Gravitational mass and Inertial mass

Would you ban me for claiming you are misinterpreting giants of the past, and claiming that the speed of light is constant, and that light is never seen to stop at the EH of a BH, and that your physics, in my opinion is greatly askew?.
Would you ban me for suggesting that if you or any other alternative hypothesis pusher, had anything of substance at all, that invalidated current accepted cosmology, then you would not be here?
And as a moderator, would you continue to disparage and deride the scientific method and peer review?

 

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He had a BA in maths from Cambridge and a physics PhD from Southampton. I think he had a physics MSc from Southampton too, but I'm not sure and a quick check didn't confirm it. As for where he works now, he'd probably prefer it if I didn't say too much. Some people prefer to be private. I think it's a bad idea myself, and that one's conduct is improved by being open about who you are.

I don't think anybody ever had any complaints about his maths. The issues were with his physics.

Oh for God's sake. That's ridiculous naysaying. What the hell do you think the stress-energy-momentum tensor? Or E=mc²?

I'm not wrong. I refer to the likes of Einstein and Baez and Wright and to the hard scientific evidence to back up what I say.

 

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Paddoboy is filtered, but let's see if he's saying anything of interest:

No. But I would ban you if you were abusive and/or dishonest and/or intent on trashing physics discussions threads because you didn't agree with the theme.

I don't disparage and deride the scientific method. Or peer review. I've just pointed out the issues with peer review, wherein "experts in the field" are able to stifle the scientific progress that challenges their expertise. That's the sort of problem we see with rpenner, and saw in the past with Alphanumeric. They see themselves as the experts, and absolutely cannot bear it when somebody shows, quite clearly, that they are wrong. Such self-appointed "experts" sometimes react with outrage rather than civil discourse. And give free rein to abusive trolls, encouraging them to trash discussions when their opponents are winning.

Now, can we talk about gravitational and inertial mass please? I do believe there is a way to explain why they are the same.

 

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[in reference to the startling proof of equivalence, based on F[sub]XY[/sub] = - F[sub]YX[/sub] ]

Oh is that math, Reiku/RealityCheck/Farsight ?? And what grade level did you cover that ? 4th or 5th ?

(Just think back to when you dropped out/flunked out)

And be sure to tell us when you decided the system misjudged you, that you were actually a brilliant physicist.

:roflmao:

F[sub]XY[/sub] = - F[sub]YX[/sub] is a "simple bit of math"

"not that you even understood"

:roflmao:

"troll"

:roflmao:

You won't respond because you can't respond. You never even made it into high school math.

that "simple bit of math"

:roflmao:

We really do need a Comedy Corner for Math & Physics

"Darndest Things Kids Say" - even if you are an old fart, we might as well be arguing with a 4th grader

(with due respect to the kids in grades K-4 who are doing their best.)

:roflmao:

 

Explain.

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This statement confuses me as well.

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What do you mean by find?

What do you mean by indirectly and consistent with (etc.) ?

What does?

You mean principal. But what do you mean by devised?

Do you see this as a kind of duality, such as you might have encountered in some of your courses in Electrical Engineering?

Some of your language is hard to follow. Maybe it would be helpful to give formulas as appropriate to convey what you mean.

 

Since they didn't cover tensors in the 5th grade, I'm sure it is hell for you. But this explains why you aren't sure of the difference between writing

(a) E = mc[sup]2[/sup]

and

(b) E = m∥∥[sup]2[/sup]

and

(c) E ≡ mc[sup]2[/sup]

Problem 2. Explain your statement in the context of (a), (b) and (c).

For a 4th grader maybe. But can you advance through the 5th grade and on to about the 8th grade level where Problem 2 makes sense to you, or to grades 11/12/F where Problem 1 makes sense to you?

No, you rely on quote mining at about the 6th grade level because that's where your language skills dropped off, probably in connection with the wall you hit in math at about the 5th grade.

Still waiting for your answer to Problem 1: Explain the derivative of a function. And (1a) relate this explanation to rpenner's statement local frames are infinitesimal.

Still waiting for you to explain what was defective in the gif you keep posting


Suddenly Farsight goes into overload, throwing calipers left and right and hollering WARNING WILL ROBINSON repeatedly, followed by smoke coming out of his bubble, with these last words, trailing into slo-mo: IT DOES NOT COMPUTE . . .


And then silence.

Hey anybody got a 50 amp fuse?

 

Manifold1: You claim that the equivalence between inertial & gravitational mass has been proven. You show some equations which rely on the equivalence, but which do not prove it.

The equivalence is an observed fact, not a provable relationship. If it were provable, there would be no need for the many experiments designed to measure the degree to which they are the same and/or to look for evidence that they are not equivalent.

As I mentioned in a previous Post, Einstein recognized that the equivalence had deep significance. His thoughts about the equivalence led to General Relativity.

BTW: In the absence of experimental evidence, the scientific community had no reason to assume the equivalence.

