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And now we're going to give an
even bigger, even former round
of applause for Alex and
Moritz, who's going to talk
about getting rid of nuclear
weapons, give it up to
other.
Thank you. Thank you.
Thanks.
Thanks, everyone, for joining us.
I'm Alex and this is Morritz.
And as he just said, this is a
talk about nuclear weapons.
Both Moritz and I and also our
colleagues back in Princeton
spent most of our time trying to get rid
of them.
But so far, we haven't made
much progress, especially lately.
In 2017 was
particularly difficult years.
But in this business, you're in for the
long haul. You have to be persistent
and you want to be ready when there are
new opportunities for
confidence building, arms control
and and nuclear disarmament
initiatives.
Now for this talk.
What's relevant is that any new
initiative toward further
reductions in the nuclear arsenals will
have to rely on robust
verification mechanisms.
And as you will hopefully see today,
verified verification.
We'll have to rely on trusted
radiation measurements.
After 25 years of R&D
in this area, no winning technology
has has emerged.
And ultimately it boils down to
a lack of trust in
the electronics that is being
used for these applications.
Samoyeds and I thought, well, perhaps
vintage computing platforms
may offer a new answer
to
to provide an answer to to
this challenge.
And so we brought some gear
and hopefully we'll demo it
in in a couple of minutes.
But before I get to this, let me just
briefly summarize
where we are today with regard to
nuclear weapons.
They remain there still remain about
15000 nuclear weapons today.
More than 90 percent of them are owned
by the US and
Russia. And then you see,
you know, seven other nuclear weapons
states in the world.
Unfortunately, these numbers actually
haven't come down by much over the
last 15 or 20 years or so.
And, you know, by any meaningful
standard, it's you know, it's a it's a
gigantic number.
I knew this year was
the North Korean last
latest test in September
where North Korea, for the very first
time, conducted a
test, a large nuclear weapons test,
250000 tons of TNT
equivalent. And we believe
this was a two stage thermonuclear
weapon. And it's significant in
many ways because
North Korea only tested, you know, five
or six nuclear weapons before that.
And it certainly now has a
credible nuclear capability.
And also the the
means to deliver this
weapon. We call it the peanut here.
You can see this typical shape for a two
stage weapon with a primary
and a secondary.
Now, in the interest of time, I will
not walk you through the
global consequences of a
a nuclear war,
even a limited one.
And they are pretty bad, as you might
imagine.
And personally, I believe, you know,
even a single nuclear explosion
in a major city,
what, you know, in many ways be
the end of the world as we kind of
know it and not in a good way.
Obviously, with a 200 kiloton
explosion, you could wipe out an
entire city in an in an instant.
Now, lately, there has been,
you know, quite some, you know, loose
talk about, you know, using nuclear
weapons. Again, we haven't seen this in,
you know, 20 or 30 years or so.
There is talk in Washington about
a preventive nuclear war
against North Korea.
And that is, you know, disturbing.
And I'm afraid there will be, you know,
more of this in in 2018.
And this tweet here kind
of summarizes the situation
quite well.
You can't lose the 2020 election if
there is no 2020.
However, there has also been some
positive developments this
year.
Early in the summer, 122
nations at the U.N.
in New York negotiated a nuclear
weapons ban treaty
which places nuclear weapons for the very
first time in the same category
as biological weapons, chemical weapons,
cluster munitions and landmines.
For obvious reasons, the weapon states
did not participate in these
negotiations.
But, you know, the idea is they will, you
know, join along the way
since we're here in Germany.
And I'm, you know, a citizen of Germany,
just as Morritz, it's worth
mentioning that Germany, too,
voted against the resolution
in 2016 to start
negotiations on on such a treaty.
I don't want to be, you know,
dwell on this too much.
I personally believe this is a mistake.
It would be the right thing to do
for Germany to join this treaty, and it
wouldn't be particularly difficult
for it for Germany to do so.
And, you know, just to close on
this and get it just earlier this month,
and this is you know, it is a big deal,
I can the international campaign to
abolish nuclear weapons received the
Nobel Peace Prize just for this
for this reason to facilitate the
negotiations of this treaty.
And you can see some of the key folks
who've been involved and kind of made
this treaty possible.
So this is really one of the highlights
of this year now.
But, you know, coming back to the purpose
and the topic of this talks and what is
to be verified, I already
mentioned it's it's going to be critical
to have verification mechanism in
place. It's particularly important
also for the ban treaty where you
try to verify, you know, the number zero.
And the United States, for example, has
actually made the point that the ban
treaty cannot be verified.
And for this reason, it should be
boycotted, which
is nonsense, of course.
But you get the idea.
People do take the verification question
very seriously
now to kind of highlight or illustrate
what it involves.
You have this cartoon here of a fictional
nuclear weapons state, has
a bunch of nuclear facilities.
Some of them are civilian.
And you may find them in other countries,
too, enrichment plants, reactors and so
on. Some of them are military
and they're highlighted here in blue.
And you know, the difference, the main
difference between the weapon state and
another weapon state is that the weapon
state, you know, has nuclear weapons and
they move around the weapons complex.
Right.
