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␈↓ ↓H␈↓α␈↓ αkINTERSTELLAR TRAVEL WITH 20TH CENTURY TECHNOLOGY

␈↓ ↓H␈↓␈↓ α_There␈α
are␈α
about␈α
a␈αhundred␈α
billion␈α
stars␈α
in␈αour␈α
galaxy␈α
(about␈α
25␈αstars␈α
for␈α
each␈α
person␈αon
␈↓ ↓H␈↓the␈αearth␈αtoday)␈αand␈αit␈αwould␈αbe␈αwonderful␈αif␈αwe␈αcould␈αtravel␈αto␈αthem␈αin␈αa␈αfew␈αmonths␈αor␈αyears.
␈↓ ↓H␈↓Unfortunately,␈α⊂the␈α⊂galaxy␈α⊂is␈α⊂a␈α⊂100,000␈α⊂light␈α⊃years␈α⊂across␈α⊂(30,000␈α⊂light␈α⊂years␈α⊂from␈α⊂here␈α⊃to␈α⊂the
␈↓ ↓H␈↓galactic␈α
core),␈α
and␈α
our␈α
present␈α
science␈α
tells␈α
us␈αthat␈α
we␈α
can't␈α
travel␈α
faster␈α
than␈α
the␈α
speed␈α
of␈αlight.
␈↓ ↓H␈↓Present␈α∀science␈α∀may␈α∀be␈α∃wrong␈α∀about␈α∀this,␈α∀but␈α∀the␈α∃theory␈α∀of␈α∀relativity␈α∀has␈α∃survived␈α∀more
␈↓ ↓H␈↓experimental tests than almost any other part of physics.

␈↓ ↓H␈↓␈↓ α_For␈αonce,␈αlet's␈αbe␈αconservative␈αand␈αask␈αwhat␈αinterstellar␈αtravel␈αis␈αsurely␈αpossible␈αrather␈αthan
␈↓ ↓H␈↓what␈αwe␈αmight␈αdo␈αif␈αNature␈αis␈αmore␈αco-operative␈αthan␈αwe␈αcan␈αbe␈αsure␈αof.␈α We␈αshall␈αassume␈αonly
␈↓ ↓H␈↓present␈α
science␈α
and␈α
not␈α
much␈α
beyond␈αpresent␈α
technology.␈α
 We␈α
will␈α
have␈α
to␈αaccept␈α
multi-generation
␈↓ ↓H␈↓journeys, consider how they can be done, and why people might want to.

␈↓ ↓H␈↓␈↓ α_One␈α
rocket␈α
that␈αwill␈α
surely␈α
work␈αuses␈α
a␈α
nuclear␈αreactor␈α
to␈α
generate␈αelectricity␈α
and␈α
uses␈αthe
␈↓ ↓H␈↓electricity␈α∞to␈α∞propel␈α
charged␈α∞particles␈α∞out␈α∞the␈α
back␈α∞-␈α∞the␈α
reaction␈α∞propelling␈α∞the␈α∞rocket␈α
forward.
␈↓ ↓H␈↓The␈αreactors␈αnow␈αused␈αin␈αnuclear␈αsubmarines␈αwould␈αeven␈αwork;␈αthey␈αproduce␈αthe␈αmost␈αpower␈αfor
␈↓ ↓H␈↓a␈αgiven␈αmass␈αof␈αreactor␈αof␈αany␈αexisting␈αreactor,␈αbut␈αa␈αnew␈αdesign␈αcould␈αdo␈αmuch␈αbetter.␈α Rockets
␈↓ ↓H␈↓that␈αexpel␈αcharged␈αparticles␈αhave␈αbeen␈αbuilt,␈αone␈αis␈αbeing␈αtested␈αnow␈αin␈αorbit,␈αand␈αNASA's␈αhopes
␈↓ ↓H␈↓for a 1986 ␈↓↓rendez-vous␈↓ with Halley's comet were based on an electric rocket (solar powered).

