The Fluid Dynamics Simplification

Apparently we breathe air between 8 and 14 times a minute. Despite this a physicist may tell you that air is negligible, insignificant, of no concern. The reason for this is physics sometimes needs to be simplified to work. One of the most common simplifications is to ignore air resistance altogether. At the point at which air becomes a concern it becomes its own subject: Aerodynamics, a smaller part of Fluid Dynamics. To fully appreciate the topic of Fluid Dynamics, I spoke to Jamie Nutter, a PhD student studying that very topic at Imperial College London.

An Interview with a Fluids Researcher

Me: "Why did you choose to study Fluid Dynamics?"

Jamie: "I’ve always been a fan of F1 and so aero always appealed to me in that way. But I think mainly it was Prof Vladimir Vladimirov (My masters supervisor) who sparked a real interesting in aero while I was doing my masters project. He was the one who first suggested the idea of doing a PhD and encouraged me to pursue one in Fluids."

* Of course Fluid Dynamics has more important applications that just racing. However, Sebastian Vettel would have definitely not won the F1 championship if his team were not considering a whole collection of Fluid Dynamics funk. The effect of air battering the Formula 1 really does affect its performance.*

Me: "Can you tell me a little bit about your research?"

J: "My research is in laminar flow control, funded in part by Airbus, essentially we are looking at the mechanism by which flow over an aerofoil becomes turbulent and attempting to understand and design controls to encourage a more laminar aerofoil. This is to reduce the drag caused by the aerofoil and lead to a reduction in fuel costs. "

** So Jamie looks into how turbulent (rough) flow is created and what mechanisms can encourage a more laminar (smooth) flow. Seeing is believing and below show a picture of turbulent and laminar flow of candle smoke. **

Laminar and turbulent candle smoke. When the smoke rises it starts off laminar, as it continues upwards it gets affected by the air, ultimately creating turbulent smoke. Image courtesy of a Google search.

Jamie continued to explain his research in finer, more technical detail:

J: "We do this by considering asymptotic approximations to the Navier-Stokes equations.
Specifically my work has been in two parts. Firstly I considered a wave like instability (called a Tollmein-Schliching wave) and looked at the effect of having a flow over an aerofoil with a porous section (almost like suction through a porous wall). Secondly I am now considering a streamwise vortical instability (called a Gortler vortex) and am looking at the effect of varying curvature, such as you have on the underside of a wing."

Aerofoil: a cross section of an object designed to alter flow. Image courtesy of another Google search.

Me: "Do you know of any good, free resources, perhaps that you used, on Fluid Dynamics?"

J: "There aren’t that many free resources that I know of. Being a member of Imperial allows me access to plenty of papers and journals, which is invaluable. But other than that there isn’t much. If we want, say, a cross-section of a particular wing we can get this off Airbus but that is only because we are funded by them."

Me: "What would you say to someone starting their journey to a career in Fluid Dynamics? Are there any particular pitfalls or rewards to watch out for?"

J: "I’d encourage anyone starting out in Fluids, it’s very enjoyable and a really applicable part of maths to the real world. There are plenty of opportunities for jobs. However if you’d like to follow the academic route it is very competitive, there aren’t that many post doc. positions and you have to be prepared to travel around a bit to find them.
The work it self should be interesting, there are lots of areas in Fluids to study. Our laminar flow control study is interesting but also Micro Fluids, Biological Fluids, and Environmental Fluids have some really interesting applications. You may need to be prepared to do a lot of coding, and researchers for some reason love FORTRAN, and writing up in LaTeX but if you don’t mind that too much the maths can be a real joy."

Me: "I want to study Fluids..."

A Reservoir of Resources 

So this is the section where I point you to the places that you can learn about Fluid Dynamics. Regardless of what factor of Fluid Dynamics floats your flapper, you will need to know the core components.

Level 1 (HyperPhysics)

I like to start light where I can, HyperPhysics is light, Level 1 and has a good section about fluids: Fluids at HyperPhysics.

Fluids at HyperPhysics.

Level 2 (Fitzpatrick)

After Level 1 it's a big jump, The Fitzpatrick Physics Files post landed a reet good reservoir of resources at Level 2. Here's the ones on Fluid Dynamics: Fitzpatrick's Fluid Dynamics. These ones are really good.

Fitzpatrick's Fluid Dynamics (Mechanics).

