Batavia, Ill.— Scientists of the DZero collaboration at the US
Department of Energy’s Fermilab have announced the observation of pairs
of Z bosons, force-carrying particles produced in proton-antiproton
collisions at the Tevatron, the world’s highest-energy particle
accelerator. The properties of the ZZ diboson make its discovery an
essential prelude to finding or excluding the Higgs boson at the
Tevatron.

The observation of the ZZ, announced at a Fermilab seminar on July
25, connects to the search for the Higgs boson in several ways. The
process of producing the ZZ is very rare and hence difficult to detect.
The rarest diboson processes after ZZ are those involving the Higgs
boson, so seeing ZZ is an essential step in demonstrating the ability
of the experimenters to see the Higgs. The signature for pairs of Z
bosons can also mimic the Higgs signature for large values of the Higgs
mass. For lower Higgs masses, the production of a Z boson and a Higgs
boson together, a ZH, makes a major contribution to Higgs search
sensitivity, and the ZZ shares important characteristics and signatures
with ZH.

The ZZ is the latest in a series of observations of pairs of the
so-called gauge bosons, or force-carrying particles, by DZero and its
sister Tevatron experiment, CDF. The series began with the study of the
already rare production of W bosons plus photons; then Z bosons plus
photons; then observation of W pairs; then WZ. The ZZ is the most
massive combination and has the lowest predicted likelihood of
production in the Standard Model. Earlier this year, CDF found evidence
for ZZ production; the DZero results presented on Friday for the first
time showed sufficient significance, well above five standard
deviations, to rank as a discovery of ZZ production.

“Final analysis of the data for this discovery was done by a
thoroughly international team of researchers including scientists of
American, Belgian, British, Georgian, Italian and Russian
nationalities,” said DZero cospokesperson Darien Wood. “They worked
closely and productively together to achieve this challenging and
exciting experimental result.”

DZero searched for ZZ production in nearly 200 trillion
proton-antiproton collisions delivered by the Tevatron. Scientists used
two analyses that look for Z decays into different combinations of
secondary particles. One analysis looked for one Z decaying into
electrons or muons, the other decaying into “invisible” neutrinos. The
neutrino signature is challenging experimentally, but worthwhile
because it is more plentiful. In the even rarer mode, both Z bosons
decay to either electrons or muons. Just three events were observed in
this mode, but the signature is remarkably distinctive, with an
expected background of only two tenths of one event.

Sourced from Fermilab Press Room

Many
of us have been fascinated by the concept of absolute zero, the
temperature at which everything comes to a complete stop. But physics
tells us otherwise: absolute zero cannot be reached but only
approached, and the closer you get, the more interesting phenomena you
find!

Three outstanding scientists from ESF’s EUROCORES
Programme EuroQUAM gave insight into this ‘cool’ matter at the event
"The Amazing Quantum World of Ultra Cold Matter", held at this year’s
ESOF (Euroscience Open Forum) in Barcelona. It was co-organised by the
European Science Foundation (ESF) and The Institute of Photonic
Sciences (ICFO) within the collaborative research programme "Cold
Quantum Matter" (EuroQUAM).

Maciej Lewenstein leads the
quantum optics theory group at ICFO and is a Humboldt Research Prize
Awardee. Introducing the basics of quantum mechanics, he explained
without mathematics why laser light cools atoms and told the audience
about recent developments in atomic, molecular and optical physics and
quantum optics, toward reaching temperatures close to absolute zero. "I
expect major developments in fields like quantum information", said
Lewenstein. He argued that while in classical physics absolute zero is
in certain sense "boring", in the quantum world new, fascinating states
of matter such as Bose-Einstein condensates arise at ultralow
temperatures. Moreover, he elaborated on the tremendous advances in
physics that have made such experiments possible, and which led to
Nobel prizes in physics in 1997 and 2001. "Concerning Nobel Prizes in
this area, it’s only a question of who’s next" predicted Lewenstein.

