Now that we have our own forum, we can discuss the merits and failures of gravity, on an entirely scientific level.

We need not discuss Magnetism, and various other idiotic mumbo~jumbo, please leave that for OT.

So please, as no theory is water tight, what are the weak points of the gravity theory, and how has it evolved since first proposed?

is gravity a push or a pull. Are we walking on the ground becuse of the stuff above us or the stuff below us ?

is gravity a push or a pull. Are we walking on the ground becuse of the stuff above us or the stuff below us ?

This is actually a good question. I never thought about that.

Here is one intersting question I here often, why is gravity so incredibly weak?

is gravity a push or a pull. Are we walking on the ground becuse of the stuff above us or the stuff below us
Its generally established that the "stuff below us" actually pushes us by warping space-time.

The reason I asked, is I saw the vid that has made me all confused. Mabey gravity isn't the predominant force in the universe. Mabey it's something else. Check Thunderbolts of the Gods (http://video.google.ca/videoplay?docid=4773590301316220374&q=plasma+theory&total=65&start=0&num=10&so=0&type=search&plindex=4)

For some reason I initially read this as "The Scientific Gravy Debate." :crazyeye:

For some reason I initially read this as "The Scientific Gravy Debate." :crazyeye:

That would be interesting, too, as I've never really understood gravy. Now maybe someone should start that thread.

What's the speed of gravity?

What's the speed of gravity?
Same as the speed of light.

But that's only apparent for gravity waves, which have yet to be directly observed.

actually, Intelligent Falling is a much more logical concept, and I demand equal time in schools for it!

is gravity a push or a pull. Are we walking on the ground becuse of the stuff above us or the stuff below us ?

If there were nothing above us, we'd still be walking on the ground. It's a pull.

is gravity a push or a pull. Are we walking on the ground becuse of the stuff above us or the stuff below us ?

"The next question was — what makes planets go around the sun? At the time of Kepler some people answered this problem by saying that there were angels behind them beating their wings and pushing the planets around an orbit. As you will see, the answer is not very far from the truth. The only difference is that the angels sit in a different direction and their wings push inward."

-Richard Feynman

Newton answered the above question by postualting that there was an invisible "tether" of gravity pulling the two together, which is counterbalanced by the Earth's (or any planet's ) forward momentum of the spin, which keeps the planet from falling into the star.

Einstein saw the effects of Gravity by a curvature of space caused by the mass of the sun, and planets kind of "rolling" along the way a marble would over a tablecloth that has dents in certain areas. The best way to test this would be if someone were to remove the sun, it would have an instantaneous effect in Newton's system, but an effect only at the speed of light in Einstein's. All modern physicists seem to agree with Einstein's model, but I have yet to see (or see and understand) an experimental model as to why this must be so.

My question is this. A guy in a spaceship is said to be "weightless". It's not actually true. He is falling at the same rate and direction that his container is falling, and so appears to hover over the floor. But he does have mass, and it does impact his motions. What happens if you really remove all gravity from an area, (in Einstein talk, you flatten the normal curvature of space) that an object moves in?

Same as when you are 'weightless'.

My question is this. A guy in a spaceship is said to be "weightless". It's not actually true. He is falling at the same rate and direction that his container is falling, and so appears to hover over the floor. But he does have mass, and it does impact his motions. What happens if you really remove all gravity from an area, (in Einstein talk, you flatten the normal curvature of space) that an object moves in?
The object doean't move (unless of course its using some other force to move). However, the object can have an affect upon itself due to gravity. Take for example, the sun who basically is in a flat plane that is only contorted by itself (sure the planets do have an affect on the sun, but its slight enough that it doesn't matter). It is so massive that the particles at its core undergo a fusion reaction which has an important affect of sustaining the itself.

My question still remains though, why is gravity so weak that my miniscule little arm can lift objects that the Earth that weighs trillion upon trillions of tons is pulling down.

Because it is?

Because it is?
But why is it so weak? Are you saying there is no reason?

Because compared to some others, (like electromagnetism) gravity is pathetically weak. It only manages to play a major role in solar system creation and the like because there are no real opposing forces. Many cosmic dust clouds will remain in their current state indefinitely without some outside stimulus, because even though gravity ought to make the cloud contract, the slight heating effect caused by that condensation pushes the gas molecules back out and keeps the cloud from contracting.

