2020-08-10

Eighth, Ninth, Tenth, and Eleventh Papers

My eighth, ninth, tenth, and eleventh papers have been published! These require subscriptions to read, so here are alternate links to older preprints for the eighth, ninth, tenth, and eleventh papers, respectively (which have most of the same content, with some minor changes to explanations, citations, and figures relative to the published versions). As with my previous papers, in the interest of explaining these ideas in a way that is easy to understand, I am using the ten hundred most used words in English (except for the two lines that came before this one), as put together from the XKCD Simple Writer. I will use numbers sometimes without completely writing them out, use words for certain names of things without explaining further, and explain less used words when they come up. Keep reading to see what comes next. While these papers aren't as closely related to each other as the previous three, there are enough relations that I'm putting them together in a single post. These papers need a lot more math (note: "math" isn't one of the ten hundred words) than the papers before, and because they need a lot of thinking to get, I actually won't say as much about them.

On another note, this is a milestone for me because these are the last papers from my PhD in which I was a leading author. I still have one more review paper left to be published, but as that has been submitted to the journal and as I'm not the leading author, I don't really need to worry about that at this point. (Of course, once that is published, I will write a blog post summarizing it, though as it is a review paper, that summary will probably be quite short.) Thus, I am truly done with the work from my PhD, and can fully shift my mindset away from physics toward thinking about problems in transportation policy, as I will do in my postdoctoral research at UC Davis.

2020-08-03

Book Review: "The Worldly Philosophers" by Robert L. Heilbroner

I've recently read the book The Worldly Philosophers by Robert L. Heilbroner; this was a book that I got from a friend who moved away a few years ago, but never got around to reading until now. This book is essentially a survey of the lives & works of famous philosophers whose works & thoughts had fundamental impacts on the development of economics as a field, and who considered the general problems faced by & ultimate evolution of society to be within the purview of their grand theories. The preface gives some background regarding the writing of this book, the first chapter explains how economic philosophy can be especially dangerous as it has arguably much more immediate relevance to human society but much less rigorous testability than natural sciences, the second chapter explains why economics as a distinct discipline did not emerge until societal change in Europe (and its colonies in North America) had led to a state where the interconnections of goods, services, and money pervaded all aspects of life even for ordinary people (i.e. going far beyond the raising of stocks & bonds for the large colonial corporations like the Dutch East India Company, which had to deal with financial instruments only at the level of the national interest), the eleventh (final) chapter recapitulates the ideas of the book and explains that there may be no further grand theorists of "worldly philosophy" because the apparent inability of capitalism to effectively regulate itself (in the author's view, at the time of the publication of this edition in 1986) would mean all further development would have to come more from active political decisionmaking, and each chapter in between catalogs the lives & works of famous "worldly philosophers". A key feature of this book is that the historical context of each of these philosophers' lives is made clear, such that the development of those philosophies can be read as essentially a natural consequence of those circumstances; as examples, the optimism of Adam Smith is seen as coming from his observation of improved standards of living arising from the proliferation of many small factories, while the pessimism of Thomas Malthus & David Ricardo came from their observations of growing numbers of people living in abject poverty and in unsafe & overcrowded conditions without their living standards seeming to improve as a whole.

The book is written in a very engaging, accessible, and clear way. The details of the philosophers' lives make for a more interesting read, and they sometimes (though not always) even add further context for understanding how the mindsets behind their philosophies. Moreover, the author's contextualization of each philosophy in its historical place & time is combined with clear explanations of the more generally applicable features of those philosophies, so that it becomes clear whether certain aspects of some philosophies that are dependent on the historical contexts leading to their development might suggest that applying those philosophies today may be problematic. This is also combined with cogent & clear critical analysis of those philosophies in the present context by the author, as appropriate; perhaps there could have been a little more critical analysis of some of the assumptions of Karl Marx, and I felt like the author made John Maynard Keynes's analysis of the emergence of economic recessions from savings gluts seem unduly different from prior ideas that economic recessions are essentially mass panics, but these are ultimately minor points. (As "present" means 34 years ago, some of those analyses & predictions have obviously not aged well, but in fairness, I cannot hold that against the author, because none of those analyses suggest an arrogance on the part of the author in claiming that nothing of those analyses would change 34 years later.)

