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You might want to check out this URL. This is a Caltech professor talking about the lousy job market in physics. He goes into detail about what is going on. It is not a pretty picture. Unless you're very very good, physics is not something to base a careeer on. I wish it were different, and it will be someday, but not for quite a long while.

Goodstein's The Big Crunch

I dunno - whenever I read about "Retinal Painting Displays" I am reminded of the episode of

Star Trek (tm) The Next Generation (tm) "The Game"

It's bad enough people drive now while gabbing on a cell phone...

Isn't that special?

First off, I resent the patronizing tone of your post; there have been truly enormous flame wars started by less insulting comments than your own. With that in mind, I have temporally disabled my tact module.

This preprocessed information only goes directly to the old subcortical vision systems.

There seems to be some severe misunderstanding here. If information is processed by the retina, I fail to see where this unprocessed information you refer to would originate. Are you implying that there are two parallel circuits originating on the upper layers of the retina? If the information has been processed before it reaches the optic nerve (i.e., by the retina), how does this unprocessed information arrive at the cortex?

You imply that the visual cortex gets all or most of its input from the LGN. You have it completely wrong I'm afraid. There isn't any room for doubt about this...

Having just scanned through every neuroscience text I could my hands on, I'd say there is considerable room for doubt. Churchland, Crick and Koch (to begin with) all seem agree that the LGN has rich upward connections to the cortex in all mammals, while making little or no reference to any other pathways.

(BTW, have you considered how implausible your explanation is from an evolutionary standpoint?)

...an entirely separate issue from the conscious vision I was talking about in my previous post.

This is an immensely ironic statement. See my closing.

And, as we all know, these cortical pathways are the ones that make us intelligent, perceptive - and, dare I say it - conscious.

True, false and false, respectively.

(Snipping the lecture on the LGN....)

In other words, these bandwidth-limited ascending pathways represent a pretty trifling quantity of information passed on to the visual cortex from the LGN.

Oh, yes, that's the only possible explanation....

Well, what can I say? Cortex roolz! It's what makes us human.

*sigh*

Seriously, it's obvious that you're fairly well read but you have to careful not to identify too closely with certain researchers' narrow preoccupation's.

As opposed to you, who thoughtfully provided one reference to back his argument, and, ironically enough, a researcher who is 'preoccupied' spinal and cerebellar neurons.

As for the rest about the cortex, I would strongly suggest you read: Panksepp's Affective Neuroscience; virtually anything by Crick, Koch; Newman and Baars re. the ERTAS; Damasio as referenced by Calvin; anything by Doug Watt; or the papers here or at the ASSC's online conference about emotion before lecturing about the function of subcortical systems. (Good starting hints: your assessment interaction of emotion and sensory information is 180 degrees from the truth, and consciousness is not a cortical function.)

this page tells of Dr Arthur G. Lintgen being tested by James Randi, and Lintgen passing Randi's tests.

Here's a link to a Caltech Research group that is working with the UMass scientist who sent in the abstract to the xxx.lanl.gov site. This is the research group run by the phys prof I had last year for freshmen physics, all the work he does is on the Cosmic Microwave Backround Radiation (CMB). He showed us some very cool pictures that a BOOMERANG satellite had taken of the CMB. Consequently, this Slashdot article refers to information gleaned from another BOOMERANG run. More information than I can understand about this is here:
http://astro.caltech.edu/~lgg/boom/boo m.html

Hey, I have a sense of humor.

Down here in Louisiana, we like to pass a good time, so I'll let that remark slide. But we also like to work hard, whether it is on a backhoe (yeah, I've done that) or detecting gravity waves (I'm going to the dedication today, just down the road).

And as a proud citizen of Louisiana, I challenge your lamer ass to a game of Dune2000. Weenie.

Presumably a gravity wave will hit all the detectors at the same time, since gravity moves as fast as it wants to and doesnt have to be held back by the speed of light rule

Actually, gravity waves do travel at the speed of light, at least according to the theory of general relativity. Of course, this is subject to experimental verification, which is one of the reasons why these gravity wave detectors are being built.

