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Newton's Second Law, Revisited

Zonk posted more than 6 years ago | from the my-favorite-law dept.

Education 171

eldavojohn writes "Dust off your fundamental physics books, an aspiring astrophysicist by the name of Alex Ignatiev has published a paper that proposes testing special cases of Newton's Second Law on earth's surface. His goal is sort of ambitious. The time he has to test his theory is only 1/1000th of a second, twice each year, in either Greenland or Antarctica. What would he look for? Spontaneous motion. From his interview with PhysOrg: 'If these experiments were to take place, Ignatiev says that scientists would look for what he calls the SHLEM effect. This acronym stands for static high latitude equinox modified inertia and would be noticed in a condition where the forces of the earth's rotation on its axis, and of the orbital force of the earth as it moves around the sun, would be canceled out ... In the end, if Newton's Second Law could be violated, he would be forcing physicists to reevaluate much of what we understand derived from that law — which is quite a bit.'"

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A bit early for April Fools? (5, Interesting)

lecithin (745575) | more than 6 years ago | (#18552999)

Or is it?

Reminds me of what Patrick Moore did:

Stolen from

http://en.wikipedia.org/wiki/Patrick_Moore [wikipedia.org]

Eccentric personality

Due to his long-running television and xylophone playing career, eccentric manner, distinctively rapid speech delivery and in later years his ever-present monocle, Moore is widely-recognised and well-respected in the United Kingdom, even by those with no interest in astronomy. This was used to great advantage for a 1976 April Fool's joke on BBC Radio 2, when Moore announced that at 9.47 am a once-in-a-lifetime astronomical event was going to occur: Pluto would pass behind Jupiter, temporarily causing a gravitational alignment that would reduce the Earth's own gravity. Moore informed listeners that if they could jump at the exact moment that this event occurred, they would experience a temporary floating sensation. The BBC later received hundreds of phone calls from listeners claiming to have felt the sensation.

Moore joined the Flat Earth Society as an ironic joke though many have taken this seriously.

MOD THE TROLL DOWN!!! (-1, Troll)

Anonymous Coward | more than 6 years ago | (#18553009)

MOD THE TROLL DOWN!!!

Re:MOD THE TROLL DOWN!!! (5, Funny)

Anonymous Coward | more than 6 years ago | (#18553493)

Done.

Re:A bit early for April Fools? (0)

Anonymous Coward | more than 6 years ago | (#18553297)

Everybody now!

Patrick Moore plays the xylophone
Patrick Moore plays the xylophone
Patrick Moore plays the xylophone
Pa-Pa-PaPaPaPat-rick!

Re:A bit early for April Fools? - Already proved.. (0)

Anonymous Coward | more than 6 years ago | (#18554413)

...by the rocks that move in the desert...

http://mmmgroup.altervista.org/e-rocks.html [altervista.org]

Re:A bit early for April Fools? (1)

Poltras (680608) | more than 6 years ago | (#18554517)

I certainly fail to see what Patrick Moore has to do with this issue... Nice Markov though.

No exceptions (5, Funny)

edwardpickman (965122) | more than 6 years ago | (#18553005)

Law breakers should be punished to the fullest extent of the physical law.

MOD THE TROLL DOWN!!! (-1, Troll)

Anonymous Coward | more than 6 years ago | (#18553049)

MOD THE TROLL DOWN!!!

Re:No exceptions (1)

orkysoft (93727) | more than 6 years ago | (#18553061)

It doesn't look like they're going to settle...

Hammer, Feather, Freefall on the Moon: Revisited (5, Interesting)

Anonymous Coward | more than 6 years ago | (#18553139)

"Fall heavy towards the moon, and the moon falls also towards you." -- Nietzsche

Hammer and feather are dropped simultaneously from equal heights (as measured by distance from the center of the moon), separated laterally by a distance substantially less than the moon's diameter. Both hammer and feather experience force from the moon's gravity proportional to their mass, and hence both accelerate at the same rate. Meanwhile, the moon is also accelerating towards the other two objects, but unevenly so: the hammer exerts a greater gravitational pull due to its greater mass. The moon is therefore subject to a torque, causing it to accelerate more rapidly towards the hammer.

The hammer is first to hit the ground.

Anyone who denies this truth is a spatially absolutist lunocentric whose refusal to recognize the validity of hammer/feather mechanics places him wholly beyond the help of Galilean metaphysics. Such hammer/feather rejectionists ought to be banished from planetary space, for their own good and for the good of not only hammers and feathers but all subjugated smaller objects, everywhere, who find themselves victims of this scientifically perpetrated emassculation.

--
a756f345ec354225c08ff1a10a43162a

Re:Hammer, Feather, Freefall on the Moon: Revisite (0)

Anonymous Coward | more than 6 years ago | (#18553303)

Suppose the hammer and the feather were dropped in superposition along the same axis. They would both hit the moon at the same time.

Re:Hammer, Feather, Freefall on the Moon: Revisite (1)

Whiteox (919863) | more than 6 years ago | (#18553473)

Ever hear of Force Vectors?
The moon would be pulled towards both objects at the same rate.

Re:Hammer, Feather, Freefall on the Moon: Revisite (0)

Anonymous Coward | more than 6 years ago | (#18553517)

The force pulling the moon towards the hammer is greater than the force pulling the moon towards the feather, as each one's gravitational force is proportional to the height of the object. Therefore (unless F=ma is no longer an accurate law, couldn't figure out TFA) the acceleration towards each will be that force divided by the moon's mass, and obviously the acceleration towards the hammer will be much higher, meaning the mon and hammer will collide sooner than the moon and feather.

Re:Hammer, Feather, Freefall on the Moon: Revisite (1)

zippthorne (748122) | more than 6 years ago | (#18554061)

You could do this as a 3-body problem, and then you'd be correct that they fall at different rates, but you'd have quite a difficulty measuring the difference, since the feather and the hammer are orders of magnitude of orders of magnitude less than the mass of the moon.

