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A positive use for Tasmanian's. Explanation for non Australians found here http://www.utas.edu.au/library/companion_to_tasmanian_history/T/Tas%20reputation.htm

Homo sapiens has had more impact on biodiversity than any other species. The Great Oxidation Event lasted hundreds of millions of years and, while we have no means of establishing a survey of taxa from that era, it was most likely the result of a very large number of species, and indeed is such a long period of time that many speciation events could readily have occurred. Further, the autotrophs that released the oxygen in the first place had no means of affecting many of the anaerobes that live deep underground—and we do.

Here are your citations for humanity's impact. Suffice it to say that many of them will still be noticeable in a few million years:

• Climate Change, Human Impacts, and the Resilience of Coral Reefs
• Consequences of changing biodiversity
• A continent transformed: Human impact on the natural vegetation of Australia, which went on for something like sixty million years before we screwed it up.
• Tropical forest recovery: legacies of human impact and natural disturbances
• The Future of Biodiversity, the abstract for which starts: "Recent extinction rates are 100 to 1000 times their pre-human levels in well-known, but taxonomically diverse groups from widely different environments. If all species currently deemed "threatened" become extinct in the next century, then future extinction rates will be 10 times recent rates. Some threatened species will survive the century, but many species not now threatened will succumb. Regions rich in species found only within them (endemics) dominate the global patterns of extinction."
• Urbanization, Biodiversity, and Conservation
• Biodiversity inventories, indicator taxa and effects of habitat modification in tropical forest (PDF)

I don't know why you then decided to compare humanity's effect on biodiversity to that of mass extinction events, but let me explain to you why they are completely different.

When an extinction event occurs, there is a single source of pressure that living organisms must accommodate, or at most a couple: the sky is darker, the air is colder, the atmosphere is now filled with water rather than ammonia, et cetera. Humans have not been exerting this kind of pressure at all. We systematically destroy ecosystems, replacing hundreds of species of plants and animals with just one or two (which are, naturally, attuned to depend on us feeding, fertilizing, irrigating, and sheltering them) and we poison the water, air and soil with thousands of chemicals and chemical cocktails (an issue which is now so bad it's affecting us.)

This is too much for evolution to handle. Especially due to chemical poisoning, many of the hardiest species most likely to survive a natural disaster have been snared by exotic and unexpected genetic vulnerabilities. DDT was found to act as a sex hormone in birds, for example, causing males to develop female genitalia. As a South African, I'm sure you're aware that it's still in use, combating Malaria, even though it has been banned in many countries.

We are whittling down biodiversity in ways that the Great Oxygen Catastrophe didn't. It selected one major branch of the tree, the organisms that depended on a reducing atmosphere, and marginalized them, creating room for the healthy and d

This is something that I have had an interest in for the last few years. As such, a large part of my thesis has been developing "CompTorrent". It is a computing platform that has borrowed some ideas from BitTorrent and combined them with distributed computing.

The focus has been on making distributed computing projects as easy to start as a BitTorrent swarm. After spending some quality time with both BOINC and Condor I can assure you that getting a project going from scratch, can be a non-trivial exercise.

Here's a paper if anyone is interested: Enabling grassroots distributed computing with CompTorrent

Straight space as observed by human eyes and interpreted by human brains is defined by movement along a light ray path. It is obvious because if you are looking directly at an object as it appears that is where the photons come from.

Light bends severely near the event horizion making it an invisibility cloak even better than this one: http://science.howstuffworks.com/invisibility-cloak.htm because instead of mimicking the light it actually bends space to redirect the light itself. Sweet...

There is a point at which any object directly behind the black hole makes a ring due to space being bent like a lens so that the rays converge and fall on a single point. However lensing by a black hole, even up close, will resemble this http://www-ra.phys.utas.edu.au/~jlovell/simlens/lens_large.gif

Ever since Disney's movie http://en.wikipedia.org/wiki/The_Black_Hole (damn that cover) everyone runs around thinking about how wide dem' black holes are.

If you could see past all the super heated hydrogen (as in the artistic rendering) black holes have zero angular width because light (and anything else) only passes through the essentially spherical event horizion at near 90 degrees. This condition is satisfied by a point in our visible space. It is not possible to view one directly at all. This instead has the effect of bending space such that the background behind the black hole is distorted.

http://en.wikipedia.org/wiki/Gravitational_singularity

While in a non-rotating black hole the singularity occurs at a single point in the model coordinates, called a "point singularity," in a rotating black hole, also known as a Kerr black hole, the singularity occurs on a ring (a circular line), defined as a "ring singularity."