What's really amazing about this project is the fact that they're going to be looking for an extraordinarily weak signal in a bunch of background noise. So how do they know that what they're looking at is the real thing? Well, that's one of the main reasons for having multiple detectors. With the sites in both Washington and Louisiana, they'll be able to look at coinicdences between the signals to determine if the event was a gravity wave or simply some local fluctations due to seismic activity or fluctuations in the laser or one of the other countless things that might give rise to a false signal. I used to be skeptical that these things would be able to detect anything at all (except noise), given that the amplitude of the waves they're trying to detect is smaller than the size of an atom! But I now know (due to a class that I'm taking that's being taught by Kip Thorne) that a lot of thought has been put into all of this and I'm fairly confident that we'll see gravitational waves with LIGO. For more information on the project, check out the Caltech LIGO website.

http://ligo.caltech.edu

Caltech's Press Release

I don't know why their writing articles on this now. LIGO has been in the works for quite a while now.

Just to give you an idea of how sensitive these things are: my roommate spent the summer working on calculating shifts in the earth's crust caused by the sun and moon, so that the correction factors can be applied. If I remember correctly, at one point Kip Thorne (the Feynman Professor of Physics here at Caltech) was working on correcting for the change in Earth's momentum caused by raindrops hitting the surface.

-ElJefe

http://ligo.caltech.edu

Caltech's Press Release

I don't know why their writing articles on this now. LIGO has been in the works for quite a while now.

Just to give you an idea of how sensitive these things are: my roommate spent the summer working on calculating shifts in the earth's crust caused by the sun and moon, so that the correction factors can be applied. If I remember correctly, at one point Kip Thorne (the Feynman Professor of Physics here at Caltech) was working on correcting for the change in Earth's momentum caused by raindrops hitting the surface.

-ElJefe

As far as I recall, general relativity defines gravity as the curvature of space-time. Gravity waves are the result of changes in the curvature of space time. Gravity waves are theorised have these properties:

Gravity waves will be accompanied by gravitons, a hypothetical particle that has zero rest mass and twice the spin of a photon.

Gravity waves and gravitons propagate outward at the speed of light.

Gravity waves compress mass in one direction perpendicular to the direction they travel, and expand it in a direction perpendicular to both the direction of compression and direction of travel.

Gravity waves are moving ripples in space-time.

Black holes coliding make big gravity waves.

Gravity waves pass through matter.

This experiment it is trying to get empirical evidence on all of the above claims. This has been a goal of some physicists since the theory was proposed in 1916. However, this goal has previously been beyond experimenters technological reach. It takes today's most sophisticated lasers and detectors to isolate a gravity wave from far away. Any local vibrations reaching either the lasers (like noise, or earthquakes) or the detectors will be easily confused with gravity waves. However, the mass of nearby objects does not interfere, just the vibrations they produce.

As for the design of the installation: it is in the shape of an L, because (as I mentioned before) gravity waves both compress and expand matter as they pass through it. On laser moves faster, and the other slower. This is different from a Michalson inferometer, which checks if normal gravity (that is: curvature of space-time) bends light. A Michalson inferometer isn't used to determine the nature of gravity waves.

Gravity affects all of the universe simultaneously (although it doesn't affect it much, it does affect it). Gravity waves are held back by the speed of light limit though. So, the two installations would get waves at different times, depending on the orientation of the earth to the event.

Of course, this is all conjecture, and that's why we US taxpayers get this installation. If this had already been proven, we wouldn't need these two new observatories.

PS: Check out the observatories homepage for more info!

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The benchmarking tools can be found here.

Http_load can be found here.

I used GNATS a few years ago on some Unix boxes for bug reporting and help desk-like work. It did the job better than the windows based help desk software that we paid for, but the unix folks found lacking (gotta love free software). At the time it had a Tcl/Tk gui interface, but it also apparently has a www interface too. Check out http://www.alumni.caltech.edu/~dank/gn ats.html for some GNATS resources. According to that page, the FSF, FreeBSD, and Apache projects use it.

Petabyte: 1,000,000,000,000 bytes

• 1 Petabyte: 100 printed collections of the entire US Library of Congress(!)

