GRAVITY PROBLEMS -- off topic from {Falsifying a young Universe}

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and the talk around E=mc^2 helping perpetuate the horrible myth of nuclear power converting matter into energy in some way. This is one area I like to take the fifth over until I'm satisfied with the understanding of the recipient.

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I just watched a Nova program of Einstein and I heard about 5 physics experts proclaim that matter is converted to energy in nuclear reactions.Why do they keep perpetuating this myth?What is actually going on during fission? Does the nucleus split and all the electrons shift down in energy levels and therefore release large amounts of gamma radiation?And if this is true then why is the mass of the products less than the mass of the reactant?

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I don't need to read it to make that statement. Also, I don't buy the stuff about not being able to explain things unless you throw a good part of your life away!

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You don't need to read anything to make a statement, but reading usually makes statements more informed.

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Exactly why two masses separated in space have a gravitational attraction to one another remains largely unknown, despite much research

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If by "unknown", you mean "known for nearly a century", then I'd have to agree with you.

Fission and Fusion actually involves the weak nuclear force.
Most of the gained energy comes from the atom that remains after fusion requiring less "binding energy".
So the gain in energy doesn't come from converting mass to energy, but from releasing some of the potential energy associated with the force that keeps the atom together.

It's all about a confusion of terminology. There's nothing wrong with these statements if you understand the nature of matter and mass. It's just that very few people do understand these concepts.It is often said that mass/matter has energy. It would be far better to say that energy has mass.Strictly speaking, matter means fermions. Fermions are matter-like in that they are distinct entities and usually their number appears to be conserved.Bosons are not considered matter-like becasue they are not distinct. You can stick as many photons on top of each other as you like, and they blend together. Their number is certainly not conserved. They come and go at will (well, by the rules of QED and QCD!) This makes them more energy-like.But both fermions and bosons have mass by virtue of having energy.So when we say matter to energy, there is an implication of fermions disappearing and photons being released. This happens, it's called matter-antimatter annihilation or simply pair annihilation. An electron and a positron (antimatter electron) can annihilate to produce two photons: matter to energy. The reverse is equally true, energy to matter, and we call this pair creation.The protons in a nucleus are under massive pressure to fly apart by electrostatic repulsion. They are all positively charged... They are bound together by an insane interaction of virtual bosons and fermions. There is huge energy in these particles, and hence mass. If you split the nucleus, this energy is released. You still have the same number of quarks as you started with, but the mass has dropped becasue there is no longer this huge binding energy.So the mass of an atom is the mass of the protons, neutrons and electrons plus the mass of binding energy within the nucleus, plus a little for the mass of the e/m binding energy holding the electrons in place. It is the e/m binding energy that gives rise to chemical energy.The binding energy in the proton or neutron is orders of magnitude larger again. When you think that the mass of a proton is at least 60 times greater than the mass of the three quarks from which it is made! That's rather a lot of binding energy available for your quark bomb!

Simple, if you want to "learn" by reading comments scribbled on the internet, then fine. But don't waste other peoples' time with it. Why do you believe that this site has any authority to make a claim like that?

The claim was that they didn't really know what gravity itself was, but how it worked, exactly, what caused the force. I have seen similar claims elsewhere. Before I go around, correcting a world of sites here, perhaps you could demonstrate we do know this? Or do you when the dust settles, as I supect, agree, but think you have some point that the site I got it wasn't quite up to snuff?Now as far as math goes, remember that after all, it is just numbers!!! You alluded to how it was good in the Lorentz-Fitzgerald contraction thing. Well, so what? It is good in the 2 + 2 = 4 thing as well. But it is pure belief to use numbers for something, say, other than a finite universe, if that was what we had. So, basically, as you get too far away, or too small, etc, all any numbers could be is an extension of your guesses! All fine and good in the box here, where they are meant to work.I could look at the expansion of the universe, and it's rate (someone just told me it has accelerated?)and it's present rate of expansion, come up with some numbers of how long ago it would have been the size of a tiny hot soup, but the numbers are only as good as the belief this is what happened. I don't care if someone spent 27 years learning how to count that high.The link you yourself gave me to check out, similar to what they say about gravity links I've seen, has this to say...
"It is important to realize that in Physics today, we have no
knowledge of what energy is. We do not have a picture that
energy comes in little blobs of a definite amount.
It is not that way."Waiting to see what gravity is, since you hint you know.This message has been edited by simple, 10-13-2005 02:44 PMThis message has been edited by simple, 10-13-2005 02:45 PM

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Now as far as math goes, remember that after all, it is just numbers!!! You alluded to how it was good in the Lorentz-Fitzgerald contraction thing. Well, so what? It is good in the 2 + 2 = 4 thing as well. But it is pure belief to use numbers for something, say, other than a finite universe, if that was what we had. So, basically, as you get too far away, or too small, etc, all any numbers could be is an extension of your guesses! All fine and good in the box here, where they are meant to work.

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That's right, they would be guesses.
That's why we make observations.Besides a theory doesn't have to have infinite applicability to be true.
Newtonian Mechanics is still correct regardless of the fact that it doesn't apply in the Quantum Realm.

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Now as far as math goes, remember that after all, it is just numbers!!!

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That's a very naive view of mathematics(and I'm not being a Platonist).
"It's just numbers" is one of the most overused simplifications of Mathematics and Theoretical Physics I've ever encountered along with "But it's just a theory".

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Waiting to see what gravity is, since you hint you know.

