Gravitation Anomaly Measured 540
Rob Riggs writes "Is there a hole in Einstein's Theory of Relativity? A story in The Economist talks about an apparent gravitation anomaly recorded during solar eclipses. According to Chris Duif at the Delft University of Technology, the 'Allais effect' is real, unexplained, and could be linked to another anomaly involving a the Pioneer spacecraft. More detailed information can be found in the paper he has just posted on arXiv.org."
SUBSPACE !!! (Score:4, Funny)
Where is Capn' Picard when he is needed
Re:SUBSPACE !!! (Score:5, Funny)
Re:SUBSPACE !!! (Score:3, Funny)
Re:SUBSPACE !!! (Score:5, Funny)
Re:SUBSPACE !!! (Score:5, Funny)
We are the Bord.
Ennui will envelope you.
Existence is futile.
Re:SUBSPACE !!! (Score:3, Funny)
Gravitation Anomaly (Score:4, Funny)
Re:Gravitation Anomaly (Score:3, Funny)
"They swing lower because you are getting old, honey; not because of the ecli...*WHACK*
Anomaly in Gravity During Sun Eclipses? (Score:2, Insightful)
Re:Anomaly in Gravity During Sun Eclipses? (Score:4, Informative)
Re:Anomaly in Gravity During Sun Eclipses? (Score:4, Funny)
Re:Anomaly in Gravity During Sun Eclipses? (Score:3, Informative)
Apparently, you've never seen a scrabble word. (There are only two 'y's in Scrabble).
Re:Anomaly in Gravity During Sun Eclipses? (Score:3, Informative)
Syzygy wikipedia link (Score:3, Informative)
Wow, Syzygy [wikipedia.org] really is a word. Somehow, I don't remember that one from the decade-old high school science corner of my brain. That's almost as good as Xyzzy [wikipedia.org].
-jim
Re:Anomaly in Gravity During Sun Eclipses? (Score:2, Insightful)
Ironically, this was hailed as a proof of Einstein's relativity in the early 20th century, since the angle of deflection observed is much closer to the relativistic prediction, than to the Newtonian prediction.
bah, nevemind! (mod parent down) (Score:2)
That will teach me to not RTFA.
Re:newtonian prediction (Score:3, Informative)
Re:Anomaly in Gravity During Sun Eclipses? (Score:3, Informative)
Re:Anomaly in Gravity During Sun Eclipses? (Score:2)
That's what I get to, after RTFA. My original post was a joke, and I'm surprised it was modded Insightful.
Re:Anomaly in Gravity During Sun Eclipses? (Score:2, Interesting)
Nope, exactly the opposite.
Not to mention that the article suggests that the effect occurred just as the alignment took place, not slightly before or after, when the summed effects of the Sun and Moon's gravity should have been nearly the same as during the alignment.
Re:Anomaly in Gravity During Sun Eclipses? (Score:4, Insightful)
Why hasnt this effect, if it exists, been noticed 1000's of times?
Re:Anomaly in Gravity During Sun Eclipses? (Score:5, Interesting)
To answer your question, the effect, if it exists, hasn't been noticed because there are many other perturbing effects on the orbit. The most important, by decreasing magnitude, are: earth's gravitational attraction, moon attraction, oblateness of the earth (that is, the flattening at the poles), sun gravitational attraction, solar radiation pressure, tri-axiality of the earth (that is, the east-west irregularity in the gravitational attraction), albedo (that is, the pressure exerted by the sunlight reflected by the earth), dynamic solid tide (the gravitational effect of the earth's deformation caused by the moon's attraction), gravitational attraction by venus, gravitational attraction by jupiter, relativistic effects caused by the earth's gravitation.
So, you can see that there are so many other effects that it's pretty hard to separate each one. In particular, the effects of solar radiation and albedo change more or less randomly, so in the end, whatever cannot be explained otherwise in a satellite's orbit is normally attributed to "solar radiation".
It's only when a probe goes so far from the sun as Pluto that solar radiation becomes small enough for other perturbations to be measured.
The final frontier (Score:3, Funny)
Re:Anomaly in Gravity During Sun Eclipses? (Score:5, Interesting)
(one facing the object, and the other on the opposite side). These lead to diurnal (24 hour cycle) and semi-diurnal (12 hour cycle) tides.