Level 3 (ArXiv)

As Jamie mentioned he uses plenty of papers. For anyone that isn't a member of a university, the workaround is to use ArXiv. This landed in The ArXiv Repository post way back in April 2013. There is a section devoted to Fluid Dynamics on ArXiv: Fluid Dynamics at ArXiv.

Fluid Dynamics at ArXiv.

Coding

Jamie also disclosed that life will be easier if you know how to code. I am still a believer that C++ is the best starting place for coding - The Pasture of C++ Notes post.

That Bit at the End...

It's one of the most fascinating places to see physics and mathematics factify and formulate the universe around us. Hats off to Jamie Nutter. This was Fluid Dynamics:

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The Academy-Keeping Corolary

The mission has been making some steady progress recently. But now it's time to start setting the sails to pick up some speed, but to do so, there needs to be a bit of house-keeping. The main place that needs an update is the lists. Now is the time for that academy-keeping.

Setting the sails of the muon Academy.

List-en Update!

The lists have rightfully been renamed to: List 1, 2 and 3, where 1 is the new starting level. These have been added to the header bar for quick access. List 1 was blogged here almost a year ago, but it's gotten a little bit hidden now. Even further back, I blogged about a page that Gerard t'Hooft constructed called "how to become a good theoretical physicist". The Gerard t'Hooft Theoretical Physicist Guide is essentially List 2. List 3, well that's the really tricky one. If you need a List 3 now, the Perimeter Institute advertise their syllabus online, this was blogged about in the Perimeter Institute Video Inclusion post. With great lists comes great new links and as the lists catch the wind, links to the relevant blog posts will be added to the lists.

Back to the Booty

Next time, in spirit of the second sentence of this post, it'll be fluid dynamics time!

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Into the Doc, the Horror

About a month ago, some typical rainy weather joined me as I set forth on the first day of my physics PhD. It started with the regulars: finding places, meeting people, making passwords, learning how to lift a box... then it really started. Like the blood on the bleeding walls of The Amityville Horror movie, the physics started oozing out. It oozes out thick and fast. The duty of the PhD student is to soak up as much physics as they can, construct it into some sort of original research and still be moderately sane as they tuck themselves into bed at night. It's a hard task. The PhD is three years long and, so far, it seems as though I need to be constantly running to finish in time.

Bleeding walls and physics in the Amityville Horror. 

Madness

My weekly timetable has developed itself into a medley of madness. I have meetings, seminars and lectures to attend. Then I teach undergraduates, mark their assignments, then do my own assignments. This is followed by the all important reading, researching and running simulations. That's why I'm still doing it at nine o'clock at night, flicking through articles or logged into the computer cluster. Speaking of which, if you're a Chromebook user, this SSH client extension will wake you from your nightmare and let you SSH. I was given a lot of advice on how to manage my time. Unfortunately all the advice was the same monotonous drone "read a book called 'How to Get a PhD', by Phillips and Pugh".

SSH on a Chromebook.

How to Get a PhD

Despite the name, which feels a little patronising, the book can be really helpful. It has some various tips and instructions on how to manage your research, what to expect of others, getting offered places and so on. Although you can figure out a lot of it yourself, it's much easier to just read it and save your valuable time and brain power. BRAAAAINS! Of course there's a reason I'm writing this, a Google search revealed that you can download the entire book for free from here!

The End, or is it?

It's that time of year when some of us start to think long and hard about what we're going to carve into a pumpkin. This year, if I don't carve something epic, I want to see something epic. Something physics-epic. Although this one was interesting, I'm not sure why the Einstein vacuum field equations were carved into a it...

Vacuum field equations... on a pumpkin.

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The Standard Model Standard

The moderately hungover first years were blissfully unaware of what I was about to tell them. For the past month I have been teaching undergraduate classical mechanics and this week I made an announcement. An announcement of the 2013 physics Nobel Prize winners. In an attempt of dramatics, I also told the tale of the Brout-Englert-Higgs boson, for it was Peter Higgs and François Englert who won the 2013 Nobel prize. Both for their work on the theory of the elusive boson that usually goes by the name of the Higgs boson.

