Conference noted::sf

    Re: 324. 128:
    
>>    What forces placed them in that narrow band are unknown.
    
    Cosmic Gaia!
    
    Re: Last few of 324

    I take it the 'tunneling' that is being referred to is the fact
    that if you reach, say, 99.9% c, your mass would be so great that
    you'd collapse into a quantum black hole; however, if you can
    control that collapsing enough to render a worm hole, you'll pop
    back out "elsewhen" -- is this correct?
    
                               Roak

    I don't offhand recall if there is any theoretical basis for
    tunneling per se. The idea comes from the fact that Relativity
    really only says that you can't travel *at* the speed of light.
    
    When you plug superluminal velocities into the equations, you
    get so-called "imaginary" numbers, which aren't really imaginary
    -- they're as real as any other number -- but we've never been
    able to "translate" them into observable physical phenomena. In
    theory, ftl isn't strictly impossible, but only beyond our
    science.
    
    Tunneling is a just an analogous idea to the quantum jump concept.
    Just as an electron can jump from a lower energy state to a higher
    energy state without ever being in any intermediary state, so is
    there a hope that an object can jump from an stl velocity to an
    ftl one without actually passing through c.
    
    --- jerry

    re: .1
    
    	Not exactly, bizarre things happen close to lightspeed, but
    you don't feel your increased mass (I don't think).  To take advantage
    of tunnelling, you would go up to say 0.5C and tunnel thru the barrier,
    suddenly you are doing 1.5C without having really gotten that close
    to C.  _Now_ it turns out that you have to expend energy to go slower,
    and you still can't get to lightspeed from this side either.  As
    long as your tunneller still works, you can get back when you have
    reached your destination, but what other effects you might experience
    are for now just guesswork.
    
    Willie

    	According to the excellent 1981 book, THE SCIENCE IN SCIENCE
    FICTION, although physicists do believe that wormholes exist, they
    are actually 300 billions times too *small* for even an electron
    to get through, so you can forget about a starship!
    
    	Larry
    

    Re .4
    
    Even if natural wormholes were too tiny for spaceships, a future
    technology might be able to engineer artificial ones that were roomier. 
    After all, natural light is hardly ever coherent, but that hasn't made
    lasers impossible.
    
    What is this book's estimate of the size of an electron, which, last I
    heard, was regarded as a point particle?
    
    Earl Wajenberg

    	I don't believe the book gave the size of an electron, though
    I'm sure any regular physics book does.
    
    	I have two questions for you:  How does one go about generating
    artificial wormholes, and even if they could be made, are we certain
    that "tunneling" through another universe would get a starship to
    another place in our Universe any faster than sublight speed?  Perhaps
    "hyperspacing" is actually *slower* than the sublight route, for
    which we can al least predict what will happen.
                
    	Larry
    

Re .6

Well, no, most regular physics books do NOT give the size of an electron. 
As I said, it's usually regarded as a point particle.  There are some 
fragmentary theories in quantum electrodynamics that give the electron a size 
of about 3 x 10-�� cm, but they're far from generally accepted.

Artificial wormholes most plausibly belong to a general technology of gravity 
manipulation.  That isn't practical under the present physical theories.  But 
if subsequent theories made it practical AND left most of general relativity 
in tact, there are a number of fun tricks to pull.  Wormholes are one, but 
there are others, and according to the math they would indeed be faster than 
slogging one's way through unwarped space.

None of this necessarily involves hyperspace, by the way.  Just warpings of 
normal four-dimensional spacetime.  We tend to think of the warped spacetime
as embedded in a flat space of higher dimensionality, and such might be the 
case, but it is not required by the theory.  Even if it were required by the 
theory, the starship in such cases would not leave spacetime for hyperspace -- 
not if we're talking wormholes or multiply connected spacetime or similar 
tricks taken from general relativity.

Earl Wajenberg

    Re 324.132:
    
    > Why does c=~300K km/s? Why not higher or lower?
    > 
    > That's the same as asking why pi=3.1415962... rather than 3 or
    > 3.5. It just *is* what it is.
    
