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Emergent Gravity Disproved

timothy posted about 3 years ago | from the what-does-this-guy-know? dept.

Math 102

kdawson writes "A paper up on the ArXiv claims to disprove the gravity-from-entropy theory of Erik Verlinde, which we discussed soon after he introduced the idea in a symposium late in 2009. Archil Kobakhidze says that experiments measuring the effect of gravity on quantum particles (neutrons in this case) match results expected from classical Newtonian gravity, not Verlindian entropic gravity. Here is Kobakhidze's paper (PDF)."

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102 comments

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Author James P. Hogan used this theory (2)

MadMike32 (1361741) | about 3 years ago | (#37228358)

In his Giant Star novels, if I recall correctly. The great breakthrough in physics by the aliens was the understanding that gravity was a consequence of particles decaying rather than through the standard Einstein model. Kind of puts a torpedo through that aspect of the books.

Re:Author James P. Hogan used this theory (1)

Anonymous Coward | about 3 years ago | (#37228404)

That was only a glossover explanation to explain their gravity control. Technobabble with a small root in contemporary science.

Still, great series using medium-hard science and a fun reveal chain. Mod up parent, Inherit the Earth!

Re:Author James P. Hogan used this theory (1)

amillard64 (873902) | about 3 years ago | (#37228482)

Actually his novel The Genesis Machine dealt with this idea in much more detail. In that story the effect was used to create an artificial black hole through which energy could be poured and focused anywhere within the range of the detector's capability. It was used as an ultimate weapon and the two scientists who were the only ones who really understood it used it to eliminate all offensive weapons on the planet and stop all war.

Here we go again (5, Informative)

Anonymous Coward | about 3 years ago | (#37228428)

Kdawson, could you please try to have the first clue about something that you submit? This is a non-peer-reviewed article, fresh on the arXiv. It's a followup to an earlier article which was widely criticized within the community as being full of holes, and the arguments in this article are very very weak. At best it's an argument against entropic gravity, but it is a LONG way from a proof that entropic gravity is wrong.

The way that neutron states are treated here is questionable - see http://arxiv.org/abs/1104.4650 [arxiv.org] for a summary of what's wrong with them.

Disclaimer: I am a gravitational theorist. I think gravity ISN'T entropic. However this paper is nowhere near sufficient to show that. I'd wait a LOT longer for the dust to settle on this one before making a strong statement one way or the other.

Re:Here we go again (5, Funny)

Zedrick (764028) | about 3 years ago | (#37228462)

> I am a gravitational theorist.

I don't even understand what that title means, but it sounds very cool.

Re:Here we go again (5, Funny)

patlabor (56309) | about 3 years ago | (#37228498)

> I am a gravitational theorist.

I don't even understand what that title means, but it sounds very cool.

He attracts a lot of ideas...

Re:Here we go again (0)

Anonymous Coward | about 3 years ago | (#37228630)

In theory at least.

Re:Here we go again (1)

modmans2ndcoming (929661) | more than 2 years ago | (#37231640)

woosh....

Re:Here we go again (0)

Anonymous Coward | about 3 years ago | (#37230806)

> I am a gravitational theorist.

I don't even understand what that title means, but it sounds very cool.

He attracts a lot of ideas...

Shit rolls downhill, eh?

Re:Here we go again (1)

shikaisi (1816846) | more than 2 years ago | (#37231682)

> I am a gravitational theorist. That's really heavy, man.

Re:Here we go again (0)

Anonymous Coward | about 3 years ago | (#37228512)

It means he is probably a theoretical physicist that focuses his work on gravity/gravitation.

Re:Here we go again (-1)

Anonymous Coward | about 3 years ago | (#37228714)

It means his name is Leonard.

Re:Here we go again (-1)

Anonymous Coward | about 3 years ago | (#37230100)

It means his name is Leonard.

Part 6!

Re:Here we go again (0)

Inzite (472846) | about 3 years ago | (#37228752)

> I am a gravitational theorist. I don't even understand what that title means, but it sounds very cool.

It means the GP is a self-proclaimed expert at cracking Yo Mama jokes.

Re:Here we go again (0)

Baloroth (2370816) | about 3 years ago | (#37229298)

I am a gravitational theorist.

I don't even understand what that title means, but it sounds very cool.

I think what you meant was "it sounds very attractive."

Re:Here we go again (0)

maxwell demon (590494) | about 3 years ago | (#37229496)

I am a gravitational theorist.

I don't even understand what that title means, but it sounds very cool.

I think what you meant was "it sounds very attractive."

Only in theory.

Re:Here we go again (1)

Walkingshark (711886) | more than 2 years ago | (#37232568)

> I am a gravitational theorist.

I don't even understand what that title means, but it sounds very cool.

It's a regular theorist who lives solely on a gamer diet (cheetos and mountain dew).

Re:Here we go again (1)

black soap (2201626) | more than 2 years ago | (#37232578)

> I am a gravitational theorist.
I don't even understand what that title means, but it sounds very cool.

I'm going to start telling people I'm a gravitational engineer.

Re:Here we go again (1)

Cant use a slash wtf (1973166) | more than 2 years ago | (#37232624)

I think it means most of his work revolves around him.

Re:Here we go again (0)

Anonymous Coward | more than 2 years ago | (#37239538)

I think it's a fat joke, but I'm note sure. I suggest we wait a LOT longer for the dust to settle on this one before making a strong statement one way or the other.

Re:Here we go again (1)

Anonymous Coward | about 3 years ago | (#37228480)

This is a non-peer-reviewed article ... and the arguments in this article are very very weak.

I wish they would hurry up and peer-review it so it would be correct.

Re:Here we go again (1)

V!NCENT (1105021) | about 3 years ago | (#37228792)

There's nothing to peer review, because the 'paper' doesn't publish a new theory. All it says is that resulting forces require a statistical 'average' of a couple of forces and that statistical analysis resulst doesn't match with what the entropic force theory calculations predict, but does match with Newton gravity.

That doesn't disprove entropic gravity, but merely sais that the current formula's not correct.

Re:Here we go again (1)

CSMoran (1577071) | more than 2 years ago | (#37234826)

This is a non-peer-reviewed article ... and the arguments in this article are very very weak.

I wish they would hurry up and peer-review it so it would be correct.

Note that "and" is not the same as "thus".

Paywall (2)

tepples (727027) | about 3 years ago | (#37228490)

This is a non-peer-reviewed article

I was under the impression that a peer-reviewed article was more likely to be paywalled and thus inaccessible to those Slashdot readers who had already graduated.