Christophe
Salomon is Head of the cold Fermi gas group at Ecole Normale
Supérieure, France and Principal Investigator for the ACES/PHARAO Space
Clock Mission. He has received the "Three Physicists" prize (FR), the
Mergier-Bourdeix Grand Prize of the French Academy of Sciences, the
European Time and Frequency Prize, and the Philip-Morris Prize.

In
his talk "Precision Time with Cold Atoms" he described an important
application of cold atoms, the realization of ultra precise clocks.
Using atomic fountains and microwave radiation, the SI unit of time,
the second, is realised with an error of less than one second over 100
million years. Clocks operating in the optical domain show even better
performances and cycles of light can now be easily counted with a
femtosecond laser. "In a few years clocks will be able to monitor local
changes of the Earth gravitational potential by using relativity, which
might help us forecast tsunamis, earthquakes, or global climate
warming", said Salomon.

The third speaker, Christopher Foot,
Professor of Physics at Oxford University, elucidated "The
extraordinary behaviour of quantum systems". Small particles such as
atoms and electrons behave in strange ways that often seem very weird
when compared to our everyday experience of large ‘ordinary’ objects
such as a tennis ball or football. For these very small objects the
effects of quantum mechanics are manifested in striking ways, which
Foot outlined.

A single quantum object can exist in two
places at once – "It is in a state of indecision" said Foot.
Additionally, there is a second property of quantum systems of two or
more particles that is truly difficult to understand, known as
entanglement. Indeed Einstein pointed out that this so-called "spooky
action at a distance" is so bizarre that he thought there must be
something wrong. Experiments have shown, however, that the quantum
world really behaves in this peculiar way. "By understanding it we can
do new things such as build quantum computers that, in the future,
could store and process far more information than ‘ordinary computers’
and may outperform them in certain applications, e.g. cracking the
encryption commonly used to transmit information electronically"
explained Foot.

With current technology, quantum systems of
many atoms at temperatures less than one millionth of a degree above
absolute zero can be made. These systems can be controlled in such a
way that they act like small quantum calculating machines, or ‘quantum
simulators’, with which the quantum properties of a wide range of other
interesting physical systems can be studied. Foot also gave an example
of this type of experiment currently carried out in the EuroQUAM
Programme, where laser beams are used to form ‘optical lattices’ that
resemble crystals.

Spanish Anchorman and former Minister of
European Relations in the Spanish Government Eduardo Punset moderated
the event, and Jürgen Eschner, an experimentalist and group leader from
ICFO, was the main organizer of this activity of EuroQUAM. "I think our
biggest challenge in the coming years is to bring together knowledge
and entertainment, and the speakers captivated the public here in
Barcelona" said Punset. ESOF marked a unique opportunity for EuroQUAM
to go public with its research and make cold quantum matter more
graspable. "We have clearly conveyed the fascination that the EuroQUAM
scientists have for the exciting fundamental phenomena and
technological opportunities of ultra-cold matter" concluded Eschner.

European Science Foundation

For further information on EuroQUAM, please go to www.esf.org/euroquam.   

For further information on EUROCORES, please go to www.esf.org/eurocores.

For further information on ICFO, please go to www.icfo.es.

Alice would like to transmit a stream of quantum information to Bob. She shares entanglement in the form of ebits before quantum communication begins. Red qubits belong to Alice and…               Click here for more information.

The Viterbi Algorithm, the elegant
41-year-old logical tool for rapidly eliminating dead end possibilities
in data transmission, has a new application to go alongside its
ubiquitous daily use in cell phone communications, bioinformatics,
speech recognition and many other areas of information technology.

In
a recent set of papers two investigators from the University of
Southern California school that bears the name of the algorithm’s
inventor say it can play a key role in quantum communication.

Mark
Wilde, a graduate student in the USC Viterbi School of Engineering,
collaborated with his faculty advisor Todd Brun on the work. The
research is also his thesis, for which he will receive a PhD from the
School’s Ming Hsieh Department of Electrical Engineering in August.

Brun,
an associate professor in the Hsieh Department, is also deputy director
of the USC Center for Quantum Information Science & Technology.

