HDTenEightyP/NetNews huggingface dataset:
From: dstamp@watserv1.waterloo.edu (Dave Stampe-Psy+Eng)
Newsgroups: sci.virtual-worlds
Subject: Re: TECH: Projecting LCD panels
Date: 23 Jul 92 04:11:23 GMT
Article-I.D.: watserv1.BrtqB1.D7E
Organization: University of Waterloo
Originator: hlab@milton.u.washington.edu



gt0418c@prism.gatech.edu (Shane Wm. McWhorter) writes:

>Am I wrong, or are the new RGB video projectors using LCDs? Those
>projectors are BRIGHT (and cheap). Are they are slide projectors with
>LCDs? They are very lightweight, so I doubt they are anything like the
>phosphor-based video projectors.
>
>For $5,000 or less each, seems they would make great additions to
>room-based VEs like CAVE... Throw in a few circular polarizers, and
>you wouldn't have to time multiplex. Double your resolution with 4 of
>them.

Alas, you can't really add polarizers to LCD panels: they already have
polarizers!  You'd have to add a diffuser or something to remove the
polarization, or lay one projector on its side (or rotate the panel
inside).  It would be VERY difficult to get the manufacturer to make
you a panel with flipped polarizers, and they're glued to the
(fragile) panel glass so you can't remove them and rotate them
yourself...


--------------------------------------------------------------------------
| My life is Hardware,                    |                              | 
| my destiny is Software,                 |         Dave Stampe          |
| my CPU is Wetware...                    |                              | 
| Anybody got a SDB I can borrow?         | dstamp@watserv1.uwaterloo.ca |
__________________________________________________________________________
From: bar-zeev@tortoise.cis.ohio-state.edu (avi bar-zeev)
Newsgroups: sci.virtual-worlds
Subject: Re: TECH: Text interfaces
Date: 24 Jul 92 16:07:39 GMT
Article-I.D.: cis.1992Jul24.160739.14623
Organization: The Ohio State University, Department of Computer and Information
Originator: hlab@milton.u.washington.edu


In article <1992Jul24.050746.16915@u.washington.edu> Jeremiah.Blatz@dartmouth.ed
u (Jeremiah Blatz) writes:
>
>As for controling VR through text, which I think was the original point
>of this thread, I think that is impossible, as much of the point of VR
>is displaying more information than can possibly be assimilated using
>other methods.
>
>jeremiah
>jerbl@dartmouth.edu

        Controlling VR through text is probably not the goal of anyone, but
text interfaces still have a role to play even if it may just be transitional.

        Although I understand your point, my philosophy differs in that I
strongly believe that we need to (ultimately) provide any sort of interface
people are most comfortable with.  Lets face it, no two people communicate
in exactly the same way.  Some are predominantly verbal/oral, some are
visual, and some can best express themselves and absorb certain kinds of
information literately.  My goal is not more bandwidth into our brains but
more resonance with the information.  I have to admit that text interfaces
are much more limited for me (and probably for you) but maybe not for someone
with extremely poor spatial relations.  

    That is not to say, a writer, for example, will not prefer
a predominantly oral mode or even that people may be equally
comfortable with all modes.  Choice is empowerment and that should
be, in my view, _one_ of the defining characteristics of VR.

Avi
Newsgroups: sci.virtual-worlds
From: BRAD SMITH <smithb@ALM.ADMIN.USFCA.EDU>
Subject: PHIL: Request for help/opinion in defining VR
Originator: hlab@milton.u.washington.edu
Organization: University of Washington
Date: Mon, 20 Jul 1992 10:57:18 GMT



It would seem that a flight simulator used to train and test pilots is
an example of virtual reality.  Agreed?  Now, at the other end of the
continuum, what about flight simulation on a PC?  Is it an example of
virtual reality?  Why?

Thank you for your help/opinion.

Brad Smith
smithb@alm.admin.usfca.edu
From: smithb@ALM.ADMIN.USFCA.EDU (BRAD SMITH)
Newsgroups: sci.virtual-worlds
Subject: ADMIN: Mail?
Date: 21 Jul 92 19:06:23 GMT
Organization: University of Washington
Originator: hlab@milton.u.washington.edu



Am I alone in not receiving any mail in the last 3 or 4 days?

