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Is relativity a dead field?

  1. Nov 21, 2013 #1
    Undergrad here. I'm filling out grad school apps and my BIG interest is GR, most likely numerical relativity.

    But I have heard that this is a dead field, that professors working in it don't take on new students, etc.

    But it's the reason I'm in physics in the first place. I'm applying to schools that all have active relativity/gravity groups and most of which do numerical relativity.

    What is your opinion?
     
    Last edited: Nov 21, 2013
  2. jcsd
  3. Nov 21, 2013 #2

    ZapperZ

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    The last time someone declared a subject area in physics to be "dead", it was superconductivity pre-1985. We all now know how all hell broke loose after that!

    Considering that they're spending money on LISA/LIGO/etc., and the Dark Energy Survey project, I would not consider this topic to be "dead" at all!

    Zz.
     
  4. Nov 21, 2013 #3

    WannabeNewton

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    The term "dead field" only has meaning relative to the prominence of other fields of physics. If you are speaking of classical GR then it is not at all inaccurate to say that it is a "dead field" but the phrase "dead field" is an uncharacteristically strong one. As a standalone subject its sustenance comes from cosmology, numerical relativity, and the philosophy of general relativity all of which tend to be very small departments compared to those of other major fields of physics. Are there active departments working on cosmology, numerical relativity, and/or the philosophy of general relativity? Sure. Are they big? Usually not.

    Using my own physics department as an example, take a look at the size of the general relativity department (http://www.physics.cornell.edu/research/astrophysics-and-general-relativity/) and compare it to the size of the condensed matter theory department (http://www.physics.cornell.edu/research/theoretical-condensed-matter-physics/) and that of theoretical particle physics (http://www.physics.cornell.edu/research/theoretical-elementary-particle-physics/). Experimental speaks for itself.

    Also take a look at UChicago's general relativity department (http://physics.uchicago.edu/research/areas/general_relativity.html [Broken])

    By the way, if you look at the history of developments in general relativity it should come as no surprise that classical general relativity is a "dead field" at this point in time in the sense that it is more or less fleshed out (compare this to QFT for example). Open problems on the theoretical side involving general relativity tend to be more related to mathematical physics, in particular PDE theory. On the experimental side there are a slew of cosmological problems (e.g. gravitational wave detection) that rely heavily on general relativity.

    Good luck with your applications!
     
    Last edited by a moderator: May 6, 2017
  5. Nov 26, 2013 #4
    By "numerical relativity" do you mean numerical solution of PDE's? If so, why do you *have to* solve PDEs that emerge from GR theory? You might end up solving the same PDE that someone next door in civil engineering is trying to solve. Why do you *need* to stick to the interest that got you into physics?

    Not trying to pour water on your parade here, just suggesting you do some lateral thinking in case you can't get into a GR school. If you're at all capable, I'm sure you'll be able to get into *some* school that requires numerical solution of PDEs. (And when you have tenure in the School of Mathematical Physics, you can apply your vast knowledge of solving PDEs to some examples emanating from the field of GR...)
     
  6. Nov 26, 2013 #5
    My professor just went over a list of unsolved problems in GR, and several remain open, with one being particularly nasty (the Big Bang singularity problem), and others less so (the inflationary hypothesis seems to account for a lot of the big problems like monopoles or fluctuations). There are numerous famous problems at the intersection of QFT and GR, such as the vacuum catastrophe. Discussing this with my professor, his opinion (for what it's worth) is that new physics is needed; so if you're ONLY interested in GR, I'm not sure what problems solely deal with that topic; this is just my own fairly freshly created point of view though.

    But getting into a prestigious school to work on such problems is no cake walk; even my school which is not very famous receives more applicants for cosmology/GR than it can admit, by quite a bit. That said, look at less famous schools and see what the professors are up to; my institution, for instance, has recently hired several theorists and appropriated a large budget to cosmology/astrophysics, so if this is really interesting it may be possible to study it here or other more lowly ranked institutions. You'll most likely wind up outside academia anyway from what I've been told, so the only important thing is to ask where the graduate students wound up to see if the advisors have any connections (a friend of mine working at Columbia under a popularly famous advisor is lined up with a high paying finance job, but I don't know if you have any shot at such opportunities if you're at University of Nowhere).
     
  7. Nov 26, 2013 #6

    WannabeNewton

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    Yep this was my point as well and I must agree with you on this for the most part. There are open problems in cosmology (both experimental and theoretical) that would rely solely on classical GR but at some point there is an interface with non-classical theories that can't be avoided. Also, there are some open problems in mathematical relativity but I don't know if that counts as physics seeing as the problems tend to be purely mathematical in nature; if you're interested you can peruse through Choquet-Bruhat (2009). There is also the study of the conceptual and mathematical foundations of GR (which is an extremely interesting subject matter in my opinion) but such a study is arguably more on the side of philosophy of physics.
     
  8. Nov 26, 2013 #7
    If you're really determined to get a job in academia, my impression (it's just an impression) is that math departments tend to be bigger since there is a greater demand for math teachers; so if mathematical physics appeals to you, that might not be a bad idea. Just be prepared to accept a lecturing position with more teaching responsibilities (which sounds like a nice job, except for the lack of benefits and low pay).
     
  9. Nov 26, 2013 #8

    George Jones

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    It seems that numerical GR is an active area of research, though I don't know how big the area is.

    For example, in the near future (LIGO and maybe LISA), we hope to extract useful physical information from the gravitation radiation signal form black hole mergers. In order to do this, we have to have theoretical predictions from GR on what this signal should look like. This was only accomplished in that last decade using numerical GR.

    Three recent advanced texts:

    1) "Numerical Relativity: Solving Einstein's Equations on the Computer" by Baumgarte and Shapiro (2010),
    https://www.amazon.com/Numerical-Re...uations-Computer/dp/052151407X/ref=pd_sim_b_2

    2) "Introduction to 3+1 Numerical Relativity" by Alucbierre (2012),
    https://www.amazon.com/Introduction...ional-Monographs/dp/0199656150/ref=pd_sim_b_1

    3) "3+1 Formalism in General Relativity: Bases of Numerical Relativity" by Eric Gourgoulhon (2012),
    https://www.amazon.com/Formalism-General-Relativity-Numerical-Lecture/dp/3642245242/ref=pd_sim_b_3

    From the back cover of 1): "Aimed at students and researchers entering the field ..."

    From the back cover of 2): "This book is aimed at both graduate students and researchers in physics and astrophysics"

    From the back cover of 3): "This graduate-level, course-based text is devoted to the 3+1 formalism of general relativity, which also constitutes the theoretical foundations of numerical relativity"
     
  10. Nov 26, 2013 #9

    George Jones

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    I am not sure what happens at universities in other countries, but, in Canada, there are permanent instructor and lecturer positions that are faculty positions, with same benefits as any other faculty position, and with okay to good pay.

    For example, I am an instructor at a small Canadian university. Last year I had extensive dental work done, most of it paid for by the university.

    These permanent positions, however, are not that easy to get.
     
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