The other point you've mentioned is actually quite the physical puzzle. There's no reason why gravitational mass and inertial mass need to be the same, yet to our ability to measure so far, they are.

I KNEW IT (0, Offtopic)

heptapod (243146) | more than 6 years ago | (#18553029)

Spending $1000 on these plans for the Dean drive weren't a waste of my money! Take that science!

Re:I KNEW IT (0)

Anonymous Coward | more than 6 years ago | (#18553195)

OH MY SCIENCE!

I often wonder about (1)

Nybble's Byte (321886) | more than 6 years ago | (#18553067)

who formulated Cole's Law, especially when eating ribs.

violate what law? (1)

Chris Chiasson (908287) | more than 6 years ago | (#18553069)

So, what law is this person using to calculate the cancellation of the forces?

Re:violate what law? (5, Informative)

demeteloaf (865003) | more than 6 years ago | (#18553161)

Currently, there is a discrepancy between the rotations of galaxies, and what newtons law says should happen. If you look at large galaxies, at a bunch of different radii, all the stars orbits are at about a constant orbital velocity, which since there is less force acting on them from gravity, shouldn't happen.

The most common physical explanation of why this happens is that there is a ring of dark matter around the galaxies that is also producing a gravitational force, and that when you add in the force from the dark matter, the equations work out, and you calculate that the orbital velocities should be constant.

However, there are some physicists who don't like the idea of dark matter, and in order to explain how galaxies orbit, introduced a new version of newton's second law. F = m * f(a/a0)*a, where a0 is a new fundamental constant describing a small acceleration level where these new Newtonian dynamics hold. and f(x) is a function that equals x when x > 1. This theory describes the constant angular orbit speed of galaxies without the need for the existence of dark matter, however, the theory has problems when applied to relativistic systems.

What it looks like this new paper proposes to do is find a place on earth where the acceleration from the coriolis effect, the centripital acceleration and the acceleration from the sun will all cancel out, and then create a really small force and see if the modified second law works for a very small absolute acceleration.

Re:violate what law? (1)

GryMor (88799) | more than 6 years ago | (#18553495)

Uhmm... what acceleration from the sun? Or does this hypothosis thats attacking Newton forget that Newton allready fell to GR? How would this not be dominated by the 1g acceleration of the ground pushing up on you?

Re:violate what law? (1)

loganrapp (975327) | more than 6 years ago | (#18553671)

What it looks like this new paper proposes to do is find a place on earth where the acceleration from the coriolis effect


Everyone knows it's the cornwallis [youtube.com] effect. Pfft.

Re:violate what law? (1)

zero_offset (200586) | more than 6 years ago | (#18555053)

Bah. Everyone knows it's really the clanwallace [akamai.net] effect.

Re:violate what law? (1)

Plutonite (999141) | more than 6 years ago | (#18554165)

an interesting question to ask would be: even if the said forces "cancel out" in a particular coordinate plane somewhere on earth, forces acting in directions other than those considered(e.g gravitational curvature) would interfere with his oh-so-delicate measurements, no? Indeed, it would seem a NASA investigation during a space-mission would be even better, but I think it would be hard to convince NASA to get it's astronauts to do a 10-min off-course acceleration with a shuttle in some pointless direction, all for the love of science. Oh well.

Re:violate what law? (1)

Mateo_LeFou (859634) | more than 6 years ago | (#18554333)

"forces acting in directions other than those considered(e.g gravitational curvature) would interfere with his oh-so-delicate measurements, no?"

Well, yeah, but as I understand it their order of magnitude would be such that measurements would remain meaningful, which is not the case when the major nearby forces are acting on the system.

Finding holes in the theory... (4, Interesting)

RyanFenton (230700) | more than 6 years ago | (#18553081)

Yes, it only takes one demonstration to a render invalid a scientific theory. But that does not validate any other theories by doing so, unless they can accurately carry the same predictive weight as the previous theory, plus comply with the improved observations.

A hole in Newtons second theory in any case doesn't mean scientists throw out their physics books, it generally means they add and exception to the theory and work on finding a more unified algorithm to describe the newly revised observations. Here's hoping this somewhat exotic set of observations leads eventually to a stronger set of theories, rather than just more false controversy about 'mavericks' and 'closed minded skeptics' - everyone's a skeptic AND a maverick, closed minded and radical - focusing only on the extremes of that, especially in terms of science sort of ignores the whole point of science, to use biased viewpoints to paint a larger picture.

Ryan Fenton

troll toolbox (1, Insightful)

Anonymous Coward | more than 6 years ago | (#18553301)

Template #183
Category: Instant karma
For: new scientific theory proposed

Yes, it only takes one demonstration to a render invalid a scientific theory. But that does not validate any other theories by doing so, unless they can accurately carry the same predictive weight as the previous theory, plus comply with the improved observations.

A hole in $SCIENTIFIC_THEORY in any case doesn't mean scientists throw out their $SCIENTIFIC_FIELD books, it generally means they add and exception to the theory and work on finding a more unified algorithm to describe the newly revised observations. Here's hoping this somewhat exotic set of observations leads eventually to a stronger set of theories, rather than just more false controversy about 'mavericks' and 'closed minded skeptics' - everyone's a skeptic AND a maverick, closed minded and radical - focusing only on the extremes of that, especially in terms of science sort of ignores the whole point of science, to use biased viewpoints to paint a larger picture.

Re:troll toolbox (0)

Anonymous Coward | more than 6 years ago | (#18553815)

I love you.

Re:Finding holes in the theory... (1, Insightful)

Anonymous Coward | more than 6 years ago | (#18555291)

Actually, even 1 failed experiment probably won't invalidate a theory - I'm fairly certain you'd have to demonstrate that the failure is repeatable given certain conditions. Otherwise there's no guarantee that you're equipment wasn't measuring properly or whatnot.

