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[Being o]verweight is a serious health concern for children and adolescents. Data from two NHANES surveys (1976-1980 and 2003-2004) show that the prevalence of [being] overweight is increasing: for children aged 2-5 years, prevalence increased from 5.0% to 13.9%; for those aged 6-11 years, prevalence increased from 6.5% to 18.8%; and for those aged 12-19 years, prevalence increased from 5.0% to 17.4%.

I don't know about what your nutritionist friend considers a problem, but an almost 200% increase in obesity rates in a population over the course of three decades to comprise 14-19% of children seems like a major problem to me. But, maybe she is looking at it in comparison to adult obesity rates - which makes it seem like the kids are doing a good job keeping their weight down.

During the past 20 years there has been a dramatic increase in obesity in the United States. In 1985 only a few states were participating in the CDC's Behavioral Risk Factor Surveillance System (BRFSS) and providing obesity data. In 1991, four states had obesity prevalence rates of 15-19 percent and no states had rates at or above 20 percent....In 2005, only 4 states had obesity prevalence rates less than 20 percent, while 17 states had prevalence rates equal to or greater than 25 percent, with 3 of those having prevalences equal to or greater than 30 percent (Louisiana, Mississippi, and West Virginia).

Sure, there are ways to manage weight, like the Hacker's Diet, but it is also clear that people aren't doing it in the U.S.

Metabolism is a crazy thing though. There is no one single rule that everyone can follow.

One the camera's four color detectors has completely stopped working, and it is feared that the problems are spreading.

Actually, you can travel a light year in significantly less than a year, depending on how one defines "light year" and "year". For example, if you accelerated at 1 g towards Alpha Centauri (fun fact: 1 g is just over 1 ly/yr^2!), you would reach Alpha Centauri in about 2.25 years. Of course, looking back the original distance of 4 light years would now be shortened (thanks to that fella Lorentz). Bonus fact: as you pass Alpha Centauri, you will be covering 5 light years (as measured in the Earth frame of reference) per year (as measured in your own frame of reference)!

See, Einstein wasn't so mean after all.

What we do, then, is measure a pair of these intervals, and emit a zero or one bit based on the relative length of the two intervals. If we measure the same interval for the two decays, we discard the measurement and try again, to avoid the risk of inducing bias due to the resolution of our clock.

You can find more at Wikipedia's article on hardware random number generators:

There are two fundamental sources of practical quantum mechanical physical randomness: quantum mechanics at the atomic or sub-atomic level and thermal noise (some of which is quantum mechanical in origin). Quantum mechanics predicts that certain physical phenomena, such as the nuclear decay of atoms, are fundamentally random and cannot, in principle, be predicted. (For a discussion of empirical verification of quantum unpredictability, see Bell test experiments.) And, because we live at a finite, non-zero temperature, every system has some random variation in its state; for instance, molecules of air are constantly bouncing off each other in a random way. (See statistical mechanics.) This randomness is a quantum phenomenon as well. (See phonon.)

Because the outcome of quantum-mechanical events cannot in principle be predicted, they are the 'gold standard' for random number generation. Some quantum phenomena used for random number generation include:

• Shot noise, a quantum mechanical noise source in electronic circuits. A simple example is a lamp shining on a photodiode. Due to the uncertainty principle, arriving photons create noise in the circuit. Collecting the noise for use poses some problems, but this is an especially simple random noise source.

• A nuclear decay radiation source (as, for instance, from some kinds of commercial smoke detectors), detected by a Geiger counter attached to a PC.

• Photons travelling through a semi-transparent mirror, as in the commercial product, Quantis from id Quantique SA. The mutually exclusive events (reflection -- transmission) are detected and associated to "0" or "1" bit values respectively.

Thermal phenomena are easier to detect. They are (somewhat) vulnerable to attack by lowering the temperature of the system, though most systems will stop operating at temperatures (e.g., ~150 K) low enough to reduce noise by a factor of two. Some of the thermal phenomena used include:

• thermal noise from a resistor, amplified to provide a random voltage source.

• Avalanche noise generated from an avalanche diode, or Zener breakdown noise from a reverse-biased zener diode.