    I wouldn't say that.  Pi comes from strictly logical operations; there
    is no connection to physics.  Count, define repeated counting as
    addition, define repeated addition as multiplication, find the
    operations that undo addition and multiplication, find a way to fill in
    the gaps (What is 3/4?  What is the solution for x*x = 2?), define the
    rate of change of a function (derivatives), and ask yourself what is
    the period of a function which is the negative of its second
    derivative.  Two pi.
    
    Pi cannot change in any conceivable universe, but c might.  So maybe
    there is some "explanation" for its value; some tie-in with other
    aspects of the universe.          
    
    
    				-- edp 

    > Why does c=~300K km/s? Why not higher or lower?
    > 
    > That's the same as asking why pi=3.1415962... rather than 3 or
    > 3.5. It just *is* what it is.
    
    >>I wouldn't say that.  Pi comes from strictly logical operations; there
    >>is no connection to physics.

    .
    .
    .
        
    >>Pi cannot change in any conceivable universe, but c might.  So maybe
    >>there is some "explanation" for its value; some tie-in with other
    >>aspects of the universe.          
    
    Ah, but this is precisely the example that caused me to ask the
    question...  Pi has the definition "the ratio of the
    circumference of a cirle to its diameter (yes, I know we use an
    infinite series expansion, but that's *not* the definition).

    Pi *is* tied to a physical characteristic - the curvature of
    space-time.  Pi is our familiar 3.1415... IN FLAT SPACE.  Einstein
    used the "Flatlander" analogy of two-dimensional beings measuring
    the circumference/diameter ratio on three 3-D manifolds... A
    plane, a spheroid and (I believe) some sort of hyperboloid.  The
    value of Pi is different for each of these curvatures, having our
    value only on a perfectly flat surface.  We are three-dimensional
    creatures living in a four (or higher) dimensional universe.
    Change the curvature of that universe (which coordinates? - beats
    me!) and you can change certain physical constants.  My question
    is "Is lightspeed dependent on some aspect of space(time) that
    can, maybe only theoretically, be modified?"

	Mike

    Re .9:
    
    > Pi has the definition "the ratio of the circumference of a cirle to
    > its diameter (yes, I know we use an infinite series expansion, but
    > that's *not* the definition).
    
    Specifically, pi is the ratio of the circumference of a circle in a
    plane to its diameter.  Pi is _not_ just the circumference of any old
    circle to its diameter.  So it does not change with the curvature of
    space-time.
    
    
    				-- edp

    Re: 10

    A 2D being cannot perceive anything other than the 2D manifold on
    which it resides - that is its perception of a "plane", and yes, its
    measurement of the ratio will be different.  Viewed from 3D, that
    same "circle" is warped in the third dimension by the curvature of
    the sphere, and the projection on a plane cutting through that
    sphere has a different diameter than the "diameter" the flatlander
    sees along the manifold.  This 3D diameter does indeed have the
    standard value of Pi given a flat 4D spacetime.  Try it at the
    bottom of a deep gravitational well, say a neutron star or a black
    hole (ignoring the event horizon) where theory says spacetime is
    grossly curved, and that constant may differ.  In our miniscule
    gravitational well any variance would be far too small to measure.
    

    re: .7
    
    > That isn't practical under the present physical theories.  But if
    > subsequent theories made it practical...
      
    This is the kind of thing that bugs me, it's not physical theories
    that make the universe the way it is, and the universe will not
    suddenly change to conform should we develop new theories!
                            
    If I were to develop a real FTL drive today in my spare time, nothing
    would have changed in the universe, but some theories might have to
    change to take the Smith Drive into account.  On the other hand, a
    theory pointing the way to the Smith Drive _doesn't_ meant that anyone
    would ever be able to build one.  In order to 'warp the continuum',
    do I stand in the middle and pull up on the edges, or do I need
    to hold it in a vice and hammer on the exposed part?
    
    Willie 

    We all know that the escape velocity of the earth is ~7 miles/second.
    
    Lets say that I take a spaceship out really far, beyond Pluto, and
    accelerate up to within 6 miles/second of the speed of light.  Lets
    say that next I direct my spaceship towards the earth and just ride
    the gravity well down.
    
    Q:  Won't I surpass the speed of light doing this?
    