EDIT- In response to Greenpeace, it is unclear at this moment exactly what Gravity is, or what causes the attractive force. Until such time, it is really impossible to answer "Why is it weak?" and I can only really say that I can measure the force of attraction in regard to the masses of the object sand the distance between them

As for my above question. I do not think that an object moving in zero gravity (and I should have made that clearer, sorry.) ought to be subject to the same rules that apply when miniscule amounts of gravity are in effect. Whena guy is in orbit, he falls along a certain channel, and so does the spaceship with him, hence, hovering.

I'm talking about you have an object, that is moving across a stretch of the universe that has been pounded flat. You have 0 amonts of any outside forces acting upon it. Would the normal laws of motion even apply to it? (since I doubt Newton could even consider motion in a place without gravity)

As for my above question. I do not think that an object moving in zero gravity (and I should have made that clearer, sorry.) ought to be subject to the same rules that apply when miniscule amounts of gravity are in effect. Whena guy is in orbit, he falls along a certain channel, and so does the spaceship with him, hence, hovering.

I'm talking about you have an object, that is moving across a stretch of the universe that has been pounded flat. You have 0 amonts of any outside forces acting upon it. Would the normal laws of motion even apply to it? (since I doubt Newton could even consider motion in a place without gravity)
Gravity is just a force that potentially pulls objects with mass together. It is just as vital to motion as any other force. There is no reason that just because there is no gravity doesn't mean that pushing something will make both of you fly apart.
Of course, it is true that motion would be different since objects wouldn't be pulling each other together, put all the other forces would remain just as strong.

I thought that the difficulty of "understanding" gravity is, that it's affects are instant - and not restricted by the speed of light.
So works in "real time" so to speak. Or have I misunderstood current knowledge about gravity?

I thought that the difficulty of "understanding" gravity is, that it's affects are instant - and not restricted by the speed of light.
So works in "real time" so to speak. Or have I misunderstood current knowledge about gravity?
Gravity's affects are just like everything else in that it doesn't operate faster than the speed of light (except teleportation, which BTW is real and has happened in labs).

Gravity's affects are just like everything else in that it doesn't operate faster than the speed of light (except teleportation, which BTW is real and has happened in labs).Teleportation also happens at sub light speeds. Quantum teleportation isn't about disappearing from one place and reappearing at another distant place in the same instant. It has more to do with the ability of particles to appear on the other side of a classically impassible barrier from time to time. In other words its about passing through walls.

But why is it so weak? Are you saying there is no reason?


EDIT- In response to Greenpeace, it is unclear at this moment exactly what Gravity is, or what causes the attractive force. Until such time, it is really impossible to answer "Why is it weak?" and I can only really say that I can measure the force of attraction in regard to the masses of the object sand the distance between themThat's not quote right. Einstein's theory of gravity does plenty to describe what gravity is. The strength of gravity is a build in constant in his equations. From that perspective there is no special reason why gravity is as weak as it is.

The trouble with Einstein's theory is that is that it is incompatible with quantum theory, which is currently used to describe the other fundamental forces. Both theories need to be modified somehow so that the two make sense. Scientist hope that this revised theory of everything will provide more insight into why gravity is so weak, or possible claim that gravity is not so weak at higher temperatures/densities. This could mean greater symmetry between the fundamental forces. Current models say that the other three forces have a temperature/density at which they all have approximately the same intensity. But gravity is the odd one out. Scientists want to know the reason for this asymmetry, and hope that it's not really an asymmetry at all.

Teleportation also happens at sub light speeds. Quantum teleportation isn't about disappearing from one place and reappearing at another distant place in the same instant. It has more to do with the ability of particles to appear on the other side of a classically impassible barrier from time to time. In other words its about passing through walls.
Actually it does happen at faster than the speed of light. Here is an easy example of a kind of information teleportation:
Lets say I have one electron spinning up and one down and I send them off in opposite directions. Lets say and arbitrary amount of time laters, I observe whether the electron I have is spinning up or down. When I observe whether or not its spinning up or down, I instantly know whether or not the other electron is spinning up or down. That means faster than the speed of light I can tell information regarding an object.