When the Moon and Sun are aligned together, you have Spring tides. Neap tides are caused when th e Moon and Sun are perpendicular to one another. There is also the Proxigean Spring Tide, when the moon is at its closest point to the Earth (perigee). This time is known as the "proxigee", and causes even higher tides than ordinary Spring Tides. Fortunately, these only occur once every 1.5 years.
The gravitational acceleration at the Earth's surface is 9.8 metres/second per second (towards the centre of the Earth).
The gravitational acceleration on Earth due to the Sun is 0.0059 metres/second per second.
Or about 5.9 millimetres/second.
The gravitational acceleration on Earth due to the Moon is 0.000033 metres/second per second.
Or about 0.033 millimetres/second.
Source: Space Talk Forum [space-talk.com]
These amounts are small, but research groups at one of the particle accelerator rings actually noticed a distortion in the targeting of the beams due to the stretching/squashing of the surrounding land caused by the changing positions of the Sun and Moon. This caused the beam to periodically go off target.
Intuitively, one would assume that gravity would be less when the Sun and Moon were overhead, and the pendulum would swing slightly higher and slower. Plus the behavior of the pendulum should vary according to the positions of the Sun and Moon.
If the "shielding effect" occurred with large objects, then it would also apply to Earth's ocean tides. The closest side of the Earth one should shield the opposite side, but the bulging effect can be explained by simple vector addition/subtraction [uoregon.edu].
Re:Anomaly in Gravity During Sun Eclipses? (Score:3, Informative)
There's a much easier way. It only takes around 50 people to make a large office block sway. All they have to do is push on opposite sides at the right rate and they can use the resonant frequency of the building to build up amplitude.
Alternatively, you can do what Tesla did, and attach a Tesla oscillator onto one of the iron beams o
Re:Anomaly in Gravity During Sun Eclipses? (Score:3, Interesting)
No such thing (Score:4, Funny)
Re:No such thing (Score:5, Funny)
What we call light bulbs are truly dark suckers as well. That is why light bulbs are hot, just like the Sun. When a light bulb is full of dark and won't suck dark any more, it cools off. If you look in old light bulbs you can even seen the accumulation of dark.
Dark is also heavier than water. This can be seen in the oceans where the deeper you go the darker it gets.
Re:No such thing (Score:3, Funny)
Re:Speed of Dark (Score:5, Funny)
Re:No such thing (Score:3, Funny)
The Darksucker Theory (Score:5, Funny)
Electric bulbs don't emit light; they suck dark. Thus, we call these bulbs Dark Suckers.
The Dark Sucker Theory and the existence of dark suckers prove that dark has mass and is heavier than light.
First, the basis of the Dark Sucker Theory is that electric bulbs suck dark. For example, take the Dark Sucker in the room you are in. There is much less dark right next to it than there is elsewhere. The larger the Dark Sucker, the greater its capacity to suck dark. Dark Suckers in the parking lot have a much greater capacity to suck dark than the ones in this room.
So with all things, Dark Suckers don't last forever. Once they are full of dark, they can no longer suck. This is proven by the dark spot on a full Dark Sucker.
A candle is a primitive Dark Sucker. A new candle has a white wick. You can see that after the first use, the wick turns black, representing all the dark that has been sucked into it. If you put a pencil next to the wick of an operating candle, it will turn black. This is because it got in the way of the dark flowing into the candle. One of the disadvantages of these primitive Dark Suckers is their limited range.
There are also portable Dark Suckers. In these, the bulbs can't handle all the dark by themselves and must be aided by a Dark Storage Unit. When the Dark Storage Unit is full, it must be either emptied or replaced before the portable Dark Sucker can operate again.
Dark has mass. When dark goes into a Dark Sucker, friction from the mass generates heat. Thus, it is not wise to touch an operating Dark Sucker. Candles present a special problem as the mass must travel into a solid wick instead of through clear glass. This generates a great amount of heat and therefore it's not wise to touch an operating candle.
Also, dark is heavier than light. If you were to swim just below the surface of the lake, you would see a lot of light. If you were to slowly swim deeper and deeper, you would notice it getting darker and darker. When you get really deep, you would be in total darkness. This is because the heavier dark sinks to the bottom of the lake and the lighter light floats at the top. The is why it is called light.
Finally, we must prove that dark is faster than light. If you were to stand in a lit room in front of a closed, dark closet, and slowly opened the closet door, you would see the light slowly enter the closet. But since dark is so fast, you would not be able to see the dark leave the closet.
Next time you see an electric bulb, remember that it is a Dark Sucker.