A Belgian Boson

I was first told about the Belgian physicists Robert Brout and François Englert, by another Belgian physicist. In a flag waving moment, it was explained to me that Belgians exclusively call the Higgs boson the Brout-Englert-Higgs boson. The reason for this is that the mentioned Belgian duo invented and published the theory, independent of Higgs, only a few months before Higgs himself had. The duos' article can be found here, have a browse, it's in English. Unfortunately, Robert Brout died in 2011. He never got to witness the Brout-Englert-Higgs boson discovery at ATLAS last year, and as for the Nobel prize, well, you kind-of sort-of have to be alive for that...

The Standard Model

The discovery of the Brout-Englert-Higgs boson has been said to be one of the final pieces for the Standard Model of physics. This Standard Model is an attempt of a theory of everything - one theory that can explain every bit of physics. The Standard Model has proven to be highly successful, but it still doesn't play well with gravity. But, that doesn't hinder CERN's love of the standard model. They have it's main equation carved into stone:

The SM set in stone at CERN.

In honour of Brout, Englert, Higg and the Standard Model, here are some resources to check out the (Brout-Englert)-Higgs boson and the Standard Model.

Some Video Tape

To start light and short and at the Cranium level, MinutePhysics has a video about the (Brout-Englert)-Higgs boson (below), and about a theory of every thing (here).

Now to jump up in level to a Tibia / Mandible level for my favourite resource: PIRSA. Here's the link to the 2011 Standard Model course by Philip Schuster and Natalia Toro. I chose this year because I've watched every video from it, and they were rather epic.

The Standard Model as the Perimeter Institute sees it.

Some Notes

Staying at the Tibia / Mandible level, these notes are from a series of postgraduate lecture courses, by Professor Wing of UCL.

Alternatively, these ones from the University of Virginia, by Ivo van Vulpen, are more related to the Higgs boson: The Standard Model Higgs Boson.

The above two notes are the forte of this post. You don't need to use both, however, just the one that works best for you.

Previous Particle Post

A while ago I wrote an intro to particle physics post - The Particle Have Landed. The videos at the end are where I'm particularly wanting to point you, right now.

Vive la résistance: la physique!

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The Bucket Squirt Phys-elation

There are occasions when you can get hopped up on physics. You'll be taking it easy exploring a bit of physics when BAM! You find out about something revolutionary. Something like quantum tunnelling. It leaves you shocked and excited. Perhaps even sit-down excited. It's the physics feel good moment. A phys-elation. It's not the same as a eureka moment, but it is a good thing that happens more than once. Sometimes you'll know it's coming, sometimes you won't. But, they're pretty hard to forget.

Physics not drugs!

A Phys-elation Memory

Despite being hard to forget, I've never really reminisced about a phys-elation. Nonetheless, whilst writing The Seaside Physics Juxtaposition, a particular phys-elation memory crawled back to the surface of my mind. It was at A level, learning about circular motion. If you swing around a bucket of water fast enough, the constant change in velocity will force the water to stay in the bucket. However, if the bucket has a hole in bottom, water will squirt out of the hole... most of the time. If the holey bucket is being swung vertically, there is a point at the top  of the swing where the force of gravity can equal the centrifugal force that makes the water squirt out.

If you want to know the equation, the velocity for a squirt free climax has to be:

in which g is the acceleration due to gravity and r is the distance to the bucket from the pivot - your shoulder.

When the velocity is this value at the climax of the swing, water will stop squirting out. All standard stuff, no phys-elation at this point.

After learning this, we (the class) wanted proof, so we spent the rest of the lesson getting it. And we got it. This is our recording taken by a phone taped to a holey bucket of water being swung around.

It wasn't a eureka moment... but it was a phys-elation! You know what they say, small things please small minds, but not all minds pleased by small things are small minds... savvy?

The Circular Motion

If you want to look up any of the physics mentioned here, The Fitzpatrick Physics Files will direct you to a perfect resource for it. Specifically the Classical Mechanics notes.

That bit at the end...

The video above is courtesy of Skipper - it was his phone that recorded it. Skipper blogs over at Confessions of a Wildlife Biologist. You should check it out! Thanks to Skipper for risking his phone all those years ago!

Confessions of a Wildlife Biologist,

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The Vagabond Decision Algorithms

In the last blog post, I was in the scenically crowded seaside town of Whitby. Since that time I have packed my bindle and journeyed on southward. When it came to unpacking, I had to pause for awe. There was so much packed, it was ridiculous! But it reminded me of something. It reminded me of the bin packing algorithm. This bit of maths comes under the umbrella known as "Decision Mathematics". Of course, it's basically about making decisions using mathematical reasoning, such as with algorithms.