The explanations of the various philosophies aren't extremely deep, but they are deep enough to give readers an appreciation for their contexts & differences and to encourage readers to learn more. For instance, I was struck by realizing how similar my thoughts about economic policy are to those of John Stuart Mill, so I've been inspired to read more by & about him. As another example, I always felt too intimidated to read about Karl Marx, due to the high likelihood that what I would find online would be too inflammatory/partisan (as he is revered among socialists & communists and reviled among many other groups, especially in the US given the country's historically strong anticommunist stance); while I may be biased in my sensibilities from growing up in the US, I thought the author did a good job of treating Marx & his work in an evenhanded way, explicitly stating that Marx should be thought of as neither saint nor demon, and the same should be true of his work. I also thought that by the end of the book, the reasons for the author's choices of which philosophers to highlight became quite clear. For example, I wondered why Henry George wasn't discussed in a full chapter but only in a part, but then the author made clear that this is partly because Henry George's singular focus on land rents was overly narrow & simplified, and because Henry George, like other heterodox economists in the 19th century, was too uncritically revered by those who wanted to think about the deep implications of economics for society (as opposed to the narrow focuses on mathematical formalism & description of equilibrium that had come into favor among establishment orthodox economists at that time); the author's criticisms helped to solidify some of the instinctive reservations that I had but couldn't quite articulate about Henry George's claims that taxing only land & rents would solve everything, as it seemed intuitively appealing yet weirdly incomplete. As another example, I felt like the chapter on Joseph Schumpeter didn't seem to suggest any great impact that would justify his inclusion along with John Maynard Keynes or other philosophers, but the following (final) chapter made clear that the real novelty of Schumpeter's analysis was in predicting an end state for business owners/capitalists that was notably different from their beginning state, and using this to argue for socialism as an end state to capitalism for completely different reasons than what Marx argued. Perhaps it could be argued that the contributions of John von Neumann & John Nash to game theory merited further discussion, given the important application of game theory to international politics (particularly nuclear deterrence in the Cold War), but a counterargument would be that unlike those discussed in this book, they did not set forth grand economic philosophies describing society as a whole, nor did they broadly set out to describe the evolution or endpoint of capitalism.

Overall, I rather enjoyed reading this book. I would recommend it to anyone who is interested in starting to learn about economic philosophies, as the engaging storytelling helps to leaven the philosophical parts that may seem drier to some readers.

2020-07-01

Classical Phase Space Densities for One or a Few Particles

This is the first time in several years that I've done a post about physics that didn't have to do with my research. This came about from thinking about applying techniques in statistical physics to game theory; although I still have a lot more to learn about that and need to do more to flesh out those ideas, it occurred to me in the process that I never had such a good intuition for the phase space density in classical mechanics, and notes that I've found online focus almost exclusively on the phase space density of a large number of particles in an explicitly statistical treatment. I intend to use this post to shed light on why this may be the case, help build intuition for how things like the Liouville equation work for simple systems of one or a few particles, and reinforce the notion that there is no classical analogue to the phenomenon of a multi-particle entangled quantum state yielding a mixed single-particle state under a partial trace. Follow the jump to see more.

