Why is there so much crackpot physics?

[Dinwar]

Anyway: Yes, if you actually use the law of gravity (the actual equation, not your guesswork version of it) you find that gravity IS strong enough to move stars around. Alpha centauri and the Sun, for example? Yes, they exert very small acceleration on one another. This acceleration is so small, it would take 140,000,000 years for Alpha Centauri to orbit the Sun once. But you know what? That's pretty fast by astronomical standards. The Milky Way has been here for 14,000,000,000 years. Ditto for the Sun's orbit around the Milky Way---the Milky Way's gravity exerts a *smallish* force on the Sun, but that force is enough to make the Sun orbit with about the right period.

And now I'm looking at my geologic map, trying to figure out how many orbits there would have been during the Phanerozoic.

This orbit started in the Early Cretaceous (Valanginian), the one before started in the Permian (Artinskian), and the one before that started in the Silurian (Ludfordian/Pridolian). The one before that started in teh Ediacaran.

Just thought I'd share that bit of trivia with you. I'm gonna go back to lurking now.

 

[ben m]

And now I'm looking at my geologic map, trying to figure out how many orbits there would have been during the Phanerozoic.

This orbit started in the Early Cretaceous (Valanginian), the one before started in the Permian (Artinskian), and the one before that started in the Silurian (Ludfordian/Pridolian). The one before that started in teh Ediacaran.

Just thought I'd share that bit of trivia with you. I'm gonna go back to lurking now.

Oh, hey, but Alpha Centauri is probably *not actually* in a circular orbit around the Sun. Ignoring the influence of other stars, Alpha Centauri is probably in a hyperbolic orbit, i.e. an unbound orbit, past the Sun; i.e., given its current position and velocity, it happens to be starting off above the Sun's escape velocity. (I don't know specifically, but the escape velocity from an r=4 ly orbit is very small, and *most* stars would be expected to have velocities much higher than this.)

In any case, the Oort cloud (distance ~ 1 ly) is about as far as you can get such that the Sun's gravitational influence dominates the influence of all random passing stars. Even if AC happened to be, right now, at the velocity/position from which it would continue in a 170My orbit, it'd certainly get perturbed out of that orbit before completing it.

 

[Dinwar]

Oh, I know that--I'm not saying that DID happen. I was just putting the numbers into a context that I'm more familiar with. 140,000,000 years isn't, in geology, a terribly long time. In paleontology it's more substantial, but not overly so. The only conclusion to draw from my statement is that a lot happens in 140 million years.

 

[dasmiller]

Oh, hey, but Alpha Centauri is probably *not actually* in a circular orbit around the Sun.

Especially bearning in mind that the Alpa Centauri system has about double the mass of our solar system. If there were an actual orbit involved (and for the reasons you discussed, there isn't), it would be closer to say that Sol is in orbit about Alpha Centauri. And, of course, it would be most accurate to say that the two systems were revolving around a common center of mass which is about 1.4 LY from here.

Ignoring the influence of other stars, Alpha Centauri is probably in a hyperbolic orbit, i.e. an unbound orbit, past the Sun; i.e., given its current position and velocity, it happens to be starting off above the Sun's escape velocity. (I don't know specifically, but the escape velocity from an r=4 ly orbit is very small, and *most* stars would be expected to have velocities much higher than this.)

The back of my envelope says that AC's escape velocity (from Sol) would be about 81 meters/sec or 0.08 km/s, and that's pretty slow. Wikipedia reports that AC has radial velocity of 21.6 km/s; I haven't checked the proper motion but that radial term alone is 265X escape velocity.

Of course, the sun's escape velocity from Alpha Centauri would be about 1.4x that (~115 m/s), but that's still less than 1% of the radial velocity.

In any case, the Oort cloud (distance ~ 1 ly) is about as far as you can get such that the Sun's gravitational influence dominates the influence of all random passing stars. Even if AC happened to be, right now, at the velocity/position from which it would continue in a 170My orbit, it'd certainly get perturbed out of that orbit before completing it.

 

[catsmate]

Gravity may be the weakest force but it's the only one that both acts on every kind of particle and acts over potentially infinite distances.

This. Nuclear and EM forces effect only certain particles while gravity effects everything. A minor detail icebear seems to want to gloss over. Of course he's also off by a bit about the strength of gravitational attraction....

 

[fuelair]

As to the OP, it is because there are still so many crackpots. Not to mention their camp-followers: the inept, the incompetent, the ignorant and the willfully ignorant, incompetent and inept.

 

[ben m]

Oh, I know that--I'm not saying that DID happen. I was just putting the numbers into a context that I'm more familiar with. 140,000,000 years isn't, in geology, a terribly long time. In paleontology it's more substantial, but not overly so. The only conclusion to draw from my statement is that a lot happens in 140 million years.