Now, I am substituting descriptions from different parts of his site. He actually compares a petabyte to 3 years of satelite data... but I can't visualize that very easily.

I can visualize the Library of Congress. The Library of Congress is a big place. Now, you want to stuff all that through a wire (or fiber... they had that in '89) 100 times in 30 seconds!! Incredible. I think someone had their exponents a little off.

This sounds like people I know who swear that government spy satelites can read your watch.

Oh, just one more thing, in the interests of accuracy. Just because I like base 10 instead of powers of 2, the numbers in my description may be off by, oh, say... 117,253 GIGAbytes . This minor inconvenience (errata, call it what you will) is brought to you by Microsoft, Intel, and the Windows calculator.

A petabyte, then a hexabyte...and some other things that haven't been settled yet. Check out Data Powers of Ten for more info, and a great comparison of scale.







-lx

Actually, it's "peta" which is then followed by "exa" and then "zetta" and finally "yotta". There is a short breakdown of the meanin of the names at "http://www.ccsf.caltech.edu/~roy /dataquan/ety.html" which tells where the names come from. There is a much larger listing of magnitudes at "http://www.mcs.csuhaywa rd.edu/~malek/Mathlinks/Billion.html".

erg... it seems like the ABA's capacity for poor idea is on an exponential increase. Go here, i'm sure people will get a kick out of this.. =)

If anyone's interested, Caltech, the home of Professor Zewail, the chem winner, has a press release up as well as video from a press conference from earlier today.


Of course, I'll have to insert a Go Caltech! here (so I hadn't even heard of the place when he did his research in the late 80's... I'm here now.)

If the silicon technology doesn't want to get any faster, just use a different technology. The HTMT project is seriously looking at doing this within a decade, though it will mean significant changes in system architecture.

the Motif standard and the X standard that came along afterwards.

To which "X standard" are you referring? Xdnd is being adopted by at least three tookits, as far as I know (JX, where I think it originated; GTK+, which implements it in 1.2; Qt implemented it either in a late 1.4 release or 2.0, as I remember), but I don't think it's an Official X Consortium^H^H^H^H^H^H^H^H^H^H^H^HOpen Group^H^H^H^H^H^H^H^H^H^HX.org standard, as far as I know. Has it been adopted by X.org?

Both teams are working on interoperability

I think GTK+ 1.2 also implements the Motif drag-and-drop protocol (which may explain why dropping from the Motif-based Netscape to the GTK+-based GMC worked); what are Troll Tech's and/or the KDE team's plans to implement the Motif DnD protocol?

http://alumnus.caltech.edu/~dank/rsi.htm

As those of you who have read some of my postings may have noticed, I am (or at least try to be) a devout Christian and pretty vocal about it. I am also in some sense a scientist, althought out of date and not professional. Is there a conflict? No. There is no conflict.

Amen!

For the Catholic (both from the Vatican and from others) view on science and religion, see http://www.cco.caltech.edu/~newma n/sci-faith.html. Contrary to popular belief, the Church is not full of Luddites.

--

hmmm... is it possible to make a dual 486? that might speed things up at the low end how about a group of 5 386 chips? what would a computer with a dual pentium setup cost?

At college we had a Sequent Symmetry that started with 8 386-16MHz processors and slowly migrated up to either 16 or 32 (I forget how many) 486-33MHz processors. It was the fastest machine on campus for _years_. Pity it had to be decomissioned because we couldn't get any more hard drives for it. Needless to say, it was _not_ cheap, but at least it did _not_ run anything from Redmond.

Even wierder, I think there used to be an architecture out there called a 'Hypercube' that was anywhere up to 256 '286 processors in parallel. That's right, 2^8 Intel 80286 CPU's. If I remember correctly, though, it had _no_ '287's and so it's floating point performance was still pretty sucky. Even so, I wish I could get my hands on one of these today. I'd put it right next to my NeXT.

In short, just about _any_ processor, no matter how weak, can be used in a powerful parallel system _if_ you are prepared to create an appropriate architecture and OS to support that many CPU's. The machine you come up with _could_ be relatively inexpensive to manufacture, but the development costs would enormous.

