From boud w astro.uni.torun.pl  Thu Mar 13 13:48:30 2003
From: boud w astro.uni.torun.pl (Boud Roukema)
Date: Thu, 13 Mar 2003 13:48:30 +0100 (MET)
Subject: astro-ph/0302496 - T^1 model in WMAP data? - compare astro-ph/0007140
Message-ID: <Pine.SOL.4.44.0303131347050.16287-100000@hevelius.astro.uni.torun.pl>


 


From boud w astro.uni.torun.pl  Wed Mar 19 20:05:07 2003
From: boud w astro.uni.torun.pl (boud)
Date: Wed, 19 Mar 2003 20:05:07 +0100 (MET)
Subject: topology - WMAP - urgent
Message-ID: <Pine.SOL.4.44.0303191956460.570-100000@hevelius.astro.uni.torun.pl>

Witam,
   Micha³, Bartek, anyone else interested.

Now that there's some big time media coverage, anyone interested
in working together on this? IMHO it's urgent to do the analysis
ourselves.

I haven't fully understand Marek's comments, but I think he's just
playing safe ;) - no harm there.

Anyone who sees signs that our North/South American and or European
colleagues have done something concrete on this, please say and point
to the URL!


Boud

amr wrote:
> Artyku³ o odkryciu ("odkryciu" ?) Tegmarka:
> http://www.gazeta.pl/nauka/1,34148,1376101.html

> Krytyka Marka Demiañskiego:
> http://www1.gazeta.pl/nauka/1,34148,1376526.html



---------- Forwarded message ----------
> Date: Wed, 19 Mar 2003 12:57:53 +0100 (MET)
> From: Programme National de Cosmologie <pnc at iap.fr>
> To: diffusion PNC <pnc at iap.fr>
> Subject: divers ...

---------------------------------------------------------------------------
    PNC PNC PNC           http://www.iap.fr/pnc/         PNC PNC PNC PNC
---------------------------------------------------------------------------

 4. Extraits d'un article du New-York Times du 11 mars 2003
    "Universe as Doughnut: New Data, New Debate"

    The New York Times
    March 11, 2003
    Universe as Doughnut: New Data, New Debate
    By DENNIS OVERBYE

    Long ago in the dawn of the computer age, college students often
    whiled away the nights playing a computer game called Spacewar. It
    consisted of two rocket ships attempting to blast each other out
    of the sky with torpedoes while trying to avoid falling into a
    star at the center of the screen.

    Although cartoonish in appearance, the game was amazingly faithful
    to the laws of physics, complete with a gravitational field that
    affected both the torpedoes and the rockets. Only one feature
    seemed outlandish: a ship that drifted off the edge of the screen
    would reappear on the opposite side.

    Real space couldn't work that way.

    Or could it?

    Imagine that the Spacewar screen is wrapped around to form a
    cylinder or a section of a doughnut so that the two edges meet.

    That is the picture of space, some cosmologists say, that has been
    suggested by a new detailed map of the early universe. Their
    analysis of this map has now provided a series of hints  though
    only hints  that the universe may have a more complicated shape
    than astronomers presumed.

      ...

    This mirror game is not limited to cubes and doughnuts. Over the
    years mathematicians, particularly Dr. William Paul Thurston, now
    at the University of California at Davis, and Dr. Jeffrey Weeks,
    an independent mathematician, have speculated about universes
    composed of various polyhedrons glued together in various ways.

    In 1996 the French astronomer Dr. Jean-Pierre Luminet of the Paris
    Observatory and his colleagues Dr. Roland Lehoucq and Dr. Marc
    Lachieze-Rey, both of the Center for Astrophysical Studies in
    Saclay, France, developed a method called "cosmic
    crystallography," using galaxy statistics to detect and diagnose
    the repeating periodic patterns that would be created in the sky
    by light going around and around in differently shaped universe.


    Finite or Infinite?
    Problems Are Posed
    For Favored Theory

        ...




 


From boud w astro.uni.torun.pl  Mon Mar 31 19:34:10 2003
From: boud w astro.uni.torun.pl (boud)
Date: Mon, 31 Mar 2003 19:34:10 +0200 (CEST)
Subject: "projective sphere" (fwd)
Message-ID: <Pine.LNX.4.21.0303311931040.30259-100000@semuramat.camk.edu.pl>

hi, 
  i received this from a friend.

The projective sphere is the 2-sphere S^2 where each point is
identified with its opposite point. So the fundamental polygon 
is a hemisphere.  Geodesics only intersect once in the projective
sphere.

> Hi Boud, 
> what an irony, but I am looking for your help with Polish !!!
> Could you or your collaborators on topology in Torun 
> enlighten me with Polish term for "projective sphere" ?
> Thanks in advance,

Can anyone help?

boud