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Anything that can be made to run under one GNU/Linux distro can be made to run under another, and slackware is no exception. Indeed, slackware is perhaps the poster child for running proprietary applications on a distro they weren't designed for. It's so homogenious that major changes are rarely needed. Since you mentioned trouble with vmware, why don't you take a look at this page which documents exactly how to install vmware on slackware liux. I've done it several times with no problems, and find it to be a walk in the park.

Olber's paradox causes no problems when considered against conventional cosmology, or the cosmology discussed in the article - have a look here.

This explanation is not affected by an actually infinite number of stars, as postulated in the article. Even in a universe only as big as the part we can observe, there are a near-enough to infinite number of stars for the purposes of the paradox anyway.

See for yourself!

Sorry :-)

In all seriousness, keep up the good work.

Rongorongo, the hieroglyphic script of Easter Island

The Voynich Manuscript, 200 pages, probably written in the 13 century

Indus Valley scripts from Mohenjo-daro in Pakistan, 4000 years ago

Etruscan

The Disc of Phaistos, from Crete, 3700 years ago

Meroitic hieroglyphs of ancient Nubia

Zapotec script
Have fun!

Check out the 'Art of Assembly Language Programming' One of the early projects is exactly this, programming a set of LED's to flash in a seqance. You can find it at webster.cs.ucr.edu

Well, this got me thinking: "What does a black hole look like from the INSIDE? What would one see from the viewpoint of the matter that was already there when the event horizon formed?"

And the answer seemed to be: "An expanding universe, starting from a very small but finite volume and expanding indefinitely, containing a large-but-finite amount of matter, which was initially compressed into an EXTREMELY dense lump - perhaps a quark fluid or denser."

This happens in Big Science, too. Neutrino detection experiments detect very few neutrinos. Most attempts to experimentally verify general relativity also have problems. (The precession of the orbit of Mercury is tiny, and mostly accounted for by effects from other planets.) But that work has been repeated multiple times using different techniques by different people, which yields some confidence. Still, there's no single killer result in either area.

As for suppressed inventions, those are rare, but they do exist. A major attempt was made by MagneTek (later Universal Manufacturing), which made old-style inductive fluorescent lamp ballasts, to suppress the electronic fluorescent lamp ballast. Litigation resulted. The lone inventor won. The verdict was for about $96 million. This created the compact fluorescent lamp industry.

This is just a shortened version of The physics Crackpot Index.

It's written for physics but seems to apply pretty well to any science...

Why don't they just use the Crackpot Index to judge them?

Absolute Zero is not the lowest possible temperature, nor is it the lower bound of the range of possible temperatures. It is actually possible to attain temperatures BELOW absolute zero, as any student of statistical thermodynamics will know.

Absolute Zero is not the lowest possible temperature, nor is it the lower bound of the range of possible temperatures. It is actually possible to attain temperatures BELOW absolute zero, as any student of statistical thermodynamics will know.

John Baez has some really good info about LIGO in several of his "This Week's Finds in Mathematical Physics" columns. week198 is the most recent to mention it. Baez is a great place to start if you like understanding connections between all kinds of different areas of math & physics (which, of course, includes everything else :)

You havn't checked back in awhile...AoA is available in the old 16 bit/DOS version, as well as an updated 32 bit/Win32 and (finally) a 32 bit /Linux version!

You havn't checked back in awhile...AoA is available in the old 16 bit/DOS version, as well as an updated 32 bit/Win32 and (finally) a 32 bit /Linux version!

You havn't checked back in awhile...AoA is available in the old 16 bit/DOS version, as well as an updated 32 bit/Win32 and (finally) a 32 bit /Linux version!

Not to be a wiseass, but glass technically isn't a solid. It's a REALLY slow flowing liquid.

That's an urban myth. Glass is probably most accurately described as an "amorphous solid", i.e. non-crystaline in structure but rigid. There is a second-order phase transition that occurs between the supercooled liquid state and the amorphous solid state, although not a dramatic change.