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You see the main problem with this is that you're looking for a mechanism in the everyday sense.
Gravity is very well defined in physics and we certainly know what it is, but like a lot of nature, it's character is mathematical.
Any "word" description will be lacking something, no matter how hard somebody tries.
Tensors, metrics, Manifolds, e.t.c. are the fundamental ideas which express gravity, not any linguistic term.

Nice explanation.What is the bonding energy within the nucleus being converted to? High energy photons? Or is it more accurate to say that these photons were already there and involved in the binding of the protons and neutrons?With regard to your last comment about quarks, is it true that it will never be practically possible to split a proton or neutron? I remember a quote from a book I read a few years back that said something like:"Quarks are what protons would split into, if they could split, but they can't"

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You see the main problem with this is that you're looking for a mechanism in the everyday sense.
Gravity is very well defined in physics and we certainly know what it is, but like a lot of nature, it's character is mathematical.
Any "word" description will be lacking something, no matter how hard somebody tries.
Tensors, metrics, Manifolds, e.t.c. are the fundamental ideas which express gravity, not any linguistic term.

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So, you can't say it, or describe it. But you suggest that we know exactly what it is, and what causes it.
Why does something tell me a lot of your explanation would be theoretical? -If you actually could give one, and aren't just assuming if you stayed in school for another 20 years, you'd know! You say it's character is mathamatical, but what if the character beyond our known physical universe was deeper than that? I really don't believe it, sorry.

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That's right, they would be guesses.
That's why we make observations.

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Besides a theory doesn't have to have infinite applicability to be true.
Newtonian Mechanics is still correct regardless of the fact that it doesn't apply in the Quantum Realm.

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True, of course, just as some theory you may have, or guesses, as you admit here, may very much have limits to it's being true!!!!!!

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That's a very naive view of mathematics(and I'm not being a Platonist).
"It's just numbers" is one of the most overused simplifications of Mathematics and Theoretical Physics I've ever encountered along with "But it's just a theory".

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That isn't my view of mathamatics at all, just to you're trying to project them beyond a physical universe. They can get us very far, but they are not almighty.

simple What he is trying to explain is that the physics of the gravity requires a sufficient background in the mathematics to even have any sense of how gravity manifests.The everyday world is more complex than appears to our limited senses. The world has subtle ways that are not obvious by any other means but mathematics.

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But I realize now that these people were not in science; they didn’t understand it. They didn’t understand technology; they didn’t understand their time.

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physics of the gravity requires a sufficient background in the mathematics to even have any sense of how gravity manifests.The everyday world is more complex than appears to our limited senses.

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But no matter how complicated it may be, or you think it is, a lot of that complication exists as a matter of fact, only inside your heads. This is because, much of the math is directed towards guesses of what is beyond the known. As for the known stuff, which you claim gravity is, totally, I never asked how gravity manifests! That really is pretty simple, we fall to the ground, things attract each other, etc.! The question was, not how the force works, what paths it prefers between 2 objects, do we think it works the same in the quantum level, or etc. Only what is it exactly that causes gravity to exist, and "Exactly why two masses separated in space have a gravitational attraction to one another.."?This message has been edited by simple, 10-14-2005 12:34 AM

simple Not at all. The mathematics is Not guess work but a reliable means of being able to make predictions about the way things work. If the mathematics of the model are correct they will accurately describe a result that can be expected from an experiment.The experiment will reveal value for a given phenomena than can be checked against the predicted value. But you can have no insight into that without having an understanding of the mathematics involved. Without understanding the language nature operates in how do you expect to realize how this really works?Do you understand Quantum mechanics?

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But I realize now that these people were not in science; they didn’t understand it. They didn’t understand technology; they didn’t understand their time.

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Not at all. The mathematics is Not guess work but a reliable means of being able to make predictions about the way things work. If the mathematics of the model are correct they will accurately describe a result that can be expected from an experiment.The experiment will reveal value for a given phenomena than can be checked against the predicted value.

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Only in the limitations of the physical universe. Like Newton's gravity has it's place, so there is a limit to philosophical math. No one doubts it would work here on earth, within it's limits. We can't check whether there is more than a physical universe, we can't know a lot of things. Even some basics, all we know is how they work. Putting guesswork out of the range of normal men doesn't make it less guesswork, only less accessible guesswork.

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But you can have no insight into that without having an understanding of the mathematics involved. Without understanding the language nature operates in how do you expect to realize how this really works?

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I didn't ask for insight into it, just for you to tell us if you could if we know this exactly, and, then, if you could explain it. I also am not convinced nature doesn't speak more than one language!

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Do you understand Quantum mechanics?

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Not much, do you?

And you know this because... And you know this because...You seem to think that you know a great deal about how we do things.

How do I do this other than by telling you that we do know... as well as we know anything else in reality. As I said before, we understand gravity far better than most of the everyday occurances that you experience. You are just not being as demanding of your everyday experiences.Just becasue many people on the web say that we do not understand something does not make it so. How many of them are talking from a position of knowledge? This is difficult stuff... for the vast majority of people, gravity is an unknown. You see, Simple, with this kind of attitude, why do you expect me to bother even writing this reply, never mind a long and detailed explanation of gravity that you may be be able to comprehend? Wasn't me.And anyway, Feynman was lying. He was very good at it. It was how he kept students focussed on their level rather than trying to get ahead of themselves. This is one way that physics is taught. This is where I get unstuck becasue I don't like lying, and I end up trying to explain too much. It is not helpful for the student.