Stuff like SMP Linux and parallel computing standardizations have made parallel computers MUCH simpler and cheaper in recent history. But that's only if you use those standards etc., and I don't think you're going to find any older/cheaper architectures that follow the standards. Besides, the Dual Celeron board from Abit (the BP6) is _really_cool_ and _really_cheap_.

If you _really_ want to play with a cheap parallel system using older technology, don't think 'parallel computer'. Think 'cluster computer'. Think Beowulf. You won't be disappointed (and you won't have to take all those old processors out of their current cases).

Now, if Loki is offering something like a Beowulf cluster in return for 48 hours worth of hacking on their game, I might enter. Realistically, though, I would probably be more interested in their contest more if they offered the winner a job instead of the computer (at least a job better than the one I currently have).

It might be interesting to enter their contest for just the chance to look at their current game code, which I beleive is not open source. But that brings up an entirely different subject. Since the contestants have to be able to look at their current closed source, they will probably reqire the contestants to sign all sorts of 'Non-Disclosure - Non-Compete' forms. And trust me, NO computer or contest (or job for that matter) is worth all that.

Perhaps I should put the previous paragraph up as a post on its own.

• Precision. Beyond a certain point, bits get very expensive in analog, and analog operations add noise. If you need to chain more than a few operations, it wins to A/D convert and do them in digital-land.
• Power. It once looked like analog would have a big watt-per-bit advantage over digital, for low-precision stuff anyway. But digital VLSI just keeps getting better and better in this respect, and in some applications the analog advantage is no longer there.
• Stability. It is hard in practice to keep analog calibrated, and taking care of this adds circuit complexity that is not at first obvious. Digital circuits by comparison (not to put too fine a point on it) only need to worry about being off or saturated.

--Seen

Mont Blanc uses a liquid scintillator, which emits a flash when a neutrino event occurs. This approach has the advantage of providing immediate notification and good time resolution.

The detector with the coolest name is Super Kamiokande, in Japan. It was originally designed to detect proton decay by observing the Cerenkov radiation from the fast electrons that would be a decay product, but it also can detect neutrinos. It also provides immediate notification and good time resolution.

The most famous result from neutrino detectors is that the observations of the solar neutrino emission do not agree well with theoretical predictions.

In addition to the detection of solar neutrinos, neutrino detectors also scored big-time by detecting the neutrino burst of supernova 1987a. Because neutrinos pass through just about anything, these observations were useful probes of what was happening at the center of the SN.

Notes for a talk I gave in an undergrad class are available at http://wopr.caltech.edu/~mph/papers /neutrino.ps. References to other works are included.

The closest things that are available are Code Crusader and KDevelop.



There's several other options out there, but they're not as nice as these two, IMNSHO...



Both offer project management, class browsing C++, syntax highlighting, etc. KDevelop looks nearly like VisualC++, Code Crusader is more closely modeled after Code Warrior. These decisions dictate code choices.



KDevelop does class browsing in a way much like VisualC++ does. Code Crusader shows classes in a class inheritance tree.



Each of these environments have their own set of problems- you'll need to evaluate their offered functionalities and find out the drawbacks for your purposes and choose accordingly.

The closest things that are available are Code Crusader and KDevelop.

There's several other options out there, but they're not as nice as these two, IMNSHO...

Both offer project management, class browsing C++, syntax highlighting, etc. KDevelop looks nearly like VisualC++, Code Crusader is more closely modeled after Code Warrior. These decisions dictate code choices.

KDevelop does class browsing in a way much like VisualC++ does. Code Crusader shows classes in a class inheritance tree.

Each of these environments have their own set of problems- you'll need to evaluate their offered functionalities and find out the drawbacks for your purposes and choose accordingly.

Code Crusader (http://www.cco.caltech.edu/~jafl/jcc/)

also go here halfway down the page
jump to "turcotte"

If you are using one of the 2.0.XX series of kernels, get the loose-udp patch from this page. It makes a big difference in performance of multiplayer games and the extra auto port forwarding is unneccessary.

Andrew