2020-06-23

Book Review: "The Social Contract" by Jean-Jacques Rousseau

Now that I have been able to properly enjoy the summer, having essentially finished my PhD work, I've recently read the book The Social Contract by Jean-Jacques Rousseau (translated from French to English by Willmoore Kendall); this was a book that I got from a friend who moved away a few years ago, but never got around to reading until now. This is one of the classic texts of political philosophy from the European Enlightenment era, and came before many of the seminal events of world history, including the American & French Revolutions and the European colonization & subsequent independence of much of Asia, Africa, Australia, and South America. The author provides his own refutations of many of the arguments for hereditary monarchy and instead forcefully argues for a legislature, separate from the executive, that is conducted as a direct democracy, even while acknowledging that different circumstances for different states may suggest different forms & sizes for the executive. The book includes many examples from ancient & medieval European history, and while much of the discussion of cultures outside of Europe seems antiquated or racist to modern eyes, I imagine it was typical of its time & place.

It was really interesting to see such broad imagination of democratic & republican societies before they came to be in Europe & North America. However, the book itself is not an easy read: it basically feels like a polemical political treatise written in the terse style of the textbooks by the physicists Landau & Lifshitz, in which every definition and proposition must be carefully parsed & understood individually and also as part of a broader whole. The arguments are built up slowly, so patience is required too; frequently, I found myself wondering how the author could fail to acknowledge certain seemingly-elementary rebuttals to his arguments, only to find such acknowledgments after several pages. Originally, I thought the translator's introduction about how to read the book were basically excuses meant to cover for bad writing, but as I read through more of the book, I came to appreciate it more.

There are a few comments that I have about the contents. The first is that it isn't clear to me how citizens, in the author's view, are supposed to resume the exercise of natural rights, which have been pooled into the sovereign & redistributed as civil rights, when the social contract is thought to be violated, especially as it also isn't clear to me how to distinguish a violation of the social contract from an individual's unhappiness with the general will going against that individual's private will. Related to this, it isn't clear to me how a citizen, acting to debate & make laws for the sovereign to further the general will, is supposed to act completely separately, as a sort of Jekyll/Hyde situation, from that person's thoughts as an individual, because the execution of laws furthering the general will may affect that individual and others perhaps not particularly naming those people but naming a certain group affiliation, and it becomes hard then to define the general will in that context. The second is that so many of the author's arguments regarding the formation of a new state seem to depend on their being a full vacuum of power beforehand, with only the barest acknowledgment that new societies & nations don't emerge from a vacuum; to be fair, many of the great upheavals that figure prominently in my imagination regarding this point came after the publication of this book, but enough had happened which the author mentioned that this sparing treatment of the issue seems odd. I also have some more minor comments, namely that I'm not sure if the author's specific claims about the intertwined nature of politics & religion in ancient societies would be validated by modern scholarship, and the author's claims about there being no "true" Christian soldiers seems to rely too much on a no-true-Scotsman fallacy.

I would certainly need to reread this book carefully to better appreciate it, and perhaps that could address at least some of my comments. In any case, I'd only recommend this book to people with a serious deeply-rooted interest in political philosophy, who can appreciate the book and the context of its time & place, as opposed to novices like myself.

2020-05-28

Reflection: My Graduate Experiences at Princeton University

Please note: there will be mentions of the current global public health crisis in this post. I have no background in medicine, public health, or closely-related fields. Please consult public health agencies and other governmental agencies for guidance regarding responses to this crisis, and please consult actual professionals as appropriate for individual problems in this context.

This post is the third in a series of three posts about the end of my time as a PhD student in Princeton University (in this post henceforth referred to simply as "the university" when there is no ambiguity). As a write this, I have successfully defended my PhD thesis! Furthermore, I will officially be graduating this coming weekend. This post follows the first, which was meant as a reflection of the events of this public health crisis that led to my premature physical departure from the university campus combined with a paean to the friends I made over the course of 6 years in the PhD program, and the second, which explained the experiences & thought processes that led to my decision to change careers from research in physics to transportation policy. This post is a broader reflection of my time and experiences at the university, with all of its ups and downs, and a message of gratitude toward the people in the university and elsewhere who meant so much to me during my time in the program; a lot of it is taken from the acknowledgments in my thesis, though for privacy reasons, I won't be giving explicit names. Additionally, there will undoubtedly be many comparisons over the course of this post to my undergraduate experiences at MIT, for which I wrote a post around the time of graduation 6 years ago. Follow the jump to see more.

