gravitational hope

[Luke]

so i wanted to know what gravity was. nothing really came up that i could get suckered into believing, so i deceided to try make my own little theory.

im busy studying newton's laws in physics and the one thing that seems clear is that the fundamental law of the universe is that no object will move or stop moving without a force being applied to it. For instance centrifugal force doesnt really seem like much of a force to me, its just a result of an object wanting to move in a straightline, we've just called it a force because its results look like a force. so from this i thought that, okay every "force" is just a result of the fundamental law.

So now i wanted to use only this principle to discover a reason for the illusion of gravity, so i am going to propose that every atom( well actually everything, electrons, strings, quacs, not sure how you spell that one) in the universe was expanding exponetially.

My wording has been terrible, im sorry, so let me give an exapmple of what im trying to say.
Imagine the earth. Every atom of the earth is expanding, and because the earth is made up of so many atoms the earth is expanding faster than objects with fewer atoms ( this is why objects with a greater mass would have a greater gravitational pull). So you imagine the earth expanding exponentially( exponentially because if it was a constant speed then the objects would not be "pushed" onto the earths surface.

there are probably many flaws in this theory. one that seems immediately apparent is, " like hello dude! then howcome the earth hasnt become noticable huger with this exponential "growth" ". My answer is that everyting around is also expanding hence the tools made for measuring the earth are also getting bigger as well as our eyes and what not. Everything else expanding on earth also adds to its gravtional pull because according to this silly theory they too are expanding and "getting" closer to earth.

God i hate to post something that is so poorly worded, but anyway purlease read this and accept that it is nonsense but tell me why( we all accept the silly fact that time is relative so give this a try. i want to argue.

[freeztar]

If this were true, we'd measure a decreasing distance between the Earth and the Moon over time. In fact, the Moon is receding from us (a few cm per year, IIRC).

To make this theory line up better with observation, you would need to have space expanding in proportion with the masses. Since space contains very little matter, some other mechanism must be explained to cause space to expand.

Otherwise, every body in the solar system would expand into the empty space around it and eventually everything would merge.

I recommend checking out the wikis on gravitation and gravitons for some plausible explanations of the mechanism of gravity.

oh yeah...Welcome to Hypography!

[modest]

Luke, what you're saying doesn't sound too terribly different from the equivalence principle which Einstein used to derive a theory of gravity—general relativity (you may well know this, I don't mean to patronize). A person standing on the surface of a planet may 'seem' at rest, but it is they whose path is being diverted from Newton's inertial course—they feel acceleration. Likewise, a person who is free-falling toward a planet (with no atmosphere) may seem to be accelerating toward the planet's surface, but they feel no intertial force. They are weightless. They are following Newton's inertial path—the path of least resistance.

Einstein's solution was to model space and time as curved by mass. Your idea that massive bodies are expanding is interesting... it could be an interesting interpretation of General Relativity, but seems a little problematic. As Freeztar says, the moon maintains a constant distance from the earth. If the surface of the earth is really expanding away from its center then so too must the moon. Why then would the moon (or anything in orbit) not feel a pseudo force (if they are accelerating away from earth's center)?

~modest

[lemit]

I love your second sentence! If we were forced into honesty, all of us would admit to having used that technique more than once.

I'm going to assume your education level is not that of an MIT professor of Astrophysics who came to us after questioning his colleagues. I'm not a science-person, but I've heard the bases of your theory described with great fealty by science-persons. The only thing they left out was your conclusion, which, if I understand it correctly, is that gravity is kind of vestigial inertia. Is that it? That's the best explanation of gravity I've seen so far. Maybe a few words about homeostasis would have made it more palatable for the science-persons.

I know those science-persons have itchy fingertips from reading this, but I'm really impressed by what you've done. Congratulations and welcome to Hypography!

--lemit

[Jay-qu]

You started off well luke. This is exactly what Einstein questioned - what causes this mysterious 'force' to occur. So he got rid of it. In general relativity there is no action of one body on another, everything just follows straight lines. There is only one hitch, every mass distorts these 'straight' lines, so what we see is the apparent attraction of two bodies. Its a very nifty theory - brilliant mathematically and also satisfying conceptually.

If you want to have a go proposing your own theory of gravity you better aim for quantum gravity, then its harder to say your wrong..

[UncleAl]

Centripetal force is imaginary. If stuff expands and centers of mass remain as observed, you have a huge contradiction re lunar laser ranging and the Nordtvedt effect, sensitive to less than part per trillion relative over some three decades. Much of reality is nonlinear in distance. A zoom lens is not a consistent transformation any more than a mirror reflection is (re the Weak interaction, Yang and Lee).

