial work that is too long-term for corporations to be able to support without short-time-horizon shareholders getting annoyed.  It's the source of many startup companies that sometimes grow and other times get gobbled up by bigger fish.  Encouraging greater industrial sponsorship of university research is a key challenge.  The value proposition must be made clear to both the companies and universities.  The market is unforgiving and exerts pressure to worry about the short term not the long term.  Given how Congress is functioning, it does not look like there are going to be changes to the tax code put in place that could incentivize long term investment.   Cracking this and meaningfully growing the scale of industrial support for university research could be enormously impactful.  Something to ponder.

4 days ago 1 votes
NSF, quo vadis?

There is a lot going on.  Today, some words about NSF. Yesterday Sethuraman Panchanathan, the director of the National Science Foundation, resigned 16 months before the end of his six year term.  The relevant Science article raises the possibility that this is because, as an executive branch appointee, he would effectively have to endorse the upcoming presidential budget request, which is rumored to be a 55% cut to the agency budget (from around $9B/yr to $4B/yr) and a 50% reduction in agency staffing.  (Note:  actual appropriations are set by Congress, which has ignored presidential budget requests in the past.)  This comes at the end of a week when all new awards were halted at the agency while non-agency personnel conducted "a second review" of all grants, and many active grants have been terminated.  Bear in mind, awards this year from NSF are already down 50% over last year, even without official budget cuts.  Update:  Here is Nature's reporting from earlier today. The NSF has been absolutely critical to a long list of scientific and technological advances over the last 70 years (see here while it's still up).  As mentioned previously, government support of basic research has a great return on investment for the national economy, and it's a tiny fraction of government spending.  Less than three years ago, the CHIPS & Science Act was passed with supposed bipartisan support in Congress, authorizing the doubling of the NSF budget.  Last summer I posted in frustration that this support seemed to be an illusion when it came to actual funding.   People can have disagreements about the "right" level of government support for science in times of fiscal challenges, but as far as I can tell, no one (including and especially Congress so far) voted for the dismantling of the NSF.  If you think the present trajectory is wrong, contact your legislators and make your voices heard.

2 weeks ago 1 votes
A Grand Bargain and its chaotic dissolution

After World War II, under the influence (direct and indirect) of people like Vannevar Bush, a "grand bargain" was effectively struck between the US government and the nation's universities.  The war had demonstrated how important science and engineering research could be, through the Manhattan Project and the development of radar, among other things.  University researchers had effectively and sometimes literally been conscripted into the war effort.  In the postwar period, with more citizens than ever going to college because of the GI Bill, universities went through a period of rapid growth, and the government began funding research at universities on the large scale.  This was a way of accomplishing multiple goals.  This funding got hundreds of scientists and engineers to work on projects that advisors and the academic community itself (through peer review) thought would be important but perhaps were of such long-term or indirect economic impact that industry would be unlikely to support them.  It trained the next generation of researchers and of the technically skilled workforce.  It accomplished this as a complement to national laboratories and direct federal agency work. After Sputnik, there was an enormous ramp-up of investment.  This figure (see here for an interactive version) shows different contributions to investment in research and development in the US from 1953 through 2021: Figure from NSF report on US R&D investment  A couple of days ago, the New York Times published a related figure, showing the growth in dollars of total federal funds sent to US universities, but I think this is a more meaningful graph (hat tip to Prof. Elizabeth Popp Berman at Michigan for her discussion of this).  In 2021, federal investment in research (the large majority of which is happening at universities) as a percentage of GDP was at its lowest level since 1953, and it was sinking further even before this year (for those worried about US competitiveness....  Also, industry does a lot more D than they do long-term R.). There are many studies by economists showing that federal investment in research has a large return (for example, here is one by the Federal Reserve Bank of Dallas saying that returns to the US economy on federal research expenditures are between 150% and 300%).  Remember, these funds are not just given to universities - they are in the form of grants and contracts, for which specific work is done and reported.   These investments also helped make US higher education the envy of much of the world and led to education of international students as a tremendous effective export business for the country. Of course, like any system created organically by people, there are problems.  Universities are complicated and full of (ugh) academics.  Higher education is too expensive.  Compliance bureaucracy can be onerous.  Any deliberative process like peer review trades efficiency for collective expertise but also the hazards of group-think.  At the same time, the relationship between federally sponsored research and universities has led to an enormous amount of economic, technological, and medical benefit over the last 70 years. Right now it looks like this whole apparatus is being radically altered, if not dismantled in part or in whole.  Moreover, this is not happening as a result of a debate or discussion about the proper role and scale of federal spending at universities, or an in-depth look at the flaws and benefits of the historically developed research ecosystem.  It's happening because "elections have consequences", and I'd be willing to bet that very very few people in the electorate cast their votes even secondarily because of this topic.   Sincere people can have differing opinions about these issues, but decisions of such consequence and magnitude should not be taken lightly or incidentally.   (I am turning off comments on this one b/c I don't have time right now to pay close attention.  Take it as read that some people would comment that US spending must be cut back and that this is a consequence.)

2 weeks ago 13 votes
Talk about "The Direct Democracy of Matter"

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.

3 weeks ago 10 votes
US science situation updates and what's on deck

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.)

3 weeks ago 13 votes

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