# A Few Questions Concerning Inertia

Discussion in 'Physics & Math' started by gluon, Feb 18, 2009.

1. ### AlphaNumericFully ionizedRegistered Senior Member

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The Planck time is NOT infinitesimal. Infinitesimal is defined as 'smaller than any Real number'. The Planck time is not smaller than any Real number, because its a Real number.

And the Planck mass is small by human scales but on particle physics scales its staggeringly enormous.
Using a set of scales to weigh out a mole of substance does use G, but it doesn't have to. Mass is not defined by weight but its inertia. 12g of Carbon can be measured out in a weightless environment. It's just convenient to use weight when you're on the Earth's surface doing practical things. The Planck mass has nothing to do with N_A, you need absolutely zero knowledge of N_A to work with the Planck mass.

Yet again, you stumble through a bunch of concepts obviously a little too advanced for you.

3. ### VkothiiBannedBanned

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Well, it looks like it's all over apart from a few parting bashes over the head with various accusations.
I'd like to accuse D H of pedantic linguistic point-scoring, following his parting smack between the eyes with that last lot, and I proffer the following rebuttal:
Your poor grasp of the English language is apparent; there is supposed to be "a smallest" mass described in terms of h.

Except if you gauge it with G (which is for large numbers), there is "a" problem isn't there?

And look, our local expert has confirmed that Planck mass "has nothing to do with N_A"

So using G, is inappropriate; please use a different gauge.
And thankyou again for your patience.
(the management)

Perhaps you can get all excited deciphering: "the large gauge G is inappropriate for a small number h; since it can't accurately select the absolutely smallest mass available.
Therefore Planck mass in Newtonian terms is only approximately the smallest value for any m, and so is only a "smallest" value that G can gauge, when there are smaller than this smallest width, than G can actually measure"

There is a problem here; the problem is: "the smallest we can measure with G(m)" is not "the actually smallest in the quantum domain where h gauges m", so is at best "a smallest available" in the non-Avogadrian domain.

(the management)

Last edited: Feb 26, 2009

5. ### D HSome other guyValued Senior Member

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G has nothing to do with Avogadro's number, either, Vkothii.

7. ### AlphaNumericFully ionizedRegistered Senior Member

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When someone says "h gauges m" in the same sentence as the word 'quantum', I immediately think "How does h provide a gauge transformation to m, neither of them are fields".

In Newtonian terms there is no smallest mass, because Newton didn't view the world using quantum mechanics, but saw everything as a continuum. In quantum mechanics you cannot break down a fluid as much as you like, there's elementary particles. Newtonian views are that no matter how much you break down a substance, you can do it some more, so there's no 'quantum of mass' in Newtonian physics. There's no 'quantum' of anything really. This can be further seen by viewing Newtonian physics as the $\hbar \to 0$, $c \to \infty$ limit of quantum field theory, giving a zero Planck mass so even if the Planck mass were a quantum of mass, its zero in Newtonian physics.

Vkothii, there is nothing wrong with using G in relativity or quantum mechanics. It is required so that more advanced theories limit to the Newtonian classical case, as we know they must in low energy or large distance limits (which come down to the two limits I just mentioned). When you derive the Einstein Field Equations and/or the Schwarzchild metric you find that in order for you to get the right behaviour your integration constants must be such that G is in there somewhere. It's not a new concept to say "I define this quantity at this energy scale, even though I work at this energy scale". Quantum field theory does it all the time. When you look up things like the couplings between various particles you are told the value at a particular energy, because you can then use the equations of quantum field theory to work out the coupling at the energy you're interested at. Dynamical energy scales and varying 'constants' is all part and parcel of particle physics.

You're whining at us because you don't know this and don't like being told you don't know.

8. ### VkothiiBannedBanned

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G "has nothing to do with Avogadro's number"??
Can you derive a value for either independently, to support your claim?

Guess what: I know there's "nothing wrong with using G" in any frame; except for all the problems with calculating the energy in spacetime.
Apparently the constants we use yield a value which is "embarrasing" (although hardly anyone, unlike me, whines about it).
Last I heard, the gap was about 120 zeros wide.