Autodesk was a market leader and a real Silicon Valley 80s-90s wonder. One of the great things that came out of it, indirectly, was the book "The Hacker and the Ants" by Rudy Rucker which had some obvious inspiration from the time Rucker spent at Autodesk. The CEO at that time John Walker is a remarkable guy. As a bunch of people have already pointed out, they are long past market relevance (except for legacy lockin issues) so this is sad, but they were at one time quite the acme of geekdom.

The Open Design Alliance understands that Autodesk has, for approximately two years, been distributing application programs which include our copyrighted DGNdirect libraries, for reading and writing DGN V8 format files. Autodesk does not have, nor has it ever had, any license or right to use DGNdirect in its application programs. We believe that Autodesk, by its actions, is infringing our copyright.

And I thought I sucked at math when I couldn't remember how eigenvectors work the other day...

The numerical solution of differential equations, notably the Navier-Stokes equations was an important stimulus to computing, with Lewis Fry Richardson's numerical approach to solving differential equations. To this day, some of the most powerful computer systems of the Earth are used for weather forecasts.

• John Walker
  
• Ross Anderson
  
• FSF
  

Assuming that this is the same guy, here's what John Walker (one of the founders of AutoDesk (AutoCAD, AutoLisp, 3DStudio, etc.)) had to say about his run-in with G. Pascal Zachary as a reporter for the Wall Street Journal:

Reporter at Work

Over time, this equality among Internet users has eroded, in large part due to technical workarounds to cope with the limited 32-bit address space of the present day Internet... With the advent of broadband DSL and cable television Internet connections, a segmentation of the Internet community is coming into being...

The typical home user never notices NAT; it just works. But that user is no longer a peer of all other Internet users as the original architecture of the network intended. In particular, the home user behind a NAT box has been relegated to the role of a consumer of Internet services. Such a user cannot create a Web site on their broadband connection, since the NAT box will not permit inbound connections from external sites. Nor can the user set up true peer to peer connections with other users behind NAT boxes, as there's an insuperable chicken and egg problem creating a bidirectional connection between them.

Sites with persistent, unrestricted Internet connections now constitute a privileged class, able to use the Internet in ways a consumer site cannot. They can set up servers, create new kinds of Internet services, establish peer to peer connections with other sites--employ the Internet in all of the ways it was originally intended to be used. We might term these sites "publishers" or "broadcasters", with the NATted/firewalled home users their consumers or audience.

I agree, there are a certain set of behaviors that are appropriate, especially for a work enviornment. However, at a workplace you are being paid, and the types of social control tends to be apolitical.

But political correctness is far beyond that. For example, things that the Seattle Public School system considers "racist" and are grounds for disipline, directly quoted from their speech codes:

"having a future time orientation, emphasizing individualism as opposed to a more collective ideology, defining one form of English as standard".

So in the Seattle Public Schools, correcting a student's grammer, disiplining them for being late, or critisizing socialism, could get you fired for being "racist". Do you think those things are racist?

Now, do you understand why people are so dead set against political correctness and speech codes? Do you think this policy is even remotely sane?

Here is the actual policy page I am quoting from:
http://www.fourmilab.ch/fourmilog/archives/seattle _schools_racism_2006-05-29/searace.htm

And while we're talking about geeks and Obesity, let's not forget The Hacker's Diet. In my experience, it's a sensible and effective way for people with a sedantary lifestyle to lose weight safely, effectively and sensibily. Some comments in this related Slashdot article are helpful too.

Let's not forget that microprocessors aren't capable of generating true randomness. An external source of entropy is required, such as a Lava Lamp, decaying Cesium-137 atoms, or something else..

Now, I gotta say it would be pretty cool if these iPods use a vibration-sensing mechanism to gather enough entropy to seed the PRNG!

--Weasel

Bill Gates was thinking about this in 1992.

Why the concern about miniature black holes? Every single day, perfectly ordinary cosmic rays impact the Earth's atmosphere with more energy than the LHC could ever hope to achieve. If modern accelerators can create miniature black holes (and there's a good chance they can), then so can cosmic rays.