Re:Paywall (0)

Anonymous Coward | about 3 years ago | (#37228542)

After peer review, articles don't disappear from the arXiv. They're still there, still accessible to anyone who wants to view them - and most responsible authors update their submissions to reflect any major changes made during the review process.

Let me explain this to you... (1)

Anonymous Coward | about 3 years ago | (#37228502)

...in very simple words:

Exciting headlines get page hits.

A statement like "some data gathered might suggest gravity isn't entropic" will get very few page hits, and hence generate very little ad revenue.

A completely wrong but much more interesting statement like "Emergent Gravity Disproved" will get more hits, and hence more money.

So, Kdawson has every incentive to state the title wrongly, whether he understands it or not.

Complain all you want, the nature of the beast does not change.

Re:Let me explain this to you... (1)

Old Wolf (56093) | about 3 years ago | (#37230162)

I guess you didn't actually read the linked paper.. the paper itself explicitly does claim to disprove the Verlinde theory of emergent gravity

Re:Let me explain this to you... (1)

CSMoran (1577071) | more than 2 years ago | (#37234846)

Yes, and for emergent gravity to be disproved the (claim made in the) paper would have to be correct. The grandparent of your post (which, I guess you missed) gives convincing arguments towards the contrary.

Re:Here we go again (1)

tloh (451585) | about 3 years ago | (#37228514)

Kdawson, could you please try to have the first clue about something that you submit?

Those are fighting words, mate! It almost sounds like you're gunning for a newly vacated position [slashdot.org] . In which case you probably should have worked up the courage to post as someone identifiable rather than AC.

Re:Here we go again (0)

Anonymous Coward | about 3 years ago | (#37228600)

I post AC because I work in the field, and I don't want to piss off someone who could one day be deciding whether or not I get funding.

Re:Here we go again (2, Insightful)

tloh (451585) | about 3 years ago | (#37228846)

That is a poor excuse for choosing to express yourself as a rude condescending jerk. kdawson may not have the subject matter expertise to evaluate the strength/merit of what he felt was something cool and worth sharing - news for nerds. But how is it you choose to ignore timothy's role as a gate keeper for what is worthy of slashdot? Your own disclaimer express an opinion that the dust has yet to settle - even among experts. Yet you pull no punches in expressing your own opinion and expect us to take it at face value. That isn't the actions of someone fearful of future funding. It is the mark of someone too arrogant to acknowledge progress in science as necessitated by a series of meaningful arguments and counter-arguments within a framework of mutual understanding. What understanding did you attempt to foster here? I'm afraid you have a very skewed understanding of the slashdot community if you expect the link you posted to really mean anything for the majority of readers here. Take a good look at the replies to your post - half of them are cracking jokes and the other half are decidedly not impressed about the nature of scholarly publication. When your done feeling smug and self-important it would be helpful to consider how to undo the damage your post did by obfuscating the subject. An expert is useless if (s)he is incapable of communicating that expertise.

Re:Here we go again (1)

Forestwalker (2428752) | about 3 years ago | (#37229008)

At the risk of sounding like I have an IQ of 10.. I can not help but say I am amazed at the intelligence in here. I know that I have the Cells to learn like many of you.. study and think in such a way as to talk-write coherently , yet not the education you all have. I see the divide between the obviously brilliant and the not so. I see the analytical minds.. the truly scientific minds.. those who REALLY understand so many types of Science that they can connect dots in their head and state brilliant things. I know many of us who read here are not as well trained as those of you who are of that camp. But I can not help but come back over and over again.. and watch the snarky.. and the brilliance shown here. I think.. having this sort of mind.. must-needs have an attitude.. at sense of sarcasm .. though the smugness we could all do without. I think I learn from the IQ heavy and the Lack there of's equally. and I love to see some one Put things into Clear perspective.. clear Point of View.. watching an Analytical Mind.. state things in truly amazing Order.. I wish I had that discipline. I am told My IQ is only about 128. But I think that can be wrong..and I could learn over years of Training.. to think more like some of you do. But I just wanted to NOD and Tip hat to the Brilliance and Snarks of /. Keep it up.. ( goes to pop pop corn and sit back and watch the thinkers and well.. wish they could's ) I mean none of this as a strait out But kiss.. but.. I still think.. it is amazing to watch brilliant minds work. Now.. could we solve the Debt problem and Economy now ? New Guy.

Re:Here we go again (1)

tepples (727027) | about 3 years ago | (#37229122)

As I see it, snark comes from neocynicism [wikipedia.org] : having seen so much of the world and having one's reasoning been ignored so often that one needs to find some outlet for frustration.

Re:Here we go again (1)

Forestwalker (2428752) | about 3 years ago | (#37230476)

Thanks.. I guess I am not well versed.. though , It almost fits. I am surprised some one didn't flame me out for being too.. Uneducated to speak to the Post on Gravity. I think my wisest comment.. could be.. WE, just don't know. But it is good to try the theories. I can follow about half or less of what folks say.. That being I have not studied as you , many of you, have. I hope no one minds me sitting in.. and watching and learning.. I'll try not to be the DUH guy in the room. To be honest.. when I grasp a bit of what is said on these Posts.. I look really smart in Conversation.. pretty sad.. but.. true. At least , Tepples, you were kind.. thanks. Man.. are the whole lot of you MIT Grads? Super Coder writers ? Science Professors ? I read almost daily.. and for a few years now. Stimulating.. IF I had the education.. I see the way you all think.. how you form your ideas.. the order some put them in.. Fascinating.. It makes me think.. makes me theorise.. but I have none of the terminology to rightly state my ideas. i could try and state my idea's here.. but the Learning Curve would get me shot down.. I am sure. So.. me and Orville will sit back and read , watch the Sarcastic.. Ignorant and Brilliant.. pound out the real meat of it.

Re:Here we go again (1)

vbraga (228124) | about 3 years ago | (#37231010)

I'm sorry and I don't really want to sound rude in any way. You sound interested by science and higher learning, but also sounds like you didn't had the chance to tackle it. If my impression is correct, why not just go for it as an adult? If it's quite rare to see a motivated learner and it's sad to see talent not being used.