Y'know, in most cases, when I read about geology I'm frequently surprised by how short the timescales are. I think what my brain does is take the age of the Earth (4000 My) and divide it by the area, and assume that when I look around the surface I should see an even mix of 3000-My and 2000-My and 1000-My old features. Maybe biased a *little* towards recent times.

But then I look at actual familiar features and they're all incredible novelties---5 My old mountain ranges (the last 0.1% of the age of the Earth), 50 My old mountain ranges (the last 1% the age of the Earth) that are considered "old" and are eroded away and buried in sediment; Pangaea was only 300 My ago (the last 8% of the age of the Earth). Things happen *fast* in geology.

 

[Perpetual Student]

As to the OP, it is because there are still so many crackpots. Not to mention their camp-followers: the inept, the incompetent, the ignorant and the willfully ignorant, incompetent and inept.

That's not a satisfactory answer, in my opinion. We are all ignorant, inept and incompetent with respect to some endeavor not within the scope of our own experience and expertise. But most of us do not make up stuff and pretend we do have such knowledge and competence; instead we respect the people who have spent their lives mastering some subject not within our own area of experience -- and -- we form our own opinions with their assistance.

 

[jaydeehess]

That's not a satisfactory answer, in my opinion. We are all ignorant, inept and incompetent with respect to some endeavor not within the scope of our own experience and expertise. But most of us do not make up stuff and pretend we do have such knowledge and competence; instead we respect the people who have spent their lives mastering some subject not within our own area of experience -- and -- we form our own opinions with their assistance.

One word.
Ego

Most people have it under control. Some do not. Those who do not consider themselves expert at anything that touches their fancy.

 

[sol invictus]

The usual claim is 95%.

No, it is not.

Claiming 25% would be much worse, i.e. it would make the person making the claim look much dopier.

What is "dopy" is making false statements with great confidence.

Again gravity is by 40 orders of magnitude th eweaket force in nature. Asking gravity to hold galaxies together is like wanting the littlest kid in the school to compete in the power-lifting event.

As above.

 

[lpetrich]

I decided to look at the modeling of the Earth and the Sun more closely.

For the Earth, one has a lot of data to work with: rotation rate, precession rate, size, flattening, gravity details, and seismic-wave velocities for its entire interior.

Its internal composition one has to guess from the compositions of meteorites, because only the outer few mi/km are directly accessible. This is because most meteorites are relatively unprocessed material from the Solar System's formation, thus having relatively little fractionation. The Earth's crust is well-known for being very fractionated, and is thus not very usable.

But one seems to do OK in working out the Earth's structure, not only for its mantle, but also for its core:
An equation of state for liquid iron and implications for the Earth's core - Anderson - 2012 - Journal of Geophysical Research: Solid Earth (1978–2012) - Wiley Online Library

Let's see how estimates for the Earth's interior depend on the gravitational constant. Its overall measured mass depends on G, of course: one measures G * it. Likewise for the anisotropic parts of its gravitational field. The second-order part gives moment-of-inertia differences, all multiplied by G. With precession, one gets moments of inertia multiplied by G.

To find its structure, one has to solve a system of differential equations:
dM/dr = 4*pi*den*r²dP/dr = - G*M*den/r²dP/d(den) = v²
The second and third ones yield:
d(den)/dr = - G*M*den/(r²*v²)
Factoring out the gravitational constant yields:
d(G*M)/dr = 4*pi*(G*den)*r²d(G*den)/dr = - (G*M)*(G*den)/(r²*v²)

So one gets from seismic velocities and the Earth's gravity G*den, G*M, and G*P over its interior.

Since the densities and compressions are pretty much what one expects from the Earth's extrapolated interior compositions, one concludes that G for the Earth's size is close to G for lab sizes.

 

[lpetrich]

Turning to the Sun, one has its size, G*mass, photon and neutrino luminosities, and seismic waves (helioseismology^WP). Here again, we get good success in modeling the Sun's interior:

The age of the Sun and the relativistic corrections in the EOS | A&A, [astro-ph/0204331] The age of the Sun and the relativistic corrections in the EOS

So like G(Earth's size), G(Sun's size) must be close to G(lab-experiment size).

Turning to the Solar System, there is not much evidence of gravity discrepancies, either in the motions of the planets and their satellites, or in the motions of spacecraft. JPL Solar System Dynamics has high-precision ephemerides (tables of positions) for the more massive Solar-System objects.

So G(Neptune's orbit) must be close to G(lab-experiment size).

