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Einstein's Theory Improved?
skaet writes to tell us that A Chinese astronomer from the University of St Andrews claims to have fine-tuned Einstein's theory of gravity. Dr Hong Sheng Zhao has created a 'simple' theory which could "solve a dark mystery that has baffled astrophysicists for three-quarters of a century." This new law seeks to discover whether Einstein's theory was correct and if dark matter actually exists.
I second that sentiment, and presume that he means it - with the publication of not just his office number, but his personal mobile (cell) number as well!
"There is nothing nice about Steve Jobs and nothing evil about Bill Gates." - Chuck Peddle
I did go there --- it's a great place (and the bright red gowns are no longer compulsory, although you get free entry to the castle if you wear your gown). I did first year astronomy before realising that my maths weren't up to it and switching to comp sci; St. Andrews has some genuinely decent telescopes despite being at sea-level in a built up area. The Greg is deeply impressive to go and see. It's amazing just how big it is.
For those who don't know, St.Andrews is the third oldest university in the UK, after Oxford and Cambridge; it was founded in 1413, and totally dominates the town. (The university owns most of the town centre.) Going there is an experience totally unlike any other university in Britain... I had a room in a hall of residence five minutes walk from the town centre, perched high on a cliff top overlooking the North Sea. Great view.
Unfortunately, like Cambridge, St. Andrews has suffered from negative publicity as a result of its taking occasional pupils from failing schools and admitting them with A level scores which would not normally allow a student to be admitted. But at least it meant that some of the Windsors got access to higher education, so perhaps the policy is defensible.
Actually, things have changed. Until very recently, British students got their tuition fees paid by the state. Not long ago, however, the British parliament voted to make them pay a proportion --- but the Scottish parliament didn't. So students who go to a Scottish university get their tuition fees paid for them. As a result, all the Scottish universities have been inundated with students, and as the highest-prestige university in the country, St.Andrews can now basically name their price.
That doesn't explain Prince William, however, who is by all accounts not very bright.
A word about semetic languages like Hebrew, Arabic, and Amaharic: they have a rich infix morphology. What this means in practice is that various inflections of Hebrew words (an English example of inflection is the addition of -s to the end of a verb in the third person, for example, I say versus he says) involve swapping the vowels in a word (but the consonants stay the same).
Indeed, most verbs in Hebrew have a three consonant "root" (some have two). Depending on the tense, person, number, and gender of a verb (Hebrew verbs, unlike say, French verbs, agree with the subject's gender as well as number), the vowels in a Hebrew verb will change (and a prefix or suffix may be added as well).
All of this is just a roundabout way of saying that any word with say, a k-t-v root will have to do with, in this case, writing, whether it's katav or kotev or what have you.
This is why all semetic languages evolved writing systems where the vowels are generally not written: vowels simply don't have much semantic value in semetic languages. It may seem weird at first, but it's actually rather logical if you're exposed to it for a while.
Now, I'm not Jewish, so I don't know exactly, but I remember reading that the religious texts in fact were marked with the vowel diacritics -- that in fact, the vowel diacritics were invented for the sole purpose of reminding Rabbis how the texts should be read, as Hebrew was a dead language for a millenium or more.
Native speakers have little need for them, as it is clear from context what the vowels should be. Thnk abt t, vn n nglsh y cn ndrstnd lrght, and in English the presence or absence of vowels can actually change the root meaning of a word!
Anyone who is actually Hebrew-speaking and/or Jewish feel free to correct me. My Hebrew is very bad.
The problem is that as a result physicists really, really like very elegant theories when there's no particular reason to believe that the Universe itself has the same bias. Similarly, we like to take theories that work on scales and locations that we know and can easily interact with, and assume that they smoothly apply in the places that we can't get to know quite so easily. It's reasonable even if it isn't logical - we have to go with what we already have. It's a decision born of practicality.
In Cosmology, there's even a phrase for this: we assume homogeneity and isotropy. That is, that there's nothing special about where and when we are, and that the universe is pretty much the same (in physical laws) everywhere. The first time I heard about "dark matter," it was in the context of closure of the Universe. Physicsts really really wanted the universe to have enough mass/energy in order to be "closed," but we simply weren't finding enough matter. There was no reason to believe that the universe is closed (curvature 1.0), but it just seemed more elegant. So, they started to look for the "missing mass."
These are not logical assumptions, they're just assumptions that we have to make in order to get anywhere. Again, there's no reason that the universe will cooperate on this matter.
My own bias is to reject dark matter in favor of a revised theory of gravity, but that's just my own love of elegance - a different gravity feels more elegant than dark matter and dark energy, and in fact would hint at much more interesting cosmologies. But that's just how I am seduced by elegance...
"It is our blasphemy which has made us great, and will sustain us, and which the gods secretly admire in us." - Zelazny