So they're trying to do is confirm
certain constraints on these on
these weapons limits on the number of you
know, and the number, again, could be
zero.
And the important challenges that
you have to resolve when you you know,
when you try to verify such a treaty.
And I highlighted them here on this
on this cartoon, we could give talks
about any one of them.
But today we want to talk about one
specific one that's typically considered
one of the maybe the most
difficult one to
to address, which
is confirming the authenticity of a
nuclear weapon.
So in a sense, the scenario is, you
know, the your counterpart,
the Russians, the Americans, whoever
shows up and says, look, we
have 100 nuclear weapons here, we want to
dismantle them and we want to get credit
for it for this. Right.
We want to kind of have these reductions
on the books. And how do you make sure
that whatever they present to you is
actually a nuclear weapon or a bunch of
nuclear weapons? That's the challenge.
And that's what we're trying to
solve today with vintage
verification.
So how do you do that?
So the first thing we need to know,
and it's really the only thing we need to
know, is that nuclear weapons,
any nuclear weapon contains fissile
material, nuclear explosive material.
And, you know, put the numbers here
on on the screen.
Typically, three to four kilograms of
plutonium, for example, is
enough where you could expect us in a
nuclear weapon. That that's about the
amount of plutonium you would
have in a nuclear warhead.
I was told this is aluminum.
And, you know, again, anything else
really doesn't matter too much for our
purposes. The key is it's plutonium
or highly enriched uranium.
Both of them are radioactive and we
can use this to detect
them from a distance.
Now, the issue is
so they have unique radiation signatures,
but they are highly sensitive and they
cannot be revealed to inspectors.
The only exception is really the one you
see here on the screen.
This is a bunch of us scientists,
actually some of our colleagues
in Princeton involved who went
to the Black Sea in 1989 and
made a measurement on a Soviet at the
time nuclear weapon and published
the Spectrum in in
Science magazine. And here you go.
It turns out you can actually learn quite
a lot from this spectrum.
So in the aftermath
of this exercise, weapons
states concluded, well, we cannot really
do this anymore. This was kind of a bad
call to go this way.
So in so then a couple
of new concepts developed and were
implemented to be implemented.
One of them in this in this
in this box over
there, the first one is,
OK, I can't possibly show you the
spectrum that you just saw.
So we have to kind of do it somewhat
differently. The first idea they come up
with is the attitude approach.
You said, OK, you cannot look at this
weapon, at this component.
It's in a container, but we can agree
on certain attributes.
So you sit down with the Russians and
say, well, you know, we have plutonium,
you have plutonium.
That's an attribute.
And both sides would agree.
OK, yes, we can you can confirm
that there's plutonium in this container.
That's one at. But maybe there's a
certain minimum mass, it has to be more
than one kilogram and we can do this also
with radiation detection measurements,
more than one kilogram, certain isotopic,
even the geometry or the size or the mass
you can detect with radiation
detection equipment.
So you make a list of attributes.
One approach, we don't really like
it particularly much because it's
it's obvious how you were defeated
because, you know, if the if the
threshold is set, that one kilo, I just
need to present, you know, one point one
kilos, it will always pass
the test.
That's one way to do it.
And the second one is the one we are
using here for this exercise of this
experiment is the so-called templated
approach. You do
acquire one radiation spectrum from
what we call a golden warhead reference
item.
You you store it perhaps in some
way.
And then when you go down the road,
the other side shows up where the second
item, you compare the two
signatures against each others.
And if they match, you say, OK, I accept
that the first one, I will also accept
the second one.
So that's a template approach.
And we'll do this later in a in
a moment.
So in both cases, you do acquire
sensitive information, right?
I mean, that the radiation detectors will
see everything.
So what you need is a third idea,
which is called an information barrier,
which is really just a piece
of electronic equipment that would do the
data analysis and then only display
kind of a red light, green light, you
know, pass, fail, go a no go
result.
It will not display the actual spectrum.
And that's the main idea of an
information barrier.
And coming back to, you know, why is
this, you know, such a difficult job?
The problem is how can both sides,
the inspector and the host team, trust
the technology at the same time?
OK, so the
the the host is worried that
this machine will accidentally release
the secrets right through some side
channel or so.
And the inspectors word
that the machine is actually not doing
anything meaningful and
will just display, you know, the result
that the host wants to see.
Right. So this is actually something
that the Russian nuclear weapons expert
said when he or she was invited
to a visit at a U.S.
weapons lab.
You know, you have some machine that, you
know, does something. You have no way of
knowing that this is actually a genuine
measurement.
So that's essentially where we are today
with, you know, the the state of the
technology.
Let me just wrap up here quickly before
we move into the demo part.
You know, why are they so hard to already
summarize some of this?
So first, this and it's very unusual
for an experimental physicist or so
that you actually don't know what you're
looking at except for the fact that, you
know, it's plutonium also.
So you cannot reveal you do not want
to reveal about what's actually in the
box.
Some information may be shared in
advance, but you certainly don't want to
learn anything else during the
inspection.
The second part is going to
be talking us, Russia, you know,
China and the rest of
them.
Your adversary has de facto infinite
resources, OK?
And the adversary may be,
you know, quite motivated to actually
defeat or deceive you
or your system.