In terms of teleportation, physicist have used this by havinf a similar set up with three particles (at first it was photons because they are easiest). I have photons A, B, and C. A and C are set up just like the above example such that if one is a certain state the other has to be in the same (well in the previous example it was different, but whatever). Then the information in photon B was transferred to A, which then made C change to be B. Thus B teleported to location C faster than the speed of light.

Actually it does happen at faster than the speed of light. Here is an easy example of a kind of information teleportation:
Lets say I have one electron spinning up and one down and I send them off in opposite directions and the speed of light. Lets say and arbitrary amount of time laters, I observe whether the electron I have is spinning up or down. When I observe whether or not its spinning up or down, I instantly know whether or not the other electron is spinning up or down. That means faster than the speed of light I can tell information regarding an object.

In terms of teleportation, physicist have used this by havinf a similar set up with three particles (at first it was photons because they are easiest). I have photons A, B, and C. A and C are set up just like the above example such that if one is a certain state the other has to be in the same (well in the previous example it was different, but whatever). Then the information in photon B was transferred to A, which then made C change to be B. Thus B teleported to location C faster than the speed of light.Ok, you're talking about quantum entanglement. I though you were talking about quantum tunneling. That's why scientists don't use teleportation as a technical term. Yes, entanglement does involve information traveling faster than light.

Aside: electrons can't travel at the speed of light. Not for long distances anyway. They have mass.

All modern physicists seem to agree with Einstein's model, but I have yet to see (or see and understand) an experimental model as to why this must be so.?

I'm no expert on the subject (yet), but I believe I can answer that one. One of the big confirmations of Einstein's model was related to the way that light behaves under gravitational influence. In Newton's model, gravity is just a force that spontaneously arises between two particles, and the magnitude of that force is just based on their masses. Thus, the photon, a massless particle, would not be affected by gravity in Newton's model.

However, in Einstein's model, photons are still influenced by the curvature of space-time, so we should be able to observe this phenomenon. In fact, the planet Mercury was observed to apparently change its position due to this "gravitational lensing" during an eclipse, and there are lots of other cool effects that can be seen due to this.

That's just one of the confirmations, but it's the one I'm most familiar with.

Aside: electrons can't travel at the speed of light. Not for long distances anyway. They have mass.
Actually as long as they are not in the same position, it doesn't matter how fast they are moving.

Ok, you're talking about quantum entanglement. I though you were talking about quantum tunneling. That's why scientists don't use teleportation as a technical term. Yes, entanglement does involve information traveling faster than light.

Aside: electrons can't travel at the speed of light. Not for long distances anyway. They have mass.

Actually there is no real information traveling in this case. The wave-function collapses faster than light, but the wave-function is not anything tangible.

And for certain applications (like this one) one can say that electrons travel at the speed of light. Sure they cannot exactly reach it, but close enough that the difference is neglible for certain applications.

Actually as long as they are not in the same position, it doesn't matter how fast they are moving.They still can't move faster than light for long distances. The average speed of an electron is always less than the speed of light. Uppi's right that the speed can be just slightly smaller. It's just there no reason to say "at the speed of light" when "near the speed of light" is just as easy to say and is more accurate.
Actually there is no real information traveling in this case. The wave-function collapses faster than light, but the wave-function is not anything tangible.There's the information of the collapsed wave function. The second particle knows that the other particle has been observed and the result of the observation. Yes, I know that isn't usable information, but it's information all the same.

They still can't move faster than light for long distances. The average speed of an electron is always less than the speed of light. Uppi's right that the speed can be just slightly smaller. It's just there no reason to say "at the speed of light" when "near the speed of light" is just as easy to say and is more accurate.
I know, I know I'm just saying the speed doesn't matter, and if I feel like it I'll edit the post.

It's just as easy to interpret those results (the instantaneous wave-function collapse stinks of the Copenhagen Interpretation) as you simply not being able to tell what state the 'entangled' particles are in until you look. Hey presto they are in a pair of states. Amazing. There is no evidence that they were not in that pair of states all along and therefore no evidence of instantaneous information transfer.

G could easily be different in other universes.

