Removing the natural constants G and c we're left with the dependency relation r=2m.
That says that if any given spherical mass is compacted to within a given radius, it acquires an event horizon (at the radius r), and earns the name "black hole". The critical radius at which this is supposed to happen is proportional to the amount of mass involved. Note that the equation has no lower limit to the amount of mass required.
Actually, lots of people who know something about evolution are still debating some of the more interesting details.
It seems that "vanilla" DNA gene-inheritance isn't the whole story. There's also maternal immune-system response inheritance, maternal mitochondrial genetic material, various "genetic switch" settings that seem to be heritable, and so on. Did you know that your cells are supposed to sometimes "remember" which parent a given gene came from, and "play" it differently as a result?
There's all sorts of fascinating "small print" relating to heritability and gene expression that's still being uncovered. Epigenetics is a fascinating field.
If you think about your life as an exercise in spacetime geometry, then you leave a kind of slug-trail behind you. Everything that you do is preserved within that 4D structure. Even when the Sun is burned out and the human race is gone, your individual slug-trail will still be there, holding the details of every good and bad thing you ever did.
Same thing with the human race. A massively entwined mesh of billions of silvery slug trails weaving between each other in 4D, charting every peak of civilisation, and every low point.
Sure, at some point, the faded echoes of the ended mesh tail will become too indistinct for others to read or decipher, but that doesn't matter. The record is still there even if there's nobody else who can read it. Individually and collectively, we're all carving our own individual trails directly into the fabric of spacetime.
I like to make a comparison with "Space Invaders".
Space Invaders is an addictive game. People used to get obsessed with it.
In Space Invaders, you never win. The aliens never give in and declare you their leader and give you a ticker-tape parade. A game of Space Invaders ends, when, inevitably, you die.
So why was it so popular? Because it was a challenge to take the odds that the game threw at you, and make the very best of them that you possibly could. Some people played competitively to get the best hi-score they could, others just played because the beeps and the aliens and the moving things and new things that appeared at higher levels were fun. For some it was about testing themselves, or about the adrenalin fix, for others it was about discovery, and for another set, it was simply about the joy of experiencing something new.
The apparent position of the infallen matter is partly observer-dependent. If you're distant and stationary and non-accelerating, you see the infallen matter appearing to accumulate as a shell whose location appears to converge on but never quite reach the event horizon. But if you allow yourself to freefall into the hole, you see that earlier matter to be falling in, in front of you.
Yes, you're right. You are entirely mistaken about the nature of black holes. (wink)
A black hole doesn't require incredible mass, current theory says that we should be able to make them in just about any size we like.
We expect the things to form spontaneously when there's a very large amount of mass in one place, so it should be very much easier to create a black hole if you have vast amounts of mass to play with...
... But theory also says that you should be able to make them out of teeny amounts of massenergy, provided that you have some way to concentrate that massenergy to some truly absurd intensities.
And creating extreme massenergy concentrations is exactly what the LHC is designed to do when it slams particles into each other.
The theoretical argument for LHC being safe isn't that it definitely couldn't produce black holes, its that quantum mechanics seems to say that any teeny black holes that it might create would have to radiate away all their massenergy as Hawking radiation and disappear in a vanishingly short amount of time.
For scientific theories at the forefront of technology, there have been a tremendous number of mistakes made, as in, ALL the scientists were wrong.
Yep! In the 1960s, it was considered proved beyond doubt that black holes gave off zero radiation and were immortal.
We now say that even if the LHC generates micro-black-holes, its not a safety issue, because QM now tells us that black holes must radiate, and that tiny black holes should radiate so intensely that they ought to blow themselves apart before they have the chance to do any serious damage.
I'm personally a great fan of the Hawking radiation idea, But it's slightly sobering to realise that we're now effectively betting the planet on the idea that the assurances of the previous generation of physicists about the proven behaviour of black holes, apparently backed up by watertight mathematical proofs... were essentially worthless.