The LHC is specced to accelerate protons to 7 TeV, and they'll be colliding two proton beams head-on for a total of 14 TeV (1.4×10^13 eV). In comparison, Oh My God! particles are in the vicinity of 10^20 eV (10 million times LHC), and even cosmic rays of 10^16 eV (1 thousand times LHC) are a fairly ordinary occurence. And if you're thinking that the LHC is creating a type of collision that doesn't happen in nature, most cosmic rays are themselves protons or nuclei, which then collide with air nuclei to produce particle showers, the exact same thing the LHC is doing. The collisions are proton-proton in both LHC and nature, so there's no good reason why the LHC would produce black holes but strong cosmic rays wouldn't.

What's more, there's no justification for fearing short-lived microscopic black holes. Black holes aren't cosmic vacuum cleaners; they don't magically pull things in. Things fall in because of gravity -- i.e. because the black hole is heavy -- and a microscopic black hole doesn't have a strong gravitational field, because it just doesn't weigh that much. That means that a microscopic black hole can only grow because things randomly wander into it -- and keep in mind that it's far, far smaller than an atom. Instead, Earth would pull the black hole into it!

Now, assuming that by some miracle the particle physicists were exactly right about the existence and behavior of protons yet exactly wrong about Hawking radiation, a miniature black hole granted such immortality would fall right through the Earth, whoosh past the center, zip through the other side, then proceed to orbit within the Earth in a similar fashion for the next 10,000 years, gradually nibbling away at the occasional nucleus that happened to be in the way. Eventually it would grow in mass enough that it would settle within the solid iron core of the planet, where it would eventually eat enough to destabilize the core, causing massive earthquakes and very slowly devouring the Earth from within, ultimately resulting in a black hole smaller than a marble (9 mm, roughly 0.2 in), possibly surrounded by an asteroid-size chunk of solid rock that could support its own weight with a hollow core.

Frankly, though, I'm more worried about George W. Bush gaining highly improbable mutant powers, flying into space to save the Space Shuttle, inadvertently merging with the Dark Phoenix, and scheming to destroy the world. It's about as likely, i.e. no chance in hell, and worrying about it occupies the same amount of time, i.e. zero seconds lifetime total.

For example, a single particle with an energy around 51 joules. That's 3E20 electron volts and it must have turned the nucleus it hit into something that only Doc Smith could describe. On the scale of that event the energies we produce in accelerators are, to a very good approximation, zero.

For example, there are as yet little-understood phenomena that can accelerate particles six orders of magnitude faster than anything achievable in a lab. Try reading about Ultra-high-energy cosmic rays.

More specifically read the story of the Oh-My-God Particle. This was a proton detected in October of 1991 that had an energy of 3.2 * 10^20 eV. The equivalent energy of a baseball thrown at 55 mph... all in a single proton travelling at 99.99999999999999999999951% the speed of light!

While something travelling that fast has little probability of interacting with anything you could imagine the surprise if one of those hit you! I think that the fact we are alive with such powerful forces already at work in our universe means we have little to fear.

yes

Certificate Revocation List, anyone? Read John Walker's Digital Imprimatur--it shows exactly how Digital Restrictions Management infrastructure such as that being built by Microsoft can be used to inhibit freedom of speech. Opposition to DRM isn't just about music and movies, despite what corporations and governments would like us to think.

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John Walker, of Autodesk fame, did a similar project, although with a simpler count-the-clicks approach. I copied it using an off-the-shelf Geiger counter and a piece of Autunite; it works well.

Well, it's refreshing to have a debate with real arguments, for a change, thanks... Even though I suspect we already agree on quite a few points. :-)

the "we should do it anyway" attitude comes down to convincing the government to increase the budget, which is separate from the best way of using it."

Well, yes, but note that you already use a premise about what 'the best way of using it' is.

I assumed that "the best way" was to make the most of a given budget, to do as much of "the stated goal" as possible. Then I tried to show that, whether this stated goal was space science or space colonization, you had to focus the effort you choose to spend on manned spaceflight on making it as economical as possible. Otherwise, for science, you end up doing less than what you could have done without humans on-site; and for colonization, you don't get a long-term commitment. Perhaps "self-sustaining" would be a better term than "economical".