The
quantum communication applications Wilde and Brun explored are for an
environment in which a sender "Alice" (the traditional sender name) is
trying to send a quantum message to a receiver named (again by
tradition) "Bob" using a stream of pairs of "entangled" photons.

"Such
[entangled] photons," in the words of the recent New Scientist story,
"obey the strange principles of quantum physics, whereby disturbing the
state of one will instantly disturb the other, no matter how much
distance there is in between them."

Use of such a system has
been proposed for a variety of uses, including space based
communication, and progress is being made on the physical devices that
might create entanged photons for messages. But noise is created in the
transmission of quantum data, an issue the USC work addresses using the
time-hallowed Viterbi algorithm.

In the system considered by
Wilde and Brun, Alice encodes each quantum bit of the message with the
help of an ebit, an entangled qubit. She sends her part of the encoded
quantum message over a noisy quantum communication channel, a process
that can introduce errors.

From his side, Bob receives what
Alice sent and combines her transmitted qubits with his half of the
ebits. He measures all of the qubits, processes the results of the
measurements, performs recovery operations, and finally decodes them,
receiving the message qubits Alice sent. At the conclusion of the
process Bob will have the transmitted quantum information error-free.

The
above description is a condensed and simplified paraphrase of what is
in fact a much more complex process, a ballet in which Alice and Bob
can exploit ancilla or helper qubits, gauge or noisy qubits, and ebits
to transmit both quantum and classical information.

But the
bottom line question coming out remains, how does Bob know that the
dancers were following the music, that the message he now has was
transmitted correctly?

The fact that the noisy quantum
communication channel can be modeled as a sequential process of steps,
each step of which changes the state of the system, offers an opening.
The Viterbi algorithm is, precisely, a way of analyzing the products of
such progressions, called "Markov processes."

In Wilde and
Brun’s analysis, Bob watches the step coming out of his measurement
process, testing them against statistical probabilities, using standard
Viterbi tools.

Cell phones use similar programming to correct for errors in the transmission of digital voice data.

The
result: Bob can reliably spot errors, and knows which message qubits
are bogus before he opens the message – crucial, because opening it
destroys it; and if it is garbled, he has nothing.

With thanks to the University of Southern California

First of all, note that mass and energy are equivalent. So, the
total mass of the Universe need not be conserved even though the total
energy (taking into account the energy that is equivalent of the mass
in the Universe) is
conserved. Mass and energy are related by the famous equation E=mc².
Hence if there is enough energy, photons can create matter-antimatter
pairs. This is called pair production and is responsible for the mass
in the Universe.

As to where everything came from, there is no conclusive
opinion. One idea was that the Universe was created from vacuum. This
is because according to quantum theory, the apparently quiescent vacuum
is not really empty at
all. For example, it is possible for an electron and a positron (a
matter antimatter pair) to materialize from the vacuum, exist for a
brief flash of time and then disappear into nothingness. Such vacuum
fluctuations cannot be observed directly as they typically last for
only about 10^-21 seconds and the separation between the electron and positron is typically no longer than 10^-10 cm. However, through indirect measurements,
physicists are convinced that these fluctuations are real.

Hence, any object in principle might materialize briefly in the vacuum.
The probability for an object to materialize decreases dramatically
with the mass and complexity of the object. In 1973, Edward Tyron
proposed that the Universe is a result of a vacuum fluctuation. The
main difficulty of
this proposal is that the probability that a 13.7 billion year old
Universe could arise from this mechanism is extremely small. In
addition, physicists would question Tyron’s starting point: if the
Universe was born from empty space, then where did the empty space come
from? (Note that
from the point of view of general relativity, empty space is
unambiguously something, since space is not a passive background, but
instead a flexible medium that can bend, twist and flex.)