So there's a strong precedent on this subject for an entire community of physicists being sure of a result that supposedly couldn't possibly be wrong, but which turned out to be wrong after all. In the context of LHC and safety certification, this is slightly unfortunate.
LHC isn't doing quite the same thing as natural high-energy particle collisions. It's producing a high density of organised particle collisions, for a sustained amount of time, in a region where some of the products can hang about because they can have low inertia in the lab frame, and where any charged products are then affected by the magnetic containment system.
That may or may not make a difference.
If it does make a difference, and if there's some sort of freak chain reaction or interaction reaction that can only occur when short-lived charged collision-products have a chance to combine, then you won't be able to dismiss the possibility of that "compound event" by looking at the physics of individual particle-collisions and noting that nothing disastrous seems to happen.
Nothing disastrous happens when individual atoms of U235 decay, either. But this doesn't mean that these harmless little U235 atoms are still harmless when you assemble a lot of them together, and maybe surround them with a neutron reflector and some sort of device that's capable of functioning as a short-term containment device.
Do that and the little atoms are no longer harmless: they're now part of a functioning nuclear fission bomb.
Is there a corresponding reaction that happens when clusters of charged microblackholes encounter one another in an orderly way within a high-intensity magnetic containment field? I have no idea, but I'd suggest that most physicists have no real idea either.
What we do know though, is that the odds of that hypothetical compound effect happening at LHC can't be calculated by pointing out that individual naturally-occurring high-energy particle collisions don't cause disastrous consequences. When you're dealing with compound events, you can't calculate the probability by taking a 1/n fraction of the full reaction, calculating the probability of a given event for that situation, and then multiplying by n. The odds of one fiftieth of the critical mass of plutonium exploding spontaneously on a lab table are probably effectively zero. Multiply that mass by 100 (and add containment) and the odds of a detonation aren't "100*zero" they're pretty much a certainty.
What concerns me here is not that I have any reason to believe that these hypothetical compound reactions should happen, but that particle physics guys don't seem to be asking the right questions. They're using safety arguments that we know are worthless in the sorts of particle physics situations that we know are dangerous. Similar arguments have famously given us wrong answers before.
Ah, but in this case, the "doomsayers" are working on the basis of the best expert scientific knowledge... forty years ago.
The idea of the "immortal" black hole wasn't dreamed up by conspiracy theorists or bad science fiction authors, it was developed and taught as mathematically proven fact in university physics courses. Back in the 1960's one of the surest things in physics was supposed to be that black holes had precisely zero radiation. This is part of why, when Hawking gave his first lecture on Hawking radiation, a well-known author of a book on black holes pointedly stood up and walked out of the lecture declaring that Stephen Hawking was talking complete rubbish.
So you can't really complain when the public feel a bit confused and reckon that they're receiving mixed messages... because they are. The physics community assured them that a particular thing was mathematically proven beyond doubt to be absolutely impossible, with 100% certainty, and then they heard about the LHC, and then they were assured that LHC was safe because that same thing was known to be inevitable, with near 100% certainty.
You can't blame them for comparing the two conflicting stories and deciding that perhaps some of these "facts" about theoretical physics need to be taken with a grain of salt.
I suppose that you could blame the public for being insufficiently up-to-date with current scientific knowledge... but in my experience, most of the physicists I was coming across online in the in the 1990's didn't understand Hawking radiation either, and some refused to believe that what they'd been taught in uni as fact was now not considered correct by the top guys. I seemed to spend a lot of my time online in the 1990s trying to persuade mainstream physics people to please forget about what they'd been taught at uni and to check the current literature to see how many of the old "facts" had changed. Some of these guys were actually teaching university physics in major institutions.
So it's quite rational for the public to be sceptical about LHC safety assurances. Its entirely logical for them to ask: You guys were completely wrong before... how do we know that you're not completely wrong again now? It's also reasonable for them to note that LHC scientists may have a incentive to believe that the LHC is perfectly safe whether it is or not - that's just human nature. Experts who are heavily invested in a process sometimes have the ability to convince themselves that everything is fine even when a disaster has started to obviously unfold.