Re:Here we go again (1)

Forestwalker (2428752) | more than 2 years ago | (#37242826)

That was very kind.. not rude at all. I have been reading.. some times I think , by the time I have finished someone's Idea.. quantum has passed it by. I am searching for work right now.. Went through all of the Economic crap with a JOB till last year.. doing ok. Was scheduled to start at ITT in Long Beach last year. Had to put that down. I have been Playing with Linux for a few years.. and I do mean 'playing with'. I am still not a Command Terminal guy. ( except some simple simple basics. ) I read in science (s) I follow some trains of thought.. the ORDER some of you bring to thought is Stunning.. I could listen to folks like this talk all day long. i would think there are a dozen or so classes that bring this order. I think Going back to school.. would be like going to high school again.. Chemistry.. I don't even know the Tables.. Higher Math.. the Forms of Research.. Logical thinking.. I am not sure why.. but my Image of the Universe seems to gravitate.. sorry for the pun.. towards it being woven like a tapestry. I would not be surprised if Gravity were a reaction to set of Elements found in matter.. the larger the reaction.. IE a sun.. the higher.. putting off a field.. one that repels and when coming into contact with others of that Element.. attracts. Positive and negative in a sense. I get this idea that all suns are some how networked and affect each other. Not just by gravity but the reaction.. my idea.. causing the gravity. I would not be surprised if there were a full lack of some Element in a moon.. that would cause a sun to repel it from the sun. All half brained ideas.. none based off of any sort of Science.. I am sure.. just an Image in my head. I think the repel is what causes the ever expanding Universe.. and the Attract is what keeps the simple orders of things. But nothing like this could be added to /. I have no science for it.. all pipe dreams.. no research.. I can not even write my idea citing any other person who has half an idea like mine. But I would love.. In school.. to study why this idea can not be.. what Facts do we know that shoot it down. Then discover Where my gut feeling of a Network , Tapestry or such.. could come into play. Thanks for again being very Kind.

Re:Here we go again (1)

vbraga (228124) | more than 2 years ago | (#37244070)

While I know little of ITT Long Beach (I'm half planet away from California right now) you have, in the US, one of most interesting opportunities ever aimed at adult learners. This opportunity is called the Harvard Extension School [wikipedia.org] .

Don't let the Harvard name put you off :)

Harvard Extension School is a distance learning school of Harvard University. You can take both online classes and on campus classes (in Cambridge, MA). It has a very simple - and meritocratic - admission system:

You must take (and get at least B grades in) three pre admission courses. One of them is expository writing, which all prospective students must take. Two from a list of courses which varies from "concentration area" to "concentration area". One of the concentration areas is science, which is your interest. Before the expository writing course, you must take a placement test ("test of critical reading and writing skills", more about it here [harvard.edu] .

Rest assured the classes are going to be as interesting (and hard :)) as if you're admitted to any other undergraduate Harvard school. You will have a instructor (and fellow students) to help.

Harvard offers some options of financial aid for the pre admission courses (read more about it here [harvard.edu] - I'm assuming you're an American citizen, there is very limited support for international students). After admission there are way more financial aid options. Also, HES can be surprisingly cheap.

Willingness and motivation to learn are a rare characteristic in students and should be nourished. Do something about it :) I promise you it will be way more interesting than school ever was.

If I can help you in some way, just let me know.

Re:Here we go again (0)

Anonymous Coward | about 3 years ago | (#37229666)

First you claim my link will mean nothing, yet TFA links to the same website, citing papers. My opinions are within a comment, not the title of the whole article, and my opinion is that there remains to be work done, not that the whole thing is settled in a controversial and not well accepted five page paper which has been posted somewhere that has no filters.

If Kdawson doesn't know what he's talking about, as appears here, he shouldn't be titling articles with such strong statements. I would have accepted 'disputed' but 'disproved'? Utter rubbish.

The understanding I tried to give is that this paper is NOT well accepted, earlier work in the same vein by the same author have met with opposition from some other researchers in the area.

When you're done being insulting, perhaps you could realize that it hurts my field to have statements such as this plastered over the more popular press that we get (Yes, for us Slashdot is popular press). This kind of thing leads to people believing that EG is a dead end and removing its funding without a deeper understanding (Try navigating NSF funding avenues - you'll come across people who have read articles in newspapers about the science you're trying to research and will thus consider themselves experts).

I work in an area that competes with EG - I think EG is wrong. However, it has NOT been disproved so far as most experts in the field of gravitation would agree. I merely attempted to point out that it is a disputed area, and that uninformed people have no business making attention grabbing headlines about its death prematurely.

Re:Here we go again (1)

tloh (451585) | about 3 years ago | (#37230684)

Your willingness to engage in this conversation is appreciated. However, you still have not convinced me that kdawson ought to be criticized for not being a theoretical physicist. From the article his submission cited:

"Experiments on gravitational bound states of neutrons unambiguously disprove the entropic origin of gravitation," he [Kobakhidze] says.

You are well within your rights to express disagreement with such strong language, but why single out kdawson - who seems merely to be a messenger for someone else's words? You should just as well accuse MIT's Technology Review of ignorance and sensationalism since they are the originators of the article to begin with.

In any case, you've missed the point I was trying to make. Given the state of discussion on such a highly disputed subject area, you - as someone who probably has more to offer than most - has a chance to make positive contributions toward understanding it. You've failed to do that in numerous ways. Most importantly, (and this was my original beef) you claim authority on this subject while refusing to offer credentials and hide behind anonymity. Your defense (real or not) comes off as rather selfish really - why should *your* funding security have any bearing on why we should be persuaded by your opinions?

I'm sorry you feel insulted, but perhaps your concerns are misplaced to begin with? I don't agree that Slashdot is a popular press with much ability to influence the direction of NSF grants. We don't nearly approach the numbers of reader of TIME, Newsweek, WSJ, or any other mainstream news sources that command the attention of the voting public elected officials (and by proxy appointed officials) answer to. You should remind any slashdoting grant reviewer that this is also the website that played host to "OMG! Ponies!" and "Kathleen Fent Read This Story....." But if I'm wrong, you'll need to work much harder at elevating the professionalism and discriminating standards of this essentially ad-hoc community to the point where the content is reliable and reputable enough to make meaningful decisions.

Re:Here we go again (0)

Anonymous Coward | about 3 years ago | (#37230984)

I don't have to supply credentials - I merely linked to an article in which someone WITH credentials took this author's work apart. That, at the very least, makes his conclusions doubtful. My credentials really are irrelevant at that point, and I maintain anonymity as my colleagues really do read this.

I criticized Kdawson not for his lack of knowledge of theoretical physics, but rather for taking a single, un-reviewed, non-checked article on the arXiv. The arXiv,about anyone can post to, and so although great physicists post there, crackpots can do too and hence its not guarantee of the quality of the work. Then he takes this to state that the whole theory of EG is dead in the water. Not that some random guy is claiming it, or that it could be doubted, but the title says that it has been "disproved".

I tried to correct the misleading headline by pointing to another paper in which this is disputed strongly, and so remove the idea that EG is dead. That was my real aim here, and to stop it happening again.