They still can't move faster than light for long distances. The average speed of an electron is always less than the speed of light. Uppi's right that the speed can be just slightly smaller. It's just there no reason to say "at the speed of light" when "near the speed of light" is just as easy to say and is more accurate.

it's technically more correct, but it's not more useful in some cases. In physics you always have to find a balance between technical correctness and usefulness.


There's the information of the collapsed wave function. The second particle knows that the other particle has been observed and the result of the observation. Yes, I know that isn't usable information, but it's information all the same.

Really depends on how you define "information". If you define information as something that can be observed, then there is no information traveling, as quantum teleportation only works if you know that it has been observed on the other side. Of course if you define information somehow in relation to the particle then you could say information is traveling (but again it's not a very useful definition)

It's just as easy to interpret those results (the instantaneous wave-function collapse stinks of the Copenhagen Interpretation) as you simply not being able to tell what state the 'entangled' particles are in until you look. Hey presto they are in a pair of states. Amazing. There is no evidence that they were not in that pair of states all along and therefore no evidence of instantaneous information transfer.


The hidden variables interpretation sounds like it could solve our problems with quantum mechanics, however it is contradicted by experiment.

G could easily be different in other universes.

The "easily" really depends on the "true" (if there is such a thing) theory of gravity and if G is a free variable or somehow determined by other factors in that theory. (And of course one has to accept multiple universes in the first place.)

wtf, You thought I was rooting for hidden variables?!?!?!

Not on a cold day in Hell my friend.

Just that the actual state of the entangled pair cannot be determined except by observation. It's all well and good claiming the waveform is collapsing when you do this and claiming simultaneity, but all that is actually happening is that you are seeing which of the potential possibilities already happened.

wtf, You thought I was rooting for hidden variables?!?!?!

Not on a cold day in Hell my friend.

Just that the actual state of the entangled pair cannot be determined except by observation. It's all well and good claiming the waveform is collapsing when you do this and claiming simultaneity, but all that is actually happening is that you are seeing which of the potential possibilities already happened.

And when exactly has that happened? And how to you explain the fact, that it makes a difference if it is measured at the other end or not? If it is already decided which of the potential possibilities happened then the measurement at the other end should have no impact on this end of any kind.

If you're no friend of the standard Copenhagen interpretation, what interpretation do you prefer?

Many Worlds.

Where is it proven that the measurement makes a difference? You have made your particle pair either A/B or B/A. All you are doing is finding out which configuration they are actually in.

Many Worlds.

Where is it proven that the measurement makes a difference? You have made your particle pair either A/B or B/A. All you are doing is finding out which configuration they are actually in.

It is the whole point of quantum teleportation or the EPR-paradox, that it does make a difference.
http://en.wikipedia.org/wiki/EPR_Paradox

The spin measurement doesn't just give two states A and B, but two states relative to one of the three axis. Whichever of the axis is chosen at one end has consequences on the statistics on the other end.

And the in many worlds interpretation there is no predetermined state, the possibilities are interpreted as different worlds that are still both valid. The measurement is interpreted not as wave function collapse but decoherence of these worlds. And this happends faster than light, whether you interpret it as wave function collapse or decoherence.

I think your interpretation of this is highly debateable...

Err, no information is transfered faster than the speed of light in the EPR paradox. "Information" in this context is something useful to the observer -- something that, if transmitted instantaneously, would violate causality. Causality is not necessarily violated by non-locality; the Copenhagen Interpretation is non-local, and doesn't violate causality.

My question still remains though, why is gravity so weak that my miniscule little arm can lift objects that the Earth that weighs trillion upon trillions of tons is pulling down.

Because if it couldn't, you wouldn't be here to ask that question.

(Of course there could be some other thinking creatures, but they would be asking other questions, like "why is gravity so strong?")

Because if it couldn't, you wouldn't be here to ask that question.

(Of course there could be some other thinking creatures, but they would be asking other questions, like "why is gravity so strong?")
You misunderstand the question, its wasn't about biology it was about how extremely weak the force of gravity is compared to the other forces.

You misunderstand the question, its wasn't about biology it was about how extremely weak the force of gravity is compared to the other forces.
He's refering to the Anthropic Principle (http://en.wikipedia.org/wiki/Anthropic_principle).