Remember, in the last few years, authority-figures assured the public that Iraq had an active WMD programme, that the invasion of Iraq would be straightforward, and that the US economy was just fine.
When the public choose to be sceptical about expert assurances based on their assessment of the experts' "need to believe", then that scepticism isn't always irrational.
Mmm, but a good argument that stable configurations aren't known to spontaneously arise in Nature isn't quite the same as arguing that they can't arise in the sorts of highly-artificial, highly ordered situations that we like to create in labs.
( Hmmm. I wonder what might happen if you drop a micro-black-hole into a vat of Bose-Einstein condensate? )
Well, we'd never witnessed a nuclear fission explosion until we built the first atom bomb. Just because we'd never knowingly seen an explosive nuclear-fission chain reaction in Nature didn't mean that such a thing wasn't possible.
Unstable heavy isotopes were decaying within the earth quintntzillions of times a second without our seeing any explosions, and the expected concentration of heavy metals at the Earth's core somehow resisted the urge to blow the planet apart.
This didn't mean that it was "proved" that an A-bomb mechanism was harmless and couldn't possibly explode. It just meant that in order to turn a reasonably common effect (nuclear decay) into something with potentially catastrophic consequences, we needed to create a special, artificial, orderly convergence of circumstances that wouldn't normally happen by itself in Nature, namely,
an abnormal concentration of events within a small spacetime volume, and
an enclosing containment system (to artificially delay the the time at which the start of a chain reaction disrupted condition (1)).
Does this combination of features sound at all familiar?:)
Event horizon formation is a function of both mass and density. You can use a huge mass of low-density material, or a smaller mass of high-density material.
Suppose that you take a car, and try to measure its surface gravity. It's going to be absurdly small. The reason for this is that there's a limit to how close you can get to the car's total massenergy. If you get really close to an atom in the front bumper, you're still several feet away from the atoms in the rear bumper. Move closer to the rear of the car, and you move further away from the front. You can think of the car as a distributed fuzzy cloud of massenergy, with an effective lower limit to the average proximity that you can achieve to its total mass.
Now squash the car into a 1cm cube. You can now get to about a ~1cm average distance of the total mass, which wasn't possible before. The surface gravitational field intensity is now larger for the same amount of mass. You have the same number of fieldlines, but squashed into a smaller region.
Now crush the 1cm cube into a half-centimetre cube. It has the same number of gravitational fluxlines as before, but the new cube has one quarter of the earlier surface area, so the flux density exiting that surface is four times greater. Each time you half the dimensions, the surface flux density quadruples. Squash it all the way down to a dimensionless point, and the surface gravitational field intensity is infinite. At some distance around that point, there'll be a critical radius where the surface gravitation (compared to the background) is just strong enough to stop light, and that's your event horizon radius. Under current theory, you've then got yourself a "micro" black hole.
This doesn't require the massenergy to be really compacted all the way to a dimensionless a point, just to less than the critical radius.
If you want to create an event-horizon-bounded region, it certainly helps if you have a huge amount of matter, but its not entirely necessary.
Othe recommended books
on
The Zen of SOA
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· Score: 5, Funny
Hey, this is fun!
:)
"What would Jesus sell?"
"The Jihadi of Direct Sales Marketing"
"The Sinai Law: The Ten Commandments of Business Strategy"
"Cheops' Law: Building the People Pyramid"
"The Magic Circle: How Personal Networking can Work For You!"
"The Personnel Manager's Zodiac: The 12 basic employee archetypes, and how to deal with them."
"The Feng Shui of Downsizing"
(sample wisdom: study the office floorplan carefully. Identify the employees who sit in the corners of the room. Sack them first).
Damn, that's six potential business best-sellers straight away!
Re:First Lesson in writing a Review
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The Zen of SOA
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· Score: 1
I'm intrigued by this idea of a "sea-level executive". Is that a senior exec whose perfomance is so bad that the shareholders have thrown him into the sea, with a block of concrete chained to his ankles so that his nostrils are just above the water, so they can watch as the tide comes in?