In 1982, Alexander Vilenkin proposed an extension of Tyron’s
idea and suggested that the Universe was created by quantum processes
starting from "literally nothing", meaning not only the absence of
matter, but the absence of space and time as well. Vilenkin took the
idea of quantum tunneling and proposed that the Universe started in the
totally empty geometry and then made a quantum tunneling transition to
a non-empty state (subatomic in size), which through inflation (the
Universe expands exponentially fast for a brief period of time which
causes its size to increase dramatically) came to its current size.

Another idea is from Stephen Hawking and James Hartle. Hawking
proposed a description of the Universe in its entirety, viewed as a
self-contained entity, with no reference to anything that might have
come before it. The
description is timeless, in the sense that one set of equations
delineates the Universe for all time. As one looks to earlier and
earlier times, one finds that the model Universe is not eternal, but
there is no creation
event either. Instead, at times of the order of 10^-43
seconds, the approximation of a classical description of space and time
breaks down completely, with the whole picture dissolving into quantum
ambiguity. In Hawking’s words, the Universe "would neither be created
nor destroyed. It would just BE."

So, the origin of mass in the Universe and the Universe itself
is quite speculative at this point. If you are interested, you can read
Alan Guth’s book "The Inflationary Universe", page 271-276. You can
also read Hawking’s "A brief history of time: From the Big Bang to
black holes" page 136.

Ask an Astronomer is run by volunteers
in the Astronomy Department
at Cornell University.

During World War II, American pilots were given hollow metal spheres
to be used when their planes went down over water. Metal, as you
probably know, tends to be quite heavy and quite useless as a flotation
device. So why were these pilots given chunks of metal? Well, they were
told that if they dropped the sphere into the ocean, their current
position could be worked out by allies in the region, and they would be
rescued. However, as foreign intelligence was soon to find out, the
spheres were just that – hollow metal spheres – no electronics, no
radio equipment, no imbued magical properties. So was the military just
playing with it’s pilots, or was there actually something to these
spheres?

Well, some of the details are still kinda top secret, but with a
little physics and an active imagination, it’s possible to work out how
they were used. Arrgh! Scary! I just said the P word. Don’t worry, I’ll
try to summarize things without delving to deep into the physics.

Simple Facts: The Ocean

• The deeper you go, the colder it gets
• The deeper you go, the higher the pressure

Simple Facts: Soundwaves

• Sound travels in waves

• These waves bend towards where the sound travels _slower_
• Sound travels faster in warm temperatures than cold temperatures

Combining the facts:

So, if a sound originates in the sweet spot, between
these two areas of bending, it gets trapped, and ends up travelling
great distances. This is called the sound channel:

Note, if a sound originates outside of this channel, it
gets deflected somewhat, but doesn’t bend back enough to get trapped.
Note also, that the lines here show the path of the wave, not the wave
itself. View each line as a zoomed out version of the wave pictures
above.

Keep your eye on the sphere:

So, the spheres that the pilots were dropping into the ocean were of
a specific thickness that would be crushed by the ocean pressure at
about 1km deep. This would cause a “ping” that could be detected
by underwater microphones thousands of miles away. By triangulating the
sound (kinda like how GPS works) the Navy was able to work out where
the sphere was dropped and go rescue the pilot!

Implications – LOFAR:

I don’t believe it – I am about to recommend a Tom Clancey novel, The Hunt for the Red October. Tom goes into details as to how the US Navy took this technology and
used it to detect submarines that entered the sound channel. I’d
totally recommend buying it here for those of you who have enjoyed
reading this posting.

Implications – Nature:

It turns out that nature beat us to the punch. Whales have been using
the sound channel for years to communicate with each other over long
distance via Whale Song!

Source

Quarkonia are types of mesons containing two quarks: one quark and its
anti-quark (they are therefore "colourless"). They belong to one of two
families: "bottomonium" or "charmonium". As the names suggest,
bottomonium contains a bottom quark and anti-bottom quark; charmonium
contains a charm quark and anti-charm quark. Groups of three quarks
(interacting via the strong force) are baryons (i.e. protons and neutrons) whereas groups of two quarks are mesons.
Mesons are all thought to be made from a quark-antiquark pair and are
therefore of huge importance when studying why there is more matter
than anti-matter in the Universe.