And just as one data point, the US
is currently or refurbishing
one U.S. nuclear weapon to be 61,
much wealth.
Refurbishing that weapon costs
more than 30 million dollars.
One weapon, thirty million dollars, which
is more than the weight of gold
of that bomb.
So a government is willing to pay 30
million dollars to refurbish one weapon.
You might imagine how many how much
resources it may throw at
a system that might actually, you
know, pass fake nuclear weapons
as as genuine.
And then finally and
that's, you know, for this community in
particular, the most difficult one
or, you know, ironic one.
The host has lost ownership
of the inspection system before the
measurement.
So they walk away and, you know, you
don't know what they're doing with it.
And the inspector never again has access
to the system after the measurement
is complete because there may be some
form of classified
information left in the system.
So that's essentially why
these inspections are so hard.
And which is why we thought, you know,
can we offer an alternative with
with vintage technologies?
Now it's time for Morritz to proceed.
Here you go.
So as we heard, it's hard.
And if you look around who built such
systems, they actually have been less
than 10 built in the world, which is very
few for 25 years of development.
I'm going to introduce three and then
we're going to start up the the computer
that we have set up there, what is it
called? Trusted Radiation Identification
System or fortress built in the end
of the last millennium by the and.
Laboratories.
And this is how it looks like it's based
on the template approach, so it measures
sample and then compares this to an item
you want to inspect for this.
It uses a simple sodium detector.
It's a radiation detector, detects gamma
rays.
It's it's very rough in the spectrum
that it generates, but it's good enough
for the purpose.
It runs from a 12 volt battery
and it has something that's called a
trusted processor in this metal
enclosure. There's actually two
processors and some more hardware that's
installed in there.
And it doesn't have a green light, but it
has a display and a keypad.
So you control it by this keypad and you
display the result on the display.
And these small, little weird looking
things on the left of the picture, those
so-called eight buttons.
And one of them is actually used to store
the template. They're basically just, you
know, small memory things
you can plug into this trusted processor.
So what we like about the system
is it's very simple in its detector
setup. It's passive and it uses this low
resolution measurement.
So you don't generate too much
information that might then be
given to someone you don't want to give.
And it also uses a strong tempo
indicating enclosure.
So Sandia National Laboratory is actually
a pretty good in building these things
for a variety of purposes.
So this is this metal box
inside of this.
It's actually divided in two sides by a
big metal plate.
One side is called the red side.
The other side is called the black side.
And they only communicate through three
small holes by optical means.
So they actually completely electrically
separated. The right side handles the
classified data and the black side
deals with the display and the keypad you
saw.
And they also added special
tempered boards on the sides.
You see someone drilled a hole into this
and make any current measurements before
and after the measurement to see if
someone has failed with this metal
enclosure.
And the last thing we like probably on
the last but the last on this slide is
it's actually pretty fast.
So you can measure a template or an
inspection in 30 to 60 seconds
and then you take the spectrum,
condense it down to 60 numbers.
And only these 60 numbers are used to
compare it to another item
by a simple statistical test.
There are also some things that we don't
like. So we don't like that it actually
uses very complex hardware, even if this
is only in 586 and SDK
five processor inside on a PC
one A4 form factor board,
it still has four million transistors
that you would need to verify to make
sure it actually does what it's supposed
to do. It also uses an FPGA
for the data analysis.
And there's actually two of these
processor boards inside, one on the red
side, one on the black side.
Also, we don't really like that.
It's it's a system built only by a
nuclear weapon state in the United
States.
And its its main focus
was to ensure that no information is
leaked. But they actually also said
that this was their main focus.
So they had a hard time kind
of proving to the side that wants to
inspect that the system actually not
just only shows a green light or a good
sign on the display when when it's
asked to there's a
second system that's more recent build
actually by a nuclear weapon state, the
United Kingdom and
the non-nuclear weapon states, Norway.
They came together in the U.K.
Norway initiative for about ten years.
And they did two things.
One was they simulated
disarmament of nuclear weapons as
a kind of, you know, live action role
play. So they actually walked around with
warheads and measurement devices, not
warheads with fake warheads and
measurement devices and
try to figure out why this is hard.
But they also build an information
barrier.
And this is how it looks like this is
their third iteration.
They had two they built before, one by
UK and one by Norway.
And they go,
well, they had many goals to build this.
So they wanted to have a simple device as
simple as possible.
They wanted to use off
the shelf hardware.
They wanted to have it modular.
So you see, it's divided not
only by geometry, but also by color
into a digital board and analog board, a
low voltage board and the high voltage
board.
They want also to operate from battery,
that this operates from battery.
So it's independent of a power supply.
And they wanted it to be very robust
for use and they wanted it to be very
clear. Why are you using it?
So they came up with these three buttons
and then the middle circles
are green LEDs and the other ones are
red. So there's actually green lights,
but they set out to to
use the attribute approach.
So they didn't do the template approach,
but they tried to use the attribute
approach and the attributes they picked
for this device,
the presence of plutonium, a material
that you can use in energy weapon, and
the ratio between two specific isotopes
of plutonium, one plutonium 239
and one plutonium 235
240. Sorry.
And if this ratio was,
you know, above a certain threshold, it
would show a green light.
