What causes Gravity??

[MeteorWayne]

"- drak matter "<br /><br />That drak matter makes me want to hurl <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[billslugg]

majornature<br /><br />I can provide thought experiments that might provide mundane explanations of attraction and repulsion. It could be gravity, charge, magnetism, whatever.<br /><br />Repulsion<br />Two particles exchange a third particle. As if you and I were on the ice, playing catch with a heavy weight.<br /><br />Attraction<br />Picture a space filled with an unimaginably large amount of impossibly tiny particles traveling at high speed. The particles interact only with the tiniest of point sources in the heart of subatomic particles. If you and I stand facing each other, I shield you from some of the particles and you shield me from some of them. We are pushed toward each other. It appears as if we are being attracted. <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[fffranklin]

hmmm.. "pressure"? I don't see how you can come up with a new theory of gravity without any equations. It would be nice if this was possible, but I think you'd first have to at least be able to solve equations in general relativity, quantum field theory, etc. Can you do tensor calculus? I can't. <br /><br />new physics with no equations = not even wrong <br /><br />where's the math?

 

[vandivx]

I don't think equations are at all necessary, its ideas that matter and they can be put on mathematical basis later after you got ideas, if you don't have idea you are stuck no matter how brilliant mathematician you are and there's plenty of math brilliant postdocs out there and it does us fat lot of good methinks<br /><br />@billslugg, you can't be serius that idea is very old and disproved, if I am not mistaken it was around since Newton's times<br /><br />vanDivX <div class="Discussion_UserSignature"> </div>

 

[alokmohan]

Dangerously crankish.

 

[billslugg]

fffranklin, vanDivX,<br /><br />You seem to have missed the word "mundane". <br /><br />majornature appeared to be soliciting ideas as to how in the world two objects could be attracted/repelled to/from each other in the absence of any thing connecting them. I gave her "mundane" examples. Good enough for a bunch of folks sipping corn squeezings and kicking stuff around the campfire.<br /><br />Not intended to supplant current gravitational theory. You took me too seriously!<br /><br />No, I cannot do tensor calculus. I could in my younger days, before the pharmokinetically induced brain cell destruction set in. I highly recommend NASA's Joe Kolecki and his white paper on tensors. You can dip your toe in far enough to get a layman's understanding of what a tensor is, or you can wade in far enough to drown or you can swim all the way and become fluent. <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[science_man]

Can we agree that gravity is caused by intense heat? Just like Energy is proportional to Mass, Heat is proportional to the Gravitational pull. <br /><br />Example 1: The sun is extremely hot, it has extreme gravity.<br />Example 2: In outer space, it is very cold. there is almost no gravity.<br />Example 3: Black holes suck everything in... particles collide infinitely creating friction creating heat. Thus more heat, more gravity. <br />Example 4: When you split an atom you break the gravitation pull thus creating heat. And vise versa<br /><br />Theory 1: If there was a solid metal ball the mass of the sun in a diferent galaxy, the gravitation pull of the ball would be less than the gravitation pull of the sun. The reason: the sun has more heat than a solid metal ball. <br />Theory 2: Antigravity (dark matter) is below absolute zero. <br /><br />Why not? <br />It works right? I'm just trying to prove it using formulas instead of just giving examples. Heat is proportional to gravity! or so it seems...<br /><br />-- Nishant Shukla<br />

 

[vandivx]

not sure what your aim is when you talk about tensor calculus, IMO the equations of GR don't tell you how bodies can be attracted or repulsed, that is they don't give physical picture unless you consider space curvature physical phenomenon which is not the offical general interpretation I believe and it doesn't work in real 3d space anyway (I mean one can't understand curvature in 3d in any consistent, that is contiguous way)<br /><br />scientists if pressed about the physical picture of how repulsion attraction works will tell you in the end that all that matters is that we can calculate things and never mind the physical picture, same if you asked how QM works<br /><br />but you wanted to give simple folk explanation, why not that one with rubber sheet analogy of curved space where anybody can understand attraction/repulsion as far as that goes of course but normal folks by definition are such that they don't think too much and therefore think of asking how would it work in real 3d space because then they would be smart and not normal LOL<br /><br />interesting how that rubber sheet space curvature analogy seems not to be enough for people here as explanation of how gravitation works<br /><br />vanDivX <div class="Discussion_UserSignature"> </div>

 

[billslugg]

The only reason I mentioned tensors was that somebody asked me if I could do them. Yeah, the rubber sheet is a good analogy. But wait ... there is no rubber in space! Explain that one. Hah - gotcha! <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[MeteorWayne]