This is where the BaBar detector at the Stanford Linear Accelerator Center (SLAC), CA, comes in. The BaBar international collaboration investigates the
behaviour of particles and anti-particles during the production of the
bottomonium meson (bottom-antibottom quark pairs) in the aim of
explaining why there is an absence of anti-particles in everyday life.

For each particle of matter there exists an
equivalent particle with opposite quantum characteristics, called an
anti-particle. Particle and anti-particle pairs can be created by large
accumulations of energy and, conversely, when a particle meets an
anti-particle they annihilate with intense blasts of energy. At the
time of the big-bang, the large accumulation of energy must have
created an equal amount of particles and anti-particles. But in
everyday life we do not encounter anti-particles. The question,
therefore, is "What has happened to the anti-particles?" – From the BaBar/SLAC collaboration pages.

All matter has a "ground state", or the lowest energy the system is
trying to attain. As particles for instance try to reach this ground
state, they lose energy, often in the form of electromagnetic
radiation. Once reached, the ground state determines the baseline at
which measurements can be made for higher energy states of those
particles. And this is what the BaBar team has done, they have been
able to isolate the lowest possible energy state for the bottomonium
particle (which is far from easy). So what have they named the ground
state of bottomonium? Quite simply: ηb, pronounced "eta-sub-b".

The bottomonium particle was generated during a collision between an
electron and positron. The energy generated by this collision created a
bottom quark and an anti-bottom quark bound together. At this point,
the bottomonium particle was of too high an energy, but it very quickly
decayed, emitting a gamma ray leaving the ηb behind. However, ηb’s are
highly unstable and will quickly decay into other particles, plus they
are very rare and difficult to detect. This particular decay event only
occurs once in every two or three thousand higher energy bottomonium
decays, so many collisions had to be measured and a huge amount of data
had to be gathered by the BaBar detector before a precise measurement
of the ηb ground state could be gained.

"This very significant observation was made possible
by the tremendous luminosity of the PEP-II accelerator and the great
precision of the BaBar detector, which was so well calibrated over the
BaBar experiment’s 8-plus years of operation. These results were highly
sought after for over 30 years and will have an important impact on our
understanding of the strong interactions." – Hassan Jawahery, BaBar Spokesperson, University of Maryland.

If you want to find out more, you can check out the BaBar team’s publication (with the longest list of co-authors I’ve ever seen!) or the SLAC press release.

Source

If a silver thread is heated to around 900 degrees Celsius, it will generate vapour made up of
silver atoms. The floating atoms stick to each other in groups. Small
lumps of silver comprising for example 9, 13 and 55 atoms appear to be
energetically stable and are therefore present in the silver mist more
frequently that one might assume. Prof. Andreas Schmidt-Ott and Dr.
Christian Peineke of TU Delft managed to collect these super atoms and
make them suitable for more detailed chemical experiments.

The underlying mechanism governing this stability in super atoms was described in Science
by scientists from Virginia Commonwealth University in 2005. They had
discovered metal super atoms, but from aluminium. Their aluminium
clusters of 13, 23 and 37 atoms reacted in the same way as individual
atoms because they comprised electrons that revolved around the atom
cluster as a whole. These so-called outer layers were strikingly
similar to the outer layers of elements from the periodic table.

The super atoms gave the periodic table a third dimension as it
were, according to Schmidt-Ott: ‘The chemical properties of the super
atoms that have been identified up until now are very similar to those
of elements in the periodic table, because their outer layers are much
the same. However, we may yet discover super atoms with a different
outer layer, giving us another set of completely new properties.’

Schmidt-Ott hopes to find atom clusters with new unique magnetic, optical or electrical properties,
which would also be stable enough to create crystals or other solid
forms. Potential applications include catalysts in fuel and
extra-conductive crystals.

So although super atoms are nothing new, thanks to TU Delft the
particles can now be collected in a very pure form and selected
according to size, thereby making them suitable for chemical
experiments.