Actually, it's not outside the realm of possibility to consider glasses to actually be a distinctly different form of matter, neither liquid nor solid; owing largely to the fact that glasses combine the properties of both traditional solids and liquids. Disordered molecules, but rigidly bound.

Regardless, the urban myth that non-molten glass can "flow" is incorrect; in that respect it behaves like a solid.

More information, including cites, can be found here.

Well, using ALL CAPS to track crackpots is an old, old idea, it's even part of the canonical crackpot index!

Terry

screenshot

"This doesn't require any knowledge of relativity - even in Newtonian mechanics this would happen."

Newtonian mechanics says the clock disappeared 8 minutes ago. Special relativity says the clock was 8 minutes slow in the earth frame of reference.

There is no frame of reference where you can say "it actually..." because there is no frame of reference that is more correct than any other. Measurement of time and space is relative to the observer.

That's why all observers measure c relative to them as the same value in all conditions. If there were a preferred frame of reference, then c would be different for different observers. But a century of experimental evidence shows the case to be otherwise.

"No, it has ACTUALLY happened in his frame of reference, he just hasn't SEEN it yet."

If you can't see it, hear it, or otherwise proove its existence (or lack thereof), the event hasn't happened yet. The only way the observer will know that it has (will) happened is if he has some sort of prior knowledge of a pre-arranged schedule, But that foresight doesn't mean the event happens in his frame of reference any sooner. And his frame of reference is just as valid as anybody else's frame of reference.

"Again, he doesn't need to know anything about relativity to determine this, it would work the same way in Newtonian mechanics."

Newtonian mechanics say that the delay between the sun disappearing and the earth noticing will be measured as the same for all observers. Special relativity says that there is no absolute frame of reference for the measurement of time. It will be different for different people based on location and velocity relative to the event. I can give you observers that will say that that delay is anywhere between "instantaneous" and "forever," and all of these measurements will be 100% valid.

In fact, special relativity states that if an observer is able to move faster than light, they will see the earth leave its orbital path before the sun disappeared. And that observation as well would be 100% correct.

"12:00 on Earth is truly in the Past for the moving observer even though 12:00 on the Sun is Now."

You assume that one clock is "more correct" than the other two. Special relativity says that all the clocks are correct for all observers.

An earth-bound observer will see the spacecraft's clock as two minutes slow, and he will be correct. The astronaut will see the earth-bound clock as two minutes slow, and he too will be correct. They are both correct because there is no absolute frame of reference.

"No. But, when you first see the Sun peek over the horizon, the light you're seeing left the Sun eight minutes before. The fact that you aren't seeing it until now doesn't mean it didn't happen until now."

Proove it with experimental evidence. Give me hard evidence that the light I'm seeing from the sun left the sun eight minutes ago.

For every observer that you give me that says "eight minutes," I can give you an infinite number of observers that will give you an infinite number of measurements, none of which are eight minutes. And they will all have physical evidence prooving their observations.

"and determine that they really did vanish at different times"

He can compute whatever he wants. In his frame of reference, they really did disappear at the same time. His computations have no effect on the reality of the situation in his frame of reference.

"the Earth slighty before the Sun. The observer on Earth would see Earth vanish, see the Sun vanish eight minutes later, and calculate that they both vanished precisely at 12:00. They would both be correct, for their own frame of reference."

No, they're only correct for the frame of reference of the half-way point, which isn't any better than earth-based or sun-based observations. The observers can calculate whatever they want, but (barring quantum mechanics) as far as reality is concerned at their individual frames of references, there was an eight minute gap between the two occurrences. All physical evidence that can possibly be gathered by those two observers will demonstrate that eight minute gap.

It's obvious from your posts that you know little about what special relativity says. Why don't you try reading a little about the classic barn and pole scenario before you try responding again.

