h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

*nothing* wrong with your grammar, and pretty good certainly in favour of very, please.
I like to keep taps on everyones pages, I update mine and I like to check on other page's changes, too, so that if you've written a new guide entry, say, I get to read it straight away!
Joanna-the-many-who-is-one

Joanna-the-many-who-is-one ... that could stick. I asked the question because your message must have arrived literally within a minute of me updating the page. Spooky or what?

Hope you like my serendipitous new features, although it seems that less than 1 in 10 of all article numbers actully have live links. Perhaps we should get your holistic detective friend on the case.

It is interesting to me how relatively constant is the number of people who are on-line at any one time. I've never found less than 20, or more than 50. Statistically, you would expect a fairly narrow range, although I guess I'm surprised it's as low as it is. Especially when you consider how busy just your donut stall can be.
What are your observations, many-who-is-one?

The constancy of the no. of researchers... I have seen it as low as eight, during the holidays in the day time. If there's too many access times get slower, so people drop off. I guess the number of people logging on and off is pretty constant, though.
I do like your features, very impressive
Joanna-who-knew-she-shouldn't-have-typed-many-who-is-one-as-she-typed

Indeed! I'm signing off for the night. Good to touch base with you.

I hope you'll use this forum to keep in touch about your quantum theory lectures. I'm very keen to hear what you make of renormalisation.

Don't forget to get some sleep.

Not quite re-normalisation yet... but we had a fascinating lecture today on Solitons... They exist on the M25, according to the lecturer!
Apparently there was a bad accident, resulting in a tailback; when the accident cleared it resulted in a density wave of traffic travelling in the opposite direction at 39mph! It got round about eight times before there weren't enough cars to sustain it! Perhaps physics isn't such a bad thing...

Sounds like Physics lectures are a great deal more interesting than in my day. Your description painted a really clear picture. Certainly the most interesting thing about travelling on motorways is observing the traffic wave patterns - as long as they're not stationary waves. This feature of the traffic density in one flow having a subtle effect on the flow in the opposite direction is particularly fascinating, and the question of a critical traffic density to maintain a waveform. You're making me envious.

Oops! I meant that the cars were travelling in one direction while the wave travelled the opposite direction in the same stream of traffic
Apparently a police helicopter overhead first noticed it.
I once read somewhere (probably New Scientist) that cars would move faster on a motorway if there were more of them... they would then stop behaving as many different entities and become one!
Don't be envious of my lectures... If you'd had your brain fried in Single Mathematics B you'd not think very kindly of them...

Habit of mine. Creative reinterpretation - although there is a well known effect when there is an accident, where a retarded wave can bring traffic to a halt miles before an accident scene, caused purely by drives slowing to 'gooseneck'. I was thinking how wonderful it would be to observe these waves from the air. I love this kind of emergent phenomenon.

Perhaps I don't really envy you the lectures. I bet some of them are really bad. It's a good few years ago now, but my lectures were truly appalling. I made the mistake of working really hard in the first year, quite hard in the second, then got disillusioned and worked barely at all in the final year. I discovered how to enjoy myself a little late! Not the best way around, but I have no regrets.

I see that you posted an article on Solitons. It read very well, although I might have to take issue with that '8 times around the M25'. That has the feel of an urban myth about it. If you think about how long that would take at said speed, we must be talking about almost 24 hours and I don't think even the M25 could support the required traffic density for that long. I'd pick your lecturer up on that one. Sorry to be pedantic.

Apart from being the many-who-is-one, you are becoming something of a portal too. I think there are a small number of people on h2g2, such as yourself, who function as the nucleii of clusters of forum activity. These clusters are probably reasonably discrete at the moment, but once the network of links becomes sufficiently dense there may well be some kind of phase shift to an even richer h2g2 experience. I say this because I got a wonderful argumentative posting to Mountains ( http://www.h2g2.com/forumframe.cgi?forum=31029&thread=35442 ) tonight, who had obviously come to me through you. I got to your Solitons article back through their forum postings. You'll have to drop by. Things could be hotting up.

Reality check: something I rarely remember to do...
Thanks, Serendipity

Wave-particle duality is confusing me in a way I never thought possible... its a particle, but that doesn't mean anything because it ain't a particle until it interacts with, for example, a detector... and get diffracted by about 1*10^-34 of a degree if I walk through a door... will this ever make sense?
I suppose not, if I continue to try to apply my macroscopic common sense to microscopic problems... but finding how to think in a microscopic way.... ugh.

I'm afraid you can't fight it. You can't reason with it. You can't apply any kind of logic to it. Tough eh?

That said, it may help to share some of my experience. Are you familiar with the double-slit experiment because, in a way, that encapsulates all the paradoxicality of the quantum world. If you are, I will leap in with a way of presenting a 'physical' picture; if not, I'll supply a little preamble first. Let me know.

I have done the double slit experiment... that was Monday's lecture, although we studied it a bit last year too

Good. This is not something that is going to be easy to describe, the difficulties compounded by my own incomplete understanding. And I definitely want to help rather than confuse, so give me a day or two to put this together properly.

I do enjoy these conversations where you can take your time and really deliberate over your response.

I think I'm beginning to understand this wave-particle thing more... I was confused by the idea of an electron interfering with itself... how can a particle interfere with itself or other particles? How does it know? ...but now I see that there's another way to think about it... not as an interferance pattern but merely as the probability function: if theres just that probability of an electron going through a slit and strinking somewhere, the same rules apply for the next electron... just like tossing a die...

You don't happen to have any interesting insights on the photoelectric effect, do you? I have to do a talk next week

Hi, you're getting the picture, but don't make the mistake (like everybody does) of giving physical reality to this 'probability wave'. I was aware yesterday that I've been deliberating far too long in replying with this alternative view of the double-slit experiment. It has been a case of that situation where you have an intuitive concept in your head, but when you try to rationalise it with words and logic, it steadily slips away.

What I wanted to describe was a picture of a particle inducing resonance patterns in spacetime as it moves, at a very high frequency, and this wave pattern, which shows interference bands as a result of the slits, acts as a carrier for the particle wave, which (rather aptly) you could look on as a soliton. It is difficult to grasp because it pictures a particle as a wave in space being carried
by a wave in space. Basically, the carrier wave acts as a guide, and represents something like an energy surface to the particle, so that the particle is more likely to follow certain paths, and less likely to follow others.

This is a version of the pilot wave theory which was first suggested by de Broglie and taken up by David Bohm. The mathematics does hold up, but it is not particularly fashionable because it is nothing like as elegant.

As for the photoelectric effect, I can't offer any special insight there. (Do I hear a sigh of relief?) There is an interesting historical footnote, though, for it was for his work on the Photoelectric effect that Einstein won his Nobel Prize, not for his work on Relativity.

Good luck with the talk.