New Zealand born photographer Max Alexander has taken a truly fantastic set of portraits of a number of astronomers. These are just two of them -- go to his website and have a look at the rest!


With thanks to Astropixie for the link!

Ladies and gentlemen, have a Happy Carl Sagan Day!




Ps: I'll write some proper blog entries again soon, I promise!

This has been stuck in my head all day long. How strange! It's on my current ipod playlist. I even feel compelled to pick up my ukulele and learn how to play a cover of it -- which is rare occurence for something that came from the depths of YouTube.

In other words, this is probably the best tribute I've ever seen to the greatest astrochemist of all time. The world needs more people like you, Carl.



A still more glorious dawn awaits
Not a sunrise, but a galaxy rise
A morning filled with 400 billion suns
The rising of the Milky Way

Pluralitas non est ponenda sine necessitate.
(Plurality is not to be posited without necessity.)



There are a number of principles in modern science which are quite pivotal for how science itself works. Principles which can often be used to distinguish the scientific from the psuedoscientific. Principles with which sound theories can be constructed and tested. One of the most pivotal of these is surely Occam's razor.

Attributed to an English friar and philosopher, William of Ockham, the strict translation above might not be the most intuitive. All the same, the bottom line is simple. A good theory or hypothesis will be the one which requires the least assumptions. If you require the existence of some additional, hitherto unknown, entity to make your theory work, you'd better have an exceptionally good reason for doing so. Simplest is best. It's been found time and again that the Universe has a tendancy to work that way, which is why many theories in physics are elegantly simple. Describe the most data with the simplest explanation possible. Hence, it's referred to as a "razor" -- for cutting away any unnecessary material.

Newtonian mechanics is quite a good example. More commonly known as classical mechanics, it's simple enough that you were probably taught some principles of it in primary school, Newton's laws are, to all intents and purposes, an ideal description of the world around us. Simple, however, does not mean simplistic. Classical mechanics are still widely used in the world today.

Newton's laws, however, failed to describe everything. In particular, they didn't perfectly account for the orbit of Mercury around the Sun. Nor could they -- this required information that Newton never had. Mercury's orbit was only properly explained by an equally elegant theory. General Relativity. As anyone who's studied it will attest, relativity can become exceedingly complex. The genius of it though, is that this manifold complexity stems from what is, in essence, a beautifully simple concept. Einstein's own philosophy was to view the Universe as "made from marble." Pure and pristine. He believed the true nature of the universe to be a beautiful thing. Simple and smooth. Not like the coarse and discordent theories employed in some areas of science, which he referred to as "wooden."

Thus, Occam's razor allows for an evolution of ideas. Any given theory is eventually superceded by another, explaining the shortcomings of the first in as simple a manner as possible. It's certainly true in physics that many fervently believe the simplest theory to be the best. And therein lies the rub.

The so-called "standard model" of particle physics is arguably the most successful theory of all time. Describing the quantum world with precision and consistency, the standard model is our best description of the bizarre world of quantum mechanics. But by all standards, it's gut wrenchingly ugly. By Einstein's definitions, the standard model is very definitely made of wood, with all of its lumps, bumps and knots clearly on display. No matter how carefully you sand down a wooden theory to smooth it's edges, the knots will still remain. The quest for a marble theory is one of the driving factors behind the search for grand unified theories -- but thus far, few can fully withstand the test of Occam's dreaded razor. All must posit new entities or realities, many of which are simply untestable.

Another interesting thing is that Occam's razor is the main armament of any theorist who's critical of dark matter. Dark matter was proposed to explain why galaxies don't simply fling themselves apart. They rotate far faster than they theoretically should unless they're significantly more massive than they appear to be. The idea of dark matter, then, is simply that they are significantly more massive than they appear to be! Dark matter is, arguably, a quick fix. Not enough matter? No problem! Let's just assume that there's a lot more matter there. We just can't see it. Not an unreasonable suggestion in all fairness. Those critics, however, prefer to believe that we simply don't understand gravity as well as we could. Theories like Modified Newtonian Dynamics (MOND) have been proposed as a result, which don't require the presence of dark matter. It has to be said, applying Occam's razor, such theories should be favourable -- they require fewer assumptions.