We like about this is the clear
operational procedure they have.
It's very simple user interface.
You think this is, you know, not that
important, but if you have a nuclear
warhead in the room, you want to make
sure that everyone knows what's happening
and there should be no confusion about
anything, basically.
They also had comprehensive
documentation. You can download
schematics of materials and
the software that ran on the machine on
on their website. It took them quite,
you know, a couple of years.
But then it's published now and we
actually learned a lot from this.
And last but not least, the most
important, this is actually a joint
design effort between a nuclear weapons
state and a state that does not have
access to nuclear weapons.
And they were aware of this and
analyzed also what problems they had
doing this.
Same here. What we don't like that much.
The system is based on the attribute
approach, which in general is harder
because you not only have to make sure
that two things are equal, but you
actually have to identify things from
everything else.
And so they use high purity
germanium detector.
Similarly, Gamarra detector, but
gives you a finer spectrum, which they
need. But it also requires to be called
by nitrogen, liquid nitrogen to
be very cold and it's not easy
to do in the field. They also need a very
complex algorithm in the box to say, OK,
there's plutonium present or there's no
plutonium present and they have the same
problem as before.
They, of course, used it.
There is no real open
chip, but they use a closed chip
for the data analysis.
They limited themselves also to a simple
chip, the Amiga 25, 16
and eight bit microcontroller for data
analysis.
When we looked at the schematics, we also
found this tiny microcontroller
on the so-called analog board and we
first surprised what this was.
But they said they use it for timing
issues, but just in a place where you
wouldn't expect any digital analysis.
But this shows this was for
us the first example to say, OK, you
know, there might be something going on.
Why is there a microcontroller where
there shouldn't be?
And they both have flash that probably
could store images that that might be
a problem.
The third example
we call information very experimental
or maybe something we built
we built two years ago.
We mostly built it because it looks
good and
also because we wanted something to to
learn kind of a prototype to actually see
what problems could we have and
as a mean to teach people to
how you would use this and how you would
build this. It's also a template
approach.
It can store up to three templates and
then measure an item and say,
you know, it's one of these three
templates and it also uses
sodium iodide, crystal, crystal
and scintillate as the Chrysostom.
This is how it looks like from the
inside. We try to make it very
transparent and also cheap.
It's cheap enough in quotation
marks is less than a thousand dollars.
On the left side, there's a single
computer.
On the right side, there is a custom
made board on the right picture.
You see when when it measures something.
And we also, in
a sense, ran into the same problem, we
use a complex chip.
So we use this sport.
It's called the reputation, which is nice
because it has this fast analog input
we use for for data acquisition.
But we can only do this if you have
an FPGA, basically because of the 14
bit under 25 million samples per second,
need to be processed fast.
And if you have a proper processor and we
run a full Linux stack for now
because it was just the simplest thing to
do.
So then we took a step back.
As I said, we say, OK, what what else can
we do? And we came up with the idea, OK,
let's try if we can actually do the same
with with hardware that is old, you know,
that's called a vintage verification.
That's the name we came up for it.
Why would you do that? You take the best
of all worlds and you try to build a
trust through simplicity
and probably also through through
obsolescence.
And we use a simple detector system.
Again, sodium iodide.
It's widely available.
It gives you the low resolution spectrum.
And then we use vintage computing
platforms. We use an apple to in this
case, which is is relatively
old. It has been reverse engineered even
if the specs haven't been published,
not all of them.
And it has been reversionary, quite good.
So it's quasi open source, that's what I
call it. And it's unlikely as someone
hit a back door or a hidden switch in the
system forty years ago for the Keys, that
it might be used for warhead verification
today. So we think this is not
very likely.
And another thing, we want to use this as
you would like to use the BYOB,
bring your own information barrier
approach where, you know,
the host country and the inspecting
country would go together and shop for
hardware basically either on eBay or go
somewhere and pick a device and use this.
And as
the processor inside of the apple to the
as the the 65 or two something we
also like very much, it still has
fewer transistors than there are nuclear
weapons in the world.
We hope to change this for the nuclear
weapons. It has only three thousand
five hundred ten transistors runs
usually at one megahertz, has fifty six
instructions.
But there's an abundant number of these
devices built. So the numbers vary
depending on who you ask.
But people say there have been billions
of these chips actually made and they
have been made from 1975 and they are
made more or less until today.
And these are five chips that we actually
had to to to play with.
And some of them are also in these arcade
machines and
in our living room.
And you see his kids testing our
verification processes if they
work good or bad.
And they also in the apple to it's the
14th anniversary this year, also the
Apple two. So the computer is older than
I am. And that made it a fun project
to to develop a radiation measurement
cards for this.
Why would we use that?
Why would you use an apple if you look at
Apple today, you think what's what's the
benefit of of
doing something with an apple?
But when this was developed,
I was actually, I think probably the last
time that a hacker ability or the ability
to extend your system,
one in the company policy over
seamless end to end user experience.
So when they developed this device, their
first home computer, it actually came in
an enclosure.
The two, Steve, Steve Jobs and Steve
Wozniak had a fight about how
many extension slots this device
would have.