As for NSF grants etc, a similar story got a colleague into a lot of trouble at a job interview - he was told that his field (Loop Gravity) had been disproved by experiment by one of his interviewers. On tracking down the source, it was a story on a blog not dissimilar to slashdot, which completely misinterpreted a paper, but by the time he'd done this, his chance of getting the position was zero, as the hiring committee had written him off. Whether we like it or not, we as physicists live in a world where our jobs are determined by non-experts who often like to pretend that they have some knowledge by reading pop-science stuff, and so calling out the pop-science writers when they do this is fair game.

Re:Here we go again (1)

tloh (451585) | more than 2 years ago | (#37231534)

Okay, one at a time.

I don't have to supply credentials - I merely linked to an article in which someone WITH credentials took this author's work apart. That, at the very least, makes his conclusions doubtful. My credentials really are irrelevant at that point, and I maintain anonymity as my colleagues really do read this.

Well, I guess we'll just have to take you at your word on that wont we? There is no way for us to know if instead of being a theoretician, you're actually just a really well-read waiter who's pissed at being beaten out by Jim Parsons during the casting of "The Big Bang Theory". Don't worry, we'll keep your identity secure from the other waiters. However, you really should forgive kdawson for not tipping you the other night. In all fairness you *did* spill his drink and ruined his pants.

I criticized Kdawson not for his lack of knowledge of theoretical physics, but rather for taking a single, un-reviewed, non-checked article on the arXiv. The arXiv,about anyone can post to, and so although great physicists post there, crackpots can do too and hence its not guarantee of the quality of the work. Then he takes this to state that the whole theory of EG is dead in the water. Not that some random guy is claiming it, or that it could be doubted, but the title says that it has been "disproved".

So instead of harassing us here on Slashdot, why don't you go complain to arXiv? I urge you to once again take another look around you. Most of us here are taking this WAY less seriously than you apparently are. Take a moment to think about how Slashdot operates. Stories are submitted, they are screened to filter out the spam, screened again for content relevance, then posted, then discussed. In that process, you are the only one thus far to be conspicuously screaming bloody murder at kdawson for committing a great unforgivable crime against the reputation of your professional field. The majority of us don't have the technical background to evaluate these types of ideas with a cursory glance. That is why we come here to talk about it - not listen to some AC randomly accuse others of being crackpots.

I tried to correct the misleading headline by pointing to another paper in which this is disputed strongly, and so remove the idea that EG is dead. That was my real aim here, and to stop it happening again.

Try harder. Your citation appears to be sourced from arXiv just like what you are railing against. Why should their refutation be taken more seriously? How do we know *They* are not the crackpots? If you really are as knowledgeable as you say, it would be easy to explain or summarize the meat of these publications to clarify the issue for those without the proper context. Instead you argue on the basis of reputation and credibility. You can do better.

As for NSF grants etc, a similar story got a colleague into a lot of trouble at a job interview - he was told that his field (Loop Gravity) had been disproved by experiment by one of his interviewers. On tracking down the source, it was a story on a blog not dissimilar to slashdot, which completely misinterpreted a paper, but by the time he'd done this, his chance of getting the position was zero, as the hiring committee had written him off. Whether we like it or not, we as physicists live in a world where our jobs are determined by non-experts who often like to pretend that they have some knowledge by reading pop-science stuff, and so calling out the pop-science writers when they do this is fair game.

If my previous comment was not understood, let me now make it clear: Slashdot is just fine the way it is. The problem with your grant reviewers' ignorance of what constitutes authoritative academic resources is beyond the scope of responsibility for "News for Nerds". Your frustration is hardly unique. Until last year, I worked for Genentech in the drug industry. You don't think I get headaches when encountering computer geeks trying to talk about biology-related topics on Slashdot? If like you I were to go up in arms over this, I'd probably start demanding every Slashdot poster memorize FDA rules, regulations, and guidelines for drug testing and manufacturing. Far more than just funding issues, lives are actually at stake in that arena.

Re:Here we go again (0)

Anonymous Coward | more than 2 years ago | (#37236240)

My point is this: You don't have to take me at my word at all. You just have to know that there is another paper out there that claims that this paper is in fact wrong. Therefore it's too early to state conclusively one way or the other on the death of EG, and so it shouldn't be the headline.

I'm completely fine with non-experts debating on /. - it's a wonderful thing! However, I think if in your work for Genentech someone had posted that their research was proven to be completely bogus based on a single paper that hadn't been reviewed at all, you'd take a similar position. I'm asking for _submitters_ of stories, or their editors, to not make such bold statements without some checking.

PS: I'm pretty sure that my waiting days are over, but I DID hate people who left no tips...

Re:Here we go again (1)

mikael (484) | more than 2 years ago | (#37232034)

You've got several choices depending on what you are contributing...

If it's something you remember from reading an article, reference the article. That's informative to other readers.

If it's something you have encountered in the past, that's experience and informative too.

As a researcher, you will be expected to maintain a research profile by publishing articles and papers. In your conclusions, you are going to have to express an opinion. It should be unbiased and based on empirical research.
Slashdot articles are a good way of practising.

Re:Here we go again (3, Interesting)

Freddybear (1805256) | about 3 years ago | (#37228566)

For more discussion of Kobakhidze's paper, and for criticism of the paper by Chaichian cited above, go here:
http://motls.blogspot.com/2011/08/once-more-gravity-is-not-entropic-force.html [blogspot.com]

Motl also responds directly to Verlinde here:
http://motls.blogspot.com/2010/01/erik-verlinde-why-gravity-cant-be.html [blogspot.com]
The discussion of a two-slit interference experiment in a gravitational field is clear enough that even I can almost understand it. ;)

Re:Here we go again (-1)

Anonymous Coward | about 3 years ago | (#37228638)

Kdawson is a shitball and a cunt. I hope he moves onto a hobby that he's more suited for. Like soap carving or knitting.

Re:Here we go again (1)

MightyMartian (840721) | about 3 years ago | (#37228898)

Or fathering another sibling for you...

Re:Here we go again (1)

buchner.johannes (1139593) | about 3 years ago | (#37228718)

This guy sounds pretty convinced and pretty much closes the chapter at the end of the blog entry http://motls.blogspot.com/2011/08/once-more-gravity-is-not-entropic-force.html [blogspot.com]

Re:Here we go again (1)

bar-agent (698856) | more than 2 years ago | (#37234678)

I admire the entropic gravity theory, from what little I can understand about it, though I am not sure I buy it.

That said, I am not sure I buy Lubos Motl Pilsen's rebuttal, either. He makes two two points that seem weak to me.

Instead of accepting the usual potential force as found by Newton, one must adopt an entropic force that depends on a temperature and an entropy. The temperature should be associated with the Unruh temperature which depends on the gravitational acceleration. This assumption is very problematic and probably inconsistent by itself because different pairs of bodies would have different temperatures which means that they couldn't be in a thermal equilibrium.