It's about packaging and repackaging everything in the IT world as derivative "services". The idea is that the end-user finds it easier to buy prepackaged services (and services that are bundles of other prepackaged services) than a miscellaneous range of things that they don't necessarily understand. Repackaged "derivative" products are supposed to be easier to sell.
You know, kinda like the banking sector did with mortgages recently.
Perhaps the default behaviour for a business email application should be for the effect of the "send" button to actually be "send this email in n minutes time, provided that the user doesn't change their mind before then".
You'd then also have a menu-only "Express Send" option for more time-critical emails that really do have to be sent Right Now, and when the application was closed down, it'd check whether there were any unsent messages in the "waiting" folder and give the user a "There are unsent messages: do you want to send these now?" -type alert box.
This sort of default safety-delay feature wouldn't catch all mistakes, but it'd catch some, and power users would still be able to go into their settings menu and change "n" to zero if they hated it.
Actually, Firefox has a built-in non-functional spell checker.
I'm using a pretty recent download and install:
sdkfjlskfjl qwertyuiop Murcosoft bwbies.
Nope, no red lines, even though I've made sure that the spell-checker is set to to "check as I type" with a nice little tick in the appropriate box.
See, although technically the spell-checker is built-in, the dictionaries are addons, and the program doesn't warn you that although the spell-checker feature is enabled, it won't actually do anything if there isn't a suitable add-in downloaded and installed. It's not smart enough to "grey-out" the spell-checker enable/disable box when there are no dictionaries installed, to warn the user that there's an issue and that the spell-checker won't function until it's resolved.
I now download a dictionary, allow FF to reboot, and try again. Now it works. The downloaded UK FF dictionary still doesn't recognise "Firefox" as a valid word, though...
When the State Department sent their message to all employees telling them that using the wrong buttons on their email programs would now count as a disciplinary offence, do you think that that the senior exec who sent that message sent it to everyone as a TO:, as a CC:, or as a BCC: ?
... oh, and obviously, because it has no optical drive of its own, many Eee Box users are going to need either an external USB drive, or access to their CD/DVD data over a network, or some sort of USB transfer medium. I installed a couple of apps from CDR by telling my (old, misbehaving) laptop to share its DVD drive over the network, and then using the laptop as a glorified external optical drive.
Programs often don't care too much where you install them from, but I guess there may be exceptions.
I usually keep two main PC's hooked up to a KVM switcher - a slow (very quiet) one for email, webbrowsing, wordprocessing etc, and a more powerful (noisy) one for occasional more high-powered stuff like video editing and rendering. The more powerful one usually doesn't get allowed near the internet. My "quiet" machine used to be an old Sony laptop, half-opened and propped up like a letter "A", with external monitor and keyboard, but that's getting a bit iffy, so the EeeBox has replaced it.
Possible Eee Box criticisms:
When you switch it to standby (e.g., when you want to call it a night and you have unsaved files and webpages open), its very bright blue power light flashes, which is a distraction if it's in a bedroom and you're trying to sleep. In those situations, I hang a sock over it.
I'm not sure how much use the SplashTop thing is. I thought that it might be handy for adjusting XP's partition sizes, but the HD partitions are formatted as NTFS, which SplashTop doesn't read. So for the XP machine, Splashtop's file manager can access external media, but not the onboard HD unless you do some reformatting. Oh well, call it a security feature.
I didn't realise that it had SplashTop 'til I took it out of the box, so I can't really complain. Maybe it's handy for Skype users.
My main backup drives are Firewire, so it's a shame (for me) that the EeeBox doesn't have 1394, and that there's no obvious way to retrofit it. But I can still connect those drives on the other PC(s) and access them over the network.
The supplied default formatting on mine was forty gig NTFS for the c: WinXP partition, about three gig for a hidden recovery partition, and the remaining ~110 gig as a single NTFS d: partition. I quickly replaced d:. I've seen one user complain that 40Gig is too small for a c: partition... it suits me just fine, but I tend not to install many huge programs (no big games), and I like to keep my data files off c: anyway.