Yet on this page http://en.wikipedia.org/wiki/Black_hole#_note-0 here comes the giant black ball of timely death.

INAP but it stands to reason that light rays simply do not terminate without a far end in our space time. There may be a dim spot near the center of the lens - but no black. Looks like this is a little more accurate simulation: http://en.wikipedia.org/wiki/Image:BlackHole_Lensing_2.gif

Here is a more accurate animation showing how the famous 'ring with a black center' looks in motion. http://www-ra.phys.utas.edu.au/~jlovell/simlens/lens_large.gif The hole would just appear black because the light rays that would come from the center are higly bent and therefore are dim in the same way that light viewed through a microscope is dim.

How much more must we endure before the artists talk to the scientists?

Ever since Disney's movie http://en.wikipedia.org/wiki/The_Black_Hole/ (damn that cover) everyone runs around thinking about how wide dem' black holes are.

If you could see past all the super heated hydrogen (as in the artistic rendering) black holes have zero angular width because light (and anything else) only passes through the essentially spherical event horizion at near 90 degrees. This condition is satisfied by a point in space. It is not possible to view one directly This instead has the effect of bending space such that the background behind the black hole is distorted. http://en.wikipedia.org/wiki/Gravitational_singularity/

Yet on this page http://en.wikipedia.org/wiki/Black_hole#_note-0/ here comes the giant black ball of timely death.

INAP but it stands to reason that light rays simply do not terminate without a far end in our space time. There may be a dim spot near the center of the lens - but no black. Looks like this is a more accurate simulation: http://en.wikipedia.org/wiki/Image:BlackHole_Lensing_2.gif

Here is an accurate animation showing how the famous 'ring with a black center' looks in motion. http://www-ra.phys.utas.edu.au/~jlovell/simlens/lens_large.gif/

How much more must we endure before the artists talk to the scientists?

I totally agree with you.

I see the difficulty of starting a distributed computing project as being a serious problem.

One solution I am proposing is borrowing some of the techniques from BitTorrent and using them in distributed computing. So far, the results have been very encouraging.

So here is a tidbit of my PhD research (an abstract from a paper hopefully being published soon):

"This paper describes the operational characteristics of "CompTorrent", a general purpose distributed computing platform that provides a low entry cost to creating new distributed computing projects. An algorithm is embedded into a metadata file along with data set details which are then published on the Internet. Potential nodes discover and download metadata files for projects they wish to participate in, extract the algorithm and data set descriptors, and join other participants in maintaining a swarm. This swarm then cooperatively shares the raw data set in pieces between nodes and applies the algorithm to produce a computed data set. This computed data set is also shared and distributed amongst participating nodes. CompTorrent allows a "simple home-brewed" solution for small or individual distributed computing projects. Testing and experimentation have shown CompTorrent to be an effective system that provides similar benefits for distributed computing to those BitTorrent provides for large file distribution."

If anyone else is interested in my shameless self promotion: http://www.comp.utas.edu.au/users/bcg/

A 100 metre race has been arranged between Achilles and the tortoise. Of course Achilles can run much faster than the tortoise, so Achilles feels pretty confident of an easy victory. He therefore decides to make the race a little more interesting by giving the tortoise a 10 metre head start. Most of the spectators are sure that Achilles can easily make up the 10 metre deficit and they place bets on Achilles to win. The wise old Zeno, however, decides to bet on the tortoise. Zeno reasons as follows: The first thing Achilles must do is to run to the tortoise's starting position. But while Achilles is doing that, the tortoise, although slow, will move on to a new position. Next, Achilles must run to the tortoise's new position, but once again, while Achilles is doing that, the tortoise will move on a little further and so on and so on. No matter how small the gap between them is, while Achilles is closing the gap the tortoise is able to make a new gap. Zeno concludes that no matter how fast Achilles runs, he can never catch, let alone pass, the tortoise. Since Achilles can't pass the tortoise, so long as the tortoise keeps moving, the tortoise will win the race. What do think about Zeno's reasoning?

Say Achilles runs at 10 m/s. The turtle at 1 m/s. The distance at which Achilles will catch the turtle is X. Say that one second passes, then The turtle will be at 10 + 1 = 11 metres. And Achilles will be at 0 + 10 = 10 metres. Then one tenth of a second passes. The turtle is now at 11 + 0.1 = 11.1 metres. Achilles, therefore will be at 11 metres.