␈↓ ↓H␈↓␈↓ α_Optimizing␈α
a␈α
rocket␈αsystem␈α
that␈α
generates␈α
power␈αand␈α
uses␈α
that␈αpower␈α
to␈α
expel␈α
a␈α"working
␈↓ ↓H␈↓fluid"␈αis␈αmore␈αcomplicated␈αthan␈αoptimizing␈αa␈αchemical␈αrocket.␈α In␈αa␈αchemical␈αrocket,␈αthe␈α␈↓↓figure␈αof
␈↓ ↓H␈↓↓merit␈↓␈α
(the␈αnumber␈α
that␈α
tells␈αhow␈α
good␈α
the␈αsystem␈α
is)␈αis␈α
the␈α
velocity␈αof␈α
the␈α
exhaust␈α-␈α
the␈αhigher␈α
the
␈↓ ↓H␈↓better.␈α∞ The␈α∞figure␈α
of␈α∞merit␈α∞of␈α
a␈α∞power␈α∞limited␈α
rocket␈α∞is␈α∞the␈α
power␈α∞per␈α∞unit␈α
mass␈α∞of␈α∞the␈α
rocket
␈↓ ↓H␈↓system␈α∪minus␈α∪fuel␈α∀and␈α∪working␈α∪fluid,␈α∀and␈α∪the␈α∪exhaust␈α∪velocity␈α∀can␈α∪be␈α∪chosen␈α∀to␈α∪optimize
␈↓ ↓H␈↓performance.␈α The␈αlimitation␈αon␈αpower␈αwill␈αbe␈α
dominated␈αby␈αthe␈αneed␈αto␈αdissipate␈αwaste␈α
heat␈αby
␈↓ ↓H␈↓radiation,␈α⊂because␈α⊂dissipating␈α⊂a␈α⊃lot␈α⊂of␈α⊂heat␈α⊂requires␈α⊃either␈α⊂a␈α⊂high␈α⊂temperature␈α⊃which␈α⊂reduces
␈↓ ↓H␈↓efficiency␈αor␈αa␈αbig␈αradiator␈αwhich␈αweighs␈αa␈αlot␈αand␈αhas␈αto␈αbe␈αaccelerated␈αalong␈αwith␈αthe␈αpayload.
␈↓ ↓H␈↓Too␈α
high␈α
an␈α
exhaust␈α
velocity␈αproduces␈α
a␈α
low␈α
thrust␈α
for␈α
a␈αgiven␈α
power␈α
and␈α
this␈α
makes␈αthe␈α
journey
␈↓ ↓H␈↓take long.  Too low an exhaust velocity requires an excessive mass of working fluid.

␈↓ ↓H␈↓␈↓ α_Between␈α∂the␈α⊂extremes␈α∂there␈α∂is␈α⊂an␈α∂optimum␈α∂exhaust␈α⊂velocity␈α∂for␈α∂a␈α⊂given␈α∂journey,␈α⊂and␈α∂it
␈↓ ↓H␈↓turns␈α⊃out␈α∩that␈α⊃this␈α⊃velocity␈α∩should␈α⊃vary␈α⊃during␈α∩the␈α⊃journey.␈α⊃ Consider␈α∩a␈α⊃journey␈α∩through␈α⊃a
␈↓ ↓H␈↓distance␈α∞␈↓↓s␈↓,␈α∞starting␈α∞from␈α∞zero␈α∞velocity␈α∞and␈α
ending␈α∞at␈α∞zero␈α∞velocity.␈α∞ Assume␈α∞that␈α∞the␈α
propulsion
␈↓ ↓H␈↓system␈α∞has␈α
a␈α∞␈↓↓specific␈α∞power␈α
p␈↓,␈α∞i.e.␈α∞␈↓↓p␈↓␈α
is␈α∞the␈α
the␈α∞power␈α∞output␈α
of␈α∞the␈α∞system␈α
divided␈α∞by␈α∞its␈α
mass.
␈↓ ↓H␈↓Finally,␈αlet␈αthe␈αmass␈αratio␈αbe␈α␈↓↓k␈↓,␈αi.e.␈α␈↓↓k␈↓␈αkilograms␈αstart␈αthe␈αjourney␈αfor␈αevery␈αkilogram␈α
that␈αarrives.
␈↓ ↓H␈↓The time ␈↓↓T␈↓ of the journey is then given by the formula

␈↓ ↓H␈↓1)␈↓ α8{   ␈↓↓T = 1.8s␈↓∧2/3␈↓↓p␈↓∧-1/3␈↓↓(log k)␈↓∧-1/3␈↓.