    Sure I will become increasingly massive, but so what?  My attraction
    due to gravity to another object is independent of MY mass.  Well,
    you say, you will be going VERY fast, and will not actually be IN
    the gravity well very long.  Does not matter.  The velocity added
    to (or subtracted from) an object in a gravity well is independent
    of its speed or time in the well.  All that matters is how far out
    the well you start, and how far into the well you come.

    So, whats wrong with this picture?

    You mass so much that you are going to attract the earth.  Since
    it's falling into your gravity well, you don't get accellerated
    much....
    
    Willie

    In addition, the amount of time you'll be actually accelerated (or
    would be accelerating the earth toward you) is so small that you
    won't accelerate much.
    
                                   Roak

    Re .13
    
    No, you won't pass lightspeed doing that.  Diving into Earth's gravity
    well adds a flat 7 miles/second only as an approximation at low
    velocities.
    
    What diving down a potential well does is change potential energy into
    kinetic energy.  Kinetic energy = �mv�.  At low velocities, we are
    accustomed to treating the m, mass, as constant, so that increased
    kinetic energy shows up strictly as increased velocity.  As you
    approach the speed of light, however, velocity stops increasing so fast
    and mass starts increasing instead.
    
    AT the speed of light, velocity does not change at all.  (At least in
    special relativity.  I'm less certain about general.)  Light falling
    into or climbing out of a gravity well still moves at the speed of
    light, both ways, all the way.  But it changes frequency, that is to
    say energy, that is to say mass.
    
    Your near-light-speed ship diving in from Pluto would hardly change
    velocity at all, but would increase slightly in mass.
    
    Earl Wajenberg

    Re .12
    
    How do you warp the continuum?  As I said in .7, by gravity.  If the
    unification theories are true, any other force will work as well.
    
    Yes, thank you very much, I am well aware that theories do not change
    the way the universe works.  Allow me to put it in a less colloquial way:
    present theories do not make gravity engineering appear practical.
    Does this pass the board of censors?
    
    Earl Wajenberg

    Re .13:
    
    .16 is correct, but I want to make this point specifically:
    
    > The velocity added to (or subtracted from) an object in a gravity
    > well is independent of its speed or time in the well.
    
    That is false.  The energy change is independent of speed, time, or
    path in general.  The velocity change or just the speed change can vary
    quite a bit.  Even with Newtonian physics, if an object starting with
    zero speed fell into a gravitational well and ended up with seven units
    of speed, then an object starting with 10 units of speed and falling
    through the same path in space would end up with 12.2 units of speed,
    since 7^2-0^2 = 49 units of energy and 12.2^2-10^2 = 49 units of
    energy. 
    
    
    				-- edp

    Re .11:
    
    > A 2D being cannot perceive anything other than the 2D manifold on
    > which it resides - that is its perception of a "plane", and yes, its
    > measurement of the ratio will be different.
    
    A plane is flat and has nothing to do with any other two-dimensional
    surfaces that two-dimensional beings might reside in.
    
    You can define some other name to be the ratio of a circumference of
    something to the radius of the thing, but it is not pi. 
    
    
    				-- edp 

    re: .18  It's also marginally possible that things made of antimatter
    are attracted more strongly to normal matter.  Scientific American
    had an article in March about this.  [Side note, the March S.A.
    had several 'we haven't done the experiment yet and aren't sure
    when we will or if we can, but if we did, we would get results'
    articles in it.  IMHO, either drifting off into the fringes or
    publishing before anyone else can scoop them.....]
    
    re: .12
    
    > How do you warp the continuum?  As I said in .7, by gravity. If the
    > unification theories are true, any other force will work as well.
      
    I guess I didn't make my point properly.  I tend to approach these
    things from an engineering standpoint, instead of a theoretical
    basis of "well, theoretically if we [something] then we could maybe
    have [ftl/time_travel/free_lunch]".  Can _you_ build a supermassive
    rotating cylinder in your basement?  Yes, black holes can warp the
    continuum, but Sears has them backordered with no expected delivery
    date.  Where else are we going to get one?
    
>        present theories do not make gravity engineering appear practical.
>    Does this pass the board of censors?
 
    Perfect!  BTW:  The board of censors is just me, I didn't mean to
    get on anyone's case, but the implied fuzzy logic did bizarre things
    to my brain....
    