 

Why gravitational mass = inertial mass

Imagine you were floating in space. Let's ignore your own mass for now. Some distance away from you is a massive cannonball. This has a non-zero "active gravitational mass". Because of this, you are attracted towards it. You find yourself moving towards it, faster and faster, until eventually you collide with it: ooof. You feel with your poor stomach that it has a non-zero "inertial mass" too.

Now, let's rewind the whole scenario and repeat with a cannonball that's even more massive. You are attracted towards it. You find yourself moving towards it, faster and faster and faster, until eventually you collide with it: oooooof. You feel with your poor stomach that it has a non-zero "inertial mass", and that it has more of it than the previous cannonball.

We can repeat the scenario with any cannonball we like, but you will never find yourself meeting a cannonball that oooooof, turns out to be less massive than you expected. To explore this further however, we need to appreciate that even a photon has a non-zero active gravitational mass and a non-zero inertial mass. This is mentioned in this paper:

"Einstein’s relativity theory appears to be very accurate, but at times equally puzzling. On the one hand, electromagnetic radiation must have zero rest mass in order to propagate at the speed of light, but on the other hand, since it definitely carries momentum and energy, it has non-zero inertial mass. Hence, by the principle of equivalence, it must have non-zero gravitational mass, and so, light must be heavy. In this paper, no new results will be derived, but a possibly surprising perspective on the above paradox is given".

Note that the 't Hooft isn't the Nobel 't Hooft. But this paper is nevertheless right. Look at the last line of Einstein's E=mc² paper: "If the theory corresponds to the facts, radiation conveys inertia between the emitting and absorbing bodies." Light does convey inertia, hence it has a non-zero inertial mass. And it's energy that causes gravity. If you trap a photon in a box, the gravitational field of that box is increased. When you let the photon out, it races away at c, and it has its own gravitational field, albeit slight. Hence it has a non-zero active gravitational mass.

 

Ich denke, in Ihrem Fall, dass "doof" wäre.

 

Besides yourself, who? I am sure there are a few but who they were would say a great deal.

The issue was direct physical observation or evidence that a concentration of energy causes gravity. And so I am clear I am not saying it does not contribute to a gravitational field. I was making the same distiction and challenge concerning an understanding of the difference between what is theoretically accepted and what has been proven, as a function of objective experience... (Imagination and belief, in this situation, does not count as experience.)

 

I don't know what you mean. But see this thread where he and others demonstrated that they didn't know the difference between curved space and curved spacetime. It's not really their fault, it's what they're taught. Wheeler famously said matter tells space how to curve. That's wrong. To be pedantic, the correct version is this: a concentration of energy makes the surrounding space inhomogeneous such that motion through it over time is curved, and we model this as curved spacetime.

Huh? In The Foundation of the General Theory of Relativity on page 185 Einstein said "the energy of the gravitational field shall act gravitatively in the same way as any other kind of energy". A concentration of energy gravitates. A massless photon gravitates. The stress-energy-momentum tensor and E=mc² are not in doubt, relativity is one of the best-tested theories we've got, see http://arxiv.org/abs/1403.7377 .

 

Now that is a great example of hypocritical Irony I must say.

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So you are the expert, who continues to deride the scientific method and peer review, continues to see himself as right and the whole world as wrong....I have not heard you mention your ToE of late...Are you still claiming to have that?

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It isn't hypocritical irony. That's just life. Some guy thinks he's the expert, then I come along, then he spits feathers, then he comes to appreciate that he isn't. And it isn't my ToE. I said years back that the ideas I thought were my ideas, weren't my ideas:

I'm not some my-theory guy. I quote Einstein and others, I refer to the evidence, I give the references, and a sound argument that nobody can overturn. Then you dismiss it all.

 

No, you misquote Einstein and others, and your arguments have been over turned many times.
It's called "delusions of grandeur".

 

http://arxiv.org/PS_cache/gr-qc/pdf/9610/9610066v1.pdf

for some reason, this link didn't quite connect, Farsight.

This paper has some interesting stuff, like on a Planck scale, energy and space are equivalent.

What does anyone else here think of the section "Farewell to Mass"?

One of my colleagues has an expression he produced (by classical means) "maximal acceleration", which was interesting because it actually looks something like the expression given for mass. If the scales weren't so far apart, I'd want to tinker with those ideas. In his SGM model, the Planck length is an idea out to lunch, and about three fries short of a happy meal.

Always looking for better ways of saying the same thing...

 

FAIL. Floating implies no forces acting, which is impossible.

A massless body is acted on by gravity !! Wow -- we really are floating then. Impressive.

:roflmao:

With no mass ??

No, the stomach is massless so it senses nothing. No momentum with zero mass. Here let me do the incredibly hard math for you:

p = m * v
p = 0 * v
p = 0

No momentum, nothing slogging around in the stomach. Nothing exchanged in the collision. Just like it never happened.