Afterwards, differences in actions and decisions, as you say, stem from different estimations of how much and how fast the relative cost per capabilities of robots in space and humans in space will evolve. That's where you state that "if technology gets cheaper, it gets cheaper for robotic missions too", but it is not necessarily true. If launchers get cheaper, they do indeed for both ships and probes, but the cost of building and testing the probe becomes proportionately higher. If robotic technology becomes better and cheaper faster than launchers do, then you have a point. To be sure, I agree that robots are getting better and cheaper and will continue to do so, but some argue that we already have good enough technology right now, that the high launch costs are only a matter of flight rates. See for example A rocket a day. If that's true, then I see no point in funding NASA's missions as they are.

And even if robots remain forever a better science/cost proposition than humans, then it does not mean that one should send only robots into space; merely that science must not be the main justification for such a mission. Exploration and colonization should be. If you say you're doing it "for the science", scientists will argue that you'd do more of it with robots--as is now often heard. But then, you're absolutely right: if you do send a manned mission somewhere, just for the sake of it, you can probably include a scientist and instrument packages and do science as well. Not if it complicates said mission so much that it hampers the primary objective, mind you (no point in sending a dead scientist to Mars), but then it's "easier to train a scientist to pilot the spacecraft than to make a scientist out of a test-pilot astronaut"...

The extra costs of getting (and maintaining) a human in space is largely lacking on a base of Antartica. You have an breathable atmosphere, you have necessary resources (like water) in aboundance, you have normal gravity, you have the atmospheric shielding of our atmosphere, you don't have a need for a closed ecological system, food and supplies can be furnished regulary and relatively easily, etc.

It's not that different from e.g. Mars: there is water and carbon available there, gravity is over one third of Earth's (enough? Nobody knows one way or the other), enough atmosphere for meteorite and probably radiation shielding. And neither in Antarctica can you just step outside unprotected, nor get resupplied during the winter barring absolute emergency. Was it last year that there was the first medical evacuation ever in polar winter?

given the whims, if Nasa cuts their costs in half, it is not beyond possibility that politicians may decide to cut the budget in half because 'Nasa has shown it can do wha

My first thought was "oh my $DEITY, they *ACTUALLY* found it". But thun again, of course I've been reading too much sci-fi. It's just that this one story ....... well, here it is:

"We'll Return, After This Message" by John Walker, December 1st, 1989
http://www.fourmilab.ch/documents/sftriple/gpic.ht ml

It certainly isn't as easy as it looks but it's certainly cheaper (and hence easier in this case) than it costs. The Nazis under Hitler were producing V2 rockets at the rate of about 800/month which cost orders of magnitude lower [about $13,000 / rocket after the first 5000 according to the article linked below] than current rockets back in the 1940s and which could reach low Earth orbit. Modern rockets are definitely better equipped, but still the costs for unmanned rocketry can be brought down a LOT if more launches were made and the error margin was allowed to be lowered a bit.

(Granted, this commentry is about launchers that put payload in low Earth orbits, and the Indian rocket was likely one which put payload in a GTO. The point still is valid.)

John Walker has a good article about this.

Erm, you still have to get the fuel up there right? .. and the cost of putting something up there is still reasonably proportional to weight?

True, it doesn't save money in the short run. But even if all that fuel still comes from Earth, it lowers the minimum mass per launch. So you can use many light boosters to supply the fuel depot instead of a few heavy ones. Some people believe that the current high cost of launches is due to a low launch rate (maybe only 10-20 a year, worldwide), and increasing that rate would help lower this cost. See e.g. a rocket a day.

Exactly my dieting concept - lost me about 40 pounds last year by the same method. A nice overview on the topic can be found here.

So far, my diet is going great. But I had to do something about my Coke intake, and fast.

Diet Coke was what I used for comparison. Terrible... the artificial sweeteners have a metallic taste, so I feel like I'm drinking the T-1000. A little more shopping around, okay.

As for diet sodas, I found that Diet A&W has no detectible (at least, to my palette) artifice in its sweetness. It also has plenty of taste to it. That's my #1 choice for fizzy drinks now. Diet Barq's is close. Both of those are caffiene-free. I'm not sure if you'd consider that a boon or a bane.

If I gotta have the caffiene, Diet Dr. Pepper is the next in line. It comes in both caffienated and non- varieties, and the aftertaste is quite minimal. I noticed it for a week or two, but not anymore.