2020-04-28

Reflection: Starting a Shift to a New Career in Transportation Policy

This post is the second in a series of three posts about the end of my time as a PhD student in Princeton University (in this post henceforth referred to simply as "the university"). As a write this, I am still technically a PhD student enrolled full-time in the university, working on topics in nanophotonics & fluctuational electromagnetics. Next fall (assuming the current public health crisis abates to an extent that it is safe for me to do so — please note that I am not a public health expert or epidemiologist, so I am not making predictions in this regard), however, I will start a postdoctoral research position in the University of California Davis analyzing transportation policy, with a particular eye toward the effects of such current & future policies on the mobility and resulting socioeconomic opportunities for those who have been marginalized by current transportation systems, including people who are poor or have disabilities (like myself). This is a fairly drastic, and arguably surprising, change of career; I have told many friends and relatives about this, but not all of them, so I'd like to use this space to explain my thought process over the years leading up to this decision. Follow the jump to see more.

2020-03-17

Reflection: A Week of Downward-Spiraling Public Health News Culminating in Unexpected Adjustments

Please note: this is about the current widespread disease outbreak that is dominating the news. I will not mention the name of this disease or other common words used to describe its spread, because for good reason, popular search engines are cracking down on articles and videos other than those from official public health agencies and related well-established organizations to stop the spread of misinformation. I have no background in epidemiology or public health. This post is merely my musings about the last week, and the implications for my near-future plans. Please consult public health agencies and other governmental agencies for guidance regarding responses to this crisis.

This post is the first in a series of three posts about the end of my time as a PhD student in Princeton University (in this post henceforth referred to simply as "the university"). As a write this, I am still technically a PhD student enrolled full-time in the university. The second and third posts will be somewhat more traditional reflections for the end of my time, but this first one has been precipitated by the current public health crisis. Follow the jump to see more; it is effectively a chronological history of the developments of this crisis from my very narrow perspective, and my own (in hindsight, arguably delusional) reactions to these developments.

2020-02-03

Book Review: "Michael Polanyi" by Mark T. Mitchell

I've recently read the book Michael Polanyi by Mark T. Mitchell. (As an aside, it may be worth noting that some listings of this book carry the subtitle The Art of Knowing, but the usage of this subtitle within the copy of the book I got was inconsistent.) The book gives a relatively brief summary of the life and times of the physical chemist-turned-economist/philosopher Michael Polanyi in the first chapter, and then goes into a little more detail about his philosophies on economics, politics, science, morality, knowledge, religion, and other things in the second through fourth chapters, concluding in the fifth chapter with a comparison of his philosophical views to those of his contemporaries along with a little discussion about the implications of Polanyi's views for the present day.

The book is fairly short, well-written, and engaging even for a layperson like myself. The overview of Polanyi's life is quite interesting, and as I am considering the next steps for my own career (more on that in a future post), I was particularly taken by the story of Polanyi's career change so late in life. The discussion of his philosophy avoids unexplained jargon and very heavy technical arguments, instead clearly laying things out in simple terms & examples, and I was surprised (mainly as I was previously unacquainted with Polanyi's work per se, even though I have already read works about some of the people who influenced him and whom he may have influenced) to see myself having come to similar conclusions as Polanyi even before reading this book. With respect to the latter point, though, I do have a few criticisms, which are attributable in parts to Polanyi or to the author of this book. For one, the appeals to common sense & simple examples lead to the situation where the defense of Polanyi's theory of tacit knowledge against charges of subjectivism or circularity (i.e. begging the question) isn't necessarily as tightly constructed or satisfying as possible; some of this comes from Polanyi's own quotes, while the remainder comes from the author (who seems to agree with and follow Polanyi's philosophy). For another, some of Polanyi's defenses of Christianity and critiques of evolutionary theory, with respect to their implications for constructing meaning out of human existence, aren't clear as to how broadly they should be applied in his more general framework, and it isn't clear whether this very opacity is in itself the fault of Polanyi versus the author of this book. Overall, I really enjoyed reading this book, and would recommend it to anyone looking for a nontechnical clear read about a sometimes-overlooked figure in Western philosophy of the 20th century. Follow the jump to read more detailed summaries per chapter and about my thoughts regarding the book as well as Polanyi's philosophy (warning: it may be quite roughly organized).