As the string theorists say, you can use coupling interactions instead; nonetheless there is no way to scale these to G or gravity's constant.

IF h is "the smallest" anything; it gauges anything small (maybe anything big too). Since h is apparently the smallest - energy, length, mass etc. Unless mass is "h-less"; but this does not appear to be the case, all mass quanta have spin we are told, therefore "h gauges mass" - we might not know how it does, but we know that it does. Unless there are 'spinless' quanta with mass. Maybe so, who knows?

Last edited: Feb 26, 2009
9. ### D HSome other guyValued Senior Member

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G has nothing to do with Avogadro's number.

Newtonian constant of gravitation (G)
Value: 6.67428x10[sup]-11[/sup] m[sup]3[/sup] kg[sup]-1[/sup] s[sup]-2[/sup]
Relative standard uncertainty: 1.0x10[sup]-4[/sup]​
Value: 6.02214179x10[sup]23[/sup] mol[sup]-1[/sup]
Relative standard uncertainty: 5.0x10[sup]-8[/sup]​
Correlation coefficient r of the above two quantities: r = 0.0000

G has nothing to do with any other fundamental physical constants, so far as we know; that theory is yet to be developed. (G obviously has a lot to do with the Planck mass m[sub]P[/sub]; the Planck mass is a derived rather than fundamental physical constant.)

From page 56 of http://physics.nist.gov/cuu/Constants/codata.pdf
X. NEWTONIAN CONSTANT OF GRAVITATION G
Because there is no known quantitative theoretical relationship between the Newtonian constant of gravitation G and other fundamental constants, and because the currently available experimental values of G are independent of all of the other data relevant to the 2006 adjustment, these experimental values contribute only to the determination of the 2006 recommended value of G and can be considered independently from the other data.

Last edited: Feb 26, 2009
10. ### gluonBannedBanned

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''G has nothing to do with any other fundamental physical constants, so far as we know; that theory is yet to be developed. (G obviously has a lot to do with the Planck mass mP; the Planck mass is a derived rather than fundamental physical constant.)''

Is that why you ignored my post?

11. ### VkothiiBannedBanned

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See how Newton's constant is a property of large masses, with an independent number of atoms, which we measure with molar scales (like weighing balances).

We can't prove that G and Avogadro are completely independent, because we use Avogadro's number of atoms to calculate G; their independence is actually a simple foreground/background effect.

Fundamentally if N_A of independent atoms measures G, this depends on G and N_A, or if N_A, then G.

12. ### gluonBannedBanned

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Did anyone here know, that no one knows how Newton derived the constant G?

13. ### AlphaNumericFully ionizedRegistered Senior Member

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Use any equation which involves G but no N_a, which is pretty much all of them, because if you know all the other quantities in the equation, you can find G. There's no bound on the masses or energies when you're using things like the Einstein Field Equations other than staying above the Planck length, in terms of energy, which is easy because its all we're capable of. As DH's link and many more will explain, we've done many high precision measurements of G. Yes, in general we use large quantities of matter to do that but that's because G is small so you need a lot of matter to get an effect. We don't need to know how many moles of substance are in the Earth to know its mass. And once we know its mass we can get G by simply weighing objects.

G requires us to know masses, not quantities.
That is nothing to do with our choice of units, it is to do with the fundamental difference between quantum field theory and general relativity. Quantum field theory doesn't count the energy of space-time proper, because it doesn't treat gravity as a quantum field properly, general relativity does treat gravity properly over large distances. So when you try to model something like the cosmological constant, the intrinsic energy of space-time usiing a non-quantum gravity field theory you get a wrong answer. A very wrong answer.

It's not because we're using G, but because when you naively try to quantise general relativity you find graviton self interactions spiral out of control and basically give everything, even the empty universe, a hinking huge mass. The fact this mass is pretty much the Planck mass is simply a rephrasing of "The energy level of quantum gravity is the Planck mass", just as when you break electroweak symmetry the W and Z bosons are around 90GeV, that's the electroweak scale.