X = 10 + 1 + 0.1 + 0.01 + 0.001 + 0.0001 ... Eq. "1"

X = 10 + (1/10)*(10 + 1 + 0.1 + 0.01 + 0.001 + 0.0001 ...) Eq. "2"

X = 10 + (1/10)*X

X = 10/(1-(1/10)) = 10/0.9 = 11.1111(...)

awesome. it matches eleventyone!

But not Eleventeen, sadly.

According to this, b15 was 200 to 350 metres thick at calving time.
It was estimated to be 70% of the annual 2500 giga-tonne ice output from the Ross shelf. That's 1750000 million tonnes!
(note that a metric tonne is spelled differently than an imperial ton.)

First off, IANAQP. Most of my modern cosmology and quantum physics comes from SciAm, Brian Greene books, and conversations with Tripoli Rocketry Association member #004. The last time I did tensor calculus was when I looked up Frank Tipler's paper "Rotating Cylinders and the Possibility of Global Causality Violation" twenty years ago. Yes, that is the paper Larry Niven used as the name for a story.

So, based on my rather crude understanding of the whole mess, the answer to your question is "yes." We don't see the extra dimensions in our universe because they are curled up and small. If you look out your window at a telephone wire, the wire appears to be 1 dimensional - it only has length. A closer look shows that the second dimension is "wrapped" around and meets itself.

These dimensions are thought to be exceedingly small, although some string theories allow for the possibility that they could be as big as a millimeter in diameter. The last experiment I remember reading about indicated that, while a millimeter might be too big, they couldn't rule out dimensions on the order of .1 mm. If one of the dimensions is that large, we should soon be able to measure the failure of the inverse square law at very small distances, where gravity leaking into the other dimensions can be seen.

If the four macroscopic dimensions (3 spatial, one time) form closed loops, we might indeed have a strange geometry in space, such as a "horn of plenty."

It's comforting to think that the 4 large dimensions curl up like the small ones. The universe can be "infinite but bounded." There's no messy questions about what happens when you reach the edge of the universe or the universe being infinite in size, although I'd still wonder what's "outside" our universe. There's a symmetry - the big dimensions are simply blown up versions of the small ones and (in some ways) the big dimensions might actually be the same size as the small ones! Measuring the diameter of a dimension can be tricky, since in string theory large and small dimensions are indistinguishable mathematically.

Alas, there's no guarantee that the 4 macroscopic dimensions have their "ends" meet. String theory can handle infinite dimensions and non-loop strings with end points as well. If you could travel far, far faster than light, you might simply keep going in one direction, never returning to your point of origin.

We may never know the answer. If the universe is far bigger than the 156 billion lyrs minimum, then we'll never see edge effects on the cosmic microwave background. The macroscopic universe might go on forever or loop back around or come to a dead stop at a giant brick wall - and we'll never know.

There are two major problems with current quantum cosmologies. One is that they're exceedingly and increasingly difficult to calculate. What good is an equation that is the "answer to everything" if there's no possible way to solve it or even come up with a decent approximation to an answer? The other problem is that there are probably an infinite number of possible theories, and even if they can be solved, the vast majority predict the same answer at any level we could ever hope to explore in any conceivable experiment.

Think of it as job security for physicists.

I wish I could find a link to George Carlin's riff on the Catholic Church's answer "It's a mystery!" It would be oddly appropriate.

I am a post graduate student who is researching aspects of P2P software. Its a really fertile area for research that is now starting to get seriously damaged by the civil and criminal suits that are getting about these days. I know of one serious research group that has pulled their software, that wasn't even file sharing related, due to fears of being held accounatble for its use. I also have not released anything due to fears of retribution (and my stuff has bugger all to do with filesharing also).

I would like to extend my Masters research into a PhD but is it going to have a future for long enough? I hope that this will settle down and go the way of the fears of video tapes, PGP, cd burning, etc... But in the mean time research that will benefit ad hoc networking will suffer.

It will be a sad day if everything P2P is banned - I wonder if those companies with miss chat, dns, nntp, etc

A Cup of Tea

Nan-in, a Japanese master during the Meji era (1868 - 1912), received a university professor who came to inquire about Zen.

Nan-in served tea. He poured his visitor's cup full, and then kept on pouring.

The professor watched the overflow until he no longer could restrain himself. "It is overfull. No more will go in!"

Like this cup", Nan-in said, "you are full of your own opinions and speculations. How can I show you Zen unless you first empty your cup?"

Well, at the least you could install wtf. Granted you need to successfully get a linux or bsd installed first.

A google search for "hilary clinton" "spy magazine" dominatrix turned up this page which has the photo (unfortunately a poor copy) and a discussion of how it was done.