Bosniac said it should have eight slots,
that people could do whatever they like.
You know, they could build cards, they
could build things, and they could
probably verify nuclear
warheads. At some point.
Jobs said they should only be to one
for a printer and one for a modem.
And that's enough. People want to do more
with that. So we are happy that
Bosniac one and you can see this
on the on the mainboard, this is a member
of an Apple TV, which is kind of
a slightly more advanced version
of the Apple two in
this case, forgotten the year.
I think it's from 82.
Yes.
This is a board from 82.
This is the board that's actually on
display here on the on the table.
And it has these eight expansion slots
and it also has some, you know, standard
computer hardware. It has the 65 two
processor and it has a ROM and
RAM. So we can start using it
without building our own computer.
In Syria, of course, you could just take
the 65 R2 and then
take some ram and some ram and mix
together and make the same
measurement. But that would be a
step further than just developing cards
for for the apple to.
And with that, I think it's time to
to actually turn it on for the first
time.
And Will, I hope it works.
We'll see.
I you can see this in, but anyone
can it on.
The floppy disk is not incertain,
start with this and
the floppy disk was missing it.
OK, here we go.
So we first we need to ramp the
high voltage.
The detective typically needs on the
order of a thousand volts,
and Moritz is going to walk you through,
you know, the details
of the boards. So now the high voltage is
up and we can acquire the
first template.
So we're fortunate.
Friends from Baucom brought us a
small calibration source
that we can sit in front of the detector.
So, you know, we can actually get the
signal.
And so we acquire the template.
And here we go.
Of course, in the actual measurement
setting, you wouldn't see this spectrum.
This is the thing you actually want to
have classified. But we saw it.
You know, it's more useful to show to
people here that this device is actually
acquiring data.
So this is a cobalt 60 source for those
of you, you know, who are not in
this business and people like Cobalt 60.
I mean, if you like radioactive sources,
I guess because this has it
has these two peaks that you can see and
it helps you really understand, you know,
the sensitivity or the resolution of
of your detector.
Anyway, this is going to count until two
to the 17th count, I guess.
Yeah. So we can go back to the
main screen if we let this run in the
background. We come back to this after
a while.
Probably Alex actually has to, you know,
push a button on the computer to
try. And there's one issue.
The detector has to warm up a little bit,
ideally would have to wait five minutes
or so to stabilize the high voltage.
So we'll see how we're doing.
We'll be doing on the on the verification
of the inspection in a few minutes.
OK, so what just happened?
Just a very quick
physics, one on one.
We had gamma rays coming from this
source. That's one type of radiation
and the gamma rays hit us. Scintillation,
crystal, that's something that
this shiny blue things.
So it's basically a material that absorbs
this gamma ray from the radiation source
and it emits other photons.
But photons that are more like standard
light and it emits about 38000
photons for a single gamma ray with
the energy of one MLV.
And these peaks at one point, two amoebae
and one point, I always forget the exact
number, but, you know, a little bit above
one maybe.
So all these photons get emitted in the
crystal and then they hit this
photo cathode, which sits at the end
of the crystal, and
they produce electrons.
And these electrons then get amplified
by something called a photomultiplier
tube, which is a tube where the electrons
get accelerated from the cathode towards
the anode. And on the way they hit these
curved surfaces, which
are called diodes.
And whenever they hit one of these, they
produce more electrons.
And when they end up at the anode, they
they one electron from the start is ten
million electrons on the node.
So it's a very, very efficient amplifier
for small signals.
And then the are is charged with a lot of
electrons.
But as we saw in the demo,
it needs high voltage.
And so we we designed a high voltage
board first and we
cheated a little bit on this year.
And we use the S.A.M.
arcane module, which produces
the high voltage for us.
We give this 12 volts and a set voltage
between zero and two point six volts.
And from this it makes proportional
one kilovolt up to one point six
kilowatts, 1600
volts. And we didn't want to play with
this voltages starting to,
you know, do electronics.
So we use this model but want to replace
this. And we build a very simple
digital to analog converter,
which you can see in the middle person
and out to our network.
And this gives us this VSAT
and it raises this over time to protect
the simulator.
And then, of course, we have to build in
data acquisition board a board that takes
the electrons that sit on the
anode this into this
B and C connector on the left process.
It will come to that in a second and then
give it to to an analog to digital
converter. We use a 12 bit flash ADC
that has luckily an interface
because the 65 two only has
a bit data interface and we have
some control logic and we actually also
have some LCD,
red, yellow, green and some blue ones.
But we decided for this demo that we
would not use them.
So in the analog
part of the board on the left, first you
get the signal.
It's pre amplified.
It doesn't mean it's amplified, but it's
something that sits in front of the
amplifier and it takes the charges
and converts them into a voltage pulse by
a charge sensitive up AMP circuit.
And you see, it's a fast rising pulse,
but it decays slowly over time.
So the next thing we do is differentiate
the signal by differentiating up stage.
And so the decay is shorter,
but then it gets inverted.
So we're using inverting stage.
We use an inverting stage to flip
it back up and also use a trim part
to adjust the game, because depending on
the build actually and the resistors
you used, you always have to adjust the
signal. So it actually fits in the the
ADC voltage range.