Re:The Darksucker Theory (Score:3, Informative)
Re:The Darksucker Theory (Score:3, Funny)
Not everyone is laughing (Score:3, Informative)
From their perspective, gravity should not be seen as a force field but rather as the cummulative effect of all massive bodies continuously absorbing/dissipating Æther. Locally the earth sucks most of the Æther and we experience the
3rd body problem? (Score:5, Interesting)
Re:3rd body problem? (Score:3, Interesting)
Nevertheless, for solar system dynamics, this is irrelevant. Newtonian gravity works quite well, and even if you did need to go to relativistic corrections, you can do that within the perturbation scheme of linearized gravity to more than sufficient accuracy.
Re:3rd body problem? (Score:2, Interesting)
Re:3rd body problem? (Score:3, Interesting)
Re:3rd body problem? (Score:3, Funny)
Re:3rd body problem? (Score:4, Funny)
Re:3rd body problem? (Score:3, Interesting)
On the other hand, you can calculate a solution to the three-body problem to any level of accuracy that you are interested in, without much effort. Yes, it's an approximation, but so is any calculation.
Thad
Re:3rd body problem? (Score:3, Interesting)
Re:3rd body problem? (Score:5, Informative)
Instead, iterative solutions are used: given the current masses, positions, and velocities of the objects involved, figure out where they'll be a short time from now. Lather, rinse, repeat. The problem with this is that over long timespans (tens of millions of years), errors build up.
3rd body very much a problem (Score:5, Funny)
Re:3rd body very much a problem (Score:4, Funny)
Well an analytical closed-form solution might not be possible, but iteration will surely help.
Re:3rd body problem? (Score:5, Insightful)
Re:3rd body problem? (Score:5, Funny)
The Economist? (Score:5, Insightful)
Re:The Economist? (Score:5, Funny)
Re:The Economist? (Score:5, Insightful)
Which in my mind only casts doubt on its existance.
Indeed. An economist making a valuable contribution to science ... that's almost as absurd as, oh, I don't know, a patent clerk making a valuable contribution to science.
Re: The Economist? (Score:2)
> Why is this being carried in the Economist? Shouldn't it be picked up by New Scientist or some other scientific (or pseudo-scientific) publication?
FWIW, this is really old news. The others have probably already covered it.
Re:The Economist? (Score:5, Informative)
They know it too, and consequently it is very hard to find much of a discount on subscription pricing -- if you can pick it up for under $100/yr you are doing very well. All those other rags can typically be found for pennies on the dollar if you look.
In case you can't tell, I get all my news online - no tv news, no newspaper, maybe a dab of NPR when I'm tired of listening to my music in the car and no magazines, except the Economist. Which I get full access to online by virtue of paying for a paper subscription.
Re:The Economist? (Score:5, Informative)
And no I don't work for them.
so called paraconical pendula (Score:5, Funny)
Mr. President, we must spend whatever is necessary to close the paraconical pendula gap.
Einstein would not be surprised (Score:5, Interesting)
Testing theories is a very thankless task, because nature never says "yes." Usually nature says "no," meaning that a measurement contradicts a theories predictions.
Sometimes, nature says, "maybe," indicating that while the measurements are consistent with the theory.
But nature never says "yes," because your theory could be incomplete or erroneous but your instruments are either too inaccurate to detect the error, or you are not doing the right experiment.
Newtonian dynamics makes good enough predictions for alot of phenomena.
General Relativity is more precise in its predictions.
Given our difficulties in unifying it with quantum mechanics, it is likely that we don't have the right theory. As our instruments get more precise and we conduct more experiments, eentually we'll get a hint as to where we are going wrong.
Re:Einstein would not be surprised (Score:5, Insightful)
Good reason for a mission to the Moon (Score:5, Interesting)
For real confirmation, an experiment on one of the Jovian moons would do nicely.
Yes, I'm serious about this. This is fundamental to our understanding of physics, which is in turn fundamental to our understanding of the origins, processes and fate of the universe. A billion to put a pendulum on the Moon would be money well spent.
Re:Good reason for a mission to the Moon (Score:3, Insightful)
Or, you could just do the test here on earth at night. Then the whole mass of the earth is between your apparatus and the sun.
I guess the reason that doesn't work is that thermal effects (like those that may be causing the Allais results) change everything at night, and it's too hard to distinguish a legitimate anomaly from some-thermal-effect-we-didn't-think-of.