2020-01-13

Fifth, Sixth, and Seventh Papers

My fifth, sixth, and seventh papers have been published! These require subscriptions to read, so here are alternate links to older preprints for the fifth, sixth, and seventh papers, respectively (which have most of the same content, with some minor changes to explanations, citations, and figures relative to the published versions). As with my previous papers, in the interest of explaining these ideas in a way that is easy to understand, I am using the ten hundred most used words in English (except for the two lines that came before this one), as put together from the XKCD Simple Writer. I will use numbers sometimes without completely writing them out, use words for certain names of things without explaining further, and explain less used words when they come up. Keep reading to see what comes next. I'm putting these three papers together in a single post because they form a trilogy of sorts, all having to do with finding the biggest number for how much heat, through light, can go from one body to another when they are really close together, or can go from one body into outer space. These papers need a lot more math (note: "math" isn't one of the ten hundred words) than the papers before, and because they need a lot of thinking to get, I actually won't say as much about them.

The fifth paper is called "T Operator Bounds on Angle-Integrated Absorption and Thermal Radiation for Arbitrary Objects", and is in volume 123, issue 5 of Physical Review Letters. This is the one that has to do with how much heat, through light, can go from one body to outer space. People knew before that the number for how much heat really big bodies can put through light into outer space grows like the surface area of the body, but for really small bodies it grows like the space of the whole body (volume), and they were not sure how these two things join in between. This paper lets people figure out what the most heat is that can go from a body through light into outer space no matter what the largest shape the body can sit in, and shows how to join the things that people knew before for middle-size bodies of different shapes. (Another press release from my department can be found here.)

The sixth paper is called "Fundamental limits to radiative heat transfer: Theory", and is in volume 101, issue 3 of Physical Review B, while the seventh paper is called "Fundamental Limits to Radiative Heat Transfer: The Limited Role of Nanostructuring in the Near-Field", and is in volume 124, issue 1 of Physical Review Letters. Those two papers go together, so I'll write about them together. The sixth paper is about the math behind figuring out the biggest number for heat, through light, to go between two bodies. The seventh paper shows that heat, through light, going between two big flat bodies that are close together can be pretty close to the biggest number possible, so making the shapes of the bodies less simple than just flat surfaces is of no use.

2019-12-20

My Time at the STEPS+ 2019 Fall Symposium

Last week, I attended the STEPS+ 2019 Fall Symposium, hosted at UC Davis. (I'll have more details about the broader reasons for the trip in an upcoming post). It was a nice set of talks and open discussions about energy issues in transportation, as well as a good opportunity for professional networking. Much of the discussion was focused on California because its large geographic & demographic size, the fact that its own metropolitan areas have minimal spillover into other states and vice versa, and the clear separation of powers between the state and local governments means that it can effectively operate like an autonomous country in miniature (evidenced also by its own large population and economic output). That said, the diverse range of political interests, geographic features, and climates in the state make it to some extent a microcosm of what would need to happen at the national level too with respect to combating climate change, decarbonizing the economy, and making transportation generally more sustainable. Thus, although my interests tend more toward the direct relationship between transportation and issues of socioeconomic equity, there are strong indirect relationships through energy and climate issues too, so it was really interesting to learn about these, to learn more about communication between researchers and policymakers, and to see what models exist for working toward greater sustainability in transportation.