The bolded portion reminds me of a situation that requires calculus: when a naive constant multiplication gives the wrong result because the constant actually has to vary over distance or time. In this situation, the entropic potential force equation may have to have a temperature term more complicated than "tv" (me want Unicode) to account for a non-equilibrium. I do not see this as a deal-breaker.

But in agreement with his previous paper, he still assumes that the neutron may be associated with a wave function. If you try to do so, however, the momentum operator in quantum mechanics inevitably contains a non-Hermitian piece which takes care of the separation of the wave function among many microstates when the number of microstates goes up. Well, this is too optimistic because the relative phases between all the microstates would be undetermined and would evolve chaotically because of small differences in the energy between the macroscopically indistinguishable microstates - which would eliminate any trace of quantum coherence. But even if you assume that the quantum coherence is preserved, you get totally wrong new and very large terms in the SchrÃdinger equation that will obviously predict that the neutron interferometry experiments should see something completely different than what they do see.

As I understand it, these paragraphs are saying that as you drift into a sparser region of space and increase your entropy and degrees of freedom (i.e. increase the number of microstates), your wave functions gets noisy and you lose quantum coherence with a distant cohered particle as energy differences between different possibilities opened up by your increased degrees of freedom come into play. As Pilsen puts it, this is "because the relative phases between all the microstates would be undetermined and would evolve chaotically because of small differences in the energy between the macroscopically indistinguishable microstates."

Firstly, why would the microstates have undetermined relative phases? If two particles are coherent, and one exists in a one given space of microstates, and the other in another, then I do not see much of a stretch in saying that those different spaces of microstates are in some respects coherent as well, thus making their relative phases known as soon as one of the particles collapse. (Unless a "relative phase of a microstate" has some definition that is independent of quantum mechanics and cannot be influenced by the collapse of an entangled quantum state.)

Secondly, what does it matter of the microstates are macroscopically indistinguishable? For that part of the sentence to be relevant, I can only assume that Pilsen is talking about one microstate that "splits" into two or more if a particle moves to a place with more degrees of freedom. And so I ask, was it really one microstate to begin with, or was it two or more all along, with differences below some threshold that made them indistinguishable? Or, maybe a microstate can split as degrees of freedom increase, but maybe it does so in a stochastic way that maintains coherence.

Anyway, I am far from qualified to make convincing arguments. I will just wait for wiser heads to decide what's what.

Re:Here we go again (5, Informative)

bcrowell (177657) | about 3 years ago | (#37228922)

Kdawson, could you please try to have the first clue about something that you submit?

There's no reason to be so rude. In fact, I would consider the summary pretty accurate, although maybe not the title.

This is a non-peer-reviewed article, fresh on the arXiv.

Totally irrelevant. New research typically appears on arxiv first. That doesn't mean it's wrong.

It's a followup to an earlier article which was widely criticized within the community as being full of holes, and the arguments in this article are very very weak.

I'm not a specialist in this field (my specialty is experimental nuclear physics), but the impression I get as an outsider is that this is inaccurate. Actually many people in the field seem to find Kobakhidze's arguments very strong. I think the most fair summary would be that right now, the whole thing is controversial. Verlinde never claimed that he had a worked-out theory. It's always just been a rough heuristic. Even if it's right, it's wrong. What I mean by that is that it's at best a provisional picture (historically analogous to the Bohr atom) which needs to be reworked into a real theory (analogous to quantum mechanics). Just as there were no clear criteria for judging whether the Bohr model was a good idea or a dead end in 1915, there are no clear criteria for judging whether this idea is good or a dead end in 2011.

Re:Here we go again (2)

JamesP (688957) | about 3 years ago | (#37230268)

From the bottom of my heart, a huge thank you

This is the way science should go. Not "disproving theories" with barely acceptable arguments just because it's against the current theory.

Oh, btw (not for you), Einstein's General Relativity is not a theory OF gravity, it's a theory of how things behave in a gravitational field, it doesn't matter if it's a field, particles, entropy or bunnies causing gravity.

Re:Here we go again (1)

SoftwareArtist (1472499) | about 3 years ago | (#37230348)

I think gravity ISN'T entropic

Could you elaborate on that? What are your reasons for thinking that? It seems to me that emergent gravity is an obvious conclusion from the holographic principle. I'm not a gravitational theorist and I don't claim to fully understand these things. But as far as I understand it, the holographic principle basically says that a really complicated theory with explicit gravity is exactly equivalent to a much simpler theory without explicit gravity. Given that, it seems obvious to conclude that the simpler theory is more fundamental, and the complex parts of the other theory are just emergent properties.

Your disclaimer is *not* a disclaimer ... (0)

Anonymous Coward | about 3 years ago | (#37231326)

... it's a *disclosure*. There are things called dictionaries that you should perhaps consult sometime ...

Re:Here we go again (1)

MrLint (519792) | more than 2 years ago | (#37231980)

Its just a theory. I advocate intelligent shoving ;)

Re:Here we go again (1)

xyourfacekillerx (939258) | more than 2 years ago | (#37232016)

Disclaimer: I am a gravitational theorist. I think gravity ISN'T entropic. However this paper is nowhere near sufficient to show that. I'd wait a LOT longer for the dust to settle on this one before making a strong statement one way or the other.

You can determine that by reading it? I can't imagine what complexities are involved, but how long did you spend on the paper, and also are there gravitational, like... experimentalists? You know, guys who take these theories and do experiments?

Aren't you a little...late (0)

Anonymous Coward | about 3 years ago | (#37228438)

Seriously, I read about this three days ago. If you're going to post stuff from the Technology Review arXiv blog, the least you could do is stay current.

What would you have bumped (1)

tepples (727027) | about 3 years ago | (#37228538)

Seriously, I read about this three days ago.

Would you have bumped the departure of Steve Jobs in favor of this story? If not, which story would you have chosen to bump? Think of Slashdot on weekends as a weekly publication that has articles of lower urgency.

NERDS! (-1)

Anonymous Coward | about 3 years ago | (#37228486)

God did it!

FSM did it! (0)

Anonymous Coward | about 3 years ago | (#37228678)

Surely thou jest. Everyone knows it was the Flying Spaghetti Monster (FSM) that brought about the existence of the universe. Your god is nothing but an accidental creation that was a result of FSM allowing its snot to achieve self awareness during the binge drinking that following creation.