Nothing to do wiith units, everytning to do with the fundamental non-renormalisability of gravity in 3+1 dimensions. Which I'm sure is beyond your comprehension. No matter how many sigma Lie algebra lecture notes you're looked at.
Hang on, let me check something....

....

Yeah, I am doing a PhD in supersymmetric gravity models, which includes Planck scale physics. For a moment I thought I wasn't because what you say doesn't square up with what I do.

Tell me, do you know about running couplings? Effective couplings? The relationship between the Planck scale and dimensions? Or with compact dimensions? I doubt it, so stop trying to make claims about an area you don't work in and clearly don't understand.
Who said h was the smallest anything? Firstly, its not a length, energy or mass. Secondly, jsut because light comes in integer multiples of it doesn't mean nothing else can be smaller. Thirdly, you misuse the term 'gauge' in a way which makes you think you're almost deliberately trying to use it because you know its a physics buzzword but you've no idea its meaning and fourthly, who says all mass quanta have spin? What kind of spin? Where did you learn this?

I don't get it, you know you don't know any quantum field theoory or relativity and you know there's people here who do, yet you try to BS anyway, either by trying to tell us our work, which you don't know or understand or by simply making stuff up. Why? Don't you realise your lies don't stand up to even the slightest bit of scrutiny?

14. ### VkothiiBannedBanned

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Do fermions have spin, and do quarks?
How do we know, what do we use to determine. measure (gauge) this?

GR uses proper time too, it assumes space and time are relative (I mean, why wouldn't you?). It treats gravity properly because it assumes space and time are treated properly. Newtonian space and time are the units.
Mass looks different at large energy scales. There is a large difference between the result we see with G and Newtonian time as rulers, when we try to fit Maxwell's c into the frame.
In 3+1 spacetime, you can't get rid of gravity, you need relativistic spacetime to be able to scale it as well; unless you can find a solution - one that doesn't halt when you ask it to connect h to Avogadro's scale -> G, the limit for mass, the smallest energy that can escape to c, how this is encoded when it escapes from an infinitely scaled mass, or rather from its horizon.

Rovelli has apparently made a recent advance, he has a consistent result or something for LQG

15. ### AlphaNumericFully ionizedRegistered Senior Member

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All fermions have spin which is half integer, at least according to the spin-statistics theorem. But then not all particles with mass have spin. And not all particles with spin have mass. Examples being the pion and photon respectively. If you want fundamental particles.
*scoff* I mean, like duh! Newton was sooooo stupid for not realising space and time are interlinked into a geometry which wasn't even known to be possible for another 250 years after his death. What a thicky! If only you'd been alive in 1660 so you could point out the obvious fact that space-time is Lorentzian.

*sigh* You just don't bother to stop your lips from flapping, do you?

The presence of G in the relativistic Einstein Field Equations is not a problem, it's REQUIRED. Otherwise, when you took relativity to the Newtonian limit you'd not get the Newtonian limit! Low energy and mass physics IS Newtonian. Therefore any high energy, high mass physics must, when you put in low masses and low energies, look the same as Newtonian physics, because that's how the universe is. One of the crippling features of BS ideas like autodynamics is that its version of Lorentz transforms do not reduce to Galilean transforms for v<<c. Lorentz transforms do.

For instance, the Schwarzchild metric involves G because when you work out the low mass, large distance interaction between two black holes you're effectively doing point mass interactions in Newtonian physics, which we know involves forces $F = G\frac{mm'}{r^{2}}$. If you don't have G in your relativity you don't have G in your Newtonian limit. Relativity corrects the Newtonian errors, so while usiing G in a Newtonian theory isn't going to be perfect, if you added in all the corrects due to interactions between space and time relativity is precisely what you get!