Full article can be read in the new edition of TU Delft magazine Delft Outlook. See http://www.delftoutlook.tudelft.nl

Dr Usherwood believes the reason that
flying creatures don’t look like man made machines is all to do with
the need to flap. "Animals’ wings, unlike propellers, have to keep
stopping and starting in order produce lift (animals have forgotten to
invent propellers, just as they forgot wheels)," he explains. "Think of
vigorous waving, or perhaps exuberant rattling of a cocktail shaker -
this takes a fair amount of power to overcome inertia. So, the idea is
that both wing shape and how wings are used can be understood better if
the effort of flapping is remembered, which explains why vultures don’t
look like gliders, and most winged creatures, from insects to pigeons,
fly so inefficiently."

His research has centred on creatures
as diverse as dragonflies and quails. Currently he is investigating the
compromise winged creatures face between meeting aerodynamic
requirements and overcoming inertia in order to generate lift, by
loading wings of racing pigeons with lead fishing weights. He believes
that lessons from all of these studies lead to the same conclusion. "My
work should act as a reminder to be cautious in copying nature. There
is lots of interest in making MAVs/UAVs (micro/unmanned air vehicles)
that flap, which may present all sorts of advantages in terms of
maneuverability, speed and so on. However, there is a tendancy to
presume that biology is efficient, and I would say that, even at very
small sizes, if you want to hover efficiently, be a helicopter not a
flapper…"

For more information please visit Society for Experimental Biology

Found this on Hollowmarked’s Blog

For a video of Brian Cox at the TED conference check out an earlier post I made

Brian Cox on CERN’s supercollider

TO: Is there any real disagreement? Are there camps that have developed?

BC: Oh absolutely; there’s a huge disagreement
because this is–it’s truly a leap into the unknown. I mean you hear
that a lot about scientific experiments but this one really is a big
jump. The most powerful accelerator at the moment is in Chicago
actually; the Tevatronat Fermilab where I’ve worked. I worked there before I moved onto the LHC. And the
LHC is an order of magnitude pretty much–increase in energy and it’s a
huge increase in the number of proton/proton collisions we can have
every second, so it–in a sense I was going to say all bets are off.
It’s not quite true; I mean we know some things that we’re going to
discover so we will discover the origin of mass in the universe, the
mechanism that generates the mass for the fundamental particles.

TO: And that would be the Higgs Boson?

BC: Well yeah it would be. I mean the correct thing
to say is whatever does that job we should see. I mean I would say
actually we will see; as long as the machine functions properly we’ll
see it. It could be the Higgs; yes–in a sense the most likely and that
it’s a theory that works and–but it could be something else and you
will find people who don’t–certainly don’t believe in the so-called
standard model Higgs. There–there are many different Higgs theories;
there’s the–or Higgs manifestations of the Higgs mechanism. One of
the–the standard model of the Higgs at the [simplest] you find one
Higgs particle covers standard model Higgs, but there are so-called
sleeper symmetric theories that many people think are actually possibly
more likely. And in some of those theories, the [simplest] you get five
Higgs particles. You know so–so even the Higgs–you can have different
camps as to how many Higgs particles you’ll find. It’s fascinating
times to be a particle physicist.

TO: So the existence of the Higgs was suggested in the early ’90s in Chicago; is that true?

BC: No; it was the–we’ve got no direct
experimental evidence for the Higgs particle. We’ve got–we’ve got
indirect evidence in that the standard model of which it starts, which
our best theory of particle physics at the moment–works and as far
as–and you can–we tested it to immense precision in Chicago at
Tevatron and experiments at CERN and at SLAC for that matter in San Francisco and elsewhere. And it always–it works beautifully well and the Higgs is a part of that. So you can claim it
as indirect evidence but you can evade that indirect evidence actually
very easily in the theories. So the correct thing to say is it might
not exist; it might be something else that we haven’t thought of yet.

TO: It’s called the Large Hadron Collider but I’ve heard you say protons.

BC: Yeah.

TO: Was the reasoning behind calling it the Large Hadron Collider is it going to be colliding other things besides protons?