␈↓ ↓H␈↓␈↓ α_We␈α
will␈αspare␈α
the␈αreader␈α
the␈α
derivation␈αof␈α
the␈αformula␈α
using␈αcalculus␈α
of␈α
variations.␈α (The
␈↓ ↓H␈↓part␈α∩involving␈α∩␈↓↓s␈↓␈α∩and␈α∩␈↓↓p␈↓␈α∩can␈α∩be␈α∩derived␈α∩by␈α∩an␈α∩easy␈α∩method␈α∩that␈α∩physicists␈α∩call␈α∩dimensional
␈↓ ↓H␈↓analysis).␈α∞  However,␈α∞the␈α∂formula␈α∞has␈α∞consequence␈α∞that␈α∂should␈α∞interest␈α∞even␈α∂the␈α∞mathematically
␈↓ ↓H␈↓handicapped reader.

␈↓ ↓H␈↓␈↓ α_First␈αconsider␈αthe␈α␈↓↓s␈↓∧2/3␈↓␈α part.␈α The␈αtime␈αrequired␈αfor␈αthe␈αjourney␈αis␈αless␈αthan␈αproportional␈αto
␈↓ ↓H␈↓the␈αtime.␈α A␈αsimple␈αexplanation␈α
is␈αthat␈αon␈αa␈αlonger␈αjourney␈α
we␈αcan␈αuse␈αour␈αpower␈α
source␈αlonger,
␈↓ ↓H␈↓␈↓ εH␈↓ 91


␈↓ ↓H␈↓and␈α∞therefore␈α
can␈α∞use␈α
a␈α∞higher␈α∞average␈α
exhaust␈α∞velocity␈α
and␈α∞achieve␈α
a␈α∞higher␈α∞average␈α
velocity
␈↓ ↓H␈↓during␈α∂the␈α∞journey.␈α∂ Its␈α∞consequence␈α∂is␈α∞that␈α∂reaching␈α∞stars␈α∂80␈α∞light␈α∂years␈α∞away␈α∂takes␈α∂only␈α∞four
␈↓ ↓H␈↓times␈αas␈αlong␈αas␈αreaching␈αstars␈α10␈αlight␈αyears␈αaway␈α-␈αnot␈αeight␈αtimes␈αas␈αlong.␈α Since␈αwe␈αcan␈αexpect
␈↓ ↓H␈↓512␈α⊃times␈α⊃as␈α⊂many␈α⊃stars␈α⊃in␈α⊃that␈α⊂zone,␈α⊃it␈α⊃means␈α⊂that␈α⊃if␈α⊃any␈α⊃stars␈α⊂are␈α⊃visitable,␈α⊃many␈α⊃will␈α⊂be
␈↓ ↓H␈↓visitable.

␈↓ ↓H␈↓␈↓ α_The␈α␈↓↓p␈↓∧-1/3␈↓␈αterm␈αis␈αalso␈αinteresting.␈α It␈α
means␈αthat␈αthe␈αrocket␈αsystem␈αmust␈αbe␈αimproved␈α
by␈αa
␈↓ ↓H␈↓factor␈αof␈αa␈α1000␈αin␈αorder␈αto␈αreduce␈αthe␈αtravel␈αtimes␈αby␈αa␈αfactor␈αof␈α10.␈α Conversely,␈αyou␈αdon't␈αlose
␈↓ ↓H␈↓much␈α
by␈αa␈α
bulkier␈α
system␈αwith␈α
a␈α
low␈αspecific␈α
power.␈α Perhaps␈α
it␈α
also␈αmeans␈α
that␈α
very␈αadvanced
␈↓ ↓H␈↓civilizations␈αwill␈αonly␈α
be␈αable␈αto␈αtravel␈α
a␈αlittle␈αfarther␈αthan␈α
backward␈αcivilizations.␈α The␈α␈↓↓(log␈α
k)␈↓∧-1/3␈↓
␈↓ ↓H␈↓term tells us that starting with a very large mass doesn't help a lot either.

␈↓ ↓H␈↓␈↓ α_Table␈α∞1␈α∞gives␈α∞some␈α
travel␈α∞times␈α∞for␈α∞different␈α
assumptions␈α∞about␈α∞the␈α∞distance,␈α∞the␈α
specific
␈↓ ↓H␈↓power, and the mass-ratio.

