**Noesis**

**The Journal of the Mega Society**

**Number**** 84**

**August 1993**

**EDITORIAL**

**5139 Balboa Blvd #303**

**Encino CA 91316-3430**

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**IN THIS ISSUE**

**ARTICLE BY MICHAEL PRICE**

**LETTER AND AD FROM KEVIN SCHWARTZ**

**LETTER AND ANALOGIES
FROM MARCEL FEENSTRA**

**TRAVERSABLE WORMHOLES: SOME
IMPLICATIONS
or
CONTACT! A POST-SINGULARITY PHASE CHANGE
**

Copyright (C) Michael Clive Price, June 1993 email: mcp@price.demon.co.uk (Internet)

Steven Weinberg

Everything will be accomplished

Gerald Feinberg

"You must

Opening words of the Time
Traveler, from _The Time Machine_, by HG Wells

Summary: Traversable wormholes permit FTL travel,
within general relativity, but not time travel and associated acausal

0. INTRODUCTION

To establish an interstellar trading civilisation we need

The article is structured thus:

0. INTRODUCTION: You're reading it.

1.

2.

3. TRAVERSABLE WORMHOLES: The latest candidate for FTL, and

4. EXPLORING THE UNIVERSE: How to explore the universe with a modified
Bussard ramscoop and on-board wormhole.

5. TIME TRAVEL: Why traversable wormholes do not permit time
travel, but allow FTL, and remain compatible with relativity

6. EMPIRE-TIME: The differences

7. ALIENS:

8. UNIVERSAL TIME: ... a universal simultaneity, creating a
post-Singularity phase

9. BEYOND THE OBSERVABLE UNIVERSE: Implications of exploring beyond the edge of
the observable universe.

10. BASEMENT UNIVERSES:

11. CONCLUSION

12. ACKNOWLEDGMENTS

13.

14.

1.

We can colonize the universe at sub-

Nanotechnology [4]

With

Interstellar

Trade routes, we have seen, are unlikely to spread beyond single star systems,
at

2.

Life, on the galactic scale, becomes incredibly

What stops FTL travel? According to
relativity as an object accelerates towards the

Since the advent of relativity there have been a

1) Tachyons: Tachyons are posited FTL particles,
compatible with relativity.

2) Superluminal quantum

3) Spinning black-holes: Things looked hopeful for a while

4) Einstein-Rosen bridges: An Einstein-Rosen bridge connects two
otherwise widely

As each

3. TRAVERSABLE WORMHOLES

In 1985 Carl Sagan appealed to theoretical physicists for

In 1989 Matt Visser

The 'exotic' nature of the edge

The negative energy of a wormhole has equal magnitude to the energy of a
black-hole, where the wormhole throat radius equals the black-hole
Schwarzschild radius. A traversable
wormhole can be

Negative energies,

Construction of 'exotic' cubes is, of

Wormholes can be viewed as

These two properties of wormholes, fixed matter-throughput versus bandwidth
scaling with mass or radius,

An object swallowed by the mouth of a wormhole leaves

4. EXPLORING THE UNIVERSE

Wormholes enable travel from

To sustain

At the relativistic speeds time dilation becomes a major factor. Time dilation reduces trip times for
relativistic travelers. A probe
accelerating at

Destination Distance
in

Alpha Centauri 4.3 2.3
years 3.3 days

Centre of Milky Way 30,000 11
years 6.5 days

Andromeda Galaxy 2,250,000 15
years 8 days

Nearest Alien Civilisation? 100 M 19
years 9.5 days

Edge of observable universe 10,000
M 24
years 11 days

Edge of inflationary bubble? 10^30 70
years 28 days

The probe remains in

An

Road, sea and air routes allow the creation and operation of global
markets. With the growth of
transportation once isolated economic zones are now forming more tightly
integrated global trading blocs.