The page goes on to say:

This issue of Spy sold more copies than any other in the magazine's history.

John Daly is hardly a skeptic. He uncritically accepts evidence that supports his claims, and ignores anything that contradicts it.

An example, he uses the Island of Tuvula as an example. He shows some raw data, but ignores an inconveint analysis of it (which can be found here) which finds that the sea levels around Tuvula are rising (abit with a large uncertainity in the data) at a rate which is line with the IPCC estimates.

Having read a lot of John Daly's evidence I think global warming falls into the same category, trendy pseudo-science.

Whereas I (having read some of John Daly's "evidence", plus a whole lot more peer reviewed scientific articles of global warming) think that global warming is a well respected scientific theory who's critics have lost the science battle along time ago, and have hence shifted the debate into a propaganda war.

Here's a short analysis of it. Basically, it seems you resolve the paradox by making up a new word and using that to explain it.

As O'Reilly states, WinSock is more a specification, a set of APIs. Anyone could write an implementation. Several did. It just so happens that Peter Tattam wrote the best for Windows 3.1. Also he wrote a scriptable dialer which back in those days was what a lot of people needed to negotiate the hodgepodge of dial-in methods required by the much less consolidated ISP industry. And Tattam gave his package away as shareware so it could spread very fast.

It gets better though from the perspective of an argument against bundling. There were quite frequent warnings as you can see in the alt.winsock FAQ about having the "right" WINSOCK.DLL installed with all others removed. And with the change to Windows 95, I can remember the huge amount of hype over whether one should go "32-bit". Here's a sample from back then which includes advice to simply remove Trumpet Winsock under certain circumstances.

Unfortunately for the opponents of bundling, the problem with this otherwise perfect example is that it is inconceivable that a modern consumer OS would lack either a TCP/IP stack or a dialer. Trumpet Software had the clear market leader. Microsoft in Windows 95 bundled both its own TCP/IP stack and a dialer DUN. This bundling introduced potential incompatibilities that even led for some to advise uninstalling Trumpet's product. So should the government have had the right to force Microsoft to stop invading this software niche? Should it have mattered that Tattam wasn't the head of a much larger company such as Netscape? Should it have mattered that Tattam wasn't American?

By the way, Trumpet Software is currently developing a new 32 bit OS PETROS.

A friend of mine has details on Intel CPU prices going back as far as 1994 in some cases - check out the details on his site.

There are extant species which have no genetic variation - the entire population is a clone. If you'd prefer a mamalian example, the limited gneteic variation of the Cheetah is well known - but people often forget that until recently it was very successful with a huge range across Africa and Asia - one of the most widespead of all mammals. Andrew Taylor

Here's an example all.js that helped me some.

My first web experience was using the Cello browser, written by Cornell university in order to expand its gopher law offerings to the vastly superior hypertext.

This was only shortly after finding my first somewhat graphical ftp client.

I was working at a help desk in those days, and managed to convince my boss to let me play around with the internet in my spare time. I had a modem already, and a Unix shell account with access to newsgroups and mailing lists, but actually making a Windows PC talk to the internet was an incredibly wondrous thing [heh, still can be some days]. There wasn't even Trumpet Winsock in those days, nor a Novell-supplied winsock client -- I had to download two or three separate drivers, one of which had to be loaded into the Netware ODI client, and eventually it was all working. (Somebody else had a similar experience.)

Those were heady days.

I think I used Cello until Netscape came out.
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You: Have you got a URL that shows this?

Oops, allow me to insert foot into mouth here. I meant background images, honestly I did.

They claim to support background-images (per your link above). My example link (though the college page has them too) is http://css.tuu.utas.edu.au/~brong/opera.

As a side note: when you select white text on a white background in Opera, it doesn't separate the colours, so you still can't tell what it says without looking at the source. In IE it became aqua on white.

Little annoying things, but they make it hard to use at times.

You could pronounce this as "So web designers will be able to produce standards-complient pages that work with anything.

When we built our College's web page earlier this year, we decided to go all out with style sheets and reduce the style markup in the HTML as much as possible. While IE rendered it reasonably well (with some irritating margin bugs which forced us back to tables anyway), Netscape made a horrid mess of it.

What we have now is a massive compromise with tables everywhere just to make things hold still as the page gets resized.

Every web designer who actually writes their own code rather than using the output of some braindead bloatware (use view source more often to be horrified) has been waiting for Mozilla just so that they can have a reference base to see how their page is supposed to look, before back-compatability cludging it.

If only Netscape/Mozilla had picked up the standards clue earlier!