Still, there's no need to go to Jupiter or even the moon; as a satellite in a higher and higher earth orbit checks the effect, the earth effects
If gravity is blocked by mass, then... (Score:5, Insightful)
Re:If gravity is blocked by mass, then... (Score:5, Interesting)
I see no discussion in the article of the fact that the moon distorts the space around it so that when it is between us and the sun we are slightly further away from the sun than when it is not in line. This effect has to be incredibly small but it appears the allais effect, if it exists at all, is quite small, so perhaps this is the cause. Somebody should at least calculate it out.
I have seen this theory that they mention about gravity being less effective when weak. The usually more reliable Scientific American allowed an article on it to sneak in some months ago.
Its a very silly idea because it breaks the principle of equivalence - you can now tell if you are in an elevator or a gravitational field by bringing a mass close to a test mass to almost cancel out the field and observing whether or not you see the weak gravity effect.
This in turn means physics is not covariant and that there are preferred frames of reference. So its not a "small adjustment" but a total do-over of physics.
Re:If gravity is blocked by mass, then... (Score:3, Interesting)
With sufficiantly accurate measurment devices (which we don't happen to have), you should be able to tell the difference between an elevator or a gravitational field anyways. Why? Gravity is a field. Therefore the force at your head is eve
Re:Good reason for a mission to the Moon (Score:5, Funny)
This is a total waste; the Republicans already know the origins of the universe. It's all written in the book of Genesis. The earth was created 6000 years ago, in 7 days. That billion dollars would be better spent on more military hardware for use in the US's next invasion, or better yet it could be given in a no-bid contract to Halliburton for some massively overpriced fuel and services.
Recursive Reality (Score:2)
Gravity Probe B (Score:5, Informative)
(Side note-- I never heard of this probe until I saw it in a magazine. Why not?)
Possible explanation (Score:4, Interesting)
Could this be constructive interference caused by the collision of the gravity wavefronts from the sun and the moon when they are lined up just right?
Just a thought, the real explanation is probably much crazier.
From Chris Duif's paper: (Score:5, Interesting)
And here's a point not covered in the paper: if these experimental effects occur when the moon is between the pendulum and the sun, then shouldn't they also occur every time the earth is between the pendulum and the sun...say, every night? If this effect is due to a large mass's ability to block gravity, then surely someone should have detected this effect from the earth blocking the sun's gravity by now!
On the other hand, if the effect is because moon cheese acts as a form of Cavorite [wikipedia.org], well, then I can't help you with that.
Re:From Chris Duif's paper: (Score:4, Insightful)
Problem is, there is a known effect that would change the gravitation acceleration on an object as the Earth's orientation changes with respect to the sun. During the lunar eclipse, though, there's very little change in the relative positions and orientation of the earth, the moon and the sun.
That is, I suspect it would be too hard to distinguish between any such Allias Effect from the Earth and solar (and in this case, lunar) tides.
Re:From Chris Duif's paper: (Score:3, Informative)
I've read many of the old (and new) 'push' gravity theories, the ones that theorize a particle carrier for gravity (I'll call them gravitons here). Where there are less gravitons, e.g. next to a body and more so between two bodies), you experience a lop-sided 'push' from areas of high graviton density.
With two bodies, you wouldn't be able to tell the difference - the absorption of gravitons would be measurable as
A reminder (Score:5, Informative)
Analytical solutions only exist for two cases: the overall case that describes a homogeneous universe, and the Schwartzschild case that describes a spherical body. There is also a linear approximation that gets gravity waves.
It's a bit premature to say that GR has a hole in it, because nobody has ever explored it fully. Perhaps this will lead to a solution of GR for this case, or perhaps not.
Re:A reminder (Score:3, Funny)
Another reminder (Score:3, Interesting)
Mys-TEER-i-ous things (with waggling fingers)...
Re:A reminder (Score:3, Informative)
who knows, I think the only way you could say GR has a hole in it is because it doesn't seem to mesh well with quantum mech. Though I'm not sure if it would actually take hundreds of pages to write out the GR equations, I'm sure that back when it was first done, there were great ways to make it shorter(I've seen a few and I hate them, damnable tensors and other things that find their way into EM books).
The simplest way to write out the GR equations takes only a line. It's incredibly beautiful but usel
I knew it was a powerful IDE but ... (Score:4, Funny)
If gravity is blocked by mass. (Score:4, Insightful)
The earth would block much more solar gravity than the puny little moon.