Unfortunately, some places (such as Subway, a dieter's haven for fast food) have exclusive contracts with Coca-Cola. The only diet drink my local Subway stocked was Diet Coke, ick. I wrote a letter to the manager complementing her store (if you're in Sunnyvale or Mountain View, the best Subway in the area is on El Camino, about a block south of Castro). I also asked if they would consider stocking some alternatives. Coca-Cola produces Minute Maid Light, another good alternative, even if it doesn't qualify as fizzy. They don't produce it in a bottle, though, but Coke Zero seems much more palitable than Diet Coke. It's my least favorite of what I've listed, but your tastes may vary.

For home use, I find that making 2-quart bottles of powdered drinks works well. Crystal Lite is certainly on the top of my list, and Kool-Aid has a number of sugar-free varieties.

Finally, a few companies make individual serving packets of their powdered drink products. I keep in my vehicle a dozen or so tiny packets of Crystal Light. If I'm going into a restaurant that might not serve a paletable diet drink, I bring one in, order water, and put in the powder. You can do the same with iced tea.

Good luck!

In addition to the general terms set out above, you are prohibited from using the Service for activities that include, but are not limited to:

• Sharing of your Account UserID and password for the purpose of concurrent login sessions from the same Account.
• Causing an Internet host to become unable to effectively service requests from other hosts.
• Running and/or hosting server applications including but not limited to HTTP, FTP, POP, SMTP, Proxy/SOCKS, and NNTP.
• Analyzing or penetrating an Internet host's security mechanisms.
• Forging any part of the TCP/IP packet headers in any way.
• Committing any act which may compromise the security of your Internet host in any way.

From the Bell Sympatico acceptable use policy.

The wonderful peer to peer Internet is under attack from many directions; commercial service discrimination is just one - and IMHO, it would be more like the power company deciding how much (if any) juice and of what quality they'll supply, depending on who manufactured my toaster, kettle, TV etc. than the KFC/Pepsi analogy given by Wu.

John Walker describes other, related threats here: http://www.fourmilab.ch/documents/digital-imprimat ur/

A few years ago when I was shopping for wedding rings, I came across a ring-selling website with instructions to wrap a string around your finger, then HOLD THE STRING UP TO THE SCREEN (!!) where there was a PICTURE OF A RULER, and that was supposed to tell you your ring size. (Classic. Wish I still had the link....)

Also, I have a Dell Inspiron laptop with a 15", 1920x1200 screen, which is unbelievably great for text. There's a global setting in Windows XP for a resolution multiplier (for web browsers, etc.) which I set to 125% so I could read web pages more comfortably. But Internet Explorer rendered web images using NEAREST-NEIGHBOR resampling, which made websites look utterly awful! You'd think with 256MB graphics cards they could at least do decent scaling, sheesh...

That said, a friend of mine has a PowerMac G5 hooked up to one of the 22" 3840x2400 monsters, and it is a thing of beauty (with the right software). I'm waiting til I can get a cell phone with WHUXGA resolution. (That's 7680 x 4800.) Only at that resolution can one truly appreciate the beauty of Tetris.

If MS does manage to 'conquer the internet', that would be like the Catholic church successfully conquering that irritating 'printing press' when it first showed up.

Yes.

Fences are necessary to prevent your sheep from wandering into a neighbouring field and getting all mixed up, maybe trading dangerous ideas.

Do you feel safer now? baah

Well done.

Now for those wishing extra reading, Google for "Transfer Pricing for Intangible Property under Section 482"

That is Internal Revenue Code (IRC) Sec 482 (26 U.S.C. 482).
Explained in more depth in Treasury Regulation 1.482-1(a)(1), et al. (scroll down).

It should be noted that Sec 482 covers both tangible and intengible proprty, & domestic and international transfers. Also, note that the US is odd in that it taxes citizens and corps on theiir worldwide (not just domestic) income (see IRC Sec. 61, "from whatever source derived").

He should have read Cryptonomicon and used a one time pad http://en.wikipedia.org/wiki/One_time_pad If he has the time to tell his folks what the substitution cipher is, he can give them pads. Though getting random data from Hotbits http://www.fourmilab.ch/hotbits/ may be a pain in the bits.