Then we do some pulse shaping.
It's to be noticed here that actually
the sculpture this is shot from our
oscilloscope, it takes a much wider
time range
and you see that the right time of the
poles now is slower.
And we did this to detect this pulse
easier and so fast rising.
We now have a relatively slow rising
pulse.
And then we feel this in the biggest and
most confusing stage, which is the peak
detect and hold area.
And it also does the ADC timing and it
will go through. The oscilloscope shot
this in detail.
The yellow line is.
A line of the actually of the output
of number one on the previous slide of
the charge, collecting up
stage the blue line, this is
what the peak detecting hold circuit
actually gives to the ADC.
And you see, this is very nice because it
rises up to the peak and then it holds
the voltage of the peak and gives
the ATC time to convert this.
And I forgot to mention,
of course, that the the height of the
peak is actually proportional to the
energy of the gamma ray that we detected
earlier.
So we hold this voltage for a while
and then we use the purple, which is a
digital signal produced by a
comparatively. We say, OK, when it raises
above a certain level, then we should
probably start this conversion and
then we wait a little while
until the signal is flat and then
we emit the green digital
signal to the ADC.
It's OK. Now you can start the conversion
and then if you look far to the right
of the picture, you see that
the signal goes down again.
And this is actually the time when the
agency has done the conversion takes
about 10 to 15 microseconds.
And the Apple two has read the two
words from the ADC and stored
them in channel in memory and also
increased the total counter that
counts the total number of events.
So there are some logic and
the whole process only takes about 60
microseconds.
And if you remember, it's a one megahertz
CPU and it leaves like 40 microseconds
for the processing. It means it's
actually 40 clock cycles.
And I guess if people would look at this,
they might even come up with faster,
simpler code.
But that's a reasonable time.
And we were surprised in the end how
fast we could actually sample
signals.
Before we go back to to another
demo, just
a few lessons I learned, I don't know how
many people in this room have built
hardware, probably, you know,
a few.
I I'm a physicist.
I did simulations most of my time before
I started doing this. So I didn't build
hardware. And then I set out to build
hardware for the machine that is older
than me. So how would you do that?
You actually start reading actual books.
So there is there's some manuals online,
but the best thing I did for this project
was to go on bookstore and,
you know, buy all books.
They actually cheap and they describe a
lot of things that happened in this
apple, too, and also
general things about electronics.
And then you have to design some things
and you have to try and you have to
repeat. And the best thing I figured
out was when I build
a breadboard, that doesn't work.
This is the breadboard where I set up the
ADC card.
When it doesn't work, the best is just
take a new one and start again.
And then, you know, probably it works
them and you have better ideas or you're
more awake because it's the next day.
And last for this,
it's important and it keeps you motivated
to choose a real world problem, and this
could be anything from, you know,
changing the heat or turning on and off
the light in your room, watering plans,
you know, having a guidance system fly to
the moon or getting rid of nuclear
weapons. And one of the benefits of
working on getting rid of nuclear
weapons, it's not a benefit, actually a
disadvantage.
The last year was bad and there were many
sleepless nights worrying about what
Trump and Kim Jong un might do.
So I couldn't sleep.
I could actually at least work on
something that might be useful.
And if you want to try this for yourself,
the software for the Apple is online.
There's also a repository for the
hardware. And if you don't happen to
have an Apple, too, which is probably
likely, there's also a repository
which has an emulator for the apple to
wear, added special emulation
for the cards we built.
So you can actually test out the software
loading the disk that we did just on your
normal Linux computer.
And now we go back to another
demo. Can we switch back to the.
There we go. OK, so here's our template.
So we could either now inspect the valid
item and not touch anything, or if we had
a second item, be
a second source, we could, you know, kind
of try and inspect the fake weapon.
Let me see. Let's do an inspection.
I'm not I haven't touched
the source if you watch me.
In the meantime, I actually acquired
a second template, kind of doing
it again, hoping that the high
voltage did stabilize
in the meantime.
So we're now inspecting we haven't
changed the warhead, so to speak.
So we hope it'll pass.
But I can't promise.
Do we have a second radioactive
source in the audience?
Let me see.
Here you go. Yes.
We're one of our friends was kind
enough to bring one along,
I can tell you. International air travel
with radioactive sources not recommended.
So we try to find them.
And in Germany, they are, of course,
completely harmless.
Let's just wait until this one finishes.
I can tell you when when you start
calling your friends, you know, look, I
need a radioactive source, I want to take
it to Leipzig, to the Congress.
People tell you, look, you know, I'm
sorry, I can't help you with that,
but some do.
So thanks for that.
So here we go again.
The code actually, most of the
the the software does the display,
which wouldn't be in the final version
of the software, so to speak, right now.
How many bytes that we have?
It's two and a half gigabytes, but most
of this is the display strings you see in
the code that actually display stuff.
OK, the
so let me put the check.
OK, Pass
Chi Square statistic Hex 12,
which will see that's actually pretty
good.
So now I have the second source.
Let me just throw it, you know,
somewhere on the table and
let's run another inspection.
I hit the three.
