Brooklyn Is Not Expanding

By Sean Carroll | September 10, 2007 11:56 am

I referred to this scene from Annie Hall in my talk yesterday. A classic.

“Something he read.” That’s always the problem, isn’t it?

(Note that everyone seems to be buying into some sort of Big Rip cosmology. It makes for a more vivid eschatology.)

  • Jonathan Vos Post

    “Ah, the Brain,” said Woody Allen. “My second favorite organ.”

  • rudy mcgoody

    why are audio and video so often out of sync on youtube? or is it something my end?

  • senderista

    I think Woody’s mom meant by “Brooklyn is not expanding” something like “the cosmological expansion does not apply to gravitationally bound systems like Brooklyn”.

  • Moshe

    High power cosmological theories notwithstanding, it is the useless counselor that makes the scene for me, it is amazing how much (wrong) attitude can be packed into one simple sentence.

  • Paul Stankus

    What I like best in the Annie Hall clip is that Alvy is more worried about the expansion of the Universe than he is about the fact that his doctor smokes.

    It’s a natural for an intro cosmology talk; I was neither the first nor the last, but I can say I worked it in before Sean did. See (.pdf):

    or (.ppt):

    It’s easy to deflect the Brooklyn question for a locally gravitationally bound system. But the subtler question is how a smooth cosmic expansion would affect a system bound purely by non-gravitational forces; this question is not typically addressed at the intro level, but I’ve given it a shot in my lectures.

  • gfl

    > It’s easy to deflect the Brooklyn question for a locally gravitationally bound system.

    Absolutely – seems to smack of there being one kind of gravity for the cosmos and another for “bound systems”. We had a punt of this as well in;

    Expanding Space: the Root of all Evil?
    Authors: Matthew J. Francis, Luke A. Barnes, J. Berian James, Geraint F. Lewis
    (Submitted on 3 Jul 2007)

    Abstract: While it remains the staple of virtually all cosmological teaching, the concept of expanding space in explaining the increasing separation of galaxies has recently come under fire as a dangerous idea whose application leads to the development of confusion and the establishment of misconceptions. In this paper, we develop a notion of expanding space that is completely valid as a framework for the description of the evolution of the universe and whose application allows an intuitive understanding of the influence of universal expansion. We also demonstrate how arguments against the concept in general have failed thus far, as they imbue expanding space with physical properties not consistent with the expectations of general relativity.

    Although I think Woody Allen is one of the un-funniest people on the planet.

  • Simon DeDeo

    While I believe that Brooklyn is not expanding, I occasionally invent for myself a thought experiment related to Brooklyn and have to waste an afternoon trying to puzzle my way back out again. There are subtle issues (as Paul notes!) hidden in these questions!

    When I first encountered the big bang (in a conceptual sense), for some reason I had a professor who would treat is-Brooklyn-expanding questions with great distain, and I think the occasional folly of my trying to invent increasingly tricky versions of the problem is a reaction to this.

    Actually, one thing I find becomes an issue is that I find integrals easier to understand than simple operations like division. Does anyone else have this problem? I think integrating a function is easier to imagine than dividing a function’s value at point x by its value at point y.

  • Pingback: Tuesday morning links! « Entertaining Research()

  • Belizean

    Note that everyone seems to be buying into some sort of Big Rip cosmology.


    I thought that the current best estimate for w (ratio of pressure to density), is something like -1.00 +/- 0.01.

    Is the Big Rip hysteria based on the possibility that w is -1.01?

  • Sean

    If we had constraints on w that were that good, nobody would be talking about building a satellite. Right now they are closer to 10% than 1%.

    I don’t think there is any hysteria, but the interest is based on the idea that it’s a plausible scenario that is consistent with the data.

  • Pingback: A quote from Annie Hall « Entertaining Research()

  • Joseph Smidt

    Speaking of expanding, anybody have any thoughts on this paper: ?

    It seems getting inflation from string theory might be more difficult then string thoeriists would like:

    “We analyze three explicit string models from the recent literature, each containing an infinite number of “vacuum” solutions. Our numerical investigation of some natural candidate inflatons, the so-called “moduli fields”, fails to find inflation…even having an infinite number of vacua does not guarantee having inflating ones. This may be an artifact of the simplicity of the models that we study. Instead, more complicated string theory models appear to be required, suggesting that explicitly identifying the inflating subset of the string landscape will be challenging.”

  • Jonathan Vos Post

    Brooklyn, where I spent ages 0.75 through 15.9, (specifically in Brooklyn Heights, around the corner from W. H. Auden, and in the building where Arthur Miller had lived, but which Marilyn Monroe preferred not to live, and downstairs from the penthouse where Andy Warhol filmed some of his first Ultraviolet catastrophes), was once the 5th largest city in the USA. It got merged in with New York City about the time that a tidal bulge became the Brooklyn Bridge feeding an accretion disk. This may fit SMOLUCHOWSKI EQUATIONS for coagulation, or may indicate Dark Matter at the cores of major metropolitan area, and Dark Energy driving populations to the suburbs and exurbs. Experts differ.

  • teadrinker

    Carl Sagan also came from Brooklyn, born there in 1934.

    Is there a connection, perhaps?


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Cosmic Variance

Random samplings from a universe of ideas.

About Sean Carroll

Sean Carroll is a Senior Research Associate in the Department of Physics at the California Institute of Technology. His research interests include theoretical aspects of cosmology, field theory, and gravitation. His most recent book is The Particle at the End of the Universe, about the Large Hadron Collider and the search for the Higgs boson. Here are some of his favorite blog posts, home page, and email: carroll [at] .


See More

Collapse bottom bar