legacy jQuery UI 1.7.3 accordion

When using jquery UI 1.7.3, it is required to include the header argument.  The documentation at http://jqueryui.com/demos/accordion/ did not state that explicitly, and could cause severe head-scratching and testing of imaginary bugs.

So the code should actually look like

$("#accordion").accordion({ header: "h3" });

the elusive Higgs boson

All theorized particles in the Standard Model of Particle Physics has been found except the Higgs boson. A confirmation of the existence of this particle will complete the theoretical description of over half a century of experimental and theoretical particle physics work. Yesterday, the combined data from the ATLAS (4.9 fb-1) and CMS experiments were shown in a public seminar from CERN hinting that the Higgs exists with a mass of about 126GeV(as a comparison, the mass of the proton is 0.938GeV).

Invariant mass distribution for the inclusive data sample, overlaid with the sum of the background-only fits in different categories described in Sections 3 and 4 in the ATLAS paper and the signal expectation for a mass hypothesis of 120 GeV corresponding to the SM cross section. The figure below displays the residual of the data with respect to the background-only fit sum. Source: ATLAS Collaboration

 As shown in the figure above, the dotted lines show how the Higgs would modify the Standard Model background.  It is a very minor modification so it requires high sensitivity of the detector.

The observed and expected 95% confidence level limits, normalised to the SM Higgs boson cross sections, as a function of the hypothesized Higgs boson mass. Source: ATLAS Collaboration.

We only see a 3.6σ(ATLAS) and 2.6σ(CMS) above the expected SM background for the Higgs mass of 126GeV in the figure above.  A 5σ significance is required to claim a discovery.

(to answer Mr. Hawkin's question) Do I want the Higgs to exist? Well, its kind of nice to have a theory being proven correct by experiment especially it involved the hard work of many generations of physicists.  Having the Higgs to exist at the low mass region of 115-150GeV would also be nice.  There will be other problems that physicists could work on and more work for me to do, supersymmetry maybe?

On the other hand, no Higgs means a totally different theory to explain where mass comes from.  Although there are already many theories like Technicolor or Higgless SM models, we will always have more work to do.

Autumn is here

Golden and red leaves decorate the once boring green tree.

London

In Trafalgar square

London.  I was there at the end of Spring 2011 visiting my brother who lives in the suburbs.  A big and lively city with people from all over the world calling it home.  I flew in from Copenhagen to Gatwick reaching at late night.

It was on a Saturday and a perfect sunny day as I remember it.  My mom and I took the train and then the London underground to explore London.  It was also the day after the Royal Wedding of Prince William and Miss Catherine Middleton.

We didn't have a plan beyond just deciding to walk along the Thames river.  All the sights are near the riverside, like the Big Ben, London eye, Shakespeares Globe theater and of course the London bridge.  I think we also went to check out Harrods, and the British Museum of Natural history.  I think the museum rocks...ha ha.  Too bad my mom thinks otherwise.

London Bridge station is not near the London Tower bridge!

Big Ben

Shakespeare's Globe Theatre

The London Tower bridge

At the Museum of Natural history.  My mom
got really bored here.

I don't remember where this is, a random street
in London or Windsor?

Trying to understand it all: The Standard Model Part 1

Source: PBS NOVA, Fermilab, PDG

The Standard Model of Particle Physics is the best model we have so far that describes matter and forces.  It took the combined effort of physicists spanning over more than half of the past century to come up with a theory that ties seemingly different things together.  In the figure on the left, there seemed to be a random combination of greek letters and some physics jargon about fermions and bosons.  If you have done some particle physics, you will disagree with the previous statement.

Anyway, you may also have realized that there are three 'kinds' of 'stuff' represented by the different colours: purple, green and red.  All the matter we can see, feel and detect so far (observable) are made from the 'elements' in the diagram.  The ones in the purple box, physicists call them quarks, green ones leptons and red ones exchange particles.  For example the proton, which makes up part of an atom's nucleus is made from two u-quarks and one d-quark.  The neutron, is made up of one up-quark and two down-quarks instead.  Then we also have electrons that usually orbit around the nucleus of the atom.  Electrons belong to the lepton (green) group.

Now, we have only talked about baryons (subatomic particles that consists of three quarks or antiquarks).  In 1935, Hideki Yukawa theorized the existence of the mesons as exchange particles for the strong nuclear force.  This idea was proven to be not true as the real exchange (or carrier) particle for the strong nuclear force is the gluon.  The first mesons (made from only two quarks or antiquarks), the pions (made from an u-quark and d-antiquark) was found in 1947 by Cecil Powell, César Lattes, Giuseppe Occhialini et.al. from cosmic rays.  Subsequent experiments detected charged pions and the neutral pion.