    Willie
    

    For those who sent mail requesting it, here's the section from
    Einstein on measuring Pi in curved space...

          From "Relativity - The Special and the General Theory
          - A Clear Explanation That Anyone Can Understand"
          by Albert Einstein (c) 1961 by the Estate of Albert
          Einstein published by Crown Publishers, Inc. New York.

          XXXI - The Possibility of a "Finite" and Yet
          "Unbounded" Universe

          But speculations on the structure of the universe also
          move in quite another direction. The development of
          non-Euclidean geometry led to the recognition of the
          fact, that we can cast doubt on the *infiniteness* of
          our space without coming into conflict with the laws
          of thought or with experience (Riemann, Helmholtz).
          These questions have already been treated in detail
          and with unsurpassable lucidity by Helmholtz and
          Poincare', whereas I can only touch on them briefly
          here.

          In the first place, we imagine an existence in two-
          dimensional space. Flat beings with flat implements,
          and in particular flat rigid measuring-rods, are
          free to move in a *plane*. For them nothing exists
          outside of this plane: that which they observe to
          happen to themselves and to their flat "things"
          is the all-inclusive reality of their plane. In
          particular, the constructions of plane Euclidean
          geometry can be carried out by means of the rods,
          e.g. the lattice construction, considered in Section
          XXIV. In contrast to ours, the universe of these
          beings is two-dimensional; but, like ours, it extends
          to infinity. In their universe there is room for an
          infinite number of identical squares made up of rods,
          i.e. its volume (surface) is infinite. If these beings
          say their universe is "plane," there is sense in the
          statement, because they mean that they can perform
          the constructions of Euclidean geometry with their
          rods. In this connection the individual rods always
          represent the same distance, independently of their
          position.

          Let us consider now a second two-dimensional
          existence, but this time on a spherical surface
          instead of on a plane. The flat beings with their
          measuring-rods and other objects fit exactly on this
          surface and they are unable to leave it. Their whole
          universe of observation extends exclusively over
          the surface of the sphere. Are these beings able to
          regard the geometry of their universe as being plane
          geometry and their rods withal as the realisation of
          "distance"? They cannot do this. For if they attempt
          to realise a straight line, they will obtain a curve,
          which we "three-dimensional beings" designate as a
          great circle, i.e. a self-contained line of definite
          finite length, which can be measured up by means of a
          measuring-rod. Similarly, this universe has a finite
          area that can be compared with the area of a square
          constructed with rods. The great charm resulting from
          this consideration lies in the recognition of the fact
          that *the universe of these beings is finite and yet
          has no limits.*

          But the spherical-surface beings do not need to go
          on a world-tour in order to perceive that they are
          not living in a Euclidean universe. They can convince
          themselves of this on every part of their "world,"
          provided they do not use too small a piece of it.
          Starting from a point, they draw "straight lines"
          (arcs of circles as judged in three-dimensional space)
          of equal length in all directions. They will call the
          line joining the free ends of these lines a "circle."
          For a plane surface, the ratio of the circumference of
          a circle to its diameter, both lengths being measured
          with the same rod, is, according to Euclidean geometry
          of the plane, equal to a constant value Pi, which is
          independent of the diameter of the circle. On their
          spherical surface our flat beings would find for this
          ratio the value

                                    sin(r/R)
                                 Pi ------
                                      (r/R)

          i.e. a smaller value than Pi, the difference being
          the more considerable, the greater is the radius
          of the circle in comparison with the radius R of
          the "world-sphere." By means of this relation the
          spherical beings can determine the radius of their
          universe ("world"), even when only a relatively small
          part of their world-sphere is available for their
          measurements. But if this part is very small indeed,
          they will no longer be able to demonstrate that they
          are on a spherical "world" and not on a Euclidean
          plane, for a small part of a spherical surface differs
          only slightly from a piece of a plane of the same
          size.

          Thus if the spherical-surface beings are living on
          a planet of which the solar system occupies only
          a negligibly small part of the spherical universe,
          they have no means of determining whether they are
          living in a finite or in an infinite universe, because
          the "piece of universe" to which they have access is
          in both cases practically plane, or Euclidean. It
          follows directly from this discussion, that for our
          sphere-beings the circumference of a circle first
          increases with the radius until the "circumference of
          the universe" is reached, and that it thereforward
          gradually decreases to zero for still further
          increasing values of the radius. During this process
          the area of the circle continues to increase more and
          more, until finally it becomes equal to the total area
          of the whole "world-sphere."