Re:NERDS! (-1)

Anonymous Coward | about 3 years ago | (#37229148)

Yes. We all know... this gravity thing.... it's just a theory! :)

Motl comments (4, Informative)

Sara Chan (138144) | about 3 years ago | (#37228522)

Lubo Motl [wikipedia.org] has some additional, supportive, thoughts on his blog:
Once more: gravity is not an entropic force [blogspot.com]

Re:Motl comments (0)

Anonymous Coward | about 3 years ago | (#37230108)

My eyes!!! What a heinous background, depite the matter concernced.

Re:Motl comments (0)

Anonymous Coward | more than 2 years ago | (#37232402)

Once more: gravity is not an entropic force

okay for bonus points, explain what that means.

Great ! (0)

giampy (592646) | about 3 years ago | (#37228608)

It's great that something can be disproved in physics these days, it means that physics it's still alive as a science. I hope it's true.

Re:Great ! (-1)

Anonymous Coward | about 3 years ago | (#37228646)

It's great that something can be disproved in physics these days, it means that physics it's still alive as a science. I hope it's true.

Physics is quackery! Using your standards, why hasn't physics proven that God doesn't exist? Because they can't that's why!

Now, if you'll excuse me, I have to go to my volunteer job helping Rick Perry become the next President!

Gravity again? (5, Funny)

The Creator (4611) | about 3 years ago | (#37228666)

I thought that we decided to go with intelligent falling?

Re:Gravity again? (-1)

Anonymous Coward | about 3 years ago | (#37228742)

No we went with being a total ass every time something even remotely maybe sorta kinda possibly religious shows up.

Re:Gravity again? (1)

maxwell demon (590494) | about 3 years ago | (#37228772)

Of course. You know, information is neg-entropy. So if entropic gravity is disproved, then obviously information gravity is proved. Now information comes from intelligence, therefore we have intelligent gravity, i.e. intelligent falling.

Re:Gravity again? (1)

non-registered (639880) | about 3 years ago | (#37230764)

This was funny. If I knew what a mod point was and had one, I would have used it here.

Obligatory XKCD (0)

Anonymous Coward | about 3 years ago | (#37228728)

common sense... (0)

Anonymous Coward | about 3 years ago | (#37228812)

I'm not a physicist nor do I know how to do the equations that they use. However, I've never understood the bent spacetime model as it makes little practical sense, though it may mathematically work at times.

I'm of the contention that gravity is not a force at all. I believe that the following makes more sense. I believe there is a combination of electromagnetic forces combined with atmospheric pressure that keeps us grounded. Fluid dynamics seems to be where that math might exist.

I'd be interested to hear what others, who do understand some of the math, would think of that proposal, keeping in mind that there seems to be a number of theories that have fallen short recently. One in particular is the speed of light constant being shown to not be limited by such a constant, another 'capped' belief that made little practical sense proven to be incomplete.

l8r,
cj

Re:common sense... (2)

MightyMartian (840721) | about 3 years ago | (#37228914)

Translation: I'm a fucking moron who doesn't understand things, but loves to insist my ignorance is in fact someone else's problem, so I have no problem spouting pure idiotic bullshit, and through a combination of low IQ and high hubris factor, throw my retarded thoughts out there as if they weren't the mumblings of a halfwit.

Re:common sense... (0)

Anonymous Coward | more than 2 years ago | (#37232912)

"We mock what we don't understand" - Dan Aackroyd in "Ghostbusters.

Instead of tearing down and verbally assaulting or even going out of your way to debunk, try asking questions if you're confused. And by the way, I have a 138 I.Q. So you try spending some time being open to finding solutions and thinking outside the box and then we'll talk. Rude!

l8r,
cj

Re:common sense... (1)

maxwell demon (590494) | about 3 years ago | (#37228940)

I'm not a physicist nor do I know how to do the equations that they use. However, I've never understood the bent spacetime model as it makes little practical sense, though it may mathematically work at times.

I don't know what you consider as "making practical sense", but a theory which mathematically works (and GR doesn't work "at times", it works everywhere where we can test it) is considered correct.

I'm of the contention that gravity is not a force at all. I believe that the following makes more sense. I believe there is a combination of electromagnetic forces combined with atmospheric pressure that keeps us grounded. Fluid dynamics seems to be where that math might exist.

If gravity would need atmospheric pressure, there would have been major problems for the moon landing teams, as there's no atmosphere there. Also, you would have a hard time to explain how the sun attracts the planets. The only fluid in the solar system is the solar wind, and that goes away from the sun.

I'd be interested to hear what others, who do understand some of the math, would think of that proposal, keeping in mind that there seems to be a number of theories that have fallen short recently. One in particular is the speed of light constant being shown to not be limited by such a constant, another 'capped' belief that made little practical sense proven to be incomplete.

I think your proposal is disproved by the planets orbiting the sun, by the moon orbiting the earth, as well as by the moon landings (both manned and unmanned) and several interplanetary missions.

Also nobody has shown the speed of light not be limited (if you think of the Nimtz experiments, that one is just a misinterpretation of the experimental results).

Re:common sense... (0)

Anonymous Coward | more than 2 years ago | (#37232990)

I apologise as I know this raises more questions than anything and it's easy to just shun than to attempt to see the perspective I'm trying to share, especially since I know I don't 'speak physics'. Electromagnetism is something like 10 to the 36th power stronger than what the force of gravity is supposed to be, right? Well, the first thought most would have would be "Okay smartass, we may have iron in our blood but what about objects that don't have magnetic material in them." Well, I said electromagnetism not simply magnetism. And electromagnetism includes the electromagnetic spectrum of light, which I've heard some speculate that in fact all of creation at it's smallest is 'frozen' light. In other words, the photonic particles and the like are illusory and thus is the reason the double slit experiment shows that photons act as particles and waves. So any matter will have an attraction based on electromagnetic forces. So the 1/3 less 'gravity' of the moon could be due to simply the lack of an atmosphere.

Resonance seems connected to orbits and suggests there is still the electromagnetic connection.

And as for the mathematics of the speed of light... Okay, C+1. There. I've mathematically proven you can go faster than the speed of light. I understand there is an amount of respect that people strive for within acedemic and professional communities that tend to discourage people from taking leaps but it's kind of like using an over-patched installation of Windows that crashes ever other hour, but never being willing to look at UNIX because Windows "works, mostly".

l8r,
cj

Re:common sense... (1)

Marble1972 (1518251) | about 3 years ago | (#37230798)

Hi cj,

I think think the idea's got legs.

You can see some of my thoughts on this via the comments by Marble on someone else's blog. [dumbscientist.com] . (You'll have to scroll down / ctrl-f for gravity).

I gave up arguing not because he convinced me otherwise - but lets just say he has a greater belief in the infallibilty of published science that I (or history I believe) can afford to give it.

Cheers, Marble.