The Vagabond Decision Algorithm.

Decision Maths on the Cranium

Decision maths (DM) is something for the physicist, and something for the Cranium List. The reason for it making the list is that it's interesting, doesn't take long to pick up, and has links with quantum computing like with Shor's algorithm for quantum factorisation.

There are various resources that you could use to learn DM. However, I don't think that you need to spend 5 minutes watching a YouTube video about one algorithm when you could learn it in a single minute. Similarly, I don't think that you need to spend 5 minutes reading about an algorithm. So, here's the 3 resources:

The Student Room

Uncovered at Student Room D1 Revision Notes. It's well laid out, simply worded, has examples and has some video links. Unfortunately the algorithms are on different pages so you need to click through them.

The Student Room.

WikiBooks

Buried at WikiBooks OCR D1. This is a vague summary of the OCR course book for A level DM. (It's actually the book that I used.) The bonus of this resource is that the relevant notes are all one page.

WikiBooks

@ilovemathsgames

Also worth a mention is Decision 1 for Numpties. These are hand-written notes by a maths teacher (@ilovemathsgames). Although they have a good content, they remind me of when I would borrow girls notes at college!

Decision 1 for Numpties.

Final Words

Depending upon which part of physics interests you, you may never use anything from DM. But that doesn't mean you shouldn't know it, especially when it has quick rewards. Decision 1 is the first out of 2 modules in decision maths at A level. So you can dig a bit deeper if you like. As a final word, a good vagabond should know packing and route inspection algorithms, but unlike a regular vagabond, my bindle is actually a Peugeot 206...

That bit at the end...

It was very alarming when, 10 days after publishing this post, my blogger app decided to betray me. It completely removed the Vagabond Decision Algorithms post. As in, the entire post was lost. My day spiralled out of control. I was a lost cause. Hours later, submerged in empty bourbon cream packets and a tangled cardigan, I found some reluctant energy. Determined, I managed to discover a chrome extension that allowed me to load a cached webpage...  The Vagabond Decision Algorithms was back in the room!

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The Seaside Physics Juxtaposition

I grew up in an English seaside town. Dirty yellow boots, stinking scampi and tourists, lots and lots of tourists. I lived there until I was eighteen. Right now, I've found myself back in that seaside town where my physics cranium started. It's odd to look back and wonder why I got into physics. I'd like to say something elegantly epic like:

 "[I] wanted to be part of the romantic, exciting adventure to tease apart [the universe's] mysteries", 

as on Michio Kaku's website. But the truth is that that's a load of garbage. It's something that this seaside town nurtured overtime. This seaside town of Whitby, North Yorkshire.

A Physics Motivation

Some physicists would agree that their motivation for doing physics came when they were aged 16 to 18. For a lot of people in the UK, that's when they are studying their A levels. I did my A levels in Whitby, and it's true that they did play a major part in my motivation. But an interesting note is that A level is optional, so you need to like physics to choose physics to study physics. So what happened to me? What made me like physics enough to choose physics to study physics? Well, physics is everywhere. No matter where you look, some event takes place that involves physics. I think it's a possibility that I was tuning into seaside physics as an inspiration.

muon Academy flag!

Seaside Physics

The seaside is a non-stop physics puzzle.  Looking around at the tourists, I doubt many of them consider the collection of physics they are visiting.  If they were slow down for a moment, put their map book away, I'm sure they could be found staring with glazed eyes. It's my most used expression. The expression that I use when I'm trying to figure something out. These are some of the seaside physics that have given me, and still give me, that glazed eye expression:

• Do different flavours of ice cream melt at different rates?
• At which point would we consider a wave to start?
• Why do waves come above water and erupt in a frothy, foamy explosion?
• What made the cliff fall down, exposing old graves from St Mary's church?
• What's the point when sand stops being too dry or too wet to be made into a decent sandcastle?
• What's the best way to put a flag on a sandcastle without destroying the castle?
• Why is it more windy at the seaside than inland?
• How much altitude could that seagull have gained when it kicked my head? (Honestly, that happened a few days ago.)

...and that's not the end, there are more, lots and lots more, most of which remain unanswered. By applying theories of physics, there are lots of potential answers but rarely a firm conclusion. So despite being sure that the seaside has had some involvement, the reason I chose to do physics is, well, it's complicated.