LIES! (1)

smthngcrprt726 (994828) | more than 6 years ago | (#18553093)

i always had a sneaking suspicion that my physics textbook was wrong... and now the funny thought is what if this somehow magically is correct... then can i light my textbook on fire because it will all be wrong and we'll have to start over from scratch?

the era precision cosmology (4, Interesting)

bcrowell (177657) | more than 6 years ago | (#18553097)

I think it's odd that MOND's enthusiasts are so eager to push it as an alternative to dark matter, now that we've entered the era of high-precision cosmology. We know a hell of a lot about cosmology that we didn't know ten years ago. We know the age of the universe to two significant figures. We know that the universe is expanding at an increasing rate. We know the spectrum and angular distribution of the cosmic microwave background to high precision. We've found out that neutrinos have mass. I can see how MOND would have some appeal back in 1981, when it was first proposed, but so much has changed in the last 26 years. The evidence has accumulated that we live in a universe that's much stranger than we'd believed. I think that's cool.

Re:the era precision cosmology (2, Insightful)

amRadioHed (463061) | more than 6 years ago | (#18553167)

The evidence has accumulated that we live in a universe that's much stranger than we'd believed. I think that's cool.
And what about that rules out MOND?

Re:the era precision cosmology (4, Informative)

bcrowell (177657) | more than 6 years ago | (#18553185)

And what about that rules out MOND?
It doesn't rule out MOND, but it shows that what MOND was trying to avoid -- dark matter -- is an intrinsic part of an extremely successful cosmological model, which has passed a variety of high-precision tests. The Wikipedia article on MOND [wikipedia.org] also discusses some empirical tests that MOND (and TeVeS) seems to have failed.

Re:the era precision cosmology (1)

friedman101 (618627) | more than 6 years ago | (#18553319)

We know the age of the universe to two significant figures.

Eh, I know the number of animals on earth to about 1 significant figure. (~1 googol)

I disagree (2, Insightful)

khallow (566160) | more than 6 years ago | (#18554451)

We know the spectrum and angular distribution of the cosmic microwave background to high precision.

This is the only statement that is correct since it is the only conclusion derived directly from observation. A lot depends on how accurate our models of the universe and physics are. I think MOND is unlikely to last, but the theory is yet viable. Your claims about the age of the universe, mass of neutrino, etc are likely to be correct, but it would be embarrassing if these observations turn out to be dependent on assumptions that are incorrect. Eg, perhaps Type IA supernovas are different in the early universe than they are now (even though physical law is the same, there are substantial differences like elemental composition), perhaps we're incorrect about our local gravity environment (eg, we're deeper in a gravity well) and this effects our perception of the temperature of the cosmic background, or perhaps a more accurate model of the universe involves oscillating yet massless neutrinos.

Laws should be brok... err, de-law'd (4, Funny)

Essequemodeia (1030028) | more than 6 years ago | (#18553169)

Maybe he's wrong, maybe he's not right. But damned if I don't admire a scientist who is willing to destroy a potentially promising career over a tiny hunch. Maybe god will take pity and alter gravity for just such an instance. I think he's getting bored with Iraq.

Re:Laws should be brok... err, de-law'd (0)

Anonymous Coward | more than 6 years ago | (#18554487)

It shouldn't destroy his career. Many scientists work on fairly "out there" stuff, braneworlds in higher dimensions and string theory spring to mind. What he's doing is good science, testing a hypothesis, and it shouldn't cause him any real trouble - he might find it harder to get a job because there aren't many research groups he'd fit into, but he's now slightly famous which always helps...

This is actually a well known phenomenon (1, Informative)

Anonymous Coward | more than 6 years ago | (#18553201)

http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/cr ls.rxml [uiuc.edu]

The link above explains the Coriolis force. Among other things, this is the force that causes water to spiral down the drain in different directions on different sides of the equator. It also manifests itself such that if you fly at sufficient speed travelling past 63 deg. North Latitude, you will feel a slight bump. This is easily measured and confirmed by placing an accelerometer on the aircraft. There is almost always a slight acceleration. Of course, the accelerometer is subject to the vibration of the aircraft and to rapid changes in altitude due to air currents so the bump is often lost in the noise floor but it's there nevertheless.

The phenomenon cited above is not limited to any particular time and is somewhat south of 80 deg. North Latitude but I suspect that Ignatiev is probably talking about the same thing. He should check his math.

Re:This is actually a well known phenomenon (1)

Alex Belits (437) | more than 6 years ago | (#18554325)

No. Coriolis force exists. Phenomena you have mentioned don't.

You almost got it (0)

Anonymous Coward | more than 6 years ago | (#18554977)

"No. Coriolis force exists."

More accurately: No coriolis force exists

The coriolis force is a fiction which describes the deflection of objects relative to the surface of the earth. In that regard, it's much like centrifical force.

http://www.worldwidewords.org/qa/qa-cen1.htm [worldwidewords.org]

In any event, I'm reasonably certain that you haven't flown north of the tree line with a pilot sufficiently experienced to point out the bump. When it is pointed out to them, most people do notice it. The next thing will be that you try to tell us that you can't hear the aurora borealis.

http://serendip.brynmawr.edu/biology/b103/f00/web3 /gallagher3.html [brynmawr.edu]

Anyway, the grandfather post is just as accurate as the article to which it was posted.

Re:This is actually a well known phenomenon (1)

julesh (229690) | more than 6 years ago | (#18554965)

The link above explains the Coriolis force. Among other things, this is the force that causes water to spiral down the drain in different directions on different sides of the equator.

Erm, yes. But the Coriolis force (actually not a force at all, but an effect of inertia in an accelerating reference frame) is (a) perfectly consistent with newton's second law, (b) not what the author of the paper, which you clearly didn't even look at the abstract of, was talking about and (c) doesn't cause water to spiral down the drain in different directions in different hemispheres, unless you can somehow produce a bowl of water with virtually zero angular momentum to start with (hint: you can't).