Re:common sense... (1)

evilviper (135110) | about 3 years ago | (#37230868)

I've never understood the bent spacetime model as it makes little practical sense

"Gravitational lensing" is a known, 100% solid, FACT. Doesn't matter how much you dislike the idea, world+dog has seen it's effects in action, here on planet earth.

I believe there is a combination of electromagnetic forces combined with atmospheric pressure that keeps us grounded

Nice. What keeps the atmosphere (the source of that pressure) grounded, then? Why don't high-altitude (edge-of-space) pilots go floating off? Why don't non-magnetic objects in vacuum start floating? How about the planets themselves, in a nice orbit?

Incidentally, I have a pretty low concentration of magnetic material in my body, and atmospheric pressure is lower the higher you go, so, much like swimming under water, that should mean we FLOAT to the top, not get held-down by it.

The only sense your idea makes is if you redefine your "electromagnetic forces" to something identical to gravity.

Don't take it too hard, kid. We were all angsty teenagers who thought we were smarter than the rest of the world, and developed plenty of misconceptions due to a poor education system and whatnot, which take many years to completely shake off and replace with knowledge.

Re:common sense... (1)

spektrumcreations (1924884) | more than 2 years ago | (#37233048)

I can do without the condescension. And it seems that type of arrogance to state that gravity is 100% fact, is merely your own assertion based on what we are taught in schools as fact, though it is only a theory still. Albeit one that is sufficient mathematically for most of our money grubbing endeavors. You're knee-jerk reaction to assume I only meant magnetism is not my fault. However, based on just that alone, electromagnetism is how much stronger than the supposed force of gravity? So even a little bit of iron in the blood would be sufficient, though what I said what electromagnetism, not magnetism. l8r, cj

Re:common sense... (1)

orkysoft (93727) | more than 2 years ago | (#37236518)

The funny thing about science is that you can do experiments to see who's right. You don't have to endlessly debate stuff.

GP states many experimental observations that directly contradict your hypotheses. Now you can whine about condescension, or man up and rethink them.

Re:common sense... (1)

evilviper (135110) | more than 2 years ago | (#37236554)

I can do without the condescension.

You've made a complete and total fool out of yourself by spouting off baseless nonsense that flies in the face of observed facts. Condescension is the best you can possibly hope for.

And it seems that type of arrogance to state that gravity is 100% fact, is merely your own assertion based on what we are taught in schools as fact

GRAVITATIONAL LENSING. Doesn't have a damn thing to do with what school you went to. You can grab a telescope and go observe it, in action, RIGHT NOW. At least go look it up.

Also, talking about dogma from what is "taught in schools" just proves you're a school-aged kid. An overwhelming majority of people here have continued their education independently after leaving school, and long-since dumped any dogma that school has imposed. See the discussions on global warming, dark matter, etc., which haven't much made it into school books yet.

Try not to go to far over the edge with your pet theories and disdain of the world. If you also continue learning after you leave school, you'll find that, while your teachers may be idiots who can't intelligently defend or debate the information you've being told, out in the real world there are a large number of very smart people developing all these theories, considering all conceivable alternatives, trying to disprove them all, and more.

Very Valid Theory (1)

HydraMirage (2448176) | about 3 years ago | (#37228910)

Considering the bunk and completely unproved concepts that physics is using currently ie. Dark Matter, Dark Energy, String Theory, Supersymmetry and the Higgs Boson. Even IF there is a Higgs particle, the Higgs does NOT explain gravity. Emergent Gravity is a VERY compelling concept. It could also explains Mass, Inertia AND the 2nd law of thermodynamics.
Currently it is obvious that physics has been stuck in a rut for decades. The discovery of virtual particles has yet to be fully incorporated into other theoretical aspects of physics. It is my understanding, that these virtual particles are the 'Ether' that Einstein had mentioned before he resorted to the cosmological constant.
In my opinion, these chaotic particles have an effect,Entropy. Areas with less virtual particles, like the occlusion between two near objects, experience a negative pressure, which we call gravity. Gravity is emergent from Entropy. Entropy is emergent from Virtual Particles.
Of course, this is pure conjecture. But I would love to hear other peoples opinions...

Re:Very Valid Theory (2)

maxwell demon (590494) | about 3 years ago | (#37229064)

Considering the bunk and completely unproved concepts that physics is using currently ie. Dark Matter, Dark Energy, String Theory, Supersymmetry and the Higgs Boson.

You are mixing together very different things here. For one, I don't think anyone is using string theory. And I bet you are not qualified to call even one of the concepts you mention "bunk".

Even IF there is a Higgs particle, the Higgs does NOT explain gravity.

As far as I know, nobody ever claimed it would.

Re:Very Valid Theory (1)

HydraMirage (2448176) | about 3 years ago | (#37229362)

And I bet you are not qualified to call even one of the concepts you mention "bunk".

I don't need to be. It is widely know they all the concepts I mentioned are UNPROVEN THEORIES.

Re:Very Valid Theory (1)

maxwell demon (590494) | about 3 years ago | (#37229444)

And I bet you are not qualified to call even one of the concepts you mention "bunk".

I don't need to be. It is widely know they all the concepts I mentioned are UNPROVEN THEORIES.

So you think that every unproven theory is bunk? In that case I want to inform you that I don't have a proof of the theory that your IQ is above 70. So I guess that theory, being unproven, is bunk, and therefore I'm safe in assuming that your IQ doesn't exceed 70.

Re:Very Valid Theory (1)

HydraMirage (2448176) | about 3 years ago | (#37229658)

So you think that every unproven theory is bunk? In that case I want to inform you that I don't have a proof of the theory that your IQ is above 70. So I guess that theory, being unproven, is bunk, and therefore I'm safe in assuming that your IQ doesn't exceed 70.

I think it's obvious who the child is here.

Re:Very Valid Theory (0)

Anonymous Coward | about 3 years ago | (#37230896)

I think it's obvious who is clearly wrong here.

Re:Very Valid Theory (0)

Anonymous Coward | about 3 years ago | (#37229996)

It is widely know they all the concepts I mentioned are UNPROVEN THEORIES.

Science doesn't work like that. You cannot prove a hypothesis; you can only falsify it. Before you shit on modern physics, please learn the basics of the scientific method first.

Re:Very Valid Theory (1)

tloh (451585) | more than 2 years ago | (#37232592)

thank you! short, sweet, and to the point. I have mod points today. Pity I posted to this submission earlier today.

Re:Very Valid Theory (0)

Anonymous Coward | more than 2 years ago | (#37245100)

You might want to read the Wikipedia article on the Dunning-Kruger effect. It's about you.

