Thunderbolts Forum v3.0

Higgsy wrote: ↑Fri Feb 21, 2020 5:36 pm

EtherQuestions wrote: ↑Fri Feb 21, 2020 5:12 amI wouldn't even call it a prediction. The founders of GR already knew about the precession so they just kept attacking the problem from different angles until they fitted the math into it after-the-known-fact.

Of course one of the things you try to do in theoretical physics is to formulate theories that explain already-known but currently unexplained facts. If Einstein had come up with a theory that just explained the apsidal precession problem by some sort of curve fitting, but which had no other value, then of course your criticism would be valid. But GR is a rather simple conceptual framework (even if the its mathematical formulation is quite complex) which can be expressed very simply in the field equations, which is completely compatible with SR, which reduces in the limit to Newtonian mechanics and which is a consistent theory for gravity. One test of it is whether it correctly explains the Mercury anomaly, which it does.

To be predictive, a scientific theory does not have to foretell the future.
You might as well criticise Maxwell for fitting his mathematics to after-the-known-facts about electricity and magnetism.

Einstein spent 7 years trying to get 40 arcsec or whatever the old number was. Early on he got 18 arcsec, then no better, until i think he finally added mass-energy or some such rubbish, & got the desired 40.

crawler wrote: ↑Sun Feb 23, 2020 9:29 pm Einstein spent 7 years trying to get 40 arcsec or whatever the old number was. Early on he got 18 arcsec, then no better, until i think he finally added mass-energy or some such rubbish, & got the desired 40.

Don't you feel bad about misrepresenting the development of the theory of general relativity?

Higgsy wrote: ↑Mon Feb 24, 2020 1:05 am

crawler wrote: ↑Sun Feb 23, 2020 9:29 pm Einstein spent 7 years trying to get 40 arcsec or whatever the old number was. Early on he got 18 arcsec, then no better, until i think he finally added mass-energy or some such rubbish, & got the desired 40.

Don't you feel bad about misrepresenting the development of the theory of general relativity?

I cant find the article today. Anyhow the best number that we now have is 46 arcsec.

And the Einsteinian mafia have been up to their old tricks again. http://www.alternativephysics.org/book/ ... helion.htm

Using HORIZONS Data
There is another source of data we can use to get starting positions and velocities for all the planets and the Sun: JPL’s HORIZONS system [6]. It can give us the position and velocity of all the planets the Sun for a requested date and time, relative to the Solar System Barycentre.

The starting time will be chosen as February 1st 2001 at 15:14, because this corresponds to a perihelion point of Mercury. With these starting conditions, running a simulation over a hundred year period gives this result:
(click to enlarge)
The slope on this is 531.7 arcs/century. This is now almost identical to the ‘official’ amount of 531.63 arcs/century.

What has happened? Why does this not agree with the above simulation showing 528.2 arcs?

A casual look at the end positions of the planets shows Earth to be in a very different location than where it started – 22 degrees further ahead. After 100 years, or any integer multiple number of years, Earth should be at the same place as where it started.

Looking at the other planets and comparing their simulated location to where HORIZONS says they should be located 100 years later (February 2nd 2101 at 15:14), shows they are also far removed from where they should be. How could that be when the simulation accuracy was set so high as to be only out by 10cm?

Further investigation revealed this was because the simulated orbit periods were too short. Earth should have an orbital period of 365.26 days, but the simulation showed 365.03 days. Over a hundred year period Earth thus lost 23 days and ended up 22 degrees further ahead in its orbit.

Similar problems were evident with all the planets – all except Neptune had too short an orbit period. This table reveals the extent of the problem:
Planet.....period(should be)....period (calc).....error %........degree error after 100 yrs
Mercury.....87.97...................87.908............-0.07..............105.4
Venus......224.7...................224.587............-0.05................29.4
Earth.......365.26.................365.031............-0.06................22.6
Mars........686.98.................686.66.............-0.04..................8.9
Jupiter....4332.82...............4329.86.............-0.06..................2.1
Saturn....10755.7...............10747.44.............-0.07..................0.9
Uranus....30687.2...............30668.05............-0.06...................0.3
Neptune..60190.0...............60198.08............+0.01..................-0.03
Table 7: errors in orbital periods from HORIZONS data

The majority of planets have an orbit period around 0.06% less than they should have. For the inner planets this leads them being in completely the wrong location. Mercury is ahead by 105 degrees!