Learn something about effective theories you moron.
Sure you can get rid of gravity, it's called Minkowski space-time. Never heard of special relativity?
That is not the definition of h. Nor does h appear anywhere in classical relativity. Nor does gravity appear in the definition of h. h is fundamentally a quantum mechanical object. G is gravitational. Only when you try to get semi-classical things or beyond (ie full quantum gravity models) do they appear in the same equations. But you wouldn't know that, you've never done it, yet you persist in telling people who have what you assume goes on in those theories.

h has nothing to do with N_a. Planck's derivation of h was to remove the UV catastrophy which plagued classical physics' description of black body radiation. G has nothing to do with N_A because its defined in terms of total mass, not number of particles. [/quote]
Whoopy do. Are you an expert on LQG to or is your divine knowledge limited to just my work?

16. ### VkothiiBannedBanned

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Let me stop you there, you're saying the Newtonian relativity of space and time is self-evident (in fact, you can show this by demonstrating that a spatial switch in 1-dimension is equivalent to a time switch in 1 spatial dimension). You can't say "space and time are irrelative" in Newtons G frame.
Right?
Special relativity is the 'proof' that light has a constant velocity in relative frames; this means if you exchange the space (switch it) for the time, there's this invariant left.
Stop me if you've heard this one.
How did Planck get hold of $E=h\nu\,$ and why doesn't it appear anywhere in classical relativity, I thought the special and general theories were built around it?

17. ### gluonBannedBanned

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Don't nlisten to him Vkothi, he's just out to insult, nothing more and nothing less.

18. ### VkothiiBannedBanned

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Hang on, I think I'm getting this: because Newtonian space and time are relative (3+1), we get G with inertial mass (Avogadro's domain - call it A).
In Minkowski, or M, you got (2,0) -> (3,1) relative spacetime or E. But you got this logic L called Lorentz, you have to encode G(h), and then ct is the alphabet. The messages, are then the frequency/wavelength modulation through the spacetime, or vacuum?

Let me put that in information-speak: The Lorenz is a codec for the ct signals, it transforms distance and time as {G(h),c};
Frequency-shift is discarded by the L-codec, the alphabet is strictly $h\nu$. Fidelity is then determined by background zero-shift in frequency scaling (relative velocity of sender-receiver).
Black-body signals (in A) have a broadband frequency spread (thermal scaling); masses with infinitely scaled G, attenuate relative signals strongly, sending them to an infinite {G(m),ct} horizon in effective zero t.

Last edited: Feb 27, 2009

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Both.

20. ### AlphaNumericFully ionizedRegistered Senior Member

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No, I'm saying that at low velocities and low masses the universe is Newtonian.

No, special relativity is the result of assuming light has the same velocity in all inertial frames.

So infact you don't know any of them otherwise you'd know how they are built up from base assumptions and how they were historically developed. I suggest you read Wikipedia for starters, I'd imagine it has a decent history of the UV catastrophy.

I'm out to expose the sustained lies and BS of idiots. Unfortunately you two leave yourself wide open to that because you both continually lie, attempt to BS knowledge on topics I know and you don't and because neither of you seem to have an capacity for learning from your mistakes you keep doing it.

Whose fault is it if you keep running across a motorway, jumping infront of traffic, when you get hit by a car? If you stayed on the side of the road, I'm not going to swerve the car to hit you.
Seriously, STFU.

21. ### gluonBannedBanned

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I'm out to expose the sustained lies and BS of idiots.

So, your ego allows you to try and bring people down, yet again. Your impressive. Or in other words, your ego only entices your apparent need to proove to people over the internet that you seem to think your a mathematical God.

Ego, yet again. You may as well ask plazma inferno to change your name to Alpha-egotistic. Has a good ring to it, don't you think?

22. ### VkothiiBannedBanned

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That would include, I imagine, the frames at the visible edge of inertial motion?
And why have you deflected a direct question about classical relativity, its connection to GR which you claimed had nothing to do with Planck's BB, which is from massive bodies, so N_A is in there again?

Seriously, keep talkin' dude

23. ### gluonBannedBanned

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Vkothii,

There is no such thing as an '''edge to inertial systems'', by the way. No offense intended, you are one of the more aprreciatively-spoken.