That bit at the end...

Michio Kaku's website - why he became a physicist:
http://mkaku.org/home/?page_id=256

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The Thidé Book of EMT

An entire book on electromagnetic theory, free to download! That was my reaction when I found exactly that. It comes from a physicist who works at Uppsala University. A physicist named Bo Thidé, and the book, of course, is called "Electromagnetic Field Theory".

Electromagnetic Field Theory by Bo Thidé

I found this book out of necessity - I needed to look-up some EMT. It's the course book for a Classical Electrodynamics course at Uppsala University, so at least it has that reliability. It has also been recommended by Gerard t'Hooft, on the page that landed here.  To say a piece about the content, it's nice and concise, with a large mathematical formula section at the end. It's level is late-undergraduate and postgraduate - so Bones and Jaw. There's also an exercise book that can be found on the same website. It used to be available on Amazon, but it came with a cover designed by Albert Hofmann (well it looks like it was).

A garish existence on Amazon.

Before I found this book I didn't know about the Swedish city, Uppsala. Turns out it's the fourth largest city in Sweden, has some pretty impressive buildings and is home to the oldest Swedish university... yep, Uppsala University. This particular university once had it's doorways darkened by Anders Celsius, inventor of the Celsius scale. It's clear that Uppsala is a great city for it's own reasons, but for me, Bo Thidé has put Uppsala on the map.

I like this book!
Tack, Bo Thidé.

Links:

Download page for Electromagnetic Field Theory by Bo Thidé:
http://www.plasma.uu.se/CED/Book/index.html#download

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The Astronomy Virtualisation

It's difficult to not feel like dreamers when looking up at the night sky. Unless you're kicking it in the big smoke ... or anywhere that has a street light. That's because of light pollution. But you can freely defeat light pollution with a laptop, smartphone or tablet. I'm not talking about hacking the government, I'm talking of virtual astronomy. Below are three of the best methods of astronomy virtualisation.

Sky Map

This app's available on Google Play, hence it's for Android. When pointing it at the stars, it can feel a little bit "shaky", but it's got all the basic astronomy kicks to get you spinning. If you can see the stars in real life, Sky Map is a good way to check out what you're looking at, then you can say to someone: "Your eyes are brighter than Sirius... it's that one there", or something rubbish like that.

Sky Map.

Stellarium

This one's free for Mac, Windows and Linux and can be downloaded from the Stellarium website. Some planetariums actually use this program. It's really nice to be able to see what the universe looks like from another planet's perspective. But the best bit is going in spaceship mode and take yourself to the Moon and back.

Mars as the Mars Rover sees it, according to Stellarium.

Planetarium

This post is being written on a Chromebook, a machine which won't run either Sky Map or Stellarium. So as an alternative, you can use the Planetarium website. You may expect to have to log-in to the website, but you don't, you just load the page. It's also available as a Google Chrome extension. Planetarium is like Sky Map - straight up and simple.

Screenshot of the Planetarium website (set at a random date).

Of Interest:

Horrendous astronomy pick-up lines (where the "brighter than Sirius" one was found):
http://tehcip.wordpress.com/2013/01/17/astronomy-pick-up-lines/

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The Pasture of C++ Notes

A while ago I needed to learn a programming language. But which one? There's a lot to choose from. Baffled and confused, I took a piece of advice from a computer scientist friend: "C++, because once you learn that, all other languages will follow". Nice and simple, now to learn it.

A lot of graduate students will start their studies without knowing a great deal of programming languages. This means that when they start, they need to learn it. So most places put on computing lectures for these students as soon as they start and, most of the time, they put it on the internet.

The following resource is, as it says, from the DESY Summer School. The notes you can get are a pdf of the slides/handouts that were used in the lectures. As always, lecture notes are quick to the point and they won't go unnecessarily out of the way. For example, the language FORTRAN is described as VW Beetle, whereas C++ is described as a Formula 1. Nice and snappy, but I think a more amusing comparison would be a plain to one of those ribbed things... Regardless, here it is:

https://www.desy.de/~blist/summerstudents/c++-intro-10-offhandout.pdf

A drawback of the notes is that they may not go into enough detail. That's why you can use another resource along side it. The cplusplus website has a really good tutorial that you can also download as a pdf:

http://www.cplusplus.com/doc/tutorial/

To actually do the code you need a compiler. So I followed more advise from the computer scientist friend: "use Linux because it just works" - Ubuntu and g++! If you aren't a fan of the above two resources, try these out too: C++ Intro and C++ Reference.

