The Women of Fluid Mechanics: Personal Stories and Practical Advice

Last month's issue of APS News featured an article by Otani & Hu, titled "The Women of Fluid Mechanics:  Personal Stories and Practical Advice".  The article was a commentary based on a panel session at last year's annual APS Division of Fluid Dynamics (APS-DFD) meeting, which featured four female professionals in the field (3 faculty members, and the fourth the founder of a very popular blog and miniature social media empire, FYFD).  (Disclosure:  I am a "patron" of FYFD through the Patreon website.)

Among other things, the authors write that "In spite of their intellect, work ethic, and accomplishments, all of these women have faced and witnessed disrespect and scrutiny based on their gender."  It is indeed disappointing that this still happens at the end of the second decade of the 21st century.   I myself witnessed inappropriate behavior by male physics faculty in the late 1990s, as I wrote about here, though that episode was not related to fluid mechanics. 

DTLR supports efforts to reduce the barriers for women in fluid mechanics research.  One female fluid dynamicst (whom I have never met) certainly has had a key influence, through her published work, on my brief years of research in fluid mechanics.  She is cited in every fluid dynamics paper I have co-authored, and her name appears in the abstract of 3 of the 4 refereed papers of mine in the field.  Hopefully more women's names will appear in the reference lists of fluid dynamics research papers as time goes on.

Reference

Courtney Otani and David Hu, 2020:  The women of fluid mechanics:  personal stories and practical advice.  APS News, 29 (3):  8.

Feynman's 1964 Messenger Lectures

Happy New Year.  DTLR would like to point its readers to Richard Feynman's 1964 Messenger Lectures at Cornell University, which Bill Gates and Microsoft have made available for viewing at Project Tuva.  These lectures also appeared in book form (Feynman, 1967).  DTLR highly recommends this lecture series.

Reference

Richard Feynman, 1967:  The Character of Physical Law.  MIT Press.

Machine learning and fluid mechanics

Recently Physical Review Fluids published an invited op-ed, "Perspective on machine learning for advancing fluid mechanics" by Brenner, Eldredge, and Freund.  As one who has dabbled in both fields, I found their comments illuminating and balanced, conveying both astonishment and excitement at the achievements and potential of machine learning methodology, as well as its potential pitfalls and limitations.  I share their astonishment that in some cases, deep neural networks have been able to generalize beyond the training data.  This remains an ill-understood phenomenon.  We do not know under what circumstances such generalization can reliably occur, and I believe any such claims about these generalizations must be validated with independent data sets.  Regardless, however, I am in broad agreement with the authors' views, including their conclusion that machine learning methods have potential for high impact "so long as outcomes are held to the long-standing critical standards that should guide studies of flow physics."

Reference

M. P. Brenner, J. D. Eldredge, and J. B. Freund, 2019:  Perspective on machine learning for advancing fluid mecanics.  Physical Review Fluids, 4:  100501 (7 pages).

Science Magazine embraces replication (and gets its nose bloodied)

Science has put its money where its mouth is.  In this week's issue, the editor Jeremy Berg writes about "Replication Challenges".  They have published not one, but three NIH-funded replication studies of an earlier paper.  That is the good news.  The bad news is that a sister journal published a 10-patient human clinical trial, also based on the original paper, in parallel with the 3 replication studies.  Like all 3 replication studies, the human study was not able to reproduce the effect claimed in the original paper.

Can you see why journals may be reluctant to press forward with publishing replication studies?  They can certainly get their noses bloodied.  DTLR commends the editor of Science for restating his commitment to publishing replication studies.

Jerry Gollub, 1944-2019

The first substantive post I wrote for this blog, back in 2013, was a commentary on a paper of Jerry Gollub's, on continuum mechanics in physics education.  I learned recently that sadly, Dr. Gollub lost his life earlier this summer.  An obituary by his renowned collaborator, Harry Swinney, has been posted at Physics Today.  See also this obituary posted at his institution, Haverford College.  I never met or corresponded with Dr. Gollub, but his work has been an influence on mine since I was a junior in college, when I studied from his book with Gregory L. Baker, Chaotic Dynamics:  An Introduction.  In graduate school, the book he edited with Swinney, Hydrodynamic Instabilities and the Transition to Turbulence, was of equal importance to my work.  In my student days, I had these books checked out "long term" from the library, and eventually acquired copies of my own.  DTLR joins the physics and fluid mechanics communities in mourning the loss of this inspiring scientist. 

Since I completed my doctoral thesis in 2001, several other titans I cited in it have passed.  These include V. I. Arnol'd (1937-2010), Robert P. Behringer (1948-2018), Philip G. Drazin (1934-2002), Louis N. Howard (1929-2015), Daniel D. Joseph (1929-2011), Leo P. Kadanoff (1937-2015), E. Lothar Koschmieder (1929-2017), Robert Kraichnan (1928-2008), Olga Ladyzhenskaya (1922-2004), Edward N. Lorenz (1917-2008), John L. Lumley (1930-2015), Steven R. Orszag (1943-2011), William Hill Reid (1926-2016), Philip G. Saffman (1931-2008), James B. Serrin (1926-2012), and Norman J. Zabusky (1929-2018).  There may certainly be others I am not aware of.

References

G. L. Baker and  J. P. Gollub, 1996:  Chaotic Dynamics:  An Introduction.  Second edition.  New York:  Cambridge University Press.  (First edition, 1990.)

H. L. Swinney and J. P. Gollub (eds.), 1985:  Hydrodynamic Instabilities and the Transition to Turbulence.  Second edition.  Topics in Applied Physics, Vol. 45.  Berlin:  Springer.  (First edition, 1981.)

The New Yorker weighs in on statistics

Hannah Fry writes in the New Yorker this month about the benefits and pitfalls of statistics.  Highly recommended.

Reviews of Modern Physics 90th Anniversary

The February issue of Physics Today celebrates the 90th anniversary of Reviews of Modern Physics, the review journal of the American Physical Society (APS) and sibling of the Physical Review series journal DTLR has recently discussed on this blog.

Reviews of Modern Physics (RMP) has occasionally included review papers on fluid mechanics, though in an APS News post, the editor states that he wishes to expand to solicit articles on fluids.  This would be in keeping with the new Physical Review Fluids journal that recently joined the APS stable.  Of course, informed readers will know that the undisputed leading review journal in fluids is the superb Annual Review of Fluid Mechanics, founded 50 years ago (1969) this year.