Couldn't you collide some matter and antimatter? If you had some mass and then it co-annihilates, it should be like turning gravity off.

No, it shouldn't. A matter-antimatter annihilation isn't really an "annihilation" in the sense that the "nihil" in "annihilation" might suggest; instead, if, for example, an electron and positron mutually annihilate, you get a pair of photons, and the total energy of the photons is equal to the total energy (rest energy, from rest mass, plus kinetic energy) of the incoming electron and positron.

The photons have a gravitational field just as the electron and positron did. (Mass isn't the source of gravity - energy and momentum, and the flow thereof, are.)

A simple method for rating potentially revolutionary contributions to physics. A -5 point starting credit.

1. 1 point for every statement that is widely agreed on to be false.
2. 2 points for every statement that is clearly vacuous.
3. 3 points for every statement that is logically inconsistent.
4. 5 points for each such statement that is adhered to despite careful correction.
5. 5 points for using a thought experiment that contradicts the results of a widely accepted real experiment.
6. 5 points for each word in all capital letters (except for those with defective keyboards).
7. 5 points for each mention of "Einstien", "Hawkins" or "Feynmann".
8. 10 points for each claim that quantum mechanics is fundamentally misguided (without good evidence).
9. 10 points for pointing out that you have gone to school, as if this were evidence of sanity.
10. 10 points for beginning the description of your theory by saying how long you have been working on it.
11. 10 points for mailing your theory to someone you don't know personally and asking them not to tell anyone else about it, for fear that your ideas will be stolen.
12. 10 points for offering prize money to anyone who proves and/or finds any flaws in your theory.
13. 10 points for each statement along the lines of "I'm not good at math, but my theory is conceptually right, so all I need is for someone to express it in terms of equations".
14. 10 points for arguing that a current well-established theory is "only a theory", as if this were somehow a point against it.
15. 10 points for arguing that while a current well-established theory predicts phenomena correctly, it doesn't explain "why" they occur, or fails to provide a "mechanism".
16. 10 points for each favorable comparison of yourself to Einstein, or claim that special or general relativity are fundamentally misguided (without good evidence).
17. 10 points for claiming that your work is on the cutting edge of a "paradigm shift".
18. 20 points for suggesting that you deserve a Nobel prize.
19. 20 points for each favorable comparison of yourself to Newton or claim that classical mechanics is fundamentally misguided (without good evidence).
20. 20 points for every use of science fiction works or myths as if they were fact.
21. 20 points for defending yourself by bringing up (real or imagined) ridicule accorded to your past theories.
22. 20 points for each use of the phrase "hidebound reactionary".
23. 20 points for each use of the phrase "self-appointed defender of the orthodoxy".
24. 30 points for suggesting that a famous figure secretly disbelieved in a theory which he or she publicly supported. (E.g., that Feynman was a closet opponent of special relativity, as deduced by reading between the lines in his freshman physics textbooks.)
25. 30 points for suggesting that Einstein, in his later years, was groping his way towards the ideas you now advocate.
26. 30 points for claiming that your theories were developed by an extraterrestrial civilization (without good evidence).
27. 30 points for allusions to a delay in your work while you spent time in an asylum, or references to the psychiatrist who tried to talk you out of your theory.
28. 40 points for comparing those who argue against your ideas to Nazis, stormtroopers, or brownshirts.
29. 40 points for claiming that the "scientific establishment" is engaged in a "conspiracy" to prevent your work from gaining its well-deserved fame, or suchlike.
30. 40 points for comparing yourself to Galileo, suggesting that a modern-day Inquisition is hard at work on your case, and so on.
31. 40 points for claiming that when your theory is finally appreciated, present-day science will be seen for the sham it truly is. (30 more points for fantasizing about show trials in which scientists who mocked your theories will be forced to recant.)
32. 50 points for claiming you have a revolutionary theory but giving no concrete testable predictions.

    © 1998 John Baez

It's not the first measurement of the speed of gravity, nor even the most accurate. But it's a new way of measuring it.