-- Brad


[MODERATOR'S NOTE:  The mailer at milton, the University of Washington
host computer, could not handle the expanded mailing list for sci.
virtual-worlds.  If you would like to go on VIRTU-L, the mailing list
maintained at the U of Illinois, please send email to Professor Greg
Newby (gnewby@uxh.cso.uiuc.edu).  Please be patient, as Greg is on 
summer schedule.  And spread the note to the other mailing list folks,
who may not hear about this.

[If you're just worried about regular postings being delayed,
we got behind as I returned from Asia and Mark got ready to go off
to UNC. -- Bob Jacobson]
From: bar-zeev@tortoise.cis.ohio-state.edu (avi bar-zeev)
Subject: Re: BOOK: Consciousness Explained
Originator: hlab@milton.u.washington.edu
Organization: The Ohio State University, Department of Computer and Information 
Date: Mon, 27 Jul 1992 13:58:36 GMT


In article <1992Jul26.074851.9150@u.washington.edu>
plains!kmagel@uunet.UU.NET (ken magel) writes:

>In Daniel Dennett's book COnsciousness Explained, he claims that human beings
>will never be fooled by computers, no matter how powerful those computers
>eventually become.  This seems unrealistic?  Therefore, if we assume that
>eventually computers will be capable of providing virtual worlds which can 
>include interactions which fool the human beings interacting in the world, 
>what would be the ethics involved in such a situation?  Under what circum-
>stances should a virtual world be established which provides incorrect 
>experiences 
>to human beings who use it when those humans cannot determine that the
>experiences
>are incorrect?  Further, if the virtual world is sufficiently detailed, how 
>will humans be able to distinguish what they do in that world from what they 
>do in the "real"  world?  
>Will it matter that they cannot?

        This may be getting into religion (or at least metaphysics)
but how do we know that what we call the real (non-virtual) world is
not really virtual to someone else?  Our physical forms could be the
actors in this virtual universe while what we call the soul is the
user experiencing the system.  It's kind of funny that there is a
discussion on inhabiting objects in another thread since that could be
how we (the soul-part of us) inhabit the physical world.  All it
requires is "forgetting" an existence outside the virtual (or real)
one.

        The point of this is not to convince you of anything (I don't
necessarily believe it) but to point out that if we _could_ be living
in a virtual universe without knowing it, we have a real possibility
creating virtual universes ourselves in which user's forget (for a
time) they have another existence.  We seem to be very good at
redefining reality to fit what or where they believe they are.  I
coulkd give dozens of examples of cases where people convince
themselves that reality is what they think it is when that may not be
the case.

        The question of ethics, then, is important.  If we can define
a virtual hell and keep people there because they think they really
are in hell (and don't believe they can simply exit) then there's
obviously a problem.  On the other hand, being temporarily trapped in
a virtual world may be of great benefit to the learning process.  If
we are totally immersed, we won't have our real-life concerns tugging
at the back of our minds; we can totally concentrate on a problem.

Anyway, just rambling on...

Avi
From: thinman@netcom.com (Technically Sweet)
Newsgroups: sci.virtual-worlds
Subject: TECH: on real-time texture mapping
Date: 24 Jul 92 19:04:39 GMT
Article-I.D.: u.1992Jul26.074450.8737
Organization: International Foundation for Internal Freedom
Originator: hlab@milton.u.washington.edu


I stand corrected.  Mip-mapping operates by storing successively
larger square pixmaps which are manufactured from a given input pixmap.
To resample these maps to an arbitrary plane, you pick the appropriate
mipmap from the size of the target planar surface, calculate the
coordinates (called s and t) into the mipmap, and pull out the
required pixels.  The output will look nicer if pixels from
different mipmap levels are interpolated.  Here are references
for mipmaps and a competitive technique, summed-area tables.
(My informant prefers the latter, and mailed example source code
for doing the pixel lookups.  I'm checking with him on a source
code release.)

On mipmaps:

@INCOLLECTION {heckbert91,
        AUTHOR = "Heckbert, Paul S. and Moreton, Henry P.",
        TITLE = "Interpolation for Polygon Texture Mapping and Shading",
        BOOKTITLE = "State of the Art in Computer Graphics, Visualization and Mo
deling",
        PUBLISHER = "Springer Verlag",
        YEAR = 1991,
        EDITOR = "Rogers, David and Earnshaw, Rae"
}

@TECHREPORT{ tmpip,
        AUTHOR = "Heckbert, Paul S.",
        TITLE = "Texture Mapping Polygons in Perspective",
        INSTITUTION = "Computer Graphics Lab, New York Institute of Technology",
        YEAR = 1983,
        NUMBER = 13,
        MONTH = "April"
}


