if the "rings" of the spiral of the coil are not closed but open to
the side where the space stones are coming, we can't produce the
magnetic field to hold the plasma and it will vent to space.
another huge problem: even though the plasma vaporizes the incoming
stone the conservation of momentum still means this burning steam of
what used to be stone will hit and penetrate your ship.
next Kaku talks about lasers, making a lases beam crisscross the
surface of the spaceship using mirrors.
this suffers from all the above downsides: energy for the laser, one
mirror broken by the first spec, and then rest are useless, the
burning steam will still hit the ship etc.
next Kaku taks about physically armoring the spacecraft with nano
carbon tubes. today they are very very expansive and small, but
let's say that in the future they are available:
it would be like a car accident in an old car that doesn't absorb
the energy of the collision. the vehicle will survive, but it will
pass all the energy to the crew which will die.
Kaku illustrates with swinging golf balls into a chain-link fencing.
but in his metaphor the the fence has posts set into the ground
(made of steel tubing). this transfers the energy to the ground.
in the real case whatever holds the net in space will not to be
rigid so it will transfer the energy of the impact to the spaceship.
How Do Star Trek’s Deflector Shields Work? (Because Science w/ Kyle
Hill) - skip to about minute 2:30 .
Kyle suggests deflecting incoming things that have electric charge
using Lorentz force.
this idea is mostly good - it solves most of the problems that arise
in Kaku's "solutions".
Kyle doesn't explain what's the shape of the spaceship in order to
create this field so i will assume the best one i can think of (for
the required magnetic field) - a torus (doughnut or bagel shape).
there is no impact at all, no hot vapor with enough momentum to
penetrate the ship and no "stiff" non-absorbing crash.
the magnetic field extends outside the spaceship so it doesn't
suffer from the "closed container" problem of the plasma.
where do you get the energy to flow electric current around the
torus (doughnut) for so long?
maybe instead of an electromagnet we can use a permanent magnet but
then it will be so massive that you can't accelerate it and
decelerate it (let alone fight a planet's gravity).
another huge problem that is discussed in the video: "what if they
have a neutron bomb?", or in other words, the magnetic field doesn't
effect objects that don't have an electric charge.
not just neutrons, any object that doesn't have a "net" charge,
because it has roughly as many positive and negative particles, this
includes all space rocks!
can we "put" electric charge on the incoming object?
The ancient Greeks noticed that amber attracted small objects when
rubbed with fur. the Greek word for amber is "electron" (ἤλεκτρον).
but even if we can rub off some electrons from the incoming object
it's only on the surface so that's not enough.
can we "give" the object a bigger electric charge?
maybe in the front center of our spaceship we can have an electric
rod like when people do demonstrations with a tesla coil, that will
shoot lightning at whatever is coming?
this will work only if that object is conducting electricity, and
even then not always, because if the object is conducting all around
(like a metal rock), it's indise is in a Faraday's cage.
so maybe if we can't effect the inside we can effect the outside?
what if can add to each incoming object something with electric
it's not like we have an incoming letter and put it in an envelope,
these things might come close to the speed of light. so what we need
it a very tough "cup" that will catch it.
this "catcher" can be made from a strong metal like titanium which
is very expensive especially considering we can't collect it back
after it's deflected.
but we can't just put one little "catcher" because we don't know
where the incoming object will be. we also don't know what size the
incoming object will be.
so we end up arranging something that looks like a hierarchy of
"catchers" in layers: the front most layer has many small "catchers"
the size of drinking glasses on a tray. the next layer has fewer but
bigger "catchers" the size of buckets. the next layer had even fewer
but even bigger "catchers" the size of open barrels. and so on.
let's say a tiny meteorite is incoming, it will be catched by one of
the cups and because of the spaceship's magnetic field it will be
gradually pushed aside away from the spaceship.
this method also has problems of its own: the layers that are far
from the magnet are in weak magnetic field, and also a catcher can
flip and "drop" its content (the object) in the direction of the
if the object comes exactly in front of the ring, there will zero
deflection because it will be pulled equally to the left and right
etc, and it will destroy the spaceship.
this is a low probability scenario but if it happens it's
catastrophic - like breaking one mirror in the laser scenario we
my solution uses the "catchers" system but instead of Lorentz Force
that deflects, i use Lenz's Law which works like in the following
two videos by MIT and "Sixty Symbols":
so the whole spaceship will be a long tube made of copper.
More Magnets - Sixty Symbols
or the whole spaceship will be a long aluminum tube:
Physics Demo -- Lenz's Law
and because of the currents that are induced in the tube it will
slow down the "catcher" that contains the incoming object.
now the "catcher" doesn't need to have electric charge, but instead
the catched needs to be a magnet. for example neodymium magnets.
this method keeps has all the advantages of the "Lorentz Force"
method, but doesn't have that method's disadvantages:
it doesn't need energy, it's totally passive; we collect the
"catcher" after it slowed down the incoming object so the catcher's
cost is not important because the catcher is recycled; the "catcher"
has no reason to flip because there is no rotation moment because
all the forces act along the same line which is along the tube; and
finally if the object comes exactly in front of the ring it's still
after the incoming object was slow down considerably by the Lenz's
Law, if it didn't stop completely, it is caught by the next layer of
we can make the tube very long, as long as calculations of worst
case scenario will show that is needed.
at the back side of the tube will live and work the crew.
AFTER THE IMPACT:
after each colission with a space rock the spaceship must reset the
"catchers" to their initial location.
i think this means the spaceship has to slow down and stop
mechanically move the catchers back into place. since the crew move
them slowly there is not a strong force working against the crew.
by the way this elongated shiny shape might be the shape of part of
the UFO sightings that look like a cigar!