          Perhaps the reader will wonder why we have placed our
          "beings" on a sphere rather than on another closed
          surface. But this choice has its justification in
          the fact that, of all closed surfaces, the sphere
          is unique in possessing the property that all points
          on it are equivalent. I admit that the ratio of the
          circumference c of a circle to its radius r depends
          on r, but for a given value of r it is the same for
          all points of the "world-sphere"; in other words, the
          "world-sphere" is a "surface of constant curvature."
 
          To this two-dimensional sphere-universe there is
          a three-dimensional analogy, namely, the three-
          dimensional spherical space which was discovered by
          Riemann. Its points are likewise all equivalent. It
          possesses a finite volume, which is determined by its
                          2 3
          "radius" ( 2(Pi) R ). Is it possible to imagine a spherical

          space? To imagine a space means nothing else than
          that we imagine an epitome of our "space" experience,
          i.e. of experience that we can have in the movement
          of "rigid" bodies. In this sense we *can* imagine a
          spherical space.

          Suppose we draw lines or stretch strings in all
          directions from a point, and mark off from each of
          these the distance r with a measuring-rod. All the
          free endpoints of these lengths lie on a spherical
          surface. We can specially measure up the area (F)
          of this surface by means of a square made up of
          measuring-rods. If the universe is Euclidean, then
                    2
          F = 4(Pi)r ; if it is spherical, then F is always less
                     2
          than 4(Pi)r . With increasing values of r, F increases from

          zero up to a maximum value which is determined by
          the "world-radius," but for still further increasing
          values of r, the area gradually diminishes to zero.
          At first, the straight lines which radiate from the
          starting point diverge farther and farther from one
          another, but later they approach each other, and
          finally they run together again at a "counter-point"
          to the starting point. Under such conditions they have
          traversed the whole spherical space. It is easily seen
          that the three-dimensional spherical space is quite
          analogous to the two-dimensional spherical surface. It
          is finite (i.e. of finite volume), and has no bounds.

          It may be mentioned that there is yet another kind of
          curved space: "elliptical space." It can be regarded
          as a curved space in which two "counter-points"
          are identical (indistinguishable from each other).
          An elliptical universe can thus be considered to
          some extent as a curved universe possessing central
          symmetry.

          It follows from what has been said, that closed spaces
          without limits are conceivable. From amongst these,
          the spherical space (and the elliptical) excels in its
          simplicity, since all points on it are equivalent. As a
          result of this discussion, a most interesting question
          arises for astronomers and physicists, and that is
          whether the universe in which we live in infinite, or
          whether it is finite in the manner of the spherical
          universe. Our experience is far from being sufficient
          to enable us to answer this question. But the general
          theory of relativity permits our answering it with a
          moderate degree of certainty, and in this connection
          the difficulty mentioned in Section XXX finds its
          solution.

    What happens the other side of c? Do you have any mass.. Will gravity
    effect you?
    
    Chris

    According to the equations (someone will correct me if I'm wrong)
    you would have "imaginary" mass, time, length.  This means normal
    values multiplied by the square root of -1.  Exactly what this means,
    I will not even guess.
    
    				=ELB=

    	I thought the other side of c was d.
    
    	BA-DUM-BUM CHA! :^)
    
    	Seriously, folks, I don't know what kind of reality exists (or
    doesn't exist) in the realm of FTL speeds, but there are the
    theoretical particles called tachyons, which can *only* move (and
    therefore exist) at FTL speeds.  Their mass and energy become infinte
    as they *slow down towards* the speed of light and slower!
    
    	I bring up tachyons because their theortical behavior might
    give us some clue as to what life in the FTL lane might be like.
         
    	Larry
    

Re .24
    
To add to Mr. Klaes's description of tachyons, they have real-valued mass, 
length, and time as viewed by us, here on the low side of c.  In their own 
frame of reference, they have imaginary mass, length, and time, as suggested 
in .23.