"It's much more likely the ringing comes from the air right next to the polished gong surface suddenly heating up."

Feel free to correct me if i'm wrong, but I think you are mistaken. Since I just finished my college level E&M physics class, the the photon will stike the gong forcing it to vibrate

"There's a similar confusion about what drives those "solar radiometer" things - you know, a little black-and-white paddlewheel inside an evacuated glass ball that spins when you shine a light on it? People often say the reason they run is photon momentum, when the actual explanation is that the black sides of the paddles are hotter than the white sides, so when the few gas molecules left inside the ball hit the paddles, they leave the black sides going faster than the white sides."

The reason the black moves is not because it is hotter but rather that because black absorbs light while white reflects, and if you study your momentum equations you will notice that if something absorbs an object and in another case reflects an object this will result in different forces.

I wouldn't take their word for it.

This paper [ldolphin.org] gives a good case for gravity traveling faster than light

van Flandern is a known crank. (Check out his "face on Mars" claims, too...) You can read about his errors here and here, in debates with physicists and mathematicians. Eventually, Steve Carlip (the world's leading authority on 3D quantum gravity, and a GR expert) got so sick of correcting laymen wandering into Usenet having heard of van Flandern's claims that he published a paper to debunk him once and for all.

and I'm pretty sure all the working Newtonian gravity calculations assume instantaneous gravity:

I wouldn't take their word for it.

This paper [ldolphin.org] gives a good case for gravity traveling faster than light

van Flandern is a known crank. (Check out his "face on Mars" claims, too...) You can read about his errors here and here, in debates with physicists and mathematicians. Eventually, Steve Carlip (the world's leading authority on 3D quantum gravity, and a GR expert) got so sick of correcting laymen wandering into Usenet having heard of van Flandern's claims that he published a paper to debunk him once and for all.

and I'm pretty sure all the working Newtonian gravity calculations assume instantaneous gravity:

I wouldn't take their word for it.

This paper [ldolphin.org] gives a good case for gravity traveling faster than light

van Flandern is a known crank. (Check out his "face on Mars" claims, too...) You can read about his errors here and here, in debates with physicists and mathematicians. Eventually, Steve Carlip (the world's leading authority on 3D quantum gravity, and a GR expert) got so sick of correcting laymen wandering into Usenet having heard of van Flandern's claims that he published a paper to debunk him once and for all.

and I'm pretty sure all the working Newtonian gravity calculations assume instantaneous gravity:

Consider the Earth's orbit around the Sun. It takes light about 8 minutes to travel the distance. If gravity takes that long, then the Earth should feel the tug of gravity not where the Sun is, but where it was 8 minutes ago. This should cause gravitational drag. Though this is small over short time scales, over a 5 billion (10^9) year time scale, the Earth's orbit isn't stable.

The argument continues that since the Earth's orbit appears to be stable, gravity must move faster.

I haven't heard a really good counter argument.

It's much more likely the ringing comes from the air right next to the polished gong surface suddenly heating up.

There's a similar confusion about what drives those "solar radiometer" things - you know, a little black-and-white paddlewheel inside an evacuated glass ball that spins when you shine a light on it? People often say the reason they run is photon momentum, when the actual explanation is that the black sides of the paddles are hotter than the white sides, so when the few gas molecules left inside the ball hit the paddles, they leave the black sides going faster than the white sides.

The proof of this is the direction the paddlewheel turns - it turns white-side-first, and a photon-mass explanation would have the paddle turning black-side-first. If you put a paddlewheel inside a REAL hard vacuum, with a REAL low friction bearing, and REALLY isplate it from outside vibration, it turns the right way. See here for a more coherent and complete explanation.

As for the gravity and black holes issue, Read this FAQ.

The fact that light is deflected by gravity does not imply that it has mass... but to an extent, that is a matter of definition.

Read this FAQ.