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The YouTube VT Round

Sometimes I cringe when I think about all the time that I’ve wasted on YouTube watching the sneezing panda video. But, YouTube has a lot of physics videos too. The only problem is, it also has a lot of crap physics videos. With a little bit of exploring, you can uncover the really good ones. Here’s some of the best ones that you can watch in less than 5 minutes.

MinutePhysics

By searching physics, the MinutePhysics channel actually does have a high chance of coming in the top 10 results. It’s not surprising really, as it’s easily the best channel that explicitly states physics in the name. The videos are just a hand drawing simplistic cartoon pictures, whilst a voice narrates you through. A nice aspect of this style is that the voice feels right, in a way that a voice like Extreme Makeover host, Ty Pennington, simply wouldn’t. Neil Turok has done the voice on at least one of the videos (he’s the director of the Perimeter Institute). Without going into heavy descriptions, MinutePhysics is able to explain some hardcore topics. Take parallel universes for example:

Smarter Every Day

The Alabama man behind SED is called Destin. His mantra is “I try to get Smarter Every Day, and make fun science videos sharing my progress”. He spends a lot of time on his videos, and you can really tell. His friends and family once had intervention with the theme “Bro’s before YouTube”. I know this because he recorded it, and put it on YouTube. Regardless of the intervention, there’s some diamond VT on his channel, this was the first one that I ever watched:

Others

Often I've come across some VT that's looked ridgy didge, but has gone straight onto the junk pile. In particular, the 100 second videos by Physics World - so so boring. Here's some other good videos of interest: Veritasium, Fermilab and, if you feel brave enough for the Glasgow accent, Glesga Physics. 

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The Perimeter Institute Video Inclusion

The Perimeter Institute is the Black Pearl on the theoretical physics ocean. Among its’ crew are some of the leading researchers in particle physics, string theory, cosmology, condensed matter and quantum physics. So, when the Perimeter Institute do lectures or seminars, you expect them to be pretty good ones. Amazingly, you can make this decision for yourself as you can access every single recorded lecture and seminar from their website for free. And they record everything!

The PIRSA website is where the action happens. PIRSA stands for “Perimeter Institute Recorded Seminar Archive” - which is rather self explanatory. On this website, you can browse through the entire archive of videos. Some of these videos are public outreach, some are colloquium, but the majority are from their masters courses in theoretical physics. So it's applicable to all levels. Splice the mainbrace! (Apparently that mean to give the crew a drink.)

The masters course is really intense, but you’re able to just stroll through the lectures in your own leisurely time. There are 4 parts to the course:

1. "Mathematical Review" - reviewing mathematics such as group theory and complex analysis. A man who goes by the name of Tibra Ali does the complex analysis course and he does a really good job of it.

1. "Core" - essential physics that’s needed for understanding heavier topics, such as string theory.

1. "Review" - this is pretty much a review of the areas of research at Perimeter. This is where you get to see courses on string theory and cosmology and all the others.

1. "Explorations" - again, this is to do with the areas of research at Perimeter, but the focus is now on current research.

Here’s the lecture list from the 2011/2012 academic year. Although they go on every year, I found the 11/12 ones the best - the most recently completed.

The non-course videos are also really good. One of my favourites is by Cliff Burgess, a particle physics researcher who, on his homepage, describes himself as "one helluva guy", and he is! In this VT, he essentially “gases” about why particle physics is the best research area.

The main piece of advice from the above VT is to, when it comes to physics, "follow your nose". Sniff. Sniff.

PIRSA website:

http://pirsa.org/

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The Academy Renamed

It's finally happened! mmxi Academy has been renamed to:

muon Academy

a name that breathes a refreshing hint of physics without being stupidly obvious.

The muon bit

Of course, a muon is a fundamental particle. At the time of it's discovery around the 1930s-40s, the Nobel laurette, Isidor Rabi, made a catty comment about the muon:

"Who ordered that?".