EDIT: Thinking about it, he might not be refering to that, but you should look it up anyway.

He's refering to the Anthropic Principle (http://en.wikipedia.org/wiki/Anthropic_principle).

EDIT: Thinking about it, he might not be refering to that, but you should look it up anyway.
Well I'm pretty sure he is referring to that, but I'm saying it doesn't answer the question.

What makes you think there is a reason why G has the value it does?

is gravity a push or a pull. Are we walking on the ground becuse of the stuff above us or the stuff below us ?

I would say gravity is a pull from the Earth's core. The alternative is a push from the atmosphere, but let's face it -- if that were true, wouldn't we have differences in our weight based on altitude? Then again, atmospheric pressure would similate a similar effect...

Gravity is what we call the curvature of space-time by a mass.

[6 -year question mode]And why do space time curve in the presence of a mass? The curvature changes can exceed the speed of light? Are you talking about inertial or gravitational mass? What is a mass anyway?[/6 -year question mode]

[6 -year question mode]And why do space time curve in the presence of a mass? Because they do. The curvature changes can exceed the speed of light? Can it? Are you talking about inertial or gravitational mass? Is there a difference? What is a mass anyway? A major concentration of energy.[/6 -year question mode]
Long time no see Col.

And why do space time curve in the presence of a mass? Because they do. Dogmatic awnser... please insert valid reason
The curvature changes can exceed the speed of light? Can it? Actually they can... waves in a fluid can exceed the maximum speed of the particles in that fluid...
Are you talking about inertial or gravitational mass? Is there a difference? Yes, there is... inertial mass is a constant that measures the resistance of a object to accelerations.... gravitational mass is a constant that represents the force needed to resist the attraction from another object. They aren't the same stuff: we only assume them the same because of convinience
What is a mass anyway? A major concentration of energy Not exactly... vacuum has far more energy than matter ( otherwise how could the spontaneous ( and somewhat rare ) pairs of particle anti particle to appear near the black holes and account for their radiation ( Hawkings theory ) ? ) and does not have gravitational effects

Dogmatic awnser... please insert valid reasonBetter refutation required first. All i've done is (re)state a fact, please explain why that fact needs an explanation.
Actually they can... waves in a fluid can exceed the maximum speed of the particles in that fluid... ...and evidence that gravitational waves travel faster than c comes from what source precisely? And what makes you think the analogy is valid in the first place?
Yes, there is... inertial mass is a constant that measures the resistance of a object to accelerations.... gravitational mass is a constant that represents the force needed to resist the attraction from another object. They aren't the same stuff: we only assume them the same because of convinienceYou are claiming a dichotomy. I claim a coincidence. You have evidence that these things are necessarily different?
Not exactly... vacuum has far more energy than matter ( otherwise how could the spontaneous ( and somewhat rare ) pairs of particle anti particle to appear near the black holes and account for their radiation ( Hawkings theory ) ? ) and does not have gravitational effectsProof please. AFAIK vacuum energy is not very high.

Better refutation required first. All i've done is (re)state a fact, please explain why that fact needs an explanation.[/COLOR]
Fact? You're restating a interpertation of the Restricted Relativity Theory and ,as much as you can provide basis to a theory, it never becomes a fact because of that ( you can be seeing all lopsided ). Popper dixit
...and evidence that gravitational waves travel faster than c comes from what source precisely? And what makes you think the analogy is valid in the first place?
The math treatment of your proprosed theory implies that the time space contuinuum can be treated like a fluid
You are claiming a dichotomy. I claim a coincidence. You have evidence that these things are necessarily different?[/COLOR]
No... but that is exactly the same ammount of evidence you have that they are the same ( or even somehow related ).
Proof please. AFAIK vacuum energy is not very high.
Will try to find Dirac calculations.

Fact? You're restating a interpertation of the Restricted Relativity Theory and ,as much as you can provide basis to a theory, it never becomes a fact because of that ( you can be seeing all lopsided ). Popper dixitI've never heard of 'Restricted Relativity' - do you mean Special Relativity, as opposed to General Relativity?