Well actually ... (0)

Anonymous Coward | more than 6 years ago | (#18555117)

My post was just as accurate as the story.

The confluence of circumstances (velocity, acceleration), that occur at 80 deg. N twice a year for 1/1000 of a second, could be reproduced anywhere on the surface of the earth.

A big IF (5, Insightful)

Ibag (101144) | more than 6 years ago | (#18553229)

"In the end, if Newton's Second Law could be violated, he would be forcing physicists to reevaluate much of what we understand derived from that law -- which is quite a bit.'"

In the end, if the second law of thermodynamics [or any other law of physics] could be violated, it would force physicists to reevaluate much of what we understand derived from that law - which is quite a bit. However, given that what we have derived from our laws generally fits with experimental observation (which is why we call them laws), the odds of him disproving Newton's second law with this experiment are about as good as me disproving the second law of thermodynamics by accidentally building a perpetual motion device.

Experiments disproving longstanding laws have happened before. People don't have reason to care about them until afterwards, though.

Re:A big IF (3, Insightful)

blank axolotl (917736) | more than 6 years ago | (#18553433)

The key is that our experimental observations only cover the cases we have thought to test - he would be testing the law in a new way.

In fact, we already know that newton's second law is wrong from special and general relativity, but you only see so at high velocities/high curvature of space. It was only once we had the theory that we knew how to test it properly. Here he is testing the law in the case of very small accelerations, based on a theory which tries to explain an astrophysics observation that is not well understood. Who knows, he might find something.

In addition, we already know that our theory from general relativity is incomplete because it does not match up to quantum mechanics, so there is surely still something to be discovered there somewhere.

Re: Relativistic 2nd Law (2, Informative)

Svartormr (692822) | more than 6 years ago | (#18553787)

...Newton's second law is wrong from special and general relativity...
Not if you state it in the form:

F = dp / dt
where F is the force on an object, p is the momentum of the object, and t is time; ie. the force is the time differential of the momentum. (And for completeness, p and F can be vectors.) Only with classical simplification do you get "F = ma".

Re: Relativistic 2nd Law (1)

zippthorne (748122) | more than 6 years ago | (#18554095)

The actually stated in the article,

Using momentum in the terminology (which would never have occurred to Newton) is a latter-day revision of the law to bring it into correspondence with special relativity.
But after reading that, I'm left wondering where the heck the rocket equation came from. and fluid dynamics. And whether a smart man is trying to blow smoke where smoke does not belong in the hopes of appearing even smarter for the purpose of getting grant money.

Re: Relativistic 2nd Law (5, Interesting)

blank axolotl (917736) | more than 6 years ago | (#18554129)

You're right that you can still use an equation that looks like F = dp/dt in GR, but I still think the original second law is wrong with all the quantities defined as they were. Writing it your way, it is then the definition of momentum which is wrong (or going on, the definition of velocity as dx/dt not dx/dTau). (Also in GR F= dp/dTau, not dp/dt if t is the time coordinate). The symbols in GR just happen to look and act quite like the newtonian symbols, but are interpreted differently.

Anyway, it is the error in predicted motion that is interesting here, where 'F=ma' gives the newtonian motion,
but this becomes like 'F = ma + m Gamma Vi Vj' in GR. You can't clearly see the different motions each theory gives in F = dp/dt.

Re:A big IF (4, Insightful)

Ibag (101144) | more than 6 years ago | (#18553889)

A few quick comments. First, relativity does not conflict with Newton's second law. It only needs to be changed from F=mA to F=dp/dt where p is momentum. Second, nobody said that general relativity was the pinnacle of physical theories. People have been trying for a while to find a grand unified theory that incorporated all the known forces in the universe and worked at both small and large scales. This appears to have nothing to do with the article, though. Third, while our experimental observations may only cover the cases we have thought to test, our laws are further verified every time the world behaves like we expect it to, every time we use GPS satellites with relativistic corrections, and every time we use devices that rely on quantum effects to work. The odds that everything holds except for 2/1000 of a second each year in two places on earth is unlikely. Maybe the experiment will work. That is science. However, it doesn't hurt to be skeptical until the experiment is done. I'm not saying that it won't happen, just that it seems premature to talk about rewriting textbooks just yet.

Re:A big IF (1)

blank axolotl (917736) | more than 6 years ago | (#18554205)

As I replied elsewhere, I think relativity does conflict with newton's law with all the variables defined as they were. If you redefine momentum to something new, sure, I agree. But newtonian mechanics *is* wrong after all.

As for the rest.. I actually know almost nothing about MOND, and I can't tell whether this experiment is worthwile. But my point was that universal laws have been shown wrong before, even when most observations seemed to support them.

Re:A big IF (0)

Anonymous Coward | more than 6 years ago | (#18554703)

A few quick comments. First, relativity does not conflict with Newton's second law. It only needs to be changed...
Wow.

Perpetual motion machine (0, Offtopic)

Khyber (864651) | more than 6 years ago | (#18553637)

idea for ya.

The universe blows up, expands, shit forms, eventually everything comes back, collapses, and another big bang happens. Repeat countless cycles, yet it keeps happening.

If you want to get into it, I'd argue that the universe, as open as it is, is a closed system without energy loss. But, this only works with the Big Bang theory.

As it stands, we'll NEVER know in our lifetimes. So, I just present something for you to think of - the perpetual motion machine could exist, but it's on such a scale that even galaxies of competent and intelligent life coudn't figure it out before the universe collapses upon itself from it's own gravity and wipes us all out.

Does this mean... (5, Funny)

AaxelB (1034884) | more than 6 years ago | (#18553231)

that Newton's Laws are actually just flawed theories? In that case, sign me up for the new "Intelligent Force" theory. Everything accelerates because something smarter than me decided it would, and there's no point asking questions. No more physics equations for me!