What would that be like?  If you slip into hyperdrive by converting your ship 
to tachyons, what is it like for the yardsticks and clocks aboard the ship to 
give imaginary values?

No way to tell for sure, but consider this: Normally, any act of measurement 
can be viewed as involving a ratio.  If I measure a length, I take the ratio 
of the object's length to the length of my yardstick; how many times does the 
length of my yardstick divide into the length of the object?  If I measure a 
time, I take a similar ratio of a unit cycle on my clock to the interval 
being measured.

If both object and yardstick have imaginary lengths, it doesn't matter and 
won't show up, because the imaginary units divide out:  iX / i = X.

So life in hyperdrive might proceed quite normally.

Earl Wajenberg

    Sorry if this has been brought up earlier, but I will bring it up
    now:
    
    Does anyone know what causes Cherenkov radiation?  This is given
    off when an object travels faster than the speed of light in some
    medium (but of course not faster than light in a vacuum).
    
    Why is this effect observed?
    

	    			=ELB=

The encyclopedia I consulted spells it "Cerenkov" radiation and says it is 
due to the difference between the velocity of the particle and that of its 
associated electric and magnetic fields (which only propagate through the 
material at the local speed of light).  It is analogous to the shock wave 
produced by a sonic boom.

People have tried to detect charged tachyons by their presumed Cerenkov 
radiation, but without success.  Under that hypothesis, a tachyon would give 
off Cerenkov radiation and SPEED UP because it was losing energy.  (Remember 
tachyons move faster the lower their energy goes.)  Eventually, it would be 
moving at infinite speed and be completely out of energy.  But, since it would 
still be charged and still be moving faster than light, it would seem that it 
would have to keep on giving off Cerenkov radiation.

Also, its speed is infinite only in one particular reference frame.  In other 
frames of reference, its speed would be faster than light, but still finite.  
So how does it know how far to slow down?  Either tachyons can't be charged 
(or can't exist), or it is not valid to simply plug superluminal velocities 
into the conventional mechanics for Cerenkov radiation without further 
adaptation.

I suspect the last.  For instance, tachyons might have electric and magnetic
fields with no component in the direction of forward motion, but instead
components forward and backward in time.  That would probably screw up the 
Cerenkov mechanism.  (A temporal component to the field is not all that 
implausible for a tachyon.  Time travel is another of their tricks.)

Earl Wajenberg

    re .26 and .27 - I think it's a Cyrillic C, and is therefore pronounced
    "Ch", even if transliterated into English as a plain old C.
    
    len (who knows no Russian beyond da and nyet).
    

    Isn't it true that in the equations governing wave mechanics an
    imaginary component to a number (say voltage for instance) implies
    a phase shift?  Is there some way of interpreting a "phase shift"
    for matter traveling at superluminal speeds?  Is there an appropriate
    wave equation for matter?
    
    Wook

    Cherenkov radiation may imply a *creative* solution to the ftl riddle.
    
    If a particle is traveling ftl in the local medium it loses energy
    to obey the local speed limit. ie Cherenkov rad'n. If the particle
    was very big (ie the size of interstellar spacecraft) and was powered
    to compensate for the Cherenkov radiation loss, would it not be
    able to move indefinitely at supra-luminal speeds?
    
    Now quite how you get this particle to >c in the first place is
    the difficult bit!!!
    
    John
    
    

    Well, you don't get Cherenkov radiation in a vacuum, but other than
    that:
    
    1)	Use a focused beam of Cherenkov radiation as a drive, works
    just like a photon drive but different!
    
    2)	Another drive could be made by the use of a Cherenkov-laser-cannon,
    which would boost external payloads to FTL speeds.  Lessee, if you
    go FTL in a medium, you get Cherenkov radiation out, so conversely
    if you put Cherenkov radiation in you will go FTL.
    
    Before anyone flames me for pseudo-scientific hogwash, I don't believe
    it iether, but if you don't know what you are talking about, it
    sounds logical!  :+}
    
    Willie

Does a particle decelerate abruptly or at some rate when entering
a new medium with a slower velocity for light?
If abruptly, is there a problem with infinite rate of change?
If at some rate, is there a time when it first enters the medium that
it still exceeds the local c?
Is one possible answer that the boundary between media is not abrupt itself,
and that the transition is neither abrupt or in local violation?
If so, when is the Cherenkov radiation emitted?
Is it continuous along the track of the particle, or just at the
transition zone and spread from there?