All the theory does is provide a mathematical description of the shape space adopts around concentrations of mass and energy. Why does space curve around these concentrations? For the same reason Electrons are associated with an electric field and G has the value it does: Because that's the way the universe works.
The math treatment of your proprosed theory implies that the time space contuinuum can be treated like a fluid Why?
No... but that is exactly the same ammount of evidence you have that they are the same ( or even somehow related ). What more evidence do you need than that 'm' appears in both sets of equations?

Inertial mass and gravitational mass have been shown to be the same thing under General Relativity. Previously, they were two separate (but numerically identical) things; GR showed that they are the same. So far, we've discovered no object that is, for example, extremely easy to push, yet exhibits a very high gravitation force. GR reinforces that by providing a theoretical framework in which inertial mass and gravitational mass are required to be the same thing, in order for physics to work, rather than it just being shear coincidence.

Actually they can... waves in a fluid can exceed the maximum speed of the particles in that fluid...
I have no idea why this is relevant to GR. But you should be clear on what you mean by "wave" and "particle". You seem to be likening the propagation of forces via waves to the propagation of, for example, waves on the ocean or sound waves. That's not how it works...

In addition, if curvatures in spacetime could change faster than the speed of light, it would mean that information can travel faster than the speed of light, which would put GR at odds with SR... Given that both are (a) internally consistent, and (b) consistent with one-another, this seems unlikely...

Well I'm pretty sure he is referring to that, but I'm saying it doesn't answer the question.
Explain to me why you think it doesn't answer your question and I'll explain to you why you're wrong :p :)

Explain to me why you think it doesn't answer your question and I'll explain to you why you're wrong :p :)
I asked why is gravity weak and you said humans adapted to be efficient at working with Earth'd gravity, but the evolution of people has no affect on the strength of gravity.

I asked why is gravity weak and you said humans adapted to be efficient at working with Earth'd gravity, but the evolution of people has no affect on the strength of gravity.
It's the other way around. The universe is fine tuned by a number of constants that determine, for example, the strength of fundamental forces. The anthropic principle states that, when looking at these constants, we should only concern ourselves with values for the constants that support human life. There aren't many possible combinations of values that can lead to human life; if Gravity was stronger, humans would not be here to observe that Gravity was stronger.

I asked why is gravity weak and you said humans adapted to be efficient at working with Earth'd gravity, but the evolution of people has no affect on the strength of gravity.

Suppose that gravity was so strong that you couldn't lift anything from earth (your own example): human life wouldn't be possible, and you wouldn't exist.

Well, there could be maybe some stronger species, which could lift something, but then they would be asking: "Why is gravity so weak?"

Only case that I can think of, where this question wouldn't be asked, were if there would be plant-like thinking creatures, which could not lift anything from earth. They would be asking "why is gravity so strong" instead.

It's like if you asked: "Why was I born in San Fransisco, the chances are just about one in 10 000? Why wasn't I born in New York?": If you were born in New York, you would be asking "Why was I born here, chances are just about one in 600?"

But why must we exist? Answer: we don't have to, so the constant of gravity could be something else. Why this one?

Didn't you guys read that book "Just 6 Numbers" by Rees? The whole book is about nothing other than this stuff: why the constants of nature are the values they are, and the implications thereof.

No need discussing this further until you've all read it ;)

I asked why is gravity weak and you said humans adapted to be efficient at working with Earth's gravity, but the evolution of people has no affect on the strength of gravity.
But the strength of Earth's gravity has an effect on how humans adapt to living on it.

But the strength of Earth's gravity has an effect on how humans adapt to living on it.
Yeah, but it doesn't explain gravities' weakness. You'd have to have a really big nose to not see that
(note to everyone except Drtad, that line is a meme between us :) )

But why must we exist? Answer: we don't have to, so the constant of gravity could be something else. Why this one?
We don't have to exist -- gravity could easily be such that humans could never survive. It could be such that no living thing could survive. There could be another universe in which this is true. But we're not in that universe, we're in a universe in which humans exist. If you don't want to assume that humans exist, then I think you're talking a different language to the rest of us ;)

At its core, I don't know why this is such a big deal. Gravity is a weak force, but so is magnetism when compared with electricity -- and they're the same force!

Yeah, but it doesn't explain gravities' weakness.
Well, since we aren't entirely sure why gravity exists at all, we aren't in a position to say why it is a weak force.