If anybody meaningfully understood gravitation we could calculate Newton's G. We cannot. Unlike all other primary standards, the kilogram is an arbitrary physical artifact. The Standard Model arrives massless with everything flitting about at lightspeed, but reality is massed. Bridging that gap requires a 26 parameter jury-rig, constants

We can only describe gravitation and compare predictions to observations. Only one minimal description is unfalsified to date: General Relativity (1916; Einstein). Only one minimal description allows GR to be incomplete yet not contradict prior observations: teleparallel gravitation (1931; Einstein, Cartan, Weitzenböck). Only one GR violation remains unexamined: Do left and right shoes violate the Equivalence Principle? Physics cannot handle chemistry.

Manolo Blahnik shoes won't do it. The test masses would be macroscopically and chemically identical, opposite geometric parity atomic mass distributions. Single crystals of left- versus right-handed alpha-quartz would do it. Somebody should look, PURSUING THE LIMITS OF FAILED SYMMETRY

http://www.npl.washington.edu/eotwas...wfrontier2.pdf
http://wugrav.wustl.edu/people/CMW/update98.pdf>
http://www.astro.northwestern.edu/As...s/lorimer1.pdf
http://www.vallis.org/publications/tesidott.pdf
Equivalence Principle testing

Lunar Laser Ranging experiment - Wikipedia, the free encyclopedia
Nordtvedt effect - Wikipedia, the free encyclopedia

[Pyrotex]

Originally Posted by Luke

...So now i wanted to use only this principle to discover a reason for the illusion of gravity, so i am going to propose that every atom( well actually everything, electrons, strings, quacs, not sure how you spell that one) in the universe was expanding exponetially.....

I'm 63 years old. I heard that proposition back after I got out of graduate school. Call it 35 years ago. It went over like a lead balloon. Every decade or so, I see someone suggesting it. And it keeps going over like a lead balloon.

Sorry to pop your lead balloon, but that dog doesn't hunt very well.

[Ben]

Originally Posted by Pyrotex

I'm 63 years old.

You're kidding, right? Not only is NOBODY that old, you come across as being rather youthful. Good "old" you, keep seeming young!

-b-

[Pyrotex]

Originally Posted by Ben

You're kidding, right? Not only is NOBODY that old, you come across as being rather youthful. Good "old" you, keep seeming young!

Thank you muchly.

I maintain the appearance of youth by making up my own words, playing havoc with syntax, the frequent and creative use of smilies, the flumoxing utilization of grandiloquence and fancy phraseology, the oceanic inundation of my opponents with tsunamies of metaphor, analogy and discretely subtle sarcasm, and finally, a certain modest (but well-deserved) degree of intellectual self-aggrandizement.

And I still flirt with Buffy. When she gives me permission.

[CraigD]

Welcome to hypography, Luke! I hope you have as much fun here as I have.

Going straight to your idea about gravity being a purely mechanical effect due to the acceleration of the surfaces of bodies, I think as previous posters have said, this is an idea that, while attractive for a moment, has so many problems it has to be quickly discarded. It’s the central subject of a published and highly promoted book, which we discussed at staggering length in Anyone read The Final Theory book?, and apart from a few die-hard supporters of the idea and its various promoters, pretty much concluded it was a lot of pseudoscientific rubbish.

Picking one of a large list of problems with the idea, I’d chose the following:

The theory predicts that the surface of a body with noticeable gravitational attraction must be accelerating directly from its center of mass at the observed surface acceleration of gravity (9.8 m/s/s) as measured by something on its surface. The surface of a smaller body, say a 100 kg person curled roughly 0.5 m radius ball, should also be accelerating, but at a much smaller rate, as the gravitational attraction of such a small mass is much less, about (100*6.67428e-11/(.5**2) = .000000027 m/s/s).

Now, lets make a prediction based on this:
I measure the distance from my front door to the sidewalk, using my bare foot as a measuring device. For the sake of simplicity, let’s say I do it so quickly I can ignore any expansion of me and the Earth as I do it. I get a result of 50 foot-lengths.

Now I wait 20 minutes, and repeat. Theory predicts all linear dimension of the earth will have increased by a factor of at least (6378137 + (9.8/2)*(1200^2))/6378137 =~ 2.1, while all of my body dimensions – including the foot I used in the experiment – will have increased by a factor of at lease ((1 + (.000000027/2)*(1200^2))/1 =~ 1.02. So, repeating my measuring experiment, I should find that the distance to the sidewalk is now about 103 foot-lengths.

The experiment fails to match the prediction, so the theory fails.

Various people have tried to figure out a way to modify the “expanding everything” theory to solve this and many other experimental failures, none to my knowledge with any success. It’s hard to imagine how even this simple failure could be fixed with a modification of the original theory. Thus, most people leave the whole theory for dead.