- tom]

    Re .32
    
    The particle decelerates when it comes to the new medium.  While
    it is decelerating but still above the local speed of light, it
    emits Cherenkov radiation.  The energy of the radiation is supplied
    from the kinetic energy of the particle.
    
    Bear in mind that there is nothing uncanny about going faster than
    the speed of light in a material medium.  There is no "violation"
    of anything, anymore than going faster than sound "violates" something.
    Going faster than the speed of light in a vacuum is another matter.
    
    Earl Wajenberg

    Re: .33
    
    Our old friend *c* is the speed of light *in vaccuo*, correct?
    
    Is this one of these perfect vacuums that dont really exist, or
    is the ordinary kind just above all our heads?
    
    If its the perfect kind then why not consider a powered spacecraft 
    moving at greater than local *c* and realeasing Cherenkov radiation 
    as it goes? If as you say there is no problem then we ought to be
    able to go ftl. (As stated earlier how we get up to *c* is another
    question)
    
    If *c* relates to our own local vacuum then we're out of luck.
    Nice Try!!
    
    
    John
    
    

    
    

    Re .34
    
    Although the speed of light in, say, water or glass, is lower than
    the speed of light in a vaccuum, it is still hellishly fast.  And
    the speed of light in air does not differ significantly from the
    speed of light in a vaccuum.  As for interplanetary and interstellar
    space, the approximation to a perfect vaccuum is is so close, going
    faster than the speed of light in the medium but slower than c means
    going at just about c - 1 hair.  The problem now reduces to building
    what Ursula K. LeGuin called an NAFAL ship (Nearly As Fast As Light).
    Such a ship might leave an attractive trail of Cherenkov radiation
    in its wake, but it isn't really the hyperdrive ship usuallty wanted
    in SF.
    
    Earl Wajenberg

My wife found the following article in today's VOGON News:

<><><><><><><><>  T h e   V O G O N   N e w s   S e r v i c e  <><><><><><><><>

 Edition : 1708            Wednesday 30-Nov-1988            Circulation :  6405 

VNS MAIN NEWS:                            [Richard De Morgan, Chief Editor, VNS]
==============                            [Basingstoke, England                ]

    Science, Technology, Medicine, and Nature
    -----------------------------------------

    Here is the complete Electronics Weekly article on alleged "faster
    than light" electronic signals:

	Faster than light signals have apparently been observed in a simple
	electrical output circuit during a series of repeatable experiments
	which could spark one of the greatest scientific controversies of
	the century.

	The experiments and results are reported by the US instrument maker
	Alexis Guy Obolensky and Greek physicist Prof Panos Pappas in the
	december issue of our sister paper Electronics and Wireless World
	[Personal comment: I used to take this journal until a few months 
	ago: they seemed to publish quite a lot of screwball rubbish,
	although I am not discounting the above].

	If these observations are confirmed by further experiments, then 
	physicists will have to take a further look at the equations of
	both James Clerk Maxwell and Albert Einstein with potentially
	enormous implications from power generation to spaceflight.

	Obolensky claims to have made his measurements using a Tektronix
	2764 dual beam oscilloscope at the apex of a triangular circuit made 
	from 50 ohm co-axial transmission line connecting mercury vapour
	switches at each of the other two corners and a power supply on
	the baseline.

	He claims that when the switches are operated, the scope detects an
	almost instantaneous blip of power some 36ns before the main signal 
	arrives.

	Obolensky refused to be drawn into speculation about possible 
	explanations and implications. There are three possibilities:
	fraud, experimental error or a genuine breakthrough. The most
	likely error is common mode electromagnetic hum.

    [This is a rather poor report - I'll talk to the reporter and
    try and get some more detail. There is also a photograph of the
    scope display, but it doesn't make much sense to me].

    electrons flowing through coax move considerably slower than "c"
    (speed of light in a vacuum). What he is probably seeing is a radiated
    switching transient that propagates at nearly "c" through the air
    to the oscilloscope. 36 ns later the electrons arrive. BFD.
    
                                                   
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