The strong nuclear force is mediated by the gluon between quarks and antiquarks in the proton, neutron for example.  They bind the quarks together so hard we never get to see any 'naked' quarks in nature.  Everytime you pull the quarks apart and when you think you put in enough energy to split them, they convert that energy into a quark-antiquark pair and you get two mesons or baryons.

Pulling on the quark pairs in mesons create even more
mesons, resulting in a mess (jet) of particles.
Source: Wikipedia

The accelerating universe

Cepheid stars, maybe not the ones
that Hubble used.  Courtesy of Cepheid stars
from galaxy, Zwicky 18
(Hubble telescope image)

This year's Nobel prize for physics (2011) went to Saul Perlmutter, Brian P. Schmidt, Adam G. Riess for the discovery of the accelerating expansion of the Universe through observations of distant supernovae.

The story started with Albert Einstein and Edwin Hubble.  Einstein has just published his Theory of General Relativity (1916).  What follows is Einstein's self-proclaimed 'biggest blunder'.  He believed that the universe was static(fixed size) so he added a cosmological constant, Λ into his field equation of the universe since his original equation showed that the universe was expanding.  There was no observational evidence for expansion at that time.

... and Hubble finished measuring the speed of Cepheid stars moving away from our galaxy, the Milky Way a few years later.  This means that our universe is slowing expanding.  This means that there was no need of a Λ term.

Einstein's field equation

Therefore, Einstein's blunder.  He could have predicted the expansion of the universe from his Theory of General Relativity.

Hubble changed the way we look at the universe.  He found other galaxies besides our own (1922).  More importantly, from his observations, he found out that the universe was expanding at a constant rate (1929).  There was a beginning to the universe which we now call the Big Bang.  To the right is Hubble's plots of the the speed of stars moving away from us.  You can see that the further the star from us, the faster it moves away from us.

Fit of redshift velocities to Hubble's law;
patterned after William C. Keel (2007).
The Road to Galaxy Formation. Berlin: Springer
published in association with Praxis Pub.,
Chichester, UK.

Later in the 1990s, two research groups (High-z Supernova and Supernova Cosmology) looking at supernovae (Type 1a) found out that the universe not only expanded at a constant rate, but actually accelerated.

It was generally assumed that the expansion rate would slow over time as gravity pulled the universe back together. The two groups above that used supernovae to study more were astonished when they added their new data points to the Hubble diagram.  The universe not only did not slow down expanding but actually expanded even faster.  In the plot below, if the universe were expanding at a constant rate, all the points in the lower plot would lie in a straight horizontal line at zero. Instead, the supernovae with higher velocities lie above the line.

 This was the first evidence that the universe is expanding at an
accelerated rate, driven by something we choose to call "dark energy".
Courtesy of the High-Z Supernova Search Team

What does this mean for us?  One direct consequence would be that the universe would end in a 'Big Freeze' if this were true.  All the stars will burn out, black holes evaporate and the universe will be cold and dark in the end.  The universe dies a heat death.

From the past: Phuket

The sun, the sea, the umbrellas.

Phuket.  Who isn't familiar with this beautiful island off the west coast of Thailand?  Plenty of tourist from all over the world travel to this island to holiday.  Many of them from the cold northern European countries but also many from the neighbouring south-east asian nations.  I have been informed by many of my Swedish friends that those with lots of money go holidaying in Thailand and those with less go to Greece.  I definitely agree, when the winters in Sweden or Scandinavia in general are cold and depressing.  You get only about 6 hours of daylight or less in the middle of winter.

Sure, for short term visitors like me, winter sounds like fun.  The snow, the white christmas experience.  It is a hassle to need to always check the weather or outdoor temperature when you are going out so that you do not under-dress.  Winter needs some getting used to.  Ok, anyway, Phuket was devastated in Dec 2006 when it got struck by a powerful tsunami originating from the Indian ocean.  Ever since then, they have reconstructed everything and when I was there, you would not even know that the area was totally destroyed by the massive tidal waves.

Welcome to the red light district.

Phuket seems lovely.  Nice beaches, good food, friendly locals.  Rows of shophouse line the beaches, with the more expensive shops closer to the beach and the ones that the local frequent, far inland.

Rock and roll.

Selling smoke cuttle fish, I think.

More pictures of the beach.

Before

After

Suprisingly you get Dimsum here.

Proof I was there. Haha

Thai elephants :)

What's next: After Tevatron

On October 13, 1985 at Fermilab, the Tevatron produced protons and antiprotons collisions inside the CDF detector for the very first time. It was a magical day for the few dozen people in the accelerator and CDF control rooms. Since that day, literally billions of matter-antimatter collisions took place inside CDF and then inside CDF and DZero. What was once novel is now routine – and routine at an unprecedented scale. The intensity of the beams gradually multiplied, thanks to the relentless efforts of the Tevatron accelerator physicists.