Looking outside the Solar System, one can do asteroseismology^WP on stars, just like helioseismology. In fact, planet-search efforts often do a lot of asteroseismology. The variations of Cepheid variables and the like also offer opportunities for asteroseismology. One finds that gravity behaves pretty much as in our Solar System. One also finds that from observing binary and multiple stars, especially those with very eccentric orbits.


For star clusters and galaxies, one can analyze them as gases of stars and dark-matter particles, and one can do N-body simulations, but I haven't found much on how well these theoretical models fit observations. But I don't see much that indicates that our conception of gravity will have to be revised, other than MOND as an alternative to dark matter.

 

[tsig]

That's not a satisfactory answer, in my opinion. We are all ignorant, inept and incompetent with respect to some endeavor not within the scope of our own experience and expertise. But most of us do not make up stuff and pretend we do have such knowledge and competence; instead we respect the people who have spent their lives mastering some subject not within our own area of experience -- and -- we form our own opinions with their assistance.

Some want the title of master without doing the work, they are like those who wear medals they've never earned, they mistake the appearance for reality and think if they can look and talk like those they wish to be they will somehow become what they want.

 

[lpetrich]

Some of them put a lot of effort into their crackpottery, it must be said. Like those who find combinations of various constants that yield various quantities like the fine structure constant, the proton-electron mass ratio, etc.

Some of them also seem to believe that they have improved methods, as Farsight does.

 

[Perpetual Student]

Some of them put a lot of effort into their crackpottery, it must be said. Like those who find combinations of various constants that yield various quantities like the fine structure constant, the proton-electron mass ratio, etc.

Some of them also seem to believe that they have improved methods, as Farsight does.

I find Mr. Duffield an interesting and perplexing case. He has clearly dedicated a great deal of his time (perhaps most of his available time?) reading the literature of and about physics/cosmology and he has spent a great deal of time pondering and discussing these subjects. His ability to reference and quote so many historically important papers is quite impressive.
I understand that he has even made the effort to write a self published "vanity" book debunking mainstream physics and maintains some sort of blog.
Yet, he has not made the effort to master the mathematics that would provide him with the missing ingredient for real comprehension -- a fact which has been revealed, for example, through his naïve numerology concerning fundamental constants and through his demonstrated ignorance of QFT.
I find this choice of priorities -- for one who demonstrates a passion for the subject -- very peculiar and difficult to understand.

 

[Reality Check]

Face it: The universe is not expanding.

Fact it, icebear: the overwhelming scientific evidence is that the universe is expanding.
What is the evidence for the Big Bang?

This is what not even Arp has stated or demonstrated. Arp had the invalid idea that some quasars were ejected from ordinary galaxies based on cherry-picked cases as discussed in the Arp objects, QSOs, Statistics thread. The quantized redshift idea turned out to be basically a statistical fluke which vanished with more data.

Galaxies are held together by electromagnetic forces and not gravity. In some cases that's not totally obvious, in others it's very obvious:

http://antwrp.gsfc.nasa.gov/apod/image/9905/ngc6872_vlt.jpg

Wow - way to shoot yourself in the foot, icebear !
That is a picture of a galaxy probably being distorted by the gravity of another galaxy. NGC 6872: A Stretched Spiral

Explanation: What makes NGC 6872 so long? Measuring over 700,000 light years across from top to bottom, NGC 6872 is one of the largest barred spiral galaxies known. The galaxy's elongated shape might have something to do with its continuing collision with the smaller galaxy IC 4970, visible just above center. Of particular interest is NGC 6872's spiral arm on the upper left, as pictured above, which exhibits an unusually high amount of blue star forming regions. The light we see today left these colliding giants before the days of the dinosaurs, about 300 million years ago. NGC 6872 is visible with a small telescope in the constellation of Pavo.

If you knew anything abut gravity or inertia, icebear , then you would know that gravity and inertia can do things like this.

The ignorance in the assertion that galaxies are held together by electromagnetic forces had been addressed by ben m. This is basically the dumb "gravity is 40 orders of magnitude weaker than EM thus everything is EM" stance that we see from plasma cosmology proponents. It is dumb because they ignore that that weakness depends on the situation. The electromagnetic force is zero between massive objects with no charge but the gravitational force is non-zero.

 

[lpetrich]

I find Mr. Duffield an interesting and perplexing case. He has clearly dedicated a great deal of his time (perhaps most of his available time?) reading the literature of and about physics/cosmology and he has spent a great deal of time pondering and discussing these subjects. His ability to reference and quote so many historically important papers is quite impressive.

Like digging up Einstein's Leyden address of 1920.

I understand that he has even made the effort to write a self published "vanity" book debunking mainstream physics and maintains some sort of blog.