You'd have to have a really big nose to not see that
(note to everyone except Drtad, that line is a meme between us :) )
My nose is not that big!:rolleyes:

Well, since we aren't entirely sure why gravity exists at all, we aren't in a position to say why it is a weak force.
Is it possible to find out?

My nose is not that big!:rolleyes:
Then why is the rest of your body pale?

At its core, I don't know why this is such a big deal. Gravity is a weak force, but so is magnetism when compared with electricity -- and they're the same force!Its a matter of symmetry. The other three forces relatively similar in strength, when compared to gravity. Furthermore, during the early universe they are said to have been almost equal in strength, all intersecting at nearby density levels, where as the formula for gravity imply that it was always relatively week.

We don't have to exist -- gravity could easily be such that humans could never survive. It could be such that no living thing could survive. There could be another universe in which this is true. But we're not in that universe, we're in a universe in which humans exist. If you don't want to assume that humans exist, then I think you're talking a different language to the rest of us ;)

At its core, I don't know why this is such a big deal. Gravity is a weak force, but so is magnetism when compared with electricity -- and they're the same force!
Ok, that makes sense if there are multiple universes.

Is it possible to find out?
Well, it's possible for me to find out.:p

Then why is the rest of your body pale?
Okay, now you lost me. But my nose is still not overly large!:crazyeye:

Okay, now you lost me. But my nose is still not overly large!:crazyeye:


Well, it's possible for me to find out.:p
If your nose isn't that large, how is it you know so much about gravity?

If your nose isn't that large, how is it you know so much about gravity?

I have ways.:jesus:

:lol:

But anyway, it seems as though we can't find out about gravity unless we discover the intricacies of things like mass and charge first.

I have ways.:jesus:

:lol:

But anyway, it seems as though we can't find out about gravity unless we discover the intricacies of things like mass and charge first.
Well, we can rather accurately predict its affect.

Well, we can rather accurately predict its affect.
Yes, but we don't know anything about why.

You would think that the mass of a proton would increase if combined with an electron. That's wrong, the mass of the whole thing drastically decreases. Why? Nobody knows (yet).

Why do objects pull each other (gravity)? Don't know. We just know that it exists and can predict its effects.

The modern understanding of Gravity is that it is just a curvatur of space.

Quantum mechanics and Gravity(general relativity) haven't yet been able to unify, so can't combine the small effect of the Quantum world with gravitational effects.

The effects of gravity works with the speed of light, so a body orbiting an other one produces gravitational waves.

The most interessting fact about Gravity is that you can't measure it without the help of an other force(usally electromagnetism, but could be also the strong or the weak force). So in a world where there only is gravity and no other force you can't measure for example distances, you can only give a topological arrangemnt of masses.

You would think that the mass of a proton would increase if combined with an electron. That's wrong, the mass of the whole thing drastically decreases. Why? Nobody knows (yet).


:confused: What makes you think that? You must live in universe very different from ours...

Ok, that makes sense if there are multiple universes.

I don't think it requires there to actually be multiple universes, just that the possibility that "a universe"/"the universe" could be set up in a different way exists. The universe, of course, actually is set up s.t. gravity is really really weak.

:confused: What makes you think that? You must live in universe very different from ours...
Err, I am sorry if I worded that incorrectly, but it was something my physics teacher said. I may have remembered incorrectly but it was something similar to that...

Err, I am sorry if I worded that incorrectly, but it was something my physics teacher said. I may have remembered incorrectly but it was something similar to that...

Then either you indeed remember incorrectly or your teacher said something wrong. Depending on the meaning of "combine" you get either a hydrogen atom or a neutron. The hydrogen atom has the mass of proton and electron combined (minus the binding energy of 13.6eV, which is tiny in comparison). The neutron is also heavier than the proton (if I remember correctly it is 939MeV compared to 938MeV for the proton, so the difference is even larger than the mass of the electron).

If a process releases a lot of energy, the mass of the products will certainly be smaller than the initial particles, but this is well understood with as equivalence of mass and energy.

I don't think it requires there to actually be multiple universes, just that the possibility that "a universe"/"the universe" could be set up in a different way exists. The universe, of course, actually is set up s.t. gravity is really really weak.
Of course (since their logically equivelent in this case).