Re:Does this mean... (5, Funny)

amRadioHed (463061) | more than 6 years ago | (#18553307)

They prefer to call it "intelligent falling [theonion.com] ", but yeah you got the gist of it.

Re:Does this mean... (0)

Anonymous Coward | more than 6 years ago | (#18553569)

There *is* a point to asking questions, to satisfy your own curiosity and knowledge. Ask them all you want, no law (faith or otherwise) says you cannot, though sometimes it feels that way. BUT, when you take a theory and teach it consistently as fact when it's still a theory (and thus mislead others by your own flaws), that crosses the line. Hence all the controversy and debate and etc.

Like religion? (1)

FatSean (18753) | more than 6 years ago | (#18554909)

People teach their religion as fact. Sometimes even to young children who don't know any better.

Re:Does this mean... (2, Interesting)

TheManifold (844766) | more than 6 years ago | (#18553767)

Newton's laws are just very very good approximations of reality. Einstein's theories of general/special relativity are still even more accurate versions of reality.

An article in the New Scientist talks about 'Quantum Reality', where everything we see is just an approximation of the quantum world. I won't elaborate further, but I hope you get my gist.

Re:Does this mean... (0)

Anonymous Coward | more than 6 years ago | (#18553929)

May the Intelligent Force be with you.

Re:Does this mean... (0)

Anonymous Coward | more than 6 years ago | (#18555075)

Your post is indeed funny and I agree that intelligent design theories are worthy of mockery, however the part about contrasting the will to investigate the laws of physics with the existence of someone smarter than man is simply wrong. If someone smarter than you decided that things should be a certain way and he allows you to investigate them, I don't see a reason why you shouldn't be able to. By the way, I study physics because I like to, and that's the main point in asking the questions you refer to, in my point of view. Why is there no point in asking questions if someone more intelligent exists? I don't understand this, except if you refer to whether the existence of the more intelligent being might suggest that there are things that are more significant than knowledge in life.

Speed of Light Breaks it Already, Doesn't It? (4, Interesting)

BlackGriffen (521856) | more than 6 years ago | (#18553247)

I mean, NSL only applies in the case of slow moving/low acceleration objects because it assumes infinite propagation speed of the force carrier.

If he finds this it will be interesting not because of NSL concerns but because it would be an observation of the finite propagation speed of gravity. A fact that would serve as indirect (or perhaps direct) evidence of gravitational waves.

Re:Speed of Light Breaks it Already, Doesn't It? (1)

Plutonite (999141) | more than 6 years ago | (#18554411)

Speed of Light Breaks it Already, Doesn't It?
Yes, many of us have pointed this out, but apparently the man is proposing that relativistic form of the equation be revisited, which is a whole-nuther story. We're just nitpicking to be frank with you ;)

If he finds this it will be interesting not because of NSL concerns but because it would be an observation of the finite propagation speed of gravity.
I haven't done enough gravity to touch on advanced things like G waves, so I don't follow you. What I do know, as I posted somewhere below, is that cornerstone relationships like E=mc2 would very much go to hell, and quantum electrodynamics would have to be written from scratch. Relativity still holds as a mathematical/logical principle, but some fundamental axioms from which relativistic effects derive current relations will need to be modified, which is terrifying. I think he is wrong, but I wish him luck.

fagz (-1, Troll)

Anonymous Coward | more than 6 years ago | (#18553257)

fucking faggots.

Would it even be wrong? (1)

ameyer17 (935373) | more than 6 years ago | (#18553295)

Perhaps there's a force that hasn't been taken into account in his calculations...

Re:Would it even be wrong? (1)

SEWilco (27983) | more than 6 years ago | (#18553347)

Did he include the force of enough money for him to vacation at lovely polar locations?

Re:Would it even be wrong? (1)

devnulljapan (316200) | more than 6 years ago | (#18553441)

Perhaps there's a force that hasn't been taken into account in his calculations...
What kind of force? A bangy force? A pushy force? A growy force? A forcy force force? A magic man dunnit [scienceblogs.com] .

sounds like a free trip (2, Funny)

r00t (33219) | more than 6 years ago | (#18553367)

Think it'd be cool to visit Greenland?

1. be a prof
2. propose theory that must be tested in Greenland
3. profit

Re:sounds like a free trip (0)

Anonymous Coward | more than 6 years ago | (#18553489)

Oh, yeah... Vacation time in Greenland or the Antartic! I'm sure he's dying to visit either of those tropical paradises and vacation wonderlands and just cooking up the excuse of seeing if Newton's second law can be violated to allow him to catch some relaxation.

Now, if such were the case, and it was me that was proposing the experiment, I'd claim that the Carribean was the location where conditions were ideal- especially in the middle of a five-star resort hotel. I'd also up the duration necessary to measure the effect to a year.

Now, that's profit!

Re:sounds like a free trip (0)

Anonymous Coward | more than 6 years ago | (#18553545)

I think all the kewl people will stop at Iceland

Re:sounds like a free trip (0)

Anonymous Coward | more than 6 years ago | (#18554425)

Visiting Groenland should be *cool* in the real sense of word...

Why Not in Space? (2, Interesting)

vertigoCiel (1070374) | more than 6 years ago | (#18553373)

Am I missing something, or would this be a hell of a lot easier to do in space? From TFA I gather that he's looking for an instance of no outside force, and, since orbit is essentially free-fall, this would be easily accomplished on the ISS. Granted, I might be missing the point entirely, or I don't get his strange "I've got to do this on the surface of the Earth!" fetish.

IN SOVIET RUSSA (0)

Forrest Kyle (955623) | more than 6 years ago | (#18553375)

Mass Equals Force Times Acceleration!