BC: Well you can actually yes; it can collide nuclei so there is a program at the LHC to collide gold nuclei which is what RHIC does–the Relative Heavy Iron Collider–at
Brookhaven in New York. And so it can–it can collide different things.
The proton program is kind of the you know–the lead program in a sense
because that’s how you get the most amount of energy to the smallest
amount of space, so you can try to look at things like Higgs particles.
But there’s a whole program–clan within a detector called Alice which
is dedicated to heavy iron collisions, the nucleus collisions and they
look at these things called quark gluon plasmas, which that’s the way
the universe was believed to be let’s say a millionth of a second after
it began–it’s a big soup of quarks and gluons. So it can bang together
other things, but–yeah; maybe it’s just–I don’t know why you’d call
it–you could have called it the Large Collider I suppose. I don’t know
why it’s called the LHC; I’d have to ask–Lyn Evans is one of the LHC
Project Leaders. It’s a good question; I’m going to ask him that.

TO: So it’s not a large particle per se; it’s just a "large Collider"? It could be called the "Hadron Collider"?

BC: Yeah, yeah; no large just means big
27-kilometer in circumference ring, so [Laughs] yeah. I mean–although
it’s got to be said actually that protons are pretty big things
compared to the things we’re looking for, the elementary particles of
matter.

Some questions excluded

TO: In the circle and the protons travel in some sort of perfect vacuum? I mean how do they–

BC: Yes; there are actually two pipes for most of
the LHC, so two beam pipes and they’re about you know
what–10-centimeters maybe across you know–they’re not very big pipes,
so one going one way and one going the other way and those pipes are in
a–in what we call a cryostat so which is where the magnets are as well
and that’s I’m told one yard across–. Now that’s not me being quaint
in English. It’s the only imperial measurement in the LHC and it’s
there because that’s the diameter of a standard oil pipe. This is what
I’m told, so it’s cheaper to make things one-yard across. So basically
you’ve got a big pipe–one yard across with all the magnets and the
beam pipes embedded in it and that’s the thing that’s down at the–at
minus 271-degrees. And then as you say the beams are in beam pipes and
those bean pipes emerge into one pipe at the interaction point so at
the places where you cross the beams through each of the–so you get
the collision and that happens inside the four detectors of the LHC.

TO: There are four main test points on the circle?

BC: Yeah; basically–that’s right.

TO: And these are–what have these machines
like–if you look at something called the Atlas or the CMS, these are
at each of the points and that’s what you work on?

BC: Yes; so Atlas is a–you think of a digital
camera. It really is except that it’s 40-meters long and 20-meters
high; it’s a big cylinder. It’s in a cavern 100-meters below the
ground. It’s bigger than the nave of Notre Dame Cathedral in Paris.
So it’s an immense structure but its job is to sit around the point
where you pass the beams through each of them so you collide the
protons together and it’s in those collisions that you–one way of
thinking about it is recreating the conditions that were present less
than a billionth of a second after the universe began–for a fraction
of a second and it’s in those conditions that you hope to reveal the
earth–I suppose the underlying simplicity of the universe.

TO: Two protons, two positively charged particles
each made up of three quarks a piece–what do you get when you bang
those together?

BC: Well what you do is you get a big mess is the
answer. [Laughs] And what happens I mean protons are actually full of
stuff. The three quarks is a simple view; there’s other things called
gluons in there. There are more quarks that are not in there in a sense
so it’s a big bag of particles and what you actually do is you collide
two of the constituents together so let’s say two gluons bump into each
other. The rest of the protons fly out in the direction in which they
came as a big cloud of debris really. So typically you’ll bang two
gluons together and it’s that–that you’re interested in. Those two
gluons could produce a Higgs particle let’s say and then the Higgs
particle will decay into other particles and you’ll collect that debris
as well. So you’re interested–the protons are really energy
deliverers. All you’re doing is trying to get energy into this small
space and out of that energy you would hope to make new particles that
you’ve never seen before.

For more of the interview please check the whole thing over at Oreilly