And well,
you can actually, I guess if you watched
the previous one carefully, you can
already see there's a new peak, you
know, showing up on the left
side. So, you know, it really should feel
about that by now.
Anything to add in the meantime, while
we're waiting, we can, you know, do the
the announcement basically if you if you
after this talk, there will be other
talk. So we have to leave the stage
quickly. But if you want to have a closer
look at the device, we're going over
to the school and we will be
at the forum.
Informatica Renford in freedon
area, which is on the first level, I
think, and we just set it up there.
So if you want to have a closer look at
this, you're invited to come over
and see.
We might not bring the resources just
for security or, you know, just
bring the device. And
just one thing, you know, in case I
forget it at the very end, I mean
and I'll wrap up in a moment.
But the one thing I think that we did
definitely show with us I know
is you the one megahertz processors
actually, you know, fast enough to do
this, right? I mean, we get about 2000
pounds per second, which is
actually not a bad number two for this
type of application.
And that's you know, that's
one megahertz chip is just enough.
So here we go.
It's complete. I hit the check
and it failed.
And if you see the Heckscher here,
it's pretty, pretty significant.
More, it's the machine language coding.
OK, can we switch back to the
the main screen?
OK, so I had
I could very briefly, in just
two or three slides, explain what the
code is actually doing, which is actually
the beauty of the template approach and
it's inspired by Tristes.
So here's a real world spectrum,
you know, looking a little fancier than
the ones you just saw, but basically the
same thing. Imagine yellow is
a valid item and orange is the invalid
item.
Here we have and you see there's one area
where there's kind of different,
but otherwise they look pretty similar.
The first thing we do is we divide it up
into a number of bins, a number
we pick 12.
But, you know, there's nothing special
about 12 small
number.
And then we take the average count in
these bins. So it's a very, very low
resolution spectrum, a histogram, if you
will, of of this
of this radiation spectrum.
And then we just compare yellow
versus orange and take the Chi Square
statistic for, you know, 12, 11
degrees of freedom.
And the nice thing is that, you know, see
the equation up there.
You know, you need to subtract two
numbers, multiply the difference and
divide by another number.
And you do this 12 times.
Even the machine language, you know, it's
pretty straightforward and easy to
implement.
And when you do this for this particular
example, you get for a valid
item the chi square off
around 10:00 and you see, you know,
distribution.
You can, you know, define OK, what is
green, what is red pass and fail.
And if you take the orange one, which,
you know, wasn't quite it wasn't very
different. But in terms of the square,
you know, it looks drastically different.
So and you're done.
You have a pass fail algorithm.
Pretty simple. So wrapping
up, you know, where do we go from here?
You know, can we can we actually turn
this into a viable device for
trusted measurement, you know, maybe
with the help of this community here?
So there's a bunch of things, obviously,
that we would have to do, you know,
revising the software and the hardware,
clean up the code.
There's a few things that we actually
haven't done yet. Subtract the
background, you know, correct.
For detector drift and so on,
replace the high voltage module, you
know, pretty straightforward.
We also probably want to package
the board or the whole equipment
in, you know, some type
of serious enclosure.
So that's robust against, you know,
terrorist attacks and so on.
But the one thing that is probably the
most important one, everything kind of
hinges on on that particular one for
this particular idea is, you know,
can we actually prove that
the the processor in this apple to
the 65 year FUTA is authentic?
It's genuine.
This one is actually was pulled from the
Tempest machine that you saw earlier
on the picture, but can be proof that the
processor is, you know,
is the real deal,
because if we can't, then we haven't
really, you know, won a lot.
So the apple to bought, you know, wasn't
the masterpiece.
It showed it already.
People have done amazing things with the
sixty five or two, you know, the visual
sixty five for Tuborg.
These are very high resolution optical
images of the of the day
built a transistor level simulation
of the sixty five or two.
It's kind of destructive analysis.
What we hope would be able to do is or
we ask can we do this in a nondestructive
way, not the simulation but
the imaging of the chip so
that you can actually confirm the
architecture of the original architecture
of of the chip because you want to use
the chip afterwards, obviously.
And we hope we can take advantage of the
fact that the the the
chip is made with
eight micron technology.
It's huge compared to what we
used today. It only has 2500
transistors and it's very, very well
understood.
We think there may be, you know, several
options to do this.
I mentioned the high resolution x ray
microscopy.
You know, ideally, you know, if we could
state the chip, you know what, the
package of the chip using some forensic
techniques, that would be fantastic
proof of provenance of of the chip
or perhaps even some, you know, logic
testing to confirm the original
architecture of the chip.
Again, we hope we can,
you know, leverage in some way the deep
understanding of the sixty five or two,
you know, at the transistor
level for this for
this purpose.
I think that's all we have.
We posted everything on vintage
verification, Doug, the slides,
the code, the hardware,
the hardware designs.
And as Mauritz mentioned, we'll be
outside if you're interested and, you
know, demo the hardware.
And with that, I guess we're happy to
take questions.
OK, so we have some time
for questions,
so please come closer
to the microphones.
Raise your hand and we'll take the
first one from the mike, number five
high.
And one question.
You said that you need to verify
the chip that's authentic.