Re:IN SOVIET RUSSA (0)

Anonymous Coward | more than 6 years ago | (#18553437)

Either that was a really lame attempt at an "In Soviet Russia" joke, or you're a bit confused...
F = m * a

Re:IN SOVIET RUSSA (1)

SageMusings (463344) | more than 6 years ago | (#18553747)

Lorentz factor, anyone? Why do people always forget that?

Very nice. May be important. (1)

Animats (122034) | more than 6 years ago | (#18553381)

That's a cute little paper. If other physicists think it makes sense, that little experiment is worth doing, even though some people will have to go up to the northern tip of Greenland to do it.

Re:Very nice. May be important. (0)

Anonymous Coward | more than 6 years ago | (#18553523)

That's cute little comment you have there. If other readers agree, it should be worth reading, otherwise it should be moderated down as offtopic.

HEY NEAL (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#18553395)

Neal unzips himself,
Three holes, two hands its not gay
unless the balls touch.

Dangerous? (2, Insightful)

Plutonite (999141) | more than 6 years ago | (#18553399)

Newton's law underwent some serious revisiting in 1905 when a chap called Einstein realised that masses are not constant/absolute but in fact relative, and this is why the modern relativistic notation differs quite a bit from the original F=ma. Now if this new guy is not joking (Russian timezones, April 1st, bit early..etc) then not only is our understanding of momentum going to be radically different, but in fact E=mc2 might have to be revisited as well (must read part 10 of this historical paper by Einstein [fourmilab.ch] to understand). That happens to be a very ground breaking idea if it were true, and would change lots of things we supposedly know about fundamental physics.

Re:Dangerous? (1)

julesh (229690) | more than 6 years ago | (#18554731)

Now if this new guy is not joking (Russian timezones, April 1st, bit early..etc)

The paper was published in December. That's a lot early.

Re:Dangerous? (1)

DiamondGeezer (872237) | more than 6 years ago | (#18554881)

Newton's law underwent some serious revisiting in 1905 when a chap called Einstein realised that masses are not constant/absolute but in fact relative, and this is why the modern relativistic notation differs quite a bit from the original F=ma.

Not so. Even in Einstein's relativity, mass is invariant [ucr.edu] .

Re:Dangerous? (1)

eyewhin (944625) | more than 6 years ago | (#18555047)

Newton's Second Law did not undergo any changes. It was, and always will be, F=dp/dt. The problem was the Newton had no way to test a change in momentum. There were no rocket engines, for instance. Having a running horse lose mass while shitting and then comparing the results before and after would have been difficult, to say the least.

David

Wonder how much testing this is worth (2, Interesting)

ThanatosMinor (1046978) | more than 6 years ago | (#18553551)

So for this thousandth of a second in a remote location at 80 degrees of latitude, is he proposing that we build an entire testing facility to see if an uncharged particle wiggles a little bit for some reason by some mechanism that no one has really figured out?
Are we also to believe that because the mathematical calculations work out such that all first- and second-order gravitational forces are cancelled, if we observe some motion, that motion is a clear violation of Newton's Second Law by assuming that there is zero force on the particle?
Wouldn't it be just as reasonable to claim that there were another force involved rather than saying that the Law has been debunked?

Re:Wonder how much testing this is worth (1)

toby34a (944439) | more than 6 years ago | (#18553721)

It seems that he's got ideas for mobile testing locations. Now, 80 degrees N/S doesn't seem like that great of a place to go, but it's somewhere where we don't have to put it on a rocket, which would require more funding. The materials (from TFA) that he proposes wouldn't be too terribly expensive to cart to Greenland/Antartica versus launching it onto the ISS.

Again, it's probably worth setting up some theoretical physicists up on top of a glacier just for the hilarity of it. But most of them are probably Russians, and used to the cold...

One thing about this... (1)

Nom du Keyboard (633989) | more than 6 years ago | (#18553553)

One thing about this is at least it can be tested for, and right here on Earth. But even if it's observed, that doesn't automatically prove his theory true. It would only add evidence to it.

Oh yeah? (4, Funny)

HardCase (14757) | more than 6 years ago | (#18553597)

You can take my gun from me...oh, wait, wrong 2nd law...

Laws aren't exactly "broken" in physics (4, Interesting)

thrawn_aj (1073100) | more than 6 years ago | (#18553601)

What laypersons should realize is that when a flaw is discovered in a well-established physical theory, it usually reduces the domain of validity of the theory, but RARELY makes that theory useless as a calculational tool (it just tells us when the theory will break down, as ALL current theories eventually do - the triumph of modern physics is to push those breakdown points to the farthest reaches of the imaginable). In this, physics has been an unqualified success - a fraction of the predictive power that we have today would have been enough to condemn several "soothsayers" to a grisly demise at one point in history :P. To digress for a moment here, it amuses me greatly that people can be obsessed with psychics and the contemptible Nostradamus while taking such exquisitely detailed predictions as tomorrow's weather for granted. It's rather like being impressed with a mythical flying superman while thinking of an airplane as mundane.

An example to illustrate the breakdown of theories: the Special theory of Relativity modified Newtonian mechanics on a fundamental level. However, for speeds much less than the speed of light (which is what most of us experience in daily life), it is STILL Newtonian mechanics that we use, even in several cutting edge research fields. The rule of thumb in research is: never use a full model when an approximate one is just as accurate in the domain of interest. In much the same way, even if MOND were true, any deviations from Newton would kick in at EXTREMELY LOW accelerations (of the order of 10^-20 m/s^2 which is about 10^-21 g, something next to impossible to duplicate in a lab because of ambient vibrational noise which is usually MUCH higher (say, about 10^-9 g is a VERY quiet environment)). This is the reason why the paper (which attracted our group's attention a few weeks ago) proposes an experiment at such well-defined times and locations. To put it bluntly, this is an ad-hoc modification in the sense that there is just no justification for the modification. Of course, I don't even think MOND would replace the Dark Matter hypothesis. One might even argue that this modification is simply a way of expressing the effect of Dark Matter (just a thought).