"Can we agree that gravity is caused by intense heat?"<br /><br />No, not at all. It has nothing to do with heat. <br />That's just a silly (as in Monty Python silly) idea.<br /><br />If that's the best you've got, you're not going to have much fun here.<br /><br />Welcome to Space.com!<br /><br />Wayne <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[majornature]

Speaking on that, I never thought for a second heat would cause gravity. I thought it was the other way around. But when talking about gravity and the universe, a lot of things get ruled out.<br /><br />So, I see gravity is very important...so why is it assumed to be the "weaker force"? <div class="Discussion_UserSignature"> <font size="2" color="#14ea50"><strong><font size="1">We are born.  We live.  We experiment.  We rot.  We die.  and the whole process starts all over again!  Imagine That!</font><br /><br /><br /><img id="6e5c6b4c-0657-47dd-9476-1fbb47938264" style="width:176px;height:247px" src="http://sitelife.space.com/ver1.0/Content/images/store/14/4/6e5c6b4c-0657-47dd-9476-1fbb47938264.Large.jpg" alt="blog post photo" width="276" height="440" /><br /></strong></font> </div>

 

[gammarayburst]

Yeah, why is gravity considered to be a weak force when it seems so strong at such great distances? It only becomes a weak force when dealing with small objects yet you can't pick up an automobile with one hand like you could with a tennis ball. So is it possible that because electrons, matter, the whole universe is expanding, are in motion they become energetic and thus attract like dust to a static charged balloon? I believe.<br /><br />Explain the lifter and why it defies gravity if gravity has nothing to do with the attraction/repulsion of electrons? Lol, ion wind! <br /><br />Another thing, we now know the moon came from the earth from a collision. So if we were able, hypothetically, to throw an object off the earth of that size wouldn't it bounce back because of the earths gravity? So if the moon wasn't captured then why didn't it bounce back? The moon effects the earth with its gravity but yet refuses to come back? Captured, wasn't that the explanation why the moon has not crashed into the earth? But it wasn’t captured! So by that there must be a "pushing effect" of matter when objects collectively are large enough to effect one another otherwise the moon would not be there today. <br /><br />I know someone is going to say I'm dead wrong and I really don't care, just seeking answers like everyone else besides no one else has yet to come up with a logical explanation with an ounce of similarities to the real world!

 

[Mee_n_Mac]

<font color="yellow"> So if we were able, hypothetically, to throw an object off the earth of that size wouldn't it bounce back because of the earths gravity? </font><br /><br />No, not if we were to "throw" it fast enough and in the right direction. We do this all the time with satellites. They go into orbit. And they're a lot smaller than the Moon. How do you suppose they stay up there ?<br /><br /> <div class="Discussion_UserSignature"> <p>-----------------------------------------------------</p><p><font color="#ff0000">Ask not what your Forum Software can do do on you,</font></p><p><font color="#ff0000">Ask it to, please for the love of all that's Holy, <strong>STOP</strong> !</font></p> </div>

 

[derekmcd]

I don't believe gravity is considered a weak force. It just happens to be weaker than the other 3.<br /><br />A refrigerator magnet is a classic example of electromagnetism being stronger than gravity. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[MeteorWayne]

At short distnaces, gravity is the weakest force.<br /><br />At large distances, it is the strongest. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[kmarinas86]

<b>Conservation of angular momentum is the basis for gravity</b><br /><br />Imagine a system of particles moving a certain way. In order to conserve momentum, they have to be moving in specific way. The fact we have gravity now is because of initial trajectories and their angular momentum. The conservation of angular momentum is more fundamental than the conservation of momentum, since no object travels a perfectly straight path.<br /><br />When we jump off the planet, we transfer a force, or a torque rather, on the planet. That can only take us so high until we fall back down, since angular momentum is conserved. When you jump, you produce vibration underneath your feet. When those vibrations slow down, so do their velocities, and they return back to normal, therefore you location to would have to return back to normal if you don't sustain propulsion: what goes up must come down.<br /><br />Objects with more mass spinning at the same velocity and at the same radius will have greater moment of inertia. It will therefore have more gravity simply because the conservation of angular momentum requires it. It's like the heavy male skater versus the light female skater.<br /><br /><b>Gravity is just an extension of the conservation of angular momentum.</b>

 

[kmarinas86]