Can you not do this afterwards after
you use the chip for the measurement
and do the destructive analysis
afterwards?
It's a good question.
My I think my answer would be probably
not. And because the damage would be
already done in a way, that's also why
you cut and choose approaches
where you put ten on the table and, you
know, just pick one and inspect the
others at home may not be good enough
for this type of application.
You know, if your your you know, the
other side would say, look, the risk is,
you know, after the fact, you learned
already our a weapon design and
it's kind of too late.
So ideally, we really want to do it
before we actually use it for the
inspection.
OK, thank you.
Now, no one piece
that was the.
Hi, thank you for the talk.
My question was about the
you you had stated that
you were concerned about side channel
potentially leaking some information
about the spectra or what you were
processing over. And I was kind of
wondering how you would address that with
a 65 Ojukwu.
That's probably the question we feared
from the audience.
We we basically we
haven't thought of this in detail and
of course, you would have many cyclones
in the 65 or two.
But at least that's my layman assumption,
is that if you can can run it from a
battery in a in an enclosure that
is R.F. resistant enough
that the system would be simple enough
that people would know all the floors and
protect against all the ways you could
actually get into the system,
ways that you would take a modern ship,
even if it's a simple chip.
You know that many of the talks that you
always find out afterwards that
actually there's a way to to listen in to
what the ship is doing
with the 65000 people have tried to do
this for 40 years.
We think this makes it secure than
not a foolproof, of course, but it makes
it secure. Then then you Chip.
Let's go to microphone number three.
Great talk with great toys.
I mean, what you what you did is you
made gamma spectroscopy available
with a much lower a cheaper,
simpler equipment than other people.
Do you also have an idea where to get
cesium or sodium
iodide since
a later material so that
you could do different spectroscopy
applications at home?
You can actually order sodium crystals
on eBay or online, and they've freely
available to everyone who wants them and
they're not even expensive.
And you can get the whole set of
CHRISTL with the photomultiplier,
which need to be light,
has to be blocked out.
So this is why it's silver shiny.
So all the light that is inside stays
inside and no light from outside hits the
photo. So you can buy these things
actually in old on eBay for,
you know, a couple of
a couple of, you know, 10, 20,
100, depending on where you get those
from dollars or euros.
That also does that also apply to a rat
poison, cesium, iodide,
thallium, thallium, doped?
I guess probably not. I haven't checked.
I wouldn't you know, I wouldn't know.
But this is why we like these detectors.
I mean, they're really there's nothing
more abundant than this type of detector.
You you know, you can you can find them
on eBay and they're really affordable.
Thank you.
No more questions.
Step up to the microphones.
And microphone three, thank you.
Have you gotten in touch with
was at all or have you wanted to or
needed to
meet with Steve Wozniak?
Yeah, not yet.
Maybe after this talk.
I mean, literally, if you knew when we
finished this project, you know,
kind of just a few hours ago, so to
speak, but now we have something that
actually works. And I'm not actually sure
what we would ask him, but I hope you'll
like it.
Well, thanks.
OK, more questions,
we still have a little bit of time, maybe
for one more question,
it can run more inspections if you want
to.
OK, so someone's coming up microphone
one. So thank you very much for the talk,
maybe a very naive question,
but what is secret on the spectrum?
What can you learn from a spectrum?
It's not a sip of Coca-Cola, I guess.
Yeah, I have to go back all the way to
the beginning,
but, you know, I mean, you could make the
argument and I think it's it's a valid
one. I mean, it's something especially
from a non weapons said you should ask,
you know, and, you know, what's the
what's the big deal about your secret?
You know, it would be so much easier.
It's a true statement of obvious
statement. If you reveal the secret,
then, you know, we wouldn't have to
protect it.
And, you know, it's always worth asking,
you know, what exactly do we
have to protect if we
you know, it kind of a middle ground here
is we believe that these 12 numbers,
they may be just on the edge where
a weapons, they might say, look, you know
what, these 12 numbers for the you know,
the template for this particular weapon
type, we might as well put them out
there.
And we don't have to protect the
template. That would be a
big deal. But in general, the idea or
the the
concern would be that you, as you can
actually learn, you know, more
or less the design of that particular
weapon. And, you know, they are weapons.
So, you know, people trying to defend
against them.
So, you know, your
adversary might learn exactly,
you know, how you designed your weapon
and may actually come up with an idea
to defeat it.
And again, I'm not subscribing
to this, you know, viewpoint, but, you
know, that's obviously something that
people would bring up. And, you know,
weapons states have invested billions
of dollars into this technology and
because they think they need it and they
will protect the secret.
But the question about revealing the
secret is a very important one.
And, you know, we shouldn't just take it
at face value. Yes.
You know, we have to protect, you know,
every secret that you say is a secret.
And I think the argument, if
you actually give us you know, if you're
being more transparent about certain
things, the verification part
gets so much easier and maybe less
intrusive. And it could be a win win
at the end of the day.
But of course, the recipe for Coca-Cola
would also be pretty important.
I'm sorry.
Never mind.
OK, OK.
That was the last question.
We are out of time, unfortunately,
but give a huge round of applause
to come on March from
Princeton University, getting rid of
nuclear weapons.