On summed-area tables:

@ARTICLE{summedtables,
        AUTHOR = "Crow, Franklin C.",
        TITLE = "Summed-Area Tables for Texture Mapping",
        JOURNAL = "Computer Graphics",
        YEAR = "1984",
        VOLUME = "Vol. 18",
        MONTH = "July"
}

-- 

Lance Norskog

Data is not information is not knowledge is not wisdom.
Newsgroups: sci.math
From: andyc@eliot.uucp (Andy Panda Collins)
Subject: Number Theory
Keywords: Number,Theory 
Organization: Systems Center, Inc., Reston, VA, USA
Distribution: na
Date: Thu, 23 Jul 1992 18:49:51 GMT


I don't know much about this news-group, but I thought
that I might post this list of number-theoretic numbers.

  Let N be an n-digit number which is separated into it's
  decimal digits, raise each digit to the nth power and sum
  them. Let N be a unique number if the sum is equal to N.

28116440335967  -->  The singular 14 digit number I've found!
--> Strangely there are no 12 or 13 digit numbers with
    this property. This is a certainty.
32164049650     -->  11 digit numbers are abundant.
40028394225
42678290603
49388550606
32164049651
94204591914
44708635679
82693916578
4679307774      -->  The rest of the list is verified,
912985153            but none of these are new.
472335975
534494836
146511208
24678050
24678051
88593477
1741725
4210818
9800817
9926315
548834
54748
92727
93084
1634
8208
9474
153
370
371
407

Strange things happen for alternate bases, but I haven't
compiled any lists. I would be interested.

Send any response to
  acollins@thor.tjhsst.edu, School address or
  uunet!eliot!andyc, Work address
From: ara@zurich.ai.mit.edu (Allan Adler)
Newsgroups: sci.math
Subject: function fields
Date: 21 Jul 92 05:59:32 GMT
Distribution: sci
Organization: M.I.T. Artificial Intelligence Lab.


I've wondered about this for some time and never found out one way or the
other...

Suppose that X and Y are compact complex manifolds. Is the function field of
X x Y equal to the quotient field of the tensor product of the function field
of X and the function field of Y ?

I know it is true for algebraic manifolds.

Allan Adler
ara@altdorf.ai.mit.edu
From: dlm@sjfc.UUCP (Don Muench)
Newsgroups: sci.math
Subject: Western NY vs "upstate" (was Re: American mathematical hegemony)
Summary: From Rochester, NY, let's go onto something else
Date: 26 Jul 92 04:53:36 GMT
Organization: St. John Fisher College, Rochester, NY

In article <1106@kepler1.rentec.com>, andrew@rentec.com (Andrew Mullhaupt) writes:
> 
> - This doesn't sound right - I though he claims to live in Rochester, not
> Buffalo. I also suspect him of not being autocthonous. People from both
> Rochester and Buffalo know they live in _Western_ New York, not _upstate_.
> 
> I suspect that the guy is originally from downstate - NYC or Long Island and
> that this means the wings may not be hot enough...
> 
> Later,
> Andrew 'Born in Buffalo' Mullhaupt


No, Andrew...I am from Rochester.  Yes, I am aware we prefer "Western NY"
to "Upstate", but the "upstate" description means different things to
an upstater and to a downstater.  The "downstater" (a person fromthose regions
near NY City) call anything else "upstate".  If you're from northern NY State,
you would almost invariably say you are from "the north country".  And that
wonderful accent that we have from Syracuse westward to Buffalo sets us
apart from most of the rest of the state.  I will be pleased to treat my
British hosts to this unique accent.  At the same time I will enjoy theirs
and marvel at the rich diversity.

Chicken wings are the greatest culinary treat when the sauce is "nuclear"
and the flames blast forth from the nose and mouth.

Well, i think we've talked this thread to death, especially since it no
longer deals with "math hegemony".

Yours,
Don 'Born in Rochester' Muench  (Go Bills!)
Newsgroups: sci.math
From: bula@snoopy (W. Bula)
Subject: Olympic question
Summary: What is 1st homotopy group of R^3\setminus Olympic Rings?
Keywords: homotopy, olimpic
Organization: University of Saskatchewan, Saskatoon, Canada
Date: Thu, 30 Jul 1992 23:51:17 GMT

Hi!

I wonder if this question comes up every four years, but anyway...
Has anyone on the net ever considered topology of the complement of
olympic rings in the 3D space? It would be nice to see e.g. the first
homotopy group of this space.