Those are about the only negatives I can think of. I haven't tried running HD video on it, and I haven't tried it with a digital USB TV stick, so I can't comment on how good it might (or might not) be for serious video. I also haven't played any serious games on it. I loved the fact that it came with the VESA bracket. Haven't used the supplied stand.
Some people might be disappointed that it has an HDMI socket rather than VGA - it comes with the required VGA adaptor, but this makes the resulting monitor cable assembly stick out further than you might expect, making the thing require more room than its dimensions suggest if you're using it with a VGA monitor. Not an issue for me (my "box" is bolted to the back of a 17" monitor), but might be a disappointment for someone wanting to sit it facing forwards on a narrow bookshelf.
Other than that it's difficult to fault. Mic input but no separate line input. Runs surprisingly cool, and is very quiet (so far). Every now and then it gives a little quiet sigh, and that's about all I hear from it. WiFi and LAN work fine. Graphics can rotate the screen into portrait mode, if you want to work on large single pages. The (mostly) convective cooling design expects the box to be mounted vertically, which probably limits some of the more creative mounting possibilities.
What I haven't yet gotten around to working out is (a) whether I can stop that dratted flashing LED in standby mode, and (b) why XP SP3's Task Manager shows two CPU graphs, side by side with slightly different activities, even though it's supposed to be a single-core machine.
So for me, no nasty surprises and a few nice ones (the VESA bracket is seriously heavy!). But a lot of people will be interested in how well it copes with more demanding "media centre" jobs (like displaying and transcoding incoming DTV signals live, to something like mpeg4), and I'm afraid I haven't tried anything like that on it yet.
A few weeks ago I needed a simple cheap-as-possible WinXP PC in a hurry, so I ordered an Eee Box, and it turned up the next day. A few UK retailers seemed to have plenty of stock. There don't seem to be any supply problems in the UK, but then again, hardly anyone in the UK seems to know that it exists. I didn't - I only found out about it by accident via Wikipedia, so I was really surprised to find that it was already buyable.
Price was slightly less than the lowest prices at the time for a Linux Eee PC 900 netbook.
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As the other poster said, r=2Gm/c^2
Removing the natural constants G and c we're left with the dependency relation r=2m.
That says that if any given spherical mass is compacted to within a given radius, it acquires an event horizon (at the radius r), and earns the name "black hole". The critical radius at which this is supposed to happen is proportional to the amount of mass involved. Note that the equation has no lower limit to the amount of mass required.
It seems that "vanilla" DNA gene-inheritance isn't the whole story. There's also maternal immune-system response inheritance, maternal mitochondrial genetic material, various "genetic switch" settings that seem to be heritable, and so on. Did you know that your cells are supposed to sometimes "remember" which parent a given gene came from, and "play" it differently as a result?
There's all sorts of fascinating "small print" relating to heritability and gene expression that's still being uncovered. Epigenetics is a fascinating field.
Same thing with the human race. A massively entwined mesh of billions of silvery slug trails weaving between each other in 4D, charting every peak of civilisation, and every low point.
Sure, at some point, the faded echoes of the ended mesh tail will become too indistinct for others to read or decipher, but that doesn't matter. The record is still there even if there's nobody else who can read it. Individually and collectively, we're all carving our own individual trails directly into the fabric of spacetime.
What you'd like your trail to say is up to you.
Space Invaders is an addictive game. People used to get obsessed with it.
In Space Invaders, you never win. The aliens never give in and declare you their leader and give you a ticker-tape parade. A game of Space Invaders ends, when, inevitably, you die.
So why was it so popular? Because it was a challenge to take the odds that the game threw at you, and make the very best of them that you possibly could. Some people played competitively to get the best hi-score they could, others just played because the beeps and the aliens and the moving things and new things that appeared at higher levels were fun. For some it was about testing themselves, or about the adrenalin fix, for others it was about discovery, and for another set, it was simply about the joy of experiencing something new.
Same thing with life.