5. TIME TRAVEL

As we have seen, wormholes are constrained by relativity to travel at sublight
speeds, being time-dilated as normal.
Clocks placed at the two mouths of a wormhole always remain in
synchronisation with each other [19]. If
I look

6. EMPIRE-TIME

Wormholes do have

The time frame being defined by the expansion of wormholes, which I've dubbed
empire-time, is not coincident with the cosmological time frame. The cosmological space-time is the space-time
frame in which the

Wormholes sent to the Andromeda, in our example, at near

Empire-time is the time imposed by the wormholes throughout the region

Once the empire-time frame has been defined it becomes increasingly difficult
to

Questions about the distant cosmological future of our universe are

7. ALIENS

Enrico Fermi said "if aliens existed

A statistical elaboration of this argument [25] gives grounds for

With relativistic probes and on-board wormholes,

This opens up the possibility of

A well coordinated, centrally controlled species might halt expansion at the
boundary of their home galaxy (say) for a few thousand empire- years, building
up

A more likely scenario is:

Empire-times merge as empires merge.
Clocks in

8. UNIVERSAL TIME

This is a symmetrical situation. Not

After

Universal time has many similarities with absolute time, as Newton conceived of
it [26]. Newton viewed absolute time as
deriving from God's immanence, or

Roughly half the civilisations we meet are likely to have been around, in
cosmological terms, hundreds of millions or even billions of years before
us. Gaining

9. BEYOND THE OBSERVABLE UNIVERSE

The expansion of the universe is defined by a parameter called Hubble's
constant, which relates the distance of a far galaxy with

Inflationary

A

10. BASEMENT UNIVERSES

Initially, no doubt, wormhole connections would supplement existing
architectures, connecting together points in the existing locally Euclidean
universe. The next logical step would be
to start constructing extensions to the existing topology. The

We have already mentioned

In a

This might seem somewhat

11. CONCLUSION

We have seen

From a more detached point of view it is

12. ACKNOWLEDGMENTS

My thanks to all the Extropians and Cryonauts for their feedback,

13.

[1] Gerald
Feinberg. Physics and Life
Prolongation. _Physics Today_ 19(11) 45
(1966). The

[2]

[3]

[4] K Eric Drexler. _Engines of Creation_, Anchor
Press/Doubleday, (1986) ISBN 0385199724. _Nanosystems: Molecular Machinery,
Manufacturing, and Computation_, Wiley-Interscience, (1992) ISBN
0471575186. See also _Extropy_#10 4(2)
44 (1993) for a review by J. Storrs Hall

[5] Hans Moravec. Pigs in cyberspace, _Extropy_#10 4(2) 5
(1993)

[6] Gerald Feinberg. Possibility of

[7] Charles Bennett. Teleporting an Unknown Quantum State via Dual
Classical and Einstein-Podolsky-Rosen Channels.
_Physical Review Letters_ 70, 1895 (1993) How to

[8] Werner Israel & Eric
Poisson. Internal Structure of
Black-Holes. _Physical Review D_ 41(6)
1796 (1990) Infalling radiation (

[9] Charles W Misner, Kip S Thorne &
John A Wheeler. _Gravitation_ WH Freeman (1973) ISBN 0716703440. Simply the best book on
general relativity. See section 31.6 for
Einstein-Rosen bridges.

[10] Carl Sagan. _

[11] Michael S Morris & Kip S Thorne.
Wormholes in Space-time and Their

[12] Matt Visser. Traversable Wormholes:

[13] Ian H Redmount & Wai-Mo Suen.
Is Quantum Space-time Foam Unstable?
_Physical Review D_ 47(6), 2163, 15-March-1993 The authors

[14] Thomas Schneider. Channel Capacity
of Molecular Machines. _Journal of
Theoretical Biology_, 148(1) 83 (1991) Draws the

[15] Claude L Shannon.