Regards,



-- 
# Witold D. Bula         # bula@snoopy.USask.Ca #  You may send me a letter  #
# Dept. of Math.         #  (306) 966-6110      #    BUT if you want me to   # 
# Univ. of Saskatchewan  #                      #  answer, sent it by e-mail #
# Saskatoon, SK, S7N 0W0 # DISCLAIMER: (usual)  #                      W.B.  #
From: edgar@function.mps.ohio-state.edu (Gerald Edgar)
Newsgroups: sci.math
Subject: Re: Gordon & Breach suit against AMS
Date: 24 Jul 1992 14:23:01 -0400
Organization: The Ohio State University, Dept. of Math.
NNTP-Posting-Host: function.mps.ohio-state.edu

In article <BrwLMJ.E1K@watserv1.waterloo.edu> shallit@graceland.waterloo.edu (Jeffrey Shallit) writes:
>I've heard several times from different sources that after the AMS
>published a list of journals and how much they cost, they were sued
>by a publisher who tried to prevent release of this information.
>Perhaps the publisher was Gordon & Breach.  
>
>Can anyone verify this?  In particular, I would like to have a 
>pointer to a newspaper or journal article that discusses the
>suit.

The AMS published comparitive cost figures for research journals in
1984, 1986, 1988, and 1989.  Gordon & Breach objected to the figures.

G&B explain their side in an ad in the Notices of the AMS, January, 1990,
pages 92--93.

AMS explain their side in an editorial in the same issue, pages 2 and 18.

An article on this is in the Notices in 1990 (vol. 37 no. 6) page 681.
It contains other references, as well.  According to it, Gordon & Breach
filed suit in Germany (based on their law prohibiting comparative advertising)
against the American Mathematical Society.  G & B had previously filed a
similar suit against the American Physical Society and the
American Institute of Physics.


-- 
  Gerald A. Edgar                Internet:  edgar@mps.ohio-state.edu
  Department of Mathematics      Bitnet:    EDGAR@OHSTPY
  The Ohio State University      telephone: 614-292-0395 (Office)
  Columbus, OH 43210             -292-4975 (Math. Dept.) -292-1479 (Dept. Fax)
From: rose@fsu1.cc.fsu.edu (Kermit Rose)
Newsgroups: sci.math
Subject: Re: ? Quick algorithm for random covering sets ?
Date: 23 Jul 92 05:13:39 GMT
Reply-To: rose@fsu1.cc.fsu.edu
Organization: Florida State University
News-Software: VAX/VMS VNEWS 1.3-4

In article <SQUASH.92Jul17215435@bourbaki.msri.org>, squash@bourbaki.msri.org (Jonathan King) writes...
>Do any of you have a suggestion for a "fast" algorithm which:
>   Given positive integers D > K > 2, the algorithm hands me K "random"
>non-empty subsets of {1,...,D} whose union is all of {1,...,D} and with no
>element common to all K sets.
> 
>"Fast" doesn't have a technical definition here, -the algorithm needs to go
>inside a deeply nested loop.  "Random" isn't precise either but at least the
>probability that element d is in set S_k should be close to independent of d.
> 
>I'm looking for a easily-programmable, practical algorithm, even if it has
>theoretical shortcomings.        -Jonathan,  squash@math.ufl.edu

There should be real numbers b_1,b_2,...b_K with the property that
the sequences 
{[b_1],[2 b_1],[3 b_1],....}
{[b_2],[2 b_2],[3 b_2],...}
..    
{[b_K],[2 b_K],[3 b_K],...}  have pairwise null intersection.
   [x] means largest integer less than or equal to x.

I do not remember how to find these numbers.  The value of D is not 
relevant since the b's are the same for all D. 

rose@fsu1.cc.fsu.edu          To be sure I see your response, use e-mail.
-----------------------------------------------------------------------
Be of good cheer, for it is much more fun than being depressed.
From: mapsj@gdr.bath.ac.uk (Simon Juden)
Newsgroups: sci.math
Subject: Re: An interesting limit problem.
Date: 28 Jul 92 19:10:37 GMT
Organization: School of Mathematics, University of Bath, UK

>mattm@lure.latrobe.edu.au writes:

[stuff deleted]

>Will someone please back me up, and say that no one learning
>Calculus should ever be allowed anywhere _NEAR_ Mathematica?
>(When I say 'learning Calculus' I mean the first two or three
>semesters)