The apparent position of the infallen matter is partly observer-dependent. If you're distant and stationary and non-accelerating, you see the infallen matter appearing to accumulate as a shell whose location appears to converge on but never quite reach the event horizon. But if you allow yourself to freefall into the hole, you see that earlier matter to be falling in, in front of you.
A black hole doesn't require incredible mass, current theory says that we should be able to make them in just about any size we like.
We expect the things to form spontaneously when there's a very large amount of mass in one place, so it should be very much easier to create a black hole if you have vast amounts of mass to play with ...
And creating extreme massenergy concentrations is exactly what the LHC is designed to do when it slams particles into each other.
The theoretical argument for LHC being safe isn't that it definitely couldn't produce black holes, its that quantum mechanics seems to say that any teeny black holes that it might create would have to radiate away all their massenergy as Hawking radiation and disappear in a vanishingly short amount of time.
For scientific theories at the forefront of technology, there have been a tremendous number of mistakes made, as in, ALL the scientists were wrong.
Yep! In the 1960s, it was considered proved beyond doubt that black holes gave off zero radiation and were immortal.
We now say that even if the LHC generates micro-black-holes, its not a safety issue, because QM now tells us that black holes must radiate, and that tiny black holes should radiate so intensely that they ought to blow themselves apart before they have the chance to do any serious damage.
I'm personally a great fan of the Hawking radiation idea, But it's slightly sobering to realise that we're now effectively betting the planet on the idea that the assurances of the previous generation of physicists about the proven behaviour of black holes, apparently backed up by watertight mathematical proofs ... were essentially worthless.
So there's a strong precedent on this subject for an entire community of physicists being sure of a result that supposedly couldn't possibly be wrong, but which turned out to be wrong after all. In the context of LHC and safety certification, this is slightly unfortunate.
That may or may not make a difference.
If it does make a difference, and if there's some sort of freak chain reaction or interaction reaction that can only occur when short-lived charged collision-products have a chance to combine, then you won't be able to dismiss the possibility of that "compound event" by looking at the physics of individual particle-collisions and noting that nothing disastrous seems to happen.
Nothing disastrous happens when individual atoms of U235 decay, either. But this doesn't mean that these harmless little U235 atoms are still harmless when you assemble a lot of them together, and maybe surround them with a neutron reflector and some sort of device that's capable of functioning as a short-term containment device.
Do that and the little atoms are no longer harmless: they're now part of a functioning nuclear fission bomb.
Is there a corresponding reaction that happens when clusters of charged microblackholes encounter one another in an orderly way within a high-intensity magnetic containment field? I have no idea, but I'd suggest that most physicists have no real idea either.
What we do know though, is that the odds of that hypothetical compound effect happening at LHC can't be calculated by pointing out that individual naturally-occurring high-energy particle collisions don't cause disastrous consequences. When you're dealing with compound events, you can't calculate the probability by taking a 1/n fraction of the full reaction, calculating the probability of a given event for that situation, and then multiplying by n. The odds of one fiftieth of the critical mass of plutonium exploding spontaneously on a lab table are probably effectively zero. Multiply that mass by 100 (and add containment) and the odds of a detonation aren't "100*zero" they're pretty much a certainty.
What concerns me here is not that I have any reason to believe that these hypothetical compound reactions should happen, but that particle physics guys don't seem to be asking the right questions. They're using safety arguments that we know are worthless in the sorts of particle physics situations that we know are dangerous. Similar arguments have famously given us wrong answers before.
The idea of the "immortal" black hole wasn't dreamed up by conspiracy theorists or bad science fiction authors, it was developed and taught as mathematically proven fact in university physics courses. Back in the 1960's one of the surest things in physics was supposed to be that black holes had precisely zero radiation. This is part of why, when Hawking gave his first lecture on Hawking radiation, a well-known author of a book on black holes pointedly stood up and walked out of the lecture declaring that Stephen Hawking was talking complete rubbish.