Friday at 2 p.m., after nearly 26 years of operation, a switch will be turned, ending the career of one of the most remarkably successful colliders ever in particle physics. The Tevatron collider established a brand identity for Fermilab and changed the physics landscape forever... 

- Rob Roser and Giovanni Punzi, Fermilab

Tevatron.  Courtesy: Fermilab

The Tevatron has it share of important particle physics discoveries.  It has been said that the accelerator has done its job well.  It accomplished what it was built for.  However, physicists were a bit disappointed since they could not get a whiff of new physics from the Tevatron, or at least find the Higgs boson.

The Tevatron hosted two detectors, CDF and D0.  Both the CDF and D0 detector takes snapshots of the particles that emerge when protons and antiprotons collide.  This collision produces a gezillion amount of particles that physicists will have to sieve through and find the ones that we have never seen before.  The Tevatron discovered

• the top quark and determined its mass to a high precision
• two distinct production mechanisms for the top quark: pair and single production
• five B baryons (2 cascade, 1 omega and 2 sigma _b)
• Bc meson
• Y(4140), a new quark structure
• Bs oscillation

source: Fermilab

So now, it is up to the LHC@Cern to find the Higgs boson, or something to replace it.  For the near future, the data generated by the Tevatron will be analyzed by physicists.  A new accelerator research center will also be built at the CDF site.  For those interested to watch the closing ceremony, here is the link.  The show starts at 2pm GMT-5.

Note:  Top quarks are very massive, as heavy as a Gold atom. It requires large amounts of energy are needed to create one and the only way to achieve such high energies is through high energy collisions. These occur naturally in the Earth's upper atmosphere as cosmic rays collide with particles in the air, or can be created in a particle accelerator. As of 2011, the only operational accelerators that generate beams of sufficient energy to produce top quarks are the Tevatron at Fermilab, in which protons and antiprotons are collided and the Large Hadron Collider at CERN.

What's smaller than a proton?

A proton, made of two up quarks and a
down quark

Since Rutherford's scattering experiment with gold and alpha particles (that came from the decay of radium) that proved the atomic nucleus had minute size and a positive charge, we have came a long way in understanding the atom and fundamental particles that make up our universe and ourselves.  We now know with reasonable doubt that the atom is made up tiny point-like electrons orbiting a nucleus of protons and neutrons (except the hydrogen atom of course).

One classification of one type of
baryons (particles made of three quarks).
Mesons on the other hand are made
of one quark and one anti-quark.
Courtesy of Fermilab

Entering the second half of the 20th century, particle physicists discovered a zoo of 'elementary' particles, pions, kaons, J/ψ, and many others.  They thought nature would not be so complicated and they sought out a theory to explain the existence of these particles.  Similar to the work done on the periodic table of elements, using the proton number to order the elements, Murray Gell-Mann and Yuval Ne'eman independently suggested a theory to explain that all the 'elementary' particles are not so elementary after all.  The problem with theory is that although it was able to explain the particle zoo, quarks were never seen before.  They were never created and observed in the laboratory.

SLAC, USA

Ok, so if we can't create and see them, how are we so sure they exist?  Particle physicists have shot protons with high energy electron beams to show that they actually are composite, e.g. made up of quarks.  At the Stanford Linear Accelerator (SLAC), they repeated the earlier Rutherford experiment but the target was now a proton and the beam an electron.  The results showed that the electron moved in a way that suggested that the proton was not a point particle.  At even higher electron energies, they see the electron move (scatter at an angle) even more.  This proved, like how Rutherford proved that there was localized structured in the atom, that there were substructure in the proton.  We now call them quarks (Feynman called them partons).

Other experiments like HERA in Hamburg, Germany also studied the structure of the proton.  In addition to the two up-quark and one down-quark we say made up the proton, there is a sea of quarks, or rather valence quarks (analogous to the valence electrons orbiting the atom).  

Our current picture of the proton.  It
consists of quarks, antiquarks and
gluons.

These pairs of quarks and anti-quarks exist only momentarily; formed from an energetic gluon, they will come back together and annihilate returning once again to a gluon.  They probed to the smallest visibility and saw up to 100 of these quark/anti-quark pairs at any instant.


I just used the word 'gluon' without explaining.  Basically it is something that gets passed around between quarks when they interact.  You do not see them directly too.  Strange how particle physics has evolved right?


I'm flying back to Sweden tonight.  Looks like I am going to miss the sun and the windless weather in Meyrin for the colder air of Lund.  Update:  Flight got redirected to Frankfurt before going to Copenhagen.  Looks like I get to see some of Germany today.

From the past: Kota Kinabalu, Sabah

Changi Airport, Singapore where we started from early in the morning.