␈↓ ↓H␈↓table 1

␈↓ ↓H␈↓␈↓ α_I␈αdon't␈αclaim␈α
this␈αis␈αthe␈α
only␈αpossible␈αmethod␈α
of␈αinterstellar␈αtravel␈α
or␈αeven␈αthe␈α
best,␈α␈↓αbut␈αit␈α
is
␈↓ ↓H␈↓αone␈αwe␈αcan␈αbe␈αsure␈αwill␈αwork␈↓.␈α Therefore,␈αour␈αspeculations␈αabout␈αthe␈αoccupation␈αof␈αthe␈αuniverse
␈↓ ↓H␈↓by␈α⊂humans␈α⊂or␈α⊃other␈α⊂intelligences␈α⊂should␈α⊃be␈α⊂based␈α⊂on␈α⊃having␈α⊂at␈α⊂least␈α⊃this␈α⊂good␈α⊂a␈α⊃method␈α⊂of
␈↓ ↓H␈↓interstellar␈α∩travel.␈α∩ The␈α∩scientists␈α∩interested␈α∩in␈α∩interstellar␈α∩communication␈α∩like␈α∩to␈α∩assume␈α⊃that
␈↓ ↓H␈↓interstellar travel is impossible.

␈↓ ↓H␈↓␈↓ α_Suppose␈α∪that␈α∪this␈α∀is␈α∪the␈α∪best␈α∀we␈α∪can␈α∪do␈α∪technologically.␈α∀ When␈α∪can␈α∪we␈α∀expect␈α∪what
␈↓ ↓H␈↓interstellar travel?

␈↓ ↓H␈↓α␈↓ β#SCENARIOS FOR LAUNCHING INTERSTELLAR TRAVEL

␈↓ ↓H␈↓␈↓ α_There are several cases.

␈↓ ↓H␈↓␈↓ α_1.␈α∀Suppose␈α∃that␈α∀humanity␈α∃remains␈α∀relatively␈α∃peaceful,␈α∀solves␈α∃its␈α∀energy␈α∃and␈α∀resource
␈↓ ↓H␈↓problems␈α∀well␈α∀enough␈α∪so␈α∀that␈α∀life␈α∪is␈α∀no␈α∀worse␈α∪than␈α∀today,␈α∀and␈α∪retains␈α∀its␈α∀enthusiasm␈α∪for
␈↓ ↓H␈↓technology.␈α∞ Suppose␈α∞also␈α
that␈α∞during␈α∞the␈α
next␈α∞thousand␈α∞years␈α
we␈α∞do␈α∞not␈α
become␈α∞aware␈α∞of␈α
any
␈↓ ↓H␈↓other␈α
intelligence␈α∞in␈α
the␈α
universe.␈α∞ In␈α
that␈α
case␈α∞we␈α
can␈α
predict␈α∞the␈α
time␈α
of␈α∞arrival␈α
at␈α∞the␈α
nearer
␈↓ ↓H␈↓stars␈α⊂more␈α⊂accurately␈α⊂than␈α⊂we␈α⊂can␈α⊂predict␈α⊂the␈α⊂time␈α⊂of␈α⊂departure.␈α⊂ Almost␈α⊂certainly␈α∂interstellar
␈↓ ↓H␈↓expeditions will arrive at the nearer stars before the year 3000 and most likely before 2500.

␈↓ ↓H␈↓␈↓ α_Clearly␈α∞it␈α∂is␈α∞pointless␈α∞to␈α∂start␈α∞a␈α∞thousand␈α∂year␈α∞expedition␈α∞at␈α∂a␈α∞time␈α∞when␈α∂waiting␈α∞twenty
␈↓ ↓H␈↓years␈α∩to␈α∩start␈α∪will␈α∩reduce␈α∩the␈α∩journey␈α∪to␈α∩900␈α∩years.␈α∩ If␈α∪technology␈α∩based␈α∩on␈α∪present␈α∩science
␈↓ ↓H␈↓improves␈α∞at␈α∞its␈α∂present␈α∞rate,␈α∞this␈α∂will␈α∞be␈α∞true␈α∞for␈α∂one␈α∞or␈α∞two␈α∂hundred␈α∞years,␈α∞e.g.␈α∂an␈α∞expedition
␈↓ ↓H␈↓starting in the year 2100 will arrive before an expedition starting in the year 2000.