Then again, we would need a pendulum which is attracted to solar gravity because every pendulum on earth which swings, is doing so because of the gravitational attraction of the Earth.
Pay attention... pendulums on earth fall towards the EARTH, NOT THE SUN.
And another thing:
if you allow a pendulum to swing freely for 24 hours, the reason its path will trace out a circle, is *because of inertia* and the earth is rotating. THE PENDULUM IS NOT SWINGING TOWARDS THE SUN'S GRAVITATIONAL FIELD.
Are there any economists here who can explain this more clearly?
Re:If gravity is blocked by mass. (Score:3, Informative)
Like hell they don't. The sun is the most massive hunk of anything in the star system and its gravity, by definition, has an effect on everything. Accurately measure the period of that pendulum and you will find that it has a tendency to move faster during the night (earth and sun pulling in the same direction) as it does during the day (earth and sun pulling in opposite directions). The question this anomally brings up is how mu
Proper peer review (Score:5, Informative)
Gravitational Anomalies in Greece (Score:4, Interesting)
For example, you put your car in neutral in the outskirts of the mountain and instead of gravity to pull it down, it is tractored upside. Expert physicists claim there is another energy in the mountain area that is more powerful than the gravity itself, thus creating the effect.
NATO was interested (and presumambly is still) in that particular area. It's part of Greece's x-files
Re:Gravitational Anomalies in Greece (Score:3, Insightful)
Who mods this crap up? "NATO was interested" and "gravitational anomalies"?!? WTF!? I thought we were nerds here...
"Gravity hills" are nothing more than optical illusions, Penteli mountain included. Check out this link [ucr.edu] for more information. (shakes head at the state of "science" here on Slashdot... double shakes at the tin foil hat wearing mods...)
Einstein is safe (Score:5, Interesting)
Seems to me like the effect is most likely due to someone walking their dog a couple blocks away.
More interesting is how everyone wants to prove that Einstein's theory is wrong. Seems to me like a bit of brain-envy.
Nice try, but this article only goes about 0.5*10^-10 of the way to convincing me the chuck the field equations.
Because when you think Advanced Particle Physics (Score:3, Funny)
Not shielding, a new horizontal force possibly. (Score:3, Interesting)
Most of the posts are supposing the physicists doing this are real dumb. That in itself, is stupid. I think one or two have interesting points (e.g. "Einstein is Saf e") and most of the others are way off base. The paper is a summary of research by other people. The problem being discussed was noticed by Allais 50 years ago when he ran a month long pendulum experiment (three drops per minute I believe) that happened to intersect the time of an eclipse. The paper goes over a number of possible reasons for error and includes some as yet unpublished data on experiments intended to uncover them. The possibilities are c reative and followed up scientifically, for example one is done in remote China with nobody within 200 meters. All tests showed the suggested errors to be miniscule, although the paper does suggest that a combination of them might just cover it.
It would appear that a significant anomaly has been detected by various experiments and that professional scientists are taking it much more seriously than say cold fusion. It also is clear that there is a lot still to learn about gravity and that NASA is one of the groups that is working hard to figure out why its space probes don't move as expected. Some people even think gravity moves 20 times faster than light and other stories. It is not a shut case yet. In the paper mentioned in the post, they are saying that most people couldn't in the past solve the problem because they were thinking in terms of the Moon "shielding" the Earth from gravity, which the paper does not believe. They think it is more like an extra horizontal force that sometimes occurs during eclipses (of which there are different kinds including variations of angles). So all the posts about shielding are off base.
NASA has suggested that if experimental error really can't be the culprit, it might be caused by the same thing that apparently is accelerating Voyager more than expected.
I'd like to quote from a NASA article on the people who built Gravity Probe B [gravityprobeb.com].
I think that is cool. It says to me we have a good chance about learning a lot more about gravity and lots of other fundamental physics in the near to medium term future.
The paper also notes that one more individual experiment will not solve it; many simultaneous and comprehensive experiements are needed over the next few eclipses. It also suggests that it might be interesting to investigate "gravitational lensing by relativistic dark matter" although I cannot tell if that suggests we are in the midst of a river of high speed dark matter or what, something invisible passing between the Earth and Moon? Somebody with astrophysics degree please finally step in. Sounds like it might be interesting to have the ISS get involved too!