Not peer reviewed yet... (5, Insightful)

gb (8474) | more than 6 years ago | (#18553825)

It's worth pointing out that this paper is only publihed on a preprint server - that means it has not been through peer review, so needs to be treated with a lot of caution. There's an awful lot of totally crazy stuff on preprint servers. Not that I'm saying it's totally crazy - whilst I'm a physicist, I do condensed matter not astro - amd wouldn't describe myself as qualified to have a definitve opinion. But I would be both cautious and skeptical until proven oherwise.

Re:Not peer reviewed yet... (2, Informative)

Dr_Mic (975409) | more than 6 years ago | (#18554395)

Indeed, it is quite a stretch to say that putting a paper up on arXiv.org is "published" in any normal sense (say onethat would be accepted by a tenure review committee). However we do have

Is Violation of Newton's Second Law Possible? A. Yu. Ignatiev Phys. Rev. Lett. 98, 101101 (2007)

as well as

Mirror dark matter and large scale structure A. Yu. Ignatiev and R. R. Volkas Phys. Rev. D 68, 023518 (2003)


Geophysical constraints on mirror matter within the Earth A. Yu. Ignatiev and R. R. Volkas Phys. Rev. D 62, 023508 (2000)

and others.

The author has a real publication record. For phys rev and especially phys rev lett, the crank filters are a little more effective. As with the parent, this is not my field. However, my initial knee jerk reaction (crank!) has abated somewhat.

Re:Not peer reviewed yet... (1)

gb (8474) | more than 6 years ago | (#18554555)

For phys rev and especially phys rev lett, the crank filters are a little more effective.
Indeed, one would hope so. Especially if one is published in PR* :-)

These theoretical astrophysicists are getting good (3, Interesting)

Phroon (820247) | more than 6 years ago | (#18553827)

These theoretical astrophysicists are getting good at what they do.

The submitter of this article (and the populace of Slashdot as a whole) doesn't get the point of this article. Ignatiev isn't suggesting this experiment out of thin air, he's suggested a novel earth-based experiment to help explain the anomaly in galactic rotation (ie. Dark Matter). To explain this anomaly some theoretical astrophysicists modify Newtonian dynamics in a small way so that the galactic rotation calculations come out correct. Others introduce Dark Matter, or alter gravitation itself.

He basically wants to observe an object smaller than 7 cm x 40 cm x 40 cm at the precise moment and the precise location on the earth such that it would experience an acceleration that is much smaller than the extra acceleration it would experience as proposed by the modified Newtonian dynamics. So any extraneous acceleration observed at this moment had to have come from modified Newtonian dynamics.

The interesting thing about this article is that it isn't just a wild claim by a crackpot scientist, it's the proposition of an extremely accurate measurement using the most advanced technologies we have available. Of particular interest to me was that the proposed effect was two orders of magnitude larger than that observable by LIGO, a gravitational wave detector, suggesting that such an experiment is actually possible.

Take with a grain of salt (0)

Anonymous Coward | more than 6 years ago | (#18553919)

PhysOrg doesn't tend to have very high standards when it comes to the articles they post. Similarly, their forum is overrun with nutjobs and crackpots.

Though I haven't fully read the article, based on what I know of physics, this sounds like just another physics loony. I'd take this article with a grain of salt.

- Dave

mo3 0p (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#18554051)

Th3 futuRe holds

Wind your calendar (1)

Marko DeBeeste (761376) | more than 6 years ago | (#18554169)

Day early, dollar short.

Signal : Noise Ratio? (0)

Anonymous Coward | more than 6 years ago | (#18554437)

Erm,
Could this minute fluctuation in forces over a 1ms time-period be drowned out by any other fluctuation? Physical vibration? Magnetic flux? Gravitational flux? Noise in the measuring devices?

At least either way both sides will be able to deny that the result proved them wrong.

SHLEM (0)

Anonymous Coward | more than 6 years ago | (#18554439)

SHLEM [lingvo.ru] stands for `helmet' in the Russian language.

Both Sun and galaxies centers are accelerating (4, Insightful)

Alex Belits (437) | more than 6 years ago | (#18554473)

This article (and the whole MOND thing) would make some sense if the systems described in them were not accelerating because of gravity. Sun is subjected to the gravity forces toward the center of our galaxy, so its path relative to the center of the galaxy is not a straight line but a circle -- though a very large one. I find it to be an extremely weird oversight considering that the whole hypothesis exists to describe parameters of the very same motion of stars in galaxies. So even when a point on the Earth surface is not accelerating in the Sun's coordinate system, it still does in the galaxy's coordinate system.

Worse yet, MOND does not explain anything about galaxies because galaxies themselves accelerate. They are not distributed evenly and uniformly in space but form clusters. Each cluster just like a galaxy itself, is pulled together by gravity, so galaxies experience some acceleration in the cluster's coordinate system because of the gravity of other galaxies.

Obviously this acceleration is not detectable locally because it is caused by gravity -- for the same reason objects in orbit are "weightless". To find out that you are in freefall (or in orbit, what is the same thing) without looking at other celestial objects you have to throw something and observe its movement -- since gravity is not parallel and uniform everywhere, after the object will get far enough from you, it will be noticeable that its trajectory is not a straight line relative to you, as it would be if you weren't accelerating at all. However locally gravity and acceleration are indistinguishable, and at the scale of Solar system or galaxy the size of such "local" area is huge.

MOND is talking about absolute acceleration that should be clearly distinguishable from gravity. However if we will try to find something in the universe that is really "unaccelerated" by this definition, there will be very few objects in this category, if any. Certainly it would not be massive centers of galaxies, Sun or two spots on the Earth surface the author of the article proposes as locations for his experiments.