I could hardly agree more. Mathematica should be viewed as a fancy calculator
(which, essentially, is what it is). Very good and very useful, BUT undergrads
HAVE to learn basic concepts and manipulative skills before they're let near
it. Otherwise they will never become mathematicians, but rather computer
operators. Also they'll never FULLY understand subtle concepts or follow harder
arguments used in difficult proofs if they haven't had to do things with their
bare hands first. Like any good similar system Mathematica can be very helpful
to the professional mathematician. But I believe such gadgets can also do
irreparable harm unless used appropriately. I also believe children should not
be given calculators until they can do sums without them. But doubtless these
views will get me flamed...

Simon
From: br310026@bronze.ucs.indiana.edu (william p. ziemer)
Newsgroups: sci.math
Subject: Re: Complex Analysis
Keywords: i,e,pi
Date: 24 Jul 92 13:54:54 GMT
Distribution: na
Organization: Indiana University

In article <1992Jul23.195728.6153@eliot.uucp> andyc@eliot.uucp (Andy Panda Collins) writes:
>
>I've got some questions about complex analysis and I don't have access to a good book store that carries heavy-duty math texts. Can someone suggest some good texts? I have some basic knowledge of the subject, but would like some information on how to analyze complex functions of complex variables. Thanks a bunch. e^(i*_pi_)=(-1)!

One of the standard textbooks on complex analysis is 
John Conway's book, which appeared as Vol 14 of Springers series in
Graduate Texts in Mathematics. In the same series you can find the
book of Reinhold Remmert, which is more has more connections to 
abstract algebra than Conway's book. However, Remmerts book was 
originally planned as a two volume book - the second volume never
appeared, however. This book is also available in the Graduate Texts
in Mathematics series from Springer. Since it is also part of the 
Readings in Mathematics series, it also provides some historical 
background. 

- Jurgen Singer 
(this was posted from a guest account, please send any replies to
mece1uu@jetson.uh.edu)
Newsgroups: sci.math
From: jnjohann@immd4.informatik.uni-erlangen.de (Jan Johannsen)
Subject: Re: You know, the integers (was: Re: Stupid question about FLT)
Organization: CSD., University of Erlangen
Date: Tue, 21 Jul 1992 14:49:05 GMT



tycchow@riesz.mit.edu (Timothy Y. Chow) writes:

>In article <1992Jul20.173716.6310@galois.mit.edu> I wrote:
>>In article <22326.Jul2014.40.3392@virtualnews.nyu.edu> brnstnd@nyu.edu (Dan Bernstein) writes:
>>>The answer is, to define a mathematical entity once and for all takes
>>>nothing beyond a fixed set of axioms and (syntactic) rules for deriving
>>>truths from those axioms. The trick is to find *interesting* entities.
>>
>>But this is precisely the point!  Consider the "REAL" integers:  every
>>set of axioms and syntactic rules that the "REAL" integers satisfies
>>also admits nonstandard models.  How then do you propose to "define" the
>>REAL integers with a fixed set of axioms and syntactic rules?
>>
>>Perhaps you might try to use the fact that in ZFC one can formulate a
>>proof that any two Peano structures are isomorphic.  In that case,
>>consider nonstandard models of ZFC...

>Reading over this I thought it somewhat cryptic, so here's an expansion.

>I take "fixed set of axioms and syntactic rules" to mean a first-order
>axiomatization.  Now it is well-known that there are models that are
>elementarily equivalent (i.e., the same first-order sentences are true)
>to the "real integers" but which are not isomorphic to the real integers.
>So my challenge was to ask for a "definition" of the real integers of the
>kind Dan Bernstein wants.

Following this thread I always wondered why noone ever mentioned the following
possible answer:

Take the axioms for the upper half of a discretely ordered ring (about 15 axioms)
and add the (infinite) \omega-rule of induction:

  A(0)   A(s0)  A(ss0)  A(sss0) ....
--------------------------------------
             \forall x A(x)

Then every true (first order) sentence about the integers is provable 
with this machinery, and vice versa.
Thus we have characterized the integers up to elementary equivalence.

And if anyone out there complains about the non-constructiveness of this
approach, remember the theorem (I forgot the reference) that _recursive_
proofs in this system suffice to do the same thing.

[Stuff deleted]
>-- 
>Tim Chow     tycchow@math.mit.edu

J. Johannsen     jnjohann@immd1.uni-erlangen.de