Links:
NASA decrypting the eclipse ('99) [nasa.gov]
Gravitational Anomalies - Literature List [space-time.info]
In Search of Gravitomagnetism (NASA Gravity Probe B) [nasa.gov]
Re:Solar Eclipses (Score:5, Informative)
I would highly doubt that Einstein's theory is flawed, but then again, they did not study the effects of gravity during a solar eclipse back then.
Not only is this comment not "insightful" but it is just plain wrong. One of the original PROOFS for relativity involved measuring the amount that light is bent during a -- pay attention now -- solar eclipse. To quote the article you so carefully did not read, it was "observations taken during a solar eclipse (of the way that light is bent when it passes close to the sun) which established General Relativity in the first place."
Next.
Re:Solar Eclipses (Score:2)
Wasn't Newtonian physics good enough for a long time? No doubt someday we'll get something that replaces Relativity, or more accurately, refines it to explain those small observed differences. That's not a bad thing; indeed, just as relativity opened up all kinds of new applications such as nuclear power, a more precise understanding of the universe could give us untold new power.
(Note: by "us,"
Re:I'm no rocket scientist, BUT...... (Score:2)
One would assume that during a solar eclipse, the serial effect of the sun and moon's gravity would reduce the felt gravity on earth. With a lower gravitational acceleration, I think the pendulum should slow down, and not speed up. Of course when Allais (sp?) made his observation, there may have been something else acting on the pendulum coincident to the eclipse.
Re:One possible explanation (Score:5, Informative)
They don't. They do have momentum though.
Re:One possible explanation (Score:2)
Re:One possible explanation (Score:5, Informative)
Re:One possible explanation (Score:3, Informative)
Photons are both influenced by gravity, and can influence gravity.
To understand how they are influenced by gravity, one must understand that according to general relativity, spacetime is curved, and bodies follow paths called geodesics which are paths of minimal distance. (Geodesics on a spherical surface, for exa
Re:One possible explanation (Score:5, Interesting)
As I recall, MOND solves some of the more annoying problems of astronomy: missing matter, and the apparent need for a period of faster-than-light expansion early in the history of the universe.
Re:One possible explanation (Score:5, Informative)
As for the "apparent need" for FTL expansion in the early universe, by which I assume you mean inflation, some very specific predictions of inflation are now verified by WMAP [nasa.gov], including the structure of the acoustic peaks in the CMBR angular power spectrum.
Wacky as they may seem, dark matter, dark energy, and inflation are the mainstream theories right now for a reason: the alternatives so far simply don't work as well.
Re:One possible explanation (Score:4, Funny)
Given: Photons are quantized light
Given: Light travels at c
Given: No massive particle can travel at or faster than c
Given: c is defined as the speed of light in a vaccuum
Postulated: Photons have mass
Therefore: Light has mass, as it consists of massive particles
Therefore: Light cannot travel at or faster than c
Therefore: The speed of light is less than c.
Therefore: c is less than c
ERROR: STACK OVERFLOW
Re:One possible explanation (Score:3, Informative)
It is. You can get a very slight boost in the speed of light by suppressing quantum vacuum fluctuations (the Casimir effect).
Nope... (Score:3)
Sorry, no - Casimir effect has nothing to do with C.
The Casimir effect is a measurable attractive force (really a repellant force from the opposite sides) between two parallel plates that are very close together.
According to QED, there is no absolute zero-energy vacuum - all space, no matter how empty, has energy that spontaneously forms particle/antiparticle pairs that pretty quickly an
Re:Nope... (Score:3, Interesting)
Google it. [google.com]
As I'm sure you know, even in a pure zero-energy vaccum space is not empty. The vacuum is actually filled with a seething sea of vacuum fluctuations and virtual particles. In between conducting plates the Casimir effect supresses some of those vacuum fluctu
Re:One possible explanation (Score:5, Funny)
Re:and then there's this (Score:2)
Re:In other news... (Score:2, Funny)
Too easy, give me another..
I know! (Score:2)
This one made my BRAIN HURT:
The Allais effect is a small additional acceleration, so tiny that it would take an apple about a day to fall from a tree branch if it were the only gravitational effect around.
Does this make sense to anyone? An effect having a physical size? That's like saying "I ran about a gravity yesterday, man I was tired."
Re:I know! (Score:3, Insightful)
All they're saying is that if 'g' were of the magnitude of this effect, then it would take a day for an apple to fall from a tree.
d=0.5*g*t^2
Pick a reasonable height for a tree, use 1 day for t, and solve for g.
Roughly, we're talking about something on the order of 10e-9 m/s^2