Yeah and IPv6 is also the END OF INTERNET ANONYMITY.

Read this and think about it: http://www.fourmilab.ch/documents/digital-imprimat ur/

It'll change your outlook on the future of the internet and maybe you'll start to take this seriously. They (being the government, the MPAA, your boss, anybody) will be able to track down and punish you for exercising your rights with relative ease. It could become a digital dark age and for that reason I'm damned glad IPv4 and the supposed inconveniences still make up the bulk of our infrastructure.

Also, please consider that the delay of HDTV may have been more due to ridiculous pricing, which continues to this day, and people like me who understand exactly what we'd be giving up (ability to timeshift, our pre-exitisting content, the stable (as in, not changing every couple years to sell us newer and costlier equipment while simultaneously shutting out everybody else) NTSC specification, etc) and sticking with old technology than any regulatory red tape or shortsightedness.

...here's a link to the Hacker's Diet discussed on /. on on many earlier occasions. It helped me lose (40lbs) (albeit in combination with modified low-carb diet) ...maybe it'll help somebody else out of a 200lb mess.

There are plenty of sources closer to us that require less bells of whistles. Thermal (amplifier) noise? Radioactive decay?

Read.

The only innovation Skype did was working around NATs. Beating ugly hacks with ugly hacks just for the sake of short-term luser-friendliness. Bleh.

We had dozens of VoIP programs a long time before Skype; what made them unpopular were troubles caused by ISPs. The end-of-life announcement of SpeakFreely is a good read.

Basically, the #1 reason why IPv6 is not widely deployed yet is that it makes VoIP and peer-to-peer work flawlessly, something that goes against the concept of tiered internet. Those "major network companies" you're speaking of are our enemies, not friends.

Perhaps this article will clarify Microsoft's view of Java for you:

http://news.com.com/2009-1001-215854.html

Also, this document describes Microsoft's apparent (lack of) regard for HTML, of all things:

http://www.fourmilab.ch/webtools/demoroniser/

Oh, hell -- just go to this website, read 'em and weep:

http://www.microsuck.com/

To put it bluntly, Microsoft has absolutely no regard for open, broadly supported standards because they hinder its program of total, absolute domination of the computer markets. Lest you think I'm just a ranting anti-Gates nutjob, here's a quote from a pro-Microsoft puff piece that ran as a cover story in Time magazine: "Microsoft's goal is to have some version of Windows ...running on every computer, everywhere." THAT, by definition, is a monopoly. (Wonder why that little bit of info wasn't introduced in the federal anti-trust case?...)

In fact, Microsoft can't even stick to its *own* standards! Look at how they deliberately break support for filetypes of older versions of their apps, coercing Microsoft customers into purchasing newer, costlier, fatter, and *buggier* versions -- otherwise their valuable documents would become unreadable to everyone else who climbed the perpetual upgrade ladder! Gee, thanks Bill Gates, now I have both Steve Jobs *and* you on my Hope-They-Die-A-Nasty-Death list.

Btw, this is a long-disgruntled Apple II user talking here. Steve Jobs can take his iPod *and* his iMac and shove 'em!

To start with, if the apparent rest mass changed then I could easily tell how fast I was going by measuring the rest mass of a particle at rest relative to me.

No, you can't. You can easily find out how much energy you have by knowing your "rest mass." But the very definition of "rest mass" implies that you're assuming some velocity to be 0. There's no "absolute" rest frame, just whatever you've determined to be 0.

A particle's mass is the same to any observer at rest relative to that particle. A particle's mass is the same to any observer at rest relative to that particle.

No, you won't, that much I'm sure of. All observers at rest relative to that particle will agree on it's mass. Observers at different speeds (vastly different) will not agree on that mass. I'll continue on this, later

if you're traveling at relativistic speed (relative to, say, Earth), everything inside your space ship will be exactly as it would be if you were not moving.

Actually, the universe will look very much different. For one, the galaxy would be much smaller. Everyone remembers time dilation, but they don't remember distance contraction. Take the numbers from the Oh-My-God Particle since I don't want to calculate numbers to an example myself :) In our time-frame, Alpha Centauri is 4.36 light-years away. So, it would take something traveling at the speed of light 4.36 years to get there. That particle is actually traveling slower than light, but if you were traveling at that speed, it would take you only 0.43 ms in your frame to get there. Why is that? The distance is much smaller. The universe would look very different.