<b>Gravity on earth</b><br /><br />As you are just about to jump, you are increasing the force between you in the ground, and they by decreasing the distance between the atoms of your feet and the atoms of the ground. Such distance become smaller than the distance when electromagnetic repulsion and gravity are at equilibrium. The result is an acceleration of your body upwards that is accompanied by a negligible degree of addition gravitational (i.e. accelerated reference frame caused) time dilation. Your angular momentum increases with respect to the earth increases (where your mass*velocity*radius with respect to the earth increases). As you leave the ground, the atoms at and below the surface of the ground begin to return to equilibrium and they regain their original angular momentum with respect to themselves. This must come from some where, which happens to be the lost of your angular momentum, and thus you fall down back to earth.<br /><br /><b>Gravity in the galactic disk</b><br /><br />To explain why galactic rotation curves are flat, all one has to understand that Newton gravity is just a special case of the conservation of angular momentum. To explain a more general theory of gravity, all we need to consider is the conservation of angular momentum. Consider stars of the same mass at some radius R from the galaxy's center of mass traveling at some velocity V. Let's say the R of each star changes. The first star increases its R by x, and the other star decreases its R by x. When the velocities do not change, the angular momentum is still conserved, which can be understood by observing the equation mvr+mvr=2mvr=mv(r+x)+mv(r-x).<br /><br /><b>Gravity in the solar system</b><br /><br />A solar system has fewer orbits than the galaxy and the levels are more discrete and tight than those found in the galaxy. Therefore conservation of angular momentum is largely (though not entirely) confined to individual orbiting particles. A constant angular momentum, mass*velo

 

[richalex]

Gravity is the weakest of the known forces, but it is a cumulative, open-ended force. As someone else pointed out, a small magnet is able to overcome the force of gravity easily. But, magnetic fields generally close into a circuit; magnetic fields don't. It is possible to isolate a magnetic field, but not a gravitational field. So, the force of gravity can accumulate over vast distances.

 

[MeteorWayne]

ROFL, just watched an author explain this to Stephen Colbert.<br /><br />She explained how much stronger magnetism was than gravity <img src="/images/icons/smile.gif" /> <br />(43 orders of magnitude, she said) <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[dryson]

when an object spins at a certain rate of velocity it tends to throw off parts of it's composition in the form of energy. The spinning occures at such a fast rate of velocity that it would create a field around it. The atoms that are spun off from the object either posses the ability to attract, repel or remain neutral in their magnetic fields. When an exact magnetic field of two objects interact with one another then gravity is created. If a magnetic field of an object is immensely greater then another field, then the lower magnetic field will be pulled to the larger field. This release of energy depends on what the elemental composition of each object is comprised of.<br /><br />At the atomic level i would have to surmise that due to the velocity of the neutrons, electrons and protons that orbit the nucleus would interact in the same manner as stated above, otherwise if they didn't then the neutrons, protons and electrons would not be able to mainatain their orbit around the nucleus.

 

[origin]

<font color="yellow">when an object spins at a certain rate of velocity it tends to throw off parts of it's composition in the form of energy.</font><br />It does? Could you give an example.<br /><br /><font color="yellow">The atoms that are spun off from the object either posses the ability to attract, repel or remain neutral in their magnetic fields.</font><br />I guess you are talking about ions that are atoms that are either positively or negatively charged.<br /><br /><font color="yellow">When an exact magnetic field of two objects interact with one another then gravity is created.</font> <br />This statement is totally wrong. Magnetic fields have nothing to do with gravity. Gravity has only to do with mass and is independent of charge. This has been shown to be true experimently.<br /><br /><font color="yellow">If a magnetic field of an object is immensely greater then another field, then the lower magnetic field will be pulled to the larger field. This release of energy depends on what the elemental composition of each object is comprised of.</font><br />If a stonger magnet pulls in a weaker magnet there is no release of energy and the composition of the magnets has nothing to do with any interactions, it is only dependent on the magnetic field strength.<br /><br />Gravity and magnetism are explained quite well in noncalculus based physics books That can be found in your local library. If you have taken any calculus then a college Freshman based physics text book would even have a more in depth expanations. <br /><br />It is good to have a questioning mind and to try to understand the physical world around you - but I suggest learning some physics before you start making your own theories. <div class="Discussion_UserSignature"> </div>

 

[xmo1]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>majornature - Could pressure be what causes gravity??? That depends on how you define pressure. Personally, I look at "gravity" being a byproduct of mass. Then again, mass could be a byproduct of gravity.. It all depends on your view and, ultimately, whether or not we can discover the messenger of mass. It's possible that could happen within a year or so. I'm definitely staying tuned for that one. <br />Posted by a_lost_packet_</DIV></p><p>I think that space-time is not a dimension at all -&nbsp;that space-time and matter-energy are the two&nbsp;elementary components of the universe,&nbsp;that they exist in only three measurable dimensions, and that their existence is co-dependent. One exists because the other exists, and they cannot be separated.</p><p>This answers the question of&nbsp;"What is the universe?" for me.</p><p>It seems to me that any discussion of four or more dimensions can only be&nbsp;an exercise in thought used to explain something.</p> <div class="Discussion_UserSignature"> <p>DenniSys.com</p> </div>