This is the theoretical part of the problem. Now, the practical one. In two proposed spots the conditions that article author expects to happen last for a very short time and happen once a year. The extent of effect is similar to the influence of gravity from many existing celestial bodies. Tidal waves caused by Moon and affected by the shape of oceans, condition in the atmosphere, movement of Earth crust, etc. are likely to produce more noticeable influence on any test body that may be used in the experiment. Though I didn't do any calculations, it's hard to believe that variations of tidal waves caused by changes in weather will be less than supposed effect of "modified" 2nd Newton's Law even if it worked the way that the article author's proposed. And since conditions are supposed to be so rare, there is no way to collect enough samples for any statistical analysis.

In the end, I can add that if your experiment is to look for a black cat in a dark room, it shouldn't be a surprise if the result is negative regardless of the actual presence of a cat. However this makes no excuse for proposing that the cat is in the room when there is no reason for it to be there in the first place. Both theory and proposed experiment look extremely stupid, and if MOND can be modified to explain why it should include movement of stars within galaxies but not movement of galaxies in clusters, maybe it would be worth a second look. For now it's just that -- stupid idea with no foundation and no viable method of verification.

Re:Both Sun and galaxies centers are accelerating (1)

julesh (229690) | more than 6 years ago | (#18554749)

So even when a point on the Earth surface is not accelerating in the Sun's coordinate system, it still does in the galaxy's coordinate system.

While movement on a galactic scale is quite rapid (in the galaxy's frame of reference), I believe the acceleration of any individual body is rather small, and can probably be ignored for any short timescale purpose.

Re:Both Sun and galaxies centers are accelerating (3, Interesting)

ThosLives (686517) | more than 6 years ago | (#18555217)

I don't think it has to do with acceleration of galactic centers. I think it has to do more with the effective radius used in the calculations.

For instance, in a traditional central-body problem, you have a very basic set of equations that says the path of any body around another body will be a conic section, with modifications due to more than two bodies in a system.

What I've never seen in literature, and I've seen the plot of angular velocity versus radius that "flattens out" for galaxies, is just what that angular velocity is? Is it angular velocities for individual stars, or an average?

If it is just an average, then I wonder is it an effect due to observation. What I mean is this: when looking at a gas here on earth, the average temperature is a good measure for its properties. However, only a small portion of the individual molecules in the gas actually have that exact temperature. The same for a stream of exhaust from a jet - the jet has a general average velocity, but each individual particle has some other velocity that contributes to the bulk average velocity.

I am wondering if the aggregate motion of a galaxy is like gas temperature or velocity; that is, it may be a superposition of the individual accelerations of the individual starts and nebulae in the galaxy. That is, is it possible to generate a system only with particles that obey classical (relativistic) gravity but can appear, in aggregate, to disobey the mass proportionality of Newton's Second Law? I suspect that 'galactic' measurements are like measuring bulk properties of a gas rather than looking at the kinetic model. Something perhaps like the recent storm on Saturn / water in a spinning bucket articles where simple motion of individual particles gives rise to more complex aggregate behavior.

testing a "zero" (1)

khallow (566160) | more than 6 years ago | (#18554505)

I think the point here isn't that there's some weird hiccup that only occurs during this brief time, but rather that standard theory predicts that a certain observation over this brief period should be zero while MOND predicts a nonzero value. Testing whether something is zero or not is one of the more sensitive types of tests out there. As an example, it's a lot easier to figure out whether there is a person or not in a room than to figure out whether there are 1,000 or 1,001 people in a room. By measuring during this brief time, certain normal effects, which would drown out the data that this guy is looking for, are absent. It eliminates a source of error in the experiment assuming his calculations are correct.

Fa(ilzors (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#18554579)

= 1400 NetBSD [gay-sex-access.com]? and piss cocktail. sling, return it to windo3s, SUN or BSD has always

he published a paper? (1)

drolli (522659) | more than 6 years ago | (#18554865)

now, please everybody repeat after me: A link to thre preprint archive is not a link to a published paper, because a preprint is a preprint and a paper is a paper (even if it is pdf nowadays....).

Let's get physical. (0)

Anonymous Coward | more than 6 years ago | (#18555027)

First of all, Newton's laws of motion are not Universal, we know it. More than one hundred years ago, Einstein proposed his "extended version": relativistic dynamics, which works fine in the case of high speeds, twenty years later Schrödinger and Heisemberg along with other geniouses formulated Quantum Mechanics(our most powerful theory). Years later, more theories have appeared, very beautiful and fine theories which describe physical phenomena correctly where you "can" apply them, I mean, a physical theory, as Newton's laws of motion, are just a mathematical model(cool differential equations, or more abstract stuff) and which describes nature whitin it's limits... every model has a domain of application and whenever you apply it out of it you can get weird things(the problem is that actually the limits of this domain are not well defined).

Newton's laws of motion and all which can be derived from them work extremely fine in our macroscopic dayly world... But whenever you look to something very little(one atom), you need to apply Quantum Mechanics, and whenever it moves fast(near the speed of light) you need relativity, or if both happens Relativistic Quantum Mechanics... and so on, you just say:"ok, here I will found a couple of non-classical effects, so I need a non-classical theory, let's forget about Newton and use another theory", but Newton's law of motion are still valid!, they've been used for describing the macroscopic world extremely well since they were formulated more than two hundred years ago, and today, we have no experimental evidence of a change in the way nature works and so we can be confident about the usefulness of Newton's law of motion... for every-day life(if you work in a particle accelerator forget about the last :) ).

This russian guy may have just devised a method for measuring some weird effects... :). But we can still go to Antartida and use Newton's law and they will be fine :).

I'm testing the SCHLEP theory... (1)

jpellino (202698) | more than 6 years ago | (#18555273)

Which postulates that the amount of time for a research assistant to get back from Quiznos is directly proportional to the gastric sounds of everyone else in the lab, and inversely proportional (to the second power) of the immediacy of the stuff left to do in the afternoon.

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