Me-ow. Well, the reason that he said this was because the muon seemed obsolete. It wasn't necessary in any nuclear interactions that they knew about at the time. But right now, the role of the muon has changed a lot. The celebrity particle accelerator, the LHC, has a large involvement with muons. One of it's main detectors is called the compact muon solenoid, which was heavily involved with the discovery of the Higgs boson. This is just a small taste of what the muon involves itself in. It's amusing how much physics has changed, and continues to change. (Entry 10 of the Skull List - Evolution of physics - shoots at these changes.)

At the end of it all...

... times change and people change with them. And as a result, I didn't like the old name, so a I got a muon - it's physics, savvy?

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The Cambridge Cosmology Consequence

Cosmology is a beautiful thing; so is Stephen Hawking. He’s done a lot for cosmology, so much that he has a research centre at Cambridge named after him:

The Stephen Hawking Centre for Theoretical Cosmology.

The good thing about Cambridge is that they have an enormous amount of money. Their total financial endowment is in excess of £4.3 billion! With this money they make pretty websites to exemplify their research and knowledge. The CTC website is a beautiful example of this.

On the CTC website there is the outreach pages, complete with really good explanations and diagrams of all manner of cosmology. The level of content is Bones, but it can also be Skull with a good use of their glossary.

http://www.ctc.cam.ac.uk/footer/glossary.php

Here’s the section headers for the pages:

• The Big Bang
• Galaxies
• The Cosmic Sky
• The Early Universe
• Quantum Origins
• Black Holes

My personal favourite is the early universe section as it has a lot on string theory. However, the big bang section has a really good page called “A History of Ideas”, which gives little summaries of the turning points in cosmology, such as discovering the cosmic microwave background.

http://www.ctc.cam.ac.uk/outreach/origins/big_bang_two.php

It’s actually one of the most pleasing websites to browse that’s on the muon Academy blog. With a bit of digging, you may uncover some decent links too. To finish on, here’s the most amusing graph on the CTC website (if you have an inner child):

The Stephen Hawking CTC Outreach source:
http://www.ctc.cam.ac.uk/outreach/origins_of_the_universe.php

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The Arxiv Repository

The function of a researcher is to write articles for big and expensive journals, such as Physical Review Letters. After this, the institute that paid for the research looks good and their respect goes up (like a gang in GTA). At least, that’s the hope anyway. In reality, the process is best summed up by the Mumford and Sons line: 

“Crawl on my belly ‘til the sun goes down.”

but perhaps that’s only due to my choice of music as I write. Regardless, here’s the main problems:

1. Only people who have access to a paid subscription for the journal, can read the article.
2. The time between submission and publication is far too long - a duration of months.
3. The article may be considered not good enough to be in the journal, by the journal people themselves. (I’ve heard of an article being rejected because “there’s no such unit as a kilo Wu”.)

So here’s the fix, articles are initially submitted to the Cornell University website: ArXiv. There’s a vast amount of physics research on ArXiv (arr-kiv), neatly organised by topic.

Here’s the best features:

1. Everyone can access the research from the website for free.
2. Submission time is essentially instantaneous.
3. Research will be accepted!

Now there are drawbacks to ArXiv. To me, the main drawback is that you have to decide for yourself how reliable an article is. It’s possible that some clown has submitted a load of rubbish. The reason why researchers use ArXiv was mentioned by Brian Greene in his book: The Elegant Universe. Although he didn’t mention ArXiv explicitly, it’s pretty obvious that he was referring to it when he said that it’s the quickest option for distributing his work. (See the Jaw link at the bottom of this page for this article.)

Eventually, the articles usually find their way into one of the big and expensive journals (for the respect). But my own opinion is that the big and expensive journals are like broken crowns. Whereas ArXiv is another road, and you can take that road and you can fuck it all away. 

Actually that last bit was Mumford and Sons again. But ArXiv is relevant to all Skull, Bones and Jaw - all of physics. There is such a variety of papers and it is really worth a look.

Here’s some interesting papers:

Skull level - space travel:

http://arxiv.org/abs/astro-ph/0509268

Bones level - the new standard model:

http://arxiv.org/abs/1212.5190

Jaw level - the article by Brian Greene (interestingly you can see that it was shortly resubmitted - as mentioned in the book):

http://arxiv.org/abs/hep-th/9504145

ArXiv:

http://uk.arxiv.org/

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The Fitzpatrick Physics Files

There's a character in The Big Bang Theory who looks like a praying mantis. This character is of course Sheldon Cooper - a child prodigy from Texas. Texas has given us more scientists than just Sheldon, take Sandy from Spongebob for example. There is too much evidence for this to be a coincidence. It's something to do with Texas. I think the  University of Texas man, Richard Fitzpatrick, shares some of this responsibility, as he has written some pretty damn good physics notes on his website.

