I'm bored, someone explain theoretical physics to me...

warning: it will break yr brane

"time from the beginning" is interesting even if the math is a bit hard to work out

ppl keep dropping stuff into conversations round here like "if you integrate round the boundary of string theory then you get quantum field theory". i can never remember the precise statements though.

some notes by a friend of mine that are supposed to be pretty good:

http://math.berkeley.edu/~barnard/tex/getpdf.cgi?qft

if you get past the integral signs on page 4 there's some nice historical stuff, anyway.

what's the name of it?

sounds quite similar to PKD's 'A scanner darkly'

why didn't you like it?

Who wrote Scanner Darkly? Is that William Gibson? Don't think I like Gibson, for some reason, never seem able to get more than 4 pages into any of his books, though I've not tried lately.

Hard Boiled Wonderland is AMAZING so far. Wish I could do that accounting thing where he separates the two hemispheres of his brain so he can tabulate more quickly, that would be REALLY useful around here!

I'm going to a lecture here at UCL tomorrow on one theory of the way the brain works, known as Functionalism, so I will try to remember to report back if it's interesting. Yesterday's on Oh No! Giant Tsunamis! Oh No!* was drier than I'd expected - it had no artist's impressions or animations of NYC being overwhelmed by 500 foot tidal waves or anything, which seemed like a major lost opportunity.

* possibly not its actual title

The bumblebee thing is my second favourite scientist-proving-flight-impossible tale. One scientist 'proved' that manned flight was impossible, and the ink was barely dry on the paper when he was proved wrong. When challenged he was flustered for a moment, but rallied with "Well okay - but they'll never do it with a passenger."

(not naive functionalism obv, tho it is generally ace)

(possibly the spookiest bit of film i have seen in a documentary for years)

In a very real sense we are no more than New Year Waves in the quantum foam of life....

Proof: voila ilx qed

i read "hard-boiled..." it's grebt! I'm reading "Wind-up Bird Chronicles " right now and I love it equally. There should be a Haruki Murakami thread if there isn't one.

On to physics:

Einstein's relativity in words of four letters or less

I think the most interesting stuff going on today is complex systems theory.

here

cybernetics

http://www.mathmistakes.com/ may be fun and fulfill your desire.

http://www.edge.org

A Cosmic Microwave Background image of the atmosphere:
http://nssdca.gsfc.nasa.gov/anon_dir/cobe/images/dmr/CMB_FLUCTUATIONS_SML.JPG

Pretty Pics from the Hubble Space Telescope

Ned Wright's Cosmology Tutorial

Mexican Wave Theory

Okay - I understand that in the attempt to understand gravity, Einstein had us imagine the universe in four dimensions, as a flat plane, with dense objects sinking into it. Am I okay so far? Right, now, it seems fine now to imagine that objects like the earth would roll around the sun, much like a coin put into one of those swirly charity things. But isn't this just gravity again? Hasn't he just used gravity as a metaphor for gravity? I mean, I know why things roll into dips, and around the edge of such things...gravity, surely? So, what am I missing?

It's an interesting thread, sure, but still. I'm worried about the holes I have in my memory.

Kevin, what do you mean gravity again? Einstein is demonstrating how gravity works, in an understandable, simplified, quasi-2D way - he's not saying *why* it works. Gravity is, as far as I can tell, the most difficult of the fundamental forces to explain - there was a lot of interest in the odds of a gravity particle being discovered in the next few years - the original odds of 500-1 were reduced to single figures when the bookies started taking a lot of bets on it. But we're not even close to discovering the Graviton, even if such a particle does exist.*

*I don't know very much at all about the subject so please forgive glaring inaccuracies

Mark, one of the main things about SR is that *nothing* can travel faster than the speed of light in any given inertial frame. This means objects can only 'communicate' at the speed of light, so any action in one that may affect a second can only be known about by the other second after an interval equivalent to the period of time required for light to reach it from the first.

Because a fast-moving object is fast only in relation to a slower one from the pov of a third object, there's no such thing as a shorter life-span either. The universe doesn't end at some point - the universe has no boundary because it is the sum of everything.

It is expanding, though. Imagine that the universe could be plotted on the skin of a balloon (and in the 3D space enclosed by the balloon). Inflate the balloon a bit and everything gets further away from each other. But the distances between points can only be expressed as the relationship between the points.

Is that analogous?

Nevermind, just found it in Blake on a hunch.

* which is a lot of things, because most of the applications we have that are front-ends to databases use Crystal for their built-in reporting. And this particular machine was in the accounts department, so had a copy of every single one of these apps in order to run their accounting reports.

** yes, I know that this is an installation thing, and if we'd wiped the machine from scratch and reinstalled it on a blank disk then it would work. Hopefully.

Brian Greene? As in the Elegant Universe? A lovely book, I just finished it last week. Is there another one? Someone told me there was.

I'm fine with relativity, it's got to the point where it's become second nature to me. (Funny, the first time I read Hawking it went straight over my head, but 5 years later, it seemed almost obvious.) I'm one of those dummies who can't think about Quantum Theory without getting dizzy, though.

String theory just makes me happy because of the idea of extra curled up dimensions. It seems either better explained or easier to get my head around than Quantum Theory.

Quantum Mechanics is one of those things where it seems almost like I have to take my brain out of my head and wrap it physically around the idea, like trying to stretch a condom around a basketball, I can just about hold it in my head if I try really hard, but then it just slips away from me the moment I stop concentrating.

Ah yes, The Fabric of the Cosmos: Space, Time, and the Texture of Reality I need to read that now.

But I know that they are cleverer than me and have probably already thought through that. :-(

(Can you tell I'm just frustrated cause they haven't let me at the hyper-dimensional data cubes yet?)

it is one of the tragedies of my our existence

FUCK YOU EINSTEIN!!