[16] Thomas Schneider. Energy
Dissipation from Molecular Machines.
_Journal of Theoretical Biology_, 148(1) 125 (1991) A general derivation
of the thermodynamic

[17] Ian Nicolson _The Road to the
Stars_, Westbridge Books (1978), ISBN 0-7153-7618-7 Has

[18] RW Bussard. Galactic Matter and
Interstellar Flight. _Astronautica Acta_
6 179 (1960)

[19] Fernando Echeverria, John Friedman, Gunnar Klinkhammar, Michael S Morris,
& Ulvi Yurtsever. Cauchy

[20] EV Mikheeva & Igor D Novikov.
Inelastic Billiard Ball in a Spacetime with a Time Machine. _Physical Review D_ 47(4) 1432 15-Feb-1993 An
extension of [19] which covered the

[21] Stephen W Hawking. Chronology
Protection

[22] Matt Visser. From Wormholes to Time
Machines: Remarks on Hawking's Chronology Protection

[23] Gary W Gibbons & Stephen W Hawking.
Selection Rules for Topology

[24] Enrico Fermi, quoted by Carl Sagan.
_Planetary and Space

[25] Dani Eder (private

[26] Sir Isaac Newton. On the Gravity
and Equilibrium of Fluids (1668+) Translated in _Unpublished Papers of Isaac
Newton_ ed AR and Marie Boas Hall (1962) Newton preferred the term Universal
Ruler to describe God. The divine
time-frame was the Universal Ruler's view of

[27] Thomas Roman. Inflating Lorentzian
Wormholes. _Physical Review D_ 47(4),
1370 15-Feb-1993 Speculation on inflating planckian wormholes to macroscopic
and astronomical dimensions. Also

[28] Andrei D Linde. An Eternally
Self-Reproducing Cosmos? _Scientific
American_, 268(5) 10 (1993) Computer simulation of

[29] Dalia S Goldwirth & Tsvi Piran.
Inflation - an Alternative to the Singular Big Bang. _General Relativity and Gravitation_ 23(1) 7
(1991) More detailed presentation of eternal inflation [28], and how it may
arise from quantum gravity, based on generic, dimensional arguments. Habitable post-inflationary bubbles

[30] Matt Visser. Wormholes, Baby
Universes and Causality. _Physical
Review D_ 41(4) 1116 (1990) Banning topological transformations preserves
causality. Baby universes created by
inflation, for

[31] Katherine A Holcomb, Seok Jae Park & Ethan T Vishniac. Formation of a "child" universe in
an inflationary cosmological

[32] Alan H Guth, SK Blau & EI Guendelman.

[33] Jacob D Bekenstein & Marcelo Schiffer.
Proof of the Quantum Bound on Specific

[34] Jacob D Bekenstein.

[35] Freeman J Dyson. Time without End:
Physics and Biology in an open Universe.
_Reviews of Modern Physics_, 51(3), 447 (1979).

[36] Gary T Horowitz. Topology

[37] Robert P Geroch. Topology in
General Relativity. _Journal of
Mathematical Physics_ 8(4) 782 (1968) Creation of a wormhole requires either
CTLs or a "mild" [36] singularity, according to classical general
relativity. If we exclude CTLs, a la
Visser, then wormhole creation implies a mild, physically permissible,
singularity.

14.

Apart from the

Paul Halpern. Cosmic Wormholes: The
Search for Interstellar Shortcuts.
Dutton Press (1992) ISBN 0525934774.
Very good presentation of the arguments against time-travel and FTL

John Gribbin. In Search of the Edge of
Time. Black Swan (1992) ISBN 0552994626. Covers a lot of the relativity

Thomas Donaldson. The Holes of
Space-Time. Analog

**LETTER BY KEVIN SCHWARTZ**

[Editor's comments:
Send dialogue on time travel.
Here's Harding's

**AD (?) FROM KEVIN SCHWARTZ**

[Editor's comment on next
letter: The GRE is a test people

Under the semester system, a
student is (was)

**A LETTER AND A TEST FROM MARCEL FEENSTRA**