␈↓ ↓H␈↓␈↓ α_Most␈α∞likely,␈α∞before␈α∞the␈α∞first␈α∞expedition,␈α∞much␈α
more␈α∞will␈α∞be␈α∞known␈α∞about␈α∞the␈α∞prospects␈α
of
␈↓ ↓H␈↓planets␈αand␈αasteroids␈αaround␈α
the␈αpotential␈αtargets.␈α Large␈α
space-based␈αtelescopes␈αcan␈αanswer␈α
many
␈↓ ↓H␈↓of␈α∂these␈α∞questions␈α∂and␈α∂are␈α∞much␈α∂cheaper␈α∂than␈α∞even␈α∂unmanned␈α∂probes.␈α∞ A␈α∂fly-by␈α∂mission␈α∞that
␈↓ ↓H␈↓accelerates␈αall␈α
the␈αway␈αtakes␈α
half␈αthe␈α
time␈αof␈αa␈α
mission␈αthat␈α
must␈αstop,␈αbut␈α
it␈αmust␈αcollect␈α
whatever
␈↓ ↓H␈↓information it will radio back in a short time while travelling at high velocity.
␈↓ ↓H␈↓␈↓ εH␈↓ 92


␈↓ ↓H␈↓␈↓ α_2.␈α⊃There␈α⊃is␈α⊃a␈α⊃danger␈α⊃that␈α⊃the␈α⊃anti-technology␈α⊃intellectual␈α⊃disease␈α⊃will␈α⊃prevail␈α⊃and␈α⊃that
␈↓ ↓H␈↓humanity␈α∞will␈α
lose␈α∞its␈α∞enthusiasm␈α
for␈α∞science␈α
and␈α∞technology,␈α∞abandon␈α
space␈α∞travel␈α∞and␈α
nuclear
␈↓ ↓H␈↓energy,␈αand␈αenter␈αa␈αnew␈αdark␈αages␈αin␈αwhich␈αthe␈αnecessary␈αscience␈αwill␈αbe␈αforbidden.␈α Fortunately,
␈↓ ↓H␈↓this␈α∩can't␈α∩happen␈α∪if␈α∩even␈α∩one␈α∩country␈α∪holds␈α∩out,␈α∩and␈α∩the␈α∪others␈α∩won't␈α∩or␈α∩can't␈α∪conquer␈α∩it.
␈↓ ↓H␈↓Moreover,␈α∞if␈α∞anti-technology␈α∞doesn't␈α∞conquer␈α∂the␈α∞U.S.␈α∞ in␈α∞the␈α∞next␈α∂50␈α∞years,␈α∞it␈α∞will␈α∞be␈α∂too␈α∞late,
␈↓ ↓H␈↓because␈αby␈αthen␈αthere␈αwill␈αcolonies␈αin␈αinterplanetary␈αspace␈αwhose␈αinhabitants␈αwill␈αbe␈αself-selected
␈↓ ↓H␈↓for␈α≠liking␈α~technology␈α≠and␈α~adventurousness.␈α≠ Such␈α~colonists␈α≠will␈α~be␈α≠tempted␈α≠to␈α~declare
␈↓ ↓H␈↓independence anyway and will be able to launch an interstellar expedition if they have to escape.

␈↓ ↓H␈↓␈↓ α_3.␈α
In␈α∞fact,␈α
if␈α∞interstellar␈α
travel␈α
continues␈α∞to␈α
require␈α∞multi-generation␈α
expeditions,␈α∞escape␈α
is
␈↓ ↓H␈↓one␈αof␈αthe␈αmore␈αprobable␈αmotivations␈αfor␈αthem.␈α One␈αpossibility␈αis␈αthat␈αa␈αcolony␈αin␈αinterplanetary
␈↓ ↓H␈↓space␈αalready␈αruns␈αafoul␈αof␈αa␈αwould-be␈αinterplanetary␈αgovernment␈αor␈αgovernments.␈α Perhaps␈αthey
␈↓ ↓H␈↓keep␈α∪slaves,␈α∪perhaps␈α∪they␈α∩practice␈α∪free␈α∪enterprise,␈α∪perhaps␈α∩they␈α∪won't␈α∪acknowledge␈α∪the␈α∩true
␈↓ ↓H␈↓religion,␈α∪perhaps␈α∩their␈α∪communes␈α∩are␈α∪found␈α∪repellent␈α∩by␈α∪the␈α∩media␈α∪or␈α∩the␈α∪majority␈α∪or␈α∩the
␈↓ ↓H␈↓emperor,␈α∪or␈α∪perhaps␈α∪they␈α∪are␈α∪some␈α∪kind␈α∪of␈α∪technological␈α∪hippies,␈α∪or␈α∪perhaps␈α∪they␈α∪are␈α∪the
␈↓ ↓H␈↓remnants␈α∞of␈α∞the␈α∞Red␈α∞Brigades␈α∞or␈α∞the␈α∞American␈α∞Nazi␈α∞Party.␈α∞ In␈α∞short,␈α∞whether␈α∞you␈α∞or␈α∂I␈α∞would
␈↓ ↓H␈↓regard them as heroic seekers or criminals fleeing just punishment, they may want to escape.