This is a post about something I did way back in 2008, when I was still in Singapore.  Reaching the top of Mount Kinabalu has been on my to do list for a while back then and so when some friends asked me if I wanted to join them to conquer the mountain, I jumped at the chance to do so without any second thoughts.  These pictures have been in Facebook for years now but I did not like their policies about sharing and privacy so I moved them out from there.  Personally writing blogs do more justice to these pictures which otherwise would just gather 'cyber-dust' in a photo album in FB.  Enough about my bias personal opinions about FB and on with the fantastic trip I had a few years back.    For those we are not sure where this nice mountain is, here's a map of the region.

Tourism map of Sabah, Malaysia.  Source: sabahtravelguide

Mount Kinabalu is the fourth highest mountain in South-east Asia at 4095m above sea level.  For Malaysians accustomed to the rainforest, the mountain offers different types of vegetation due to its height and local climate.  Near the bottom of the mountain, you find normal rainforest and gradually up, the trees become shorter with bushes and flowers growing and slowly they change into short shrubs, mosses and lichens that grow on the rock near the summit.

We arrive via Airasia the well-known low-cost carrier from Malaysia, now flying almost all of Asia and some parts of Europe.  We spent the first day exploring the city, Kota Kinabalu, after putting down our luggage in the hostel, which is along Jalan Gaya.

The hostel we stayed in along Jalan Gaya, Kota Kinabalu.  As I remembered it, there were lots of rooms with some visitors from Europe.

There were many things on sale.  I remembered there was a 'kueh chap' stall below our hostel.  I'm not particularly a fan of intestines or pig organ soup but most of my travel friends did enjoy them.  I ate the toufu portions instead.

Pet animals for sale, a prize Persian cat here for RM1600.

The Sunday market in Jalan Gaya.

Some photos of Kota Kinabalu, the state capital of Sabah.

Street view of Kota Kinabalu.  Hot, dusty and smoky.  Typical Malaysian city.

Walking towards the fish market and boat harbour.  We are all appreciating the shade provided by this overhead pedestrian crossing.

There are also boats to visit the islands, Gaya, Sapi, Manukan, Sulug, Mamutik.  They are popular for snorkelers and scuba divers.  Perfect for a day trip to play in the nice beaches too.  You will see many families with kids there.  I got stung by a jellyfish in Pulau Manukan on the last day of our trip.  I still bear the mark of tentacles on my leg.

Boat terminal for tourists going to the islands off Kota Kinabalu.

Now I realized these photos are probably not in the right time order.  It does not matter too much anyway.  Just enjoy the pretty pictures of tropical Malaysia.

Inside a souvenir stall.  Picture of a friend looking for T-shirts?

Walking in the pathway between stalls.  You can see the rattan balls on the right.  We play sepak takraw with them.

More rattan products.  Happy.

Hm... I think they are junk food, er... snacks made from deep fried fish .

Yes, coconuts.  They are aplenty in Malaysia.  I think they cost like RM1 each.  Please do not drink too much.  You will get sick of it. Haha.

Coconut juice.  Refreshing on a hot day.

Fishing boats.

Almost sunset over the islands.

Its dinner time.  Here you see aquariums of sea creatures like fish and prawns ready to be chosen by us to be cooked in the many ways possible.

Coconut tree along the coast.  They grow like weeds here.

Mount Kinabalu

Some things never change.  A nice instant cup of coffee where you don't expect one.

A map of the Mesilau path we took to go up the mountain.  Takes approximately 8 hours from our starting point about 1000-2000m above sea level.  Climbers must be accompanied by guides.

View from Kundasang.

Fruit and vegetable market in Kundasang.

Due to its cooler climate, the farms located at this highland plateau surrounding Mount Kinabalu and the Crocker range are able to grow temperate climate vegetables like cabbages and strawberries.

I think this was a picture of us just reaching our chalets at Timpohon Mesilau gate (Thanks luyee!) where we are to stay a night before our journey up the mountain.  This stay was mandatory as required by Sutera Sanctuary Lodges.  Since privatization of the mountain park management, everything has become expensive.

Photo from the Mesilau trail.

A small pitcher plant.

Squirrel I see.

Laban rata.  The place to hang out ~800m away from the summit.  We slept a little there and had to wake up in the middle of the night about 1am to start our final ascent to the top.  This is so that we will be able to see the sunrise while on the peak.  This is the second mandatory stop and stay.

Our beds for six hours in Laban rata.

A bit more!

Sunrise.  Too cloudy to see the round sun.

Once day breaks, you see many trekkers who reached the summit.

Above the vegetation level, there is a rope where you can use as a guide to reach the top of the mountain. 

Its a long drop down there...

Pictures really not in order.  This is a sign showing that we have made it to the summit, Low's Peak.