Now, he has actually covered a lot, and it's all at university level. Here's the full list of what is written on the website:

• Plasma Physics
• Quantum Mechanics
• Classical Electromagnetism
• Quantum Mechanics
• Thermodynamics And Statistical Mechanics
• Classical Electromagnetism
• Fluid Mechanics
• Newtonian Dynamics
• Computational Physics
• Oscillations and Waves
• Electromagnetism And Optics
• Classical Mechanics

I can actually remember using the Newtonian Dynamics section to find answers to my homework, 4 years ago. One thing to be aware of is the dull appearance. There are no pretty pictures, the font is ancient and there isn't any colour! Fortunately, it is really well laid out.

Here's a screen shot of the computational section, to see what I mean:

Every thing that has been written has been written carefully and put in the right place. It's also downloadable as a PDF, so you can save it to read without an internet connection. Go crazy!

This is it:
http://farside.ph.utexas.edu/teaching.html

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The Grim and Gravity Connection

Gravity makes getting up in the morning difficult, it’s also responsible that unpleasant kiss of the curb when you've had too much to drink. Well, gravity and alcohol is. With gravity affecting so much of our life, you would think that it was easy to figure out, but it really wasn't, and still isn't. It’s story started over 2000 years ago, and involved a surprising amount of misery and death.

A Greek Conquest

We'll start with the ancient Greek man named Aristotle. During Aristotle's’ era of the 4th century BC, death was a common occurrence, it was a time of conquest and harsh punishment. His mentors’ mentor, Socrates, was executed simply for questioning nature. Aristotle's student, Alexander the Great, had led numerous opium fuelled conquests before he suspiciously died. Suspicions that caused Aristotle to flee from Athens, fearing the same fate as Socrates. During this seemingly chaotic life of Aristotle, a fair amount of work on what we now know to be gravity was done. Aristotle realised that motion depends upon the nature of the object, in a sense that fire would go up, earth would go down. Although it seems rather mundane and basic (and wrong), Aristotle's work was a step towards gravity.

A Post-Dark Age Pandemic

After Aristotle, there was a dark age where not much happened. But the dark age did come to an end, and from the 14th to the 17th century AD, the black death bled across Europe, shattering the population. Amidst the plagued cities and dropping bodies, Galileo Galilei was on top of the leaning tower of Pisa dropping objects. Galileo, perhaps the only scientist that we know by their first name, discovered that an object's acceleration towards the Earth does not depend on it’s mass. If it wasn't for air resistance from the atmosphere, we would see a feather fall to the ground as fast as a hammer does. Unfortunately, Galileo's’ work angered the church. A “suspect of heresy”. He was sentenced to spend the rest of his life imprisoned in his own home, where he died in 1642 - the very year our hero of gravity, Isaac Newton, was born.

A Red Cross London

As the 1665 great plague of London splattered doors with red crosses, Newton's door remained clean. Buboes were violently growing on terminally ill Londoners, but he was safe living in the country. It’s at this time that Newton is believed to have been inspired to work on gravity by an apple falling on his head. Although the tall tale of the apple is more unbelievable than Azealia Banks lyrics, a branch from the supposed apple tree now grows at the University of York. Through his work, Newton realised that the force of gravity between two objects depends on how far away they are, and how much they weigh. So, this is why the Earth has an atmosphere but the Moon doesn't, as the Moon is too light to have a gravity strong enough to hold onto the one. More familiarly, it’s why staying stood up can be hard,  as we have to counter the Earth pulling us back down. 

That bit at the end...

The theory of gravity has had slight changes since Newton, but his work is still used and taught now. It is only extreme conditions, such as near a neutron star or when travelling 1,000,000 mph,  that Newton's work becomes invalid and the slight changes are used. However, when we look deeper and deeper, smaller and smaller, it becomes apparent that gravity still needs tweaking for particle physics. Fortunately, those small and extreme conditions are small and extreme, so Newton’s gravity is like your everyday pair of converse.

Newton's shoes?

A website with a lot of information on Galileos life:
http://galileo.rice.edu/chron/europe.html

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