No, let's go back and figure out why you want one body to be massless. Because you don't understand basic principles of physics. Everything decouples in Farsight-world. Time warps in his ping-pong GIF, but not space. Here only one body is acted on by gravity, and it's the massless one !!

:roflmao:

FAIL. There can be no force (or pseudoforce) at all without mass. Here let me do the really hard math for you:

F = m * g
F = 0 * g
F = 0

There is no gravity acting on anything per the opening statement. What a dumb cluck attempt to explain classical mechanics. The dropout pretends to teach the faculty. Pure trash.

GAWD more trash for the lower threads..

:roflmao:

While quote mining some permutation on "Noble laureate refutes Einstein" he found a crank. Typical trash.

:roflmao:

What was that you said about a "doof", Dr_Toad ?? 1st person plural is Doof-us ?? Go it.

:roflmao:

Awesome. Radiation pressure can be explained without the need for electromagnetics. That exempts Duffield from yet another subject just way over his head.

Well, we're waiting. If it's not zero, what is the number, Duffield? Just use the standard value for mass and radius of the Earth and give it to us, per photon, at sea level. You can even assume no atmosphere, like in the early Archaean.

The gauntlet has been thrown down. Put up or shut up. Calculate it.



:roflmao:


OOOOF !!!

/roflmao/

Expression given for relativistic mass? Hey, didn't you say you were an Electrical Engineer? Isn't that an important concept in your work, such as in arriving at the propagation speed of signals according to the medium they traverse? So are you speaking in favor of or against Duffield's claim that radiation pressure doesn't have anything to do with electromagnetics? Your posts are hard for me to follow. /confused/

 

I did not read the entire thread, just the page you linked. That said the only thing I saw in the posts of James, Syne, AlphaNumeric and rpenner, that supports your perspective that they were wrong, is that they were quite successfully critiquing your perspective. So again, those who do not agree with you are wrong..?

Remember you were responding to a distiction between proven fact and theory.., and you give as support of your beliefs about reality, a theoretical reference? GR remains a theory... And yes many of the predictions made within the context of GR have proven accurate, but GR still remains a theory. I asked for objective physical experience....

Farsight, again it is my opinion that several other posters have been successfully addressing your beliefs, before and after I joined this discussion. My only real point was and remains clearly separating theory from direct observation and experience... And what appears misinterpretation, perhaps even intentional misinterpretation, of what you find in the words of others. So once more where is there any direct evidence that a concentration of energy causes gravity? And so you don't the wrong idea, I am confident from a theoretical standpoint.., in saying that is likely true, but remains theoretical.

 

No. I've been wrong before, and doubtless I'll be wrong again. But I'm not wrong often, and when I refer to the likes of Einstein and Baez and Wright and Minkowski and Maxwell and the evidence, and others dismiss all that and offer no counterargument, then chances are they're wrong and I'm right. I was certainly right about the distinction between curved space and curved spacetime.

The objective experience is that optical clocks go slower when they're lower, and there ain't no time flowing through them. That should be enough to tell you that yes indeed the speed of light varies with position.

No it isn't, you're just making that up to cling to conviction. If anybody had put up a successful counter-argument you'd refer to it or use it, and you can't.

In the way your pencil falls down. You know your pencil would still fall down if the Earth was made of uranium. And you know about E=mc² from atom bombs. You really are clutching at straws you know. You are clinging to ignorance. You are fooling yourself. Stop doing it.

 

That's what you end up with when you look closely at the photon. That's why gravitational mass and inertial mass are the same. It's like space is some gin-clear ghostly elastic and you use a hypodermic to inject more of the same for the energy-pressure diagonal in the stress-energy-momentum tensor. Then there's a pressure-gradient in the surrounding space, a gravitational field, because you injected a certain amount of energy.

I've got to go out I'm afraid. I'll get back to you later.

 

As JamesR said in Farsight's link, and as Einstein also said, space, spacetime, and the gravitational field, are all one and the same thing.
>>>>>>>>>>>>>>>>>>>>>>>>
This is the single most important question in modern physics. Einstein himself said that so far as his general relativity is concerned, space ( actually space-time) and the gravitational field are the SAME THINGS. We see it as something that is empty because, in modern language, we cannot see the quantum particles called gravitons out of which it is 'manufactured'. We exist much like the raisins in a bread, surrounded by the invisible but almost palpable 'dough' of the gravitational field. In many respects there is no difference between the field that we are embedded in and the apparently solid matter out of which we are made. Even at the level of quarks, over 95 percent of the 'matter' that makes up a 100 kg person is simply locked up in the energy of the gluonic fields out of which protons are fashioned. The rest is a gift from the way quarks and electrons interact with a field called the Higgs field which permeates space. We are, really and truly, simply another form of the gravitational field of the universe, twisted by the Big Bang into a small family of unique particle states.
http://einstein.stanford.edu/content/relativity/a11134.html
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


That is standard acceptable cosmology, and to argue any different, is to indulge in pseudoquackery.