Re:Very Valid Theory (1)

HydraMirage (2448176) | about 3 years ago | (#37230240)

Virtual Particles, Vacuum Energy and Gravity. http://en.wikipedia.org/wiki/Vacuum_energy [wikipedia.org] Quoted from the Wiki page:

Vacuum energy is an underlying background energy that exists in space even when the space is devoid of matter (free space). The concept of vacuum energy has been deduced from the concept of virtual particles, which is itself derived from the energy-time uncertainty principle. The effects of vacuum energy can be experimentally observed in various phenomena such as spontaneous emission, the Casimir effect, the van der Waals bonds and the Lamb shift, and are thought to influence the behavior of the Universe on cosmological scales.

The vacuum energy also has important consequences for physical cosmology. Special relativity predicts that energy is equivalent to mass, and therefore, if the vacuum energy is "really there", it should exert a gravitational force. Essentially, a non-zero vacuum energy is expected to contribute to the cosmological constant, which affects the expansion of the universe. In the special case of vacuum energy, general relativity stipulates that the gravitational field is proportional to -3p (where is the mass-energy density, and p is the pressure). Quantum theory of the vacuum further stipulates that the pressure of the zero-state vacuum energy is always negative and equal to . Thus, the total of -3p becomes -2: A negative value. This calculation implies a repulsive gravitational field, giving rise to expansion, if indeed the vacuum ground state has non-zero energy. However, the vacuum energy is mathematically infinite without renormalization, which is based on the assumption that we can only measure energy in a relative sense, which is not true if we can observe it indirectly via the cosmological constant.

Re:Very Valid Theory (1)

rtb61 (674572) | about 3 years ago | (#37230378)

Of course if you want to have real theoretical fun, consider a black hole (important in Entropic gravity theory) no longer as a collection of compressed molecules, but as an oversized atom, where gravity, compression and extreme energy levels has forced a fundamental change in the arrangement of the subatomic particles that make up a black hole. Similarly that neutron stars and pulsars are attempting to behave like a very large transitional state molecule.

It is worthwhile to keep in mind that interactions at the normal molecular level are substationally different to interactions sub-atomic level and the problem lies in trying to correlate that difference.

Re:Very Valid Theory (0)

Anonymous Coward | more than 2 years ago | (#37234204)

Dark Matter and Dark Energy explain observations. No other theory is sufficiently explanatory. Those are the only two criteria needed for a theory to be considered valid.

It would be nice if physics were simple enough for you to comprehend. You're not going to get very far discarding theories based on their aesthetic appeal.

You want to hear other people's opinions? Okay. You're an idiot. You are so colossally ignorant of this subject that you should refrain from theorizing.

The Michelson-Morley experiment laid the concept of luminiferous aether to rest over a century ago. Einstein's work on relativity could be said to be a direct result of this experiment. Reviving the concept of aether now is just as silly as a flat earth cosmology. It is less rational than most conspiracy theories.

Having first been theorized 80 years ago, virtual particles are as "incorporated" [wikipedia.org] as it gets. As for your concept of emergent gravity, well, go read about the Casimir effect. You may want a towel to deal with the egg on your face.

Re:Very Valid Theory (0)

Anonymous Coward | more than 2 years ago | (#37234378)

dark matter exists. this is no longer up for debate. see also the bullet cluster. if you want a model without dark matter, you must explain why gravity doesn't even point towards normal matter.

Bad headline... (1)

History's Coming To (1059484) | about 3 years ago | (#37228960)

To be fair, the article only addresses one formulation of emergent gravity from a single hypothesis. To say the whole idea of emergent gravity is wrong is a little disingenuous. My pet theory (hey, a boy needs a hobby) is that gravity is emergent from a universe where the physics, the actual computation, has to be done to make anything happen. Apple falls to the ground? The universe has to perform the calculations to make it happen. If there's a processor limit then it would manifest as the speed of light, and if the calculations involving regions of space with mass ("particles") take a little more calculating then that section of space will be retarded in a timelike direction, ie GR. There's a whole host of emergent gravity or emergent relativity possibilities, and to my mind at least it's a very elegant way to get around some of the big fundamental problems, like why gravity doesn't seem to behave like the other forces, or why the speed of light even exists.

Re:Bad headline... (1)

nu1x (992092) | about 3 years ago | (#37230688)

Interesting.

Thanks for the insight; I also found interesting the point that centrifugal force and inertia are so gravity-like. So my intuition would say that gravity is heavily dependent on motion, maybe not only of macro objects, but also of micro objects (particles and their interactions, which may be why bigger particle conglomerations are more gravitic).

I am still working on this one tho, but I really think that gravity is motion (and by connection, time, which is the emergent property of motion) dependent. As in, in every moment of measurement, macro and micro scale structures (of the universe) change, in the process changing the force (maybe better told, the structure of the force) of gravity itself, which (in this case) may be dependent on motion based interaction in a given moment between the structurally diverse sea of particles, therefore giving this force such unusual (and sometimes unpredictable) characteristics.

Hope you could make sense of twhat I am speaking :D

Thanks for reading.

Re:Bad headline... (0)

Anonymous Coward | more than 2 years ago | (#37233976)

And together you two are a perfect example of what happens when people with access to popular science material think that they're actually physicists.

Just because you know the word "emergent" doesn't mean you understand what it means.

Re:Bad headline... (1)

History's Coming To (1059484) | more than 2 years ago | (#37240662)

In this context, that gravity isn't a fundamental force, but emerges from further underlying phenomenology. We've got a model of spacetime geometry, but no real explanation of why it's like that. Pretty much every scientific theory has been found to be an effect generated by a more fundamental underlying concept. Truly chaotic systems, for example, are ultimately generated by uncertainty at quantum scales.

If you could point out exactly why you disagree with me then I'd be glad to argue further.

Re:Bad headline... (0)

Anonymous Coward | more than 2 years ago | (#37232586)

speed of light exists so that the whole universe doesn't go to it's conclusion instantly.

Emergency Gravity (1)

DragonHawk (21256) | about 3 years ago | (#37229558)

At first pass I read the headline as "Emergency Gravity Disallowed".

My thought was, "Wow, this Hurricane Irene hysteria has really gotten out of hand. People are even afraid the gravity's going to get knocked out."

Obligatory (1)

TeknoHog (164938) | about 3 years ago | (#37230026)

-You're flying!

-How?

-Gentoo! [xkcd.com]

# emerge antigravity

another gravity concept (0)

Anonymous Coward | more than 2 years ago | (#37232406)

www.thomaswlynch.com/blog at the bottom. Postulates gravity follows from an expanding Klein bottle like geometry for the universe. Note the nifty animation graphic ;-)

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