So you can't really complain when the public feel a bit confused and reckon that they're receiving mixed messages ... because they are. The physics community assured them that a particular thing was mathematically proven beyond doubt to be absolutely impossible, with 100% certainty, and then they heard about the LHC, and then they were assured that LHC was safe because that same thing was known to be inevitable, with near 100% certainty.
You can't blame them for comparing the two conflicting stories and deciding that perhaps some of these "facts" about theoretical physics need to be taken with a grain of salt.
I suppose that you could blame the public for being insufficiently up-to-date with current scientific knowledge ... but in my experience, most of the physicists I was coming across online in the in the 1990's didn't understand Hawking radiation either, and some refused to believe that what they'd been taught in uni as fact was now not considered correct by the top guys. I seemed to spend a lot of my time online in the 1990s trying to persuade mainstream physics people to please forget about what they'd been taught at uni and to check the current literature to see how many of the old "facts" had changed. Some of these guys were actually teaching university physics in major institutions.
So it's quite rational for the public to be sceptical about LHC safety assurances. Its entirely logical for them to ask: You guys were completely wrong before ... how do we know that you're not completely wrong again now? It's also reasonable for them to note that LHC scientists may have a incentive to believe that the LHC is perfectly safe whether it is or not - that's just human nature. Experts who are heavily invested in a process sometimes have the ability to convince themselves that everything is fine even when a disaster has started to obviously unfold.
Remember, in the last few years, authority-figures assured the public that Iraq had an active WMD programme, that the invasion of Iraq would be straightforward, and that the US economy was just fine.
When the public choose to be sceptical about expert assurances based on their assessment of the experts' "need to believe", then that scepticism isn't always irrational.
( Hmmm. I wonder what might happen if you drop a micro-black-hole into a vat of Bose-Einstein condensate? )
Unstable heavy isotopes were decaying within the earth quintntzillions of times a second without our seeing any explosions, and the expected concentration of heavy metals at the Earth's core somehow resisted the urge to blow the planet apart.
This didn't mean that it was "proved" that an A-bomb mechanism was harmless and couldn't possibly explode. It just meant that in order to turn a reasonably common effect (nuclear decay) into something with potentially catastrophic consequences, we needed to create a special, artificial, orderly convergence of circumstances that wouldn't normally happen by itself in Nature, namely,
Does this combination of features sound at all familiar? :)
Suppose that you take a car, and try to measure its surface gravity. It's going to be absurdly small. The reason for this is that there's a limit to how close you can get to the car's total massenergy. If you get really close to an atom in the front bumper, you're still several feet away from the atoms in the rear bumper. Move closer to the rear of the car, and you move further away from the front. You can think of the car as a distributed fuzzy cloud of massenergy, with an effective lower limit to the average proximity that you can achieve to its total mass.
Now squash the car into a 1cm cube. You can now get to about a ~1cm average distance of the total mass, which wasn't possible before. The surface gravitational field intensity is now larger for the same amount of mass. You have the same number of fieldlines, but squashed into a smaller region.
Now crush the 1cm cube into a half-centimetre cube. It has the same number of gravitational fluxlines as before, but the new cube has one quarter of the earlier surface area, so the flux density exiting that surface is four times greater. Each time you half the dimensions, the surface flux density quadruples. Squash it all the way down to a dimensionless point, and the surface gravitational field intensity is infinite. At some distance around that point, there'll be a critical radius where the surface gravitation (compared to the background) is just strong enough to stop light, and that's your event horizon radius. Under current theory, you've then got yourself a "micro" black hole.
This doesn't require the massenergy to be really compacted all the way to a dimensionless a point, just to less than the critical radius.
If you want to create an event-horizon-bounded region, it certainly helps if you have a huge amount of matter, but its not entirely necessary.
How to leverage the principles of assassination, misinformation and demoralisation within your business structure.
The Dutch have a different acronym for Subscriber Trunk Dialling?
Book opportunity: "The Zen of Zen"?
(sample wisdom: study the office floorplan carefully. Identify the employees who sit in the corners of the room. Sack them first).
Damn, that's six potential business best-sellers straight away!
