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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The Particles Have Landed

Everything that we see is made from fundamental particles. Well, that's what everyone says at least. Unfortunately, the term "fundamental particle" has become somewhat of a cliché in physics! Starting with a cliché is not a very clever thing to do as the very meaning is lost straight away, however we can fix that and keep a good tight hold of the meaning (it's important).

Fundamental particles are very interesting, but what is meant by "fundamental", and what is meant by "particle". We see what they mean via the free and friendly Google:

We get to the answer by piecing these definitions together: very small pieces of matter that form the basis of all other matter. So they actually do make everything in the universe. This is why particles should be the first step for someone learning physics.

The usual analogy that follows is to say that fundamental particles are like bricks in a building. Let's not go down that street. Let's instead opt for a more colourful analogy. Here's an analogy that you may be more familiar with:

The process of courting

With the help of some modified Minus the Bear lyrics, picture the following scenario:

10 at night you're sat in a bar,
well-dressed with a drink in hand.
A girl you know, lights up the room.

All the boys are begging for her,
trying hard to grab her beauty,
to throw some charm that won't win.

It's strange, this girl, she's looking at you
You glance up then down at her drink.
The truth is, she's got the idea.
She's got the right idea.

So, what were the fundamentals of this courting process? 

Beauty - Either as physical or personal attraction.
Charm - Courting usually has some charm.
Strange - The feeling if it starts to go well.
Up - Suggestive look (or something else), usually before...
Down - Suggestive look (or something else).
Truth - The fact of success, if it's gone well.

Courting can be done with all or just a few of these fundamentals.

The punchline of this analogy is that all of those fundamentals are actually the names of real fundamental particles, collectively known as "quarks". (Although Truth and Beauty are more commonly known as Top and Bottom.)

There are many more fundamental particles than those six quarks. But you don't need to learn them all, you just need to appreciate their importance. A good follow up to is to watch "A Crash Course in Particle Physics" by Professor Brian Cox. Professor Cox is particle physicist and former keyboard player of D:Ream (things can only get better...). He has played a large part in advancing physics in the media, and he is also one of the sexiest men in the world, according to People Magazine. Perhaps he takes part in a lot of "courting"!

Stay tuned for your next Skull particle fix.

Seattle rock band, Minus the Bear, website:
http://minusthebear.com/

Professor Cox as one of the sexiest men:
http://atlas.ch/news/2009/sexiest-physicist.html

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