␈↓ ↓H␈↓␈↓ α_Whatever␈α⊃the␈α⊃reason␈α⊂for␈α⊃it,␈α⊃escape␈α⊃won't␈α⊂be␈α⊃very␈α⊃difficult␈α⊃for␈α⊂a␈α⊃group␈α⊃living␈α⊃in␈α⊂space
␈↓ ↓H␈↓already.␈α
 If␈αthey␈α
have␈αnuclear␈α
energy␈αand␈α
can␈αmake␈α
a␈αclosed␈α
eco-system,␈αthey␈α
can␈αreach␈α
the␈αstar␈α
of
␈↓ ↓H␈↓their␈αchoice.␈α They␈αface␈αtwo␈αproblems:␈α
their␈αsociety␈αmust␈αsustain␈αa␈αmulti-generation␈α
journey,␈αand
␈↓ ↓H␈↓the␈α∪new␈α∀solar␈α∪system␈α∀must␈α∪not␈α∪be␈α∀occupied␈α∪by␈α∀someone␈α∪willing␈α∪and␈α∀able␈α∪to␈α∀prevent␈α∪their
␈↓ ↓H␈↓settlement.␈α⊃ The␈α⊂more␈α⊃kooky␈α⊂societies␈α⊃will␈α⊃be␈α⊂transformed␈α⊃by␈α⊂a␈α⊃multi-generation␈α⊃journey␈α⊂into
␈↓ ↓H␈↓something␈α
more␈α"average".␈α
 The␈α
highest␈αimaginable␈α
exhaust␈αvelocity␈α
is␈α
the␈αvelocity␈α
of␈α
light,␈αand
␈↓ ↓H␈↓some␈αyears␈αago␈αmany␈αengineers␈αbelieved␈αthat␈αthis␈αwould␈αbe␈αthe␈αbest␈αrocket,␈αbecause␈αit␈αwould␈αgive
␈↓ ↓H␈↓the␈α∩highest␈α∪ultimate␈α∩velocity␈α∩of␈α∪the␈α∩rocket␈α∪for␈α∩a␈α∩given␈α∪expenditure␈α∩of␈α∪mass.␈α∩ Pessimistically
␈↓ ↓H␈↓inclined␈α∂scientists␈α⊂then␈α∂pointed␈α∂out␈α⊂that␈α∂the␈α∂a␈α⊂photon␈α∂rocket␈α∂must␈α⊂expend␈α∂enormous␈α⊂power␈α∂in
␈↓ ↓H␈↓order␈α
to␈α
provide␈α
a␈α
moderate␈α
thrust.␈α
 Indeed␈αa␈α
photon␈α
rocket␈α
with␈α
100␈α
tons␈α
thrust␈α
 and␈αargued␈α
that
␈↓ ↓H␈↓interstellar travel is impossible.

␈↓ ↓H␈↓ For␈α∞some␈α∂reason,␈α∞most␈α∂of␈α∞the␈α∞discussion␈α∂of␈α∞interstellar␈α∂communication␈α∞assumes␈α∂that␈α∞interstellar
␈↓ ↓H␈↓travel is impossible.  notes:

␈↓ ↓H␈↓1. can a multi-generation expedition succeed

␈↓ ↓H␈↓2. do we need an earth-like planet

␈↓ ↓H␈↓␈↓ α_What?  Go back in the well!

␈↓ ↓H␈↓3. Will civilization fission into pro- and anti-technology?

␈↓ ↓H␈↓␈↓ α_The bureaucratic ethic.

␈↓ ↓H␈↓4.

␈↓ ↓H␈↓John McCarthy
␈↓ ↓H␈↓Artificial Intelligence Laboratory
␈↓ ↓H␈↓Computer Science Department
␈↓ ↓H␈↓Stanford University
␈↓ ↓H␈↓␈↓ εH␈↓ 93


␈↓ ↓H␈↓Stanford, California 94305

␈↓ ↓H␈↓ARPANET: MCCARTHY@SU-AI

␈↓ ↓H␈↓␈↓εThis draft of galaxy[s77,jmc] PUBbed at 15:04 on May 28, 1978.␈↓