I think the problem here is that you're seeing speed as the absolute. You say that my explanation would allow you to tell "how fast you were going" and I'm trying to say that, at relativistic speeds, that's not a useful measure. You talk about energy something has instead. What is speed? It's distance / time it takes to travel. But if you're on earth, you don't agree on the distance or the time with someone traveling at c.

Also, you know that bit about the speed of light being a constant? That means that it's a constant in all time frames. If you see a photon traveling at c, you're going to measure it's speed as c if you're traveling at 0.1c or if you're traveling at 0.999999999c. You can never "catch up" with it.

And if another intelligent race n lightyears away is wondering what in the hell you did doing exactly n years ago, why that's a real screwup. Bonus points for getting noticed in another galaxy.

This is what I figure the Oh-My-God Particle must have been.

Regarding "Objects coming towards us will never be going that fast.", check http://www.fourmilab.ch/documents/ohmygodpart.html for an intresting read.

"Of course, we also don't have Large Hadron Colliders all over the universe, smashing particles together with enormous speed and accuracy, do we?"

The universe can easily put our best efforts to shame. For example, the Oh My God particle. If constant bombardment by these sorts of particles hasn't yet destroyed us, it's doubtful anything we do will make it worse.

What ultimately put my mind at ease with regard to all of these "what ifs" is the recognition that cosmic rays routinely smash into the Earth with energies that we can still only dream of; for instance, see the Oh-My-God particle, an impact event still several orders of magnitude in energy above what we can produce in a lab. If an impact event could produce a black hole that could swallow a planet, the Solar System and indeed the entire universe would be nothing but a bunch of black holes of various sizes orbiting each other, as every massive body has long since been hit with at least one particle sufficient to start the black-hole or strangelet putative chain reaction.

Seeing as how every massive body in the universe has been hit with umpteen bajillion of these impacts, yet massive bodies remain, it would seem the probability of this occurring is effectively 0.

A priori, it's not necessarily a wrong idea. But the evidence is pretty clear that it's not a problem.

It's a scientific fact that obesity is rarely caused by "lack of control". In order for overeating, or binge eating, to be a significant cause of obesity, you have to eat so much that you're more likely to die from overconsumption.

Obesity is more often caused by combining the following: Undereating, Eating nutrionally-deficient foods, and a sedentary lifestyle.

No it isn't. Dude where the hell did you get this? Don't you understand the physics? It is impossible to gain weight when you are eating less calories than you are using. So if you are "Undereating" you must lose weight! Every self-respecting geek should read the Hackers Diet before posting bull like this on /.

My advice? Get up, go outside, eat something besides pop and chips, and stop starving yourself out of guilt. Also, a positive mental attitude seems to have a huge impact.

That however, is good avice.

both good points. Sleep is always overlooked! Although the only real way to lose weight is eat less + exercise more, as someone who was once heavy then lost a significant amount of weight and kept it off it became clear that there isn't a linear relationship between effort and results.

At least for me there were certain "weight plateaus" where it took longer to lose 5 lbs than at other times. Conversely, once in a plateau it was relatively easy to stay there as it required a certain amount of effort to gain weight. This so-called virus perhaps affects the body in a similar fashion, but if such a virus exists my interest would be why do some people have it but not others? What is the transmission vector?

There's an great website by John Walker (founder of Autodesk) called The Hackers Diet that explores the nature of weight from a chemical/engineering perspective. Also provides a series of Excel spreadsheets to monitor weight loss/gain

P.S. I noticed your previous post about physics lectures. You might find this link to be of great interest. It kind of helps visualize the Special Theory of relativity.

This is the first computer virus. From 1975. With source code.

The Oh-my-god particle had an energy of 3.2 x 10^20 eV, whereas RHIC can only get particles up to 10^11 eV/nucleon (~ 2 x 10^13 eV for gold). For 4.55 billion years Nature has been performing experiments at least 10 million times more energetic than anything we can do without catastrophe.