No one theory has yet been universally accepted (neither to solve both the galaxy rotation problem, nor to supercede the standard model), and many of the most widely used have difficulties. It's been said that physics is overdue for a major breakthrough. A Richard Feynman for the 21st century, perhaps. For the meantime, we just have to sit back and wait for some plucky theorist to find the shoe that fits best.

I've actually known about the blackboard in a certain seminar room in the School of Physics for quite some time now, and I've been meaning on going there and photographing it for almost as long. Well, finally I figured there's no time like the present, so I took 10 minutes out of my day to go and take some snaps. Purely because I could.

Unfortunately, the blackboard also seems to be housed behind some of the most reflective glass known to humanity, which isn't too helpful when you're without a polarising filter...


At risk of verging on hero worship, it's actually rather humbling to know that Einstein himself wrote these words. It's just a pity I can't read German, so I don't really understand what's been written.

( A couple more... )


My little exeunt, incidentally, was prompted by local chemistry hero, Martyn Poliakoff's recent video...

In case you've somehow missed the phenomenon that is Periodic Videos, I'd highly recommend you go there and check out some of the others!

(And yes, Periodic Videos is filmed in the same School of Chemistry where I work.)

Oooo... BBC Radio 4 are going to be airing a tribute to Carl Sagan, presented by none other than Brian Cox.

I'd write more, but instead I'm going to direct you over to Astro Engine where Ian O'Neill has already written everything you need to know!

EDIT-- The archived show is listenable here.

(Incidentally, I discovered this news snippet via Twitter! Ah, I knew it would have its uses...)

I saw this on Bad Astronomy, and I just couldn't help myself!
(I quite literally laughed out loud!)



More geeky Valentine's Day greetings from Ironic Sans.

A very happy 200th birthday to Mr Charles Darwin!



Perhaps it's a fitting birthday present that The Catholic Church, so it seems, are being very amicable towards the concept of evolution.

To quote a few choice cuts directly from that link:

"What we mean by evolution is the world as created by God."

Did I say this? No. It was reportedly said on Tuesday by none other than Archbishop Gianfranco Ravasi, head of the Vatican's Pontifical Council for Culture. In effect, the Roman Catholic Church, the dominant Christian faith, is saying that Darwin's theory of evolution is compatible with Christian faith.

...

Furthermore, they're going to be discussing the relationship between evolution and faith next month in Rome at a special conference to mark the 150th Anniversary of Darwin's Origin of Species which, as we know, changed forever our views about how we came to be here on this little planet.

...

As a passing thought, Ravasi said that Darwin's theories had never formally been condemned by the Roman Catholic church. Pope Puis XII said in 1950 that evolution was a valid scientific approach to the development of humans. John Paul II said in 1996 that it was "more than a hypothesis".

A very interesting turn of events. Maybe everyone can get along after all... I certainly hope so!


Image seen on, and promptly yoinked from, One Astronomers Noise

It's been snowing on and off here all day. I love snow, and the fact that some of it is settling makes me happy! I went out for a walk in it before (mostly to get some firewood). It's lovely being surrounded by swirling snowflakes.



The actual snowflakes themselves are quite beauiful too. Hexagonal crystalline forms, created because of the way water molecules bind to each other when they crystallise. Crystallising in the air (homogeneous nucleation) makes them form the beautifully symmetric dendritic structures that we all know and love.

The image is from the Bentley Snow Crystal Collection, hosted at the Buffalo Museum of Science. If you have time, go and have a look. Some of them are beautiful! They were originally photographed by Wilson A. Bentley, pioneering scientist and photographer -- and the first person ever to succesfully photograph snow crystals. His first photograph was taken in 1885. The images on the website (and those at the museum itself) are his unaltered original images, taken on glass slides under a microscope.

Truly beautiful.