I'm intrigued by this idea of a "sea-level executive". Is that a senior exec whose perfomance is so bad that the shareholders have thrown him into the sea, with a block of concrete chained to his ankles so that his nostrils are just above the water, so they can watch as the tide comes in?
You know, kinda like the banking sector did with mortgages recently.
You'd then also have a menu-only "Express Send" option for more time-critical emails that really do have to be sent Right Now, and when the application was closed down, it'd check whether there were any unsent messages in the "waiting" folder and give the user a "There are unsent messages: do you want to send these now?" -type alert box.
This sort of default safety-delay feature wouldn't catch all mistakes, but it'd catch some, and power users would still be able to go into their settings menu and change "n" to zero if they hated it.
As in feel/felt, deal/dealt, kneel/knelt, peel/ ...(oh crap), seal/ ...(oh crap again).
Huh. English. With this many bugs, it'll never be popular.
I'm using a pretty recent download and install:
sdkfjlskfjl qwertyuiop Murcosoft bwbies.
Nope, no red lines, even though I've made sure that the spell-checker is set to to "check as I type" with a nice little tick in the appropriate box.
See, although technically the spell-checker is built-in, the dictionaries are addons, and the program doesn't warn you that although the spell-checker feature is enabled, it won't actually do anything if there isn't a suitable add-in downloaded and installed. It's not smart enough to "grey-out" the spell-checker enable/disable box when there are no dictionaries installed, to warn the user that there's an issue and that the spell-checker won't function until it's resolved.
I now download a dictionary, allow FF to reboot, and try again. Now it works. The downloaded UK FF dictionary still doesn't recognise "Firefox" as a valid word, though ...
(GRIN)
Just wondering.
Programs often don't care too much where you install them from, but I guess there may be exceptions.
I usually keep two main PC's hooked up to a KVM switcher - a slow (very quiet) one for email, webbrowsing, wordprocessing etc, and a more powerful (noisy) one for occasional more high-powered stuff like video editing and rendering. The more powerful one usually doesn't get allowed near the internet. My "quiet" machine used to be an old Sony laptop, half-opened and propped up like a letter "A", with external monitor and keyboard, but that's getting a bit iffy, so the EeeBox has replaced it.
Possible Eee Box criticisms:
I didn't realise that it had SplashTop 'til I took it out of the box, so I can't really complain. Maybe it's handy for Skype users.
Those are about the only negatives I can think of. I haven't tried running HD video on it, and I haven't tried it with a digital USB TV stick, so I can't comment on how good it might (or might not) be for serious video. I also haven't played any serious games on it. I loved the fact that it came with the VESA bracket. Haven't used the supplied stand.
Some people might be disappointed that it has an HDMI socket rather than VGA - it comes with the required VGA adaptor, but this makes the resulting monitor cable assembly stick out further than you might expect, making the thing require more room than its dimensions suggest if you're using it with a VGA monitor. Not an issue for me (my "box" is bolted to the back of a 17" monitor), but might be a disappointment for someone wanting to sit it facing forwards on a narrow bookshelf.
Other than that it's difficult to fault. Mic input but no separate line input. Runs surprisingly cool, and is very quiet (so far). Every now and then it gives a little quiet sigh, and that's about all I hear from it. WiFi and LAN work fine. Graphics can rotate the screen into portrait mode, if you want to work on large single pages. The (mostly) convective cooling design expects the box to be mounted vertically, which probably limits some of the more creative mounting possibilities.
What I haven't yet gotten around to working out is (a) whether I can stop that dratted flashing LED in standby mode, and (b) why XP SP3's Task Manager shows two CPU graphs, side by side with slightly different activities, even though it's supposed to be a single-core machine.
So for me, no nasty surprises and a few nice ones (the VESA bracket is seriously heavy!). But a lot of people will be interested in how well it copes with more demanding "media centre" jobs (like displaying and transcoding incoming DTV signals live, to something like mpeg4), and I'm afraid I haven't tried anything like that on it yet.
Price was slightly less than the lowest prices at the time for a Linux Eee PC 900 netbook.