His book: Relativity+
He blogs at http://bogpaper.com

Yet, he has not made the effort to master the mathematics that would provide him with the missing ingredient for real comprehension -- a fact which has been revealed, for example, through his naïve numerology concerning fundamental constants and through his demonstrated ignorance of QFT.

He seems to think that he has some better ways of doing physics, even if they are all wrong. Mathematics as non-fundamental is rather obvious.

He also argues much as a theologian argues, by interpreting writings that he considers inspired.

I find this choice of priorities -- for one who demonstrates a passion for the subject -- very peculiar and difficult to understand.

I agree.

 

[BurntSynapse]

What was your question?

You had raised the objection against my advocacy for alternate formulations in physics to resolve anomalies (Q's were offered as a possible reformulation) based on the claim that alternate representations would produce "literally the same thing in different notation". Thus, recommending exploration of alternate formulations is unwarranted.

I agreed with your claim. I pointed out that while true, it missed the point I was advocating in that the calculations we would be likely or able to perform greatly depend on the notation methods we choose, as your examples illustrated

Perhaps a more clear illustration would be: heliocentric calculations produce exactly the same time of sunrise as geocentric, but I think we'd all agree that which model we are using matters for things other than that specific result. With heliocentrism, we tried other calculations and made predictions (unfalsifiable at the time) we would not have obtained from the older model.

History shows we are simply unlikely to try or look for things that seem implausible under older formulations.

My question: Do we agree that if we build decimal-logic computers, or forced people to do computer-related arithmetic in binary, many results we currently consider trivial would not be around for us put in alternate representations?

If so, and if history is any guide, it suggests reconfiguring the categories of a science (via alternate representations) is a key characteristic of revolutionary advance which is generally-accepted as needed in physics.

If there exist transformative advances in any STEM discipline which do not feature such recategorization, I would be interested to learn of them.

Last week, a colleague at NASA forwarded me a new mathematical construct I initially poo-pooed, but on closer review and based on information systems project management criteria, it seems the most promising reformulation in many years: the amplituhedron.

 

[catsmate]

He seems to think that he has some better ways of doing physics, even if they are all wrong. Mathematics as non-fundamental is rather obvious.

He also argues much as a theologian argues, by interpreting writings that he considers inspired.

This. Why strikes me most about Farsight (and that other PM/crank who posts here) is that they seem to think that applying elements of their project management techniques to scientific exploration will reap rewards.

 

[The Man]

You had raised the objection against my advocacy for alternate formulations in physics to resolve anomalies (Q's were offered as a possible reformulation) based on the claim that alternate representations would produce "literally the same thing in different notation". Thus, recommending exploration of alternate formulations is unwarranted.

I agreed with your claim. I pointed out that while true, it missed the point I was advocating in that the calculations we would be likely or able to perform greatly depend on the notation methods we choose, as your examples illustrated

Perhaps a more clear illustration would be: heliocentric calculations produce exactly the same time of sunrise as geocentric, but I think we'd all agree that which model we are using matters for things other than that specific result. With heliocentrism, we tried other calculations and made predictions (unfalsifiable at the time) we would not have obtained from the older model.

History shows we are simply unlikely to try or look for things that seem implausible under older formulations.

My question: Do we agree that if we build decimal-logic computers, or forced people to do computer-related arithmetic in binary, many results we currently consider trivial would not be around for us put in alternate representations?

If so, and if history is any guide, it suggests reconfiguring the categories of a science (via alternate representations) is a key characteristic of revolutionary advance which is generally-accepted as needed in physics.

If there exist transformative advances in any STEM discipline which do not feature such recategorization, I would be interested to learn of them.

Last week, a colleague at NASA forwarded me a new mathematical construct I initially poo-pooed, but on closer review and based on information systems project management criteria, it seems the most promising reformulation in many years: the amplituhedron.

Once again you seem to present yourself in a self-contradictory fashion. At first asserting “History shows we are simply unlikely to try or look for things that seem implausible under older formulations. “ and then later “If so, and if history is any guide, it suggests reconfiguring the categories of a science (via alternate representations) is a key characteristic of revolutionary advance which is generally-accepted as needed in physics.”. It is precisely looking for things “that seem implausible under older formulations.” that drive “reconfiguring the categories of a science (via alternate representations)”. The amplituhedron being a good example (removing the precepts of locality and unitarity) and I can tell you its acceptance won’t be “based on information systems project management criteria” but on how well the model reflects and predicts observational results.

As ben m has noted, you assert “if history is any guide…” and the amplituhedron further exemplifies this is already how modern science works. What exactly are you looking for that science isn’t currently doing and hasn’t (which would be contrary to your own assertion) generally historically done?

Amplituhedron thread.
http://www.internationalskeptics.com/forums/showthread.php?postid=9504960#post9504960