The Taylor and Hulse binary pulsar experiments (1993 Nobel Prize) which found indirect evidence for gravitational waves, also found indirect evidence for the speed of those waves -- the speed of light, to within 1%. The results being discussed here on Slashdot are merely a more recent, and less accurate, indirect measurement. Direct measurement will have to wait until the direct detection of gravitational waves (by LIGO or other experiments), when we can actually measure how long it takes a change in the gravitational field to propagate from one observatory to another.

Gravitomagnetic effects make everything work out consistently. Read this FAQ. No conservation laws or symmetries are violated. (By the way, some mass-energy is radiated as gravitational waves, and the objects do spin faster and spiral into each other, but this is an extremely weak process, visible only in closely orbiting neutron stars.)

Well, except for the whole argument that photons might have mass afterall... but...

A Google search on the mass of a photon leads to a lot of pages that discuss that to a great degree.

It is almost certainly impossible to do any experiment which would establish that the photon rest mass is exactly zero. - LINK

I'd like to see precisely where you draw the line between patterns of chemical reactions and `life'. Here's a really interesting introduction to self-replicating structures even simpler than viruses: Subcellular Life Forms. I think it does a lot to show that the classification of things as `alive' or `not alive' is just an arbitrary human distinction.

Who cares about hydrogen? Why not base everything off of the most basic unit possible: the planck length, time, and mass, and consequently the planck energy and every other unit. Just find some arbitrary number by which to multiply the units to some practical range (something base-10 is obvious, but maybe there is some more mathematically profound multiple, like pi, which would be more useful), and you have an entire system of measurement.

On the contrary. We know that the Speed of light is not uniform and depends on the local condtions of the spacetime frame.

Besides, the effects of Gravity act with sppeds much faster than light.

Just last night John Baez (mentioned several other times in this thread) announced a potentially important breakthrough: a LQG calculation that derives the same value for a fundamental parameter as one based on classical assumptions. He calls it "tooth-gnashingly nerve-wracking exciting."

The problem with simplified articles as this one is that metaphores are used to explain theoretical physics to a broad audience. The interpretation here isn't new, it originated from Penrose' 1/2 spin networks. The abstracts by Fotini are related to the spin networks but are more about the properties of these networks then new claims about how we should interpret the universe. If you have fundamental problems with Penrose' view on his 1/2 spin networks, then I'd be happy to hear about them, but your argumentation until now does not yet support a remark regarding philosophy of physics 101.

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.

One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.

Of course there is also Markopoulou's recent expository article, which is a great introduction!

Maybe the folks at Scientific American just needed to find one person that they could write a nice story about. You could check out John Baez's web page too, or Dan Christensen's page for example.

I can think of a couple ways to use a black hole to generate power. Rotating black holes have huge amounts of kinetic energy, and such a hole that had an electric charge could be used as a huge generator, if we could get an electric field large enough to surround it.

The other method uses very small holes, about the size of a proton with the mass of a mountain. Due to Hawking radiation, such a hole would put out more power than a six nuclear power plants (if I remember the statistic).

Those wishing to learn more about Reverse Engineering software may find the following pages useful:

Fravia's pages - A huge, sprawling resource of RE information. Chances are, any info you need is in here somewhere. It's just a matter of finding it...

The Art of Assembly and other essential ASM programming links. If you want to learn RE, sooner or later you're going to have to learn assembly. Get to it.

Mammon's Tales to his Grandson and other useful RE classics by a G.O.M. of the genre. Oh, and an older mirror, possibly with extra/different stuff on it.

Google's directory listing for Disassemblers, which you'll be wanting at least one of...
...and the listing for Testing tools, which may come in handy.

Finally, Compuware's SoftIce page - SoftIce being the single most popular RE tool for Win32 software... Not that you're likely to be paying for it, you warez monkey, you.

Have fun, kids, and release Open Source.

(Posting Anon because I don't need the Karma or the implication of knowledge =)...