By comparison the simulation used on Fig. 20 was out by 6.3 degrees for Mercury and 0.5 degrees for Earth (over a 100 year period).

Looking further into the cause of this reveals that HORIZONS is giving us the correct positions but wrong velocities of the planets. The velocities are being understated and this results in planets orbiting closer to the Sun with shorter periods.

For example at Mercury’s perihelion, to get a period of 87.97 days, the tangential velocity needs to be 58,987m/s. Instead it is 58,977m/s – 10m/s less – and this results in a period of 87.908 days. For Earth, the velocity at perihelion needs to be 30,292m/s. But HORIZONS (at 2001-01-04 08:53) says it is 30,282m/s, giving a period of 364.90 days.

So the velocities are wrong, and they lead to orbits closer to Mercury and a larger perihelion advance. Given that this advance is almost identical to the amount required by GR, there’s a strong possibility that the velocities have been deliberately tampered with in order to confirm the predictions of GR.

Conclusion
Early analysis of Mercury’s motion was based on simplified models that ignored aspects such as the outer planets’ speeds, their combined contributions, and the motion of the Sun. This led to the conclusion that Newtonian gravity would predict Mercury to precess by 532 arcseconds per century, and that there exists a discrepancy of 43 arcs/cent that can be attributed to General Relativity.

A proper analysis that considers all aspects of Solar System motion however shows the Newtonian prediction to be 528 arcs/cent, making the discrepancy 46 arcs/cent, and this is not in agreement with GR.

crawler wrote: ↑Mon Feb 24, 2020 8:49 am

Higgsy wrote: ↑Mon Feb 24, 2020 1:05 am

crawler wrote: ↑Sun Feb 23, 2020 9:29 pm Einstein spent 7 years trying to get 40 arcsec or whatever the old number was. Early on he got 18 arcsec, then no better, until i think he finally added mass-energy or some such rubbish, & got the desired 40.

Don't you feel bad about misrepresenting the development of the theory of general relativity?

I cant find the article today.

I am not surprised.

Higgsy wrote: ↑Mon Feb 24, 2020 3:10 pm

crawler wrote: ↑Mon Feb 24, 2020 8:49 am

Higgsy wrote: ↑Mon Feb 24, 2020 1:05 am

crawler wrote: ↑Sun Feb 23, 2020 9:29 pmEinstein spent 7 years trying to get 40 arcsec or whatever the old number was. Early on he got 18 arcsec, then no better, until i think he finally added mass-energy or some such rubbish, & got the desired 40.

Don't you feel bad about misrepresenting the development of the theory of general relativity?

I cant find the article today.

I am not surprised.

I cant find that article, but i did find.......
Veisdal – 2019 – Einstein and Hilbert's Race to Generalize Relativity.
https://medium.com/cantors-paradise/ein ... 85f44e3cbe
1914: Einstein publishes the 56-page paper Die formale Grundlage der allgemeinen Relativitätstheorie (“The Formal Foundation of the General Theory of Relativity”) where he recounts and expands on the “Entwurf” (Outline) written a year before with Grossmann. The paper specifies what has been later become known as Einstein’s “scalar theory of gravitation”. Einstein later communicates that he was discontent with the theory, mainly for three reasons:
1. Its restricted covariance doe†s not include uniform rotations;
2. The precession (change in orientation) of the perihelion (closest point of a planet to its star) of Mercury coming out to 18 arcseconds rather than the observed 45 arcseconds per century; and
3. That his proof of the uniqueness of the gravitational Hamiltonian is in fact, incorrect.

crawler wrote: ↑Mon Feb 24, 2020 11:51 pm

Higgsy wrote: ↑Mon Feb 24, 2020 3:10 pm

crawler wrote: ↑Mon Feb 24, 2020 8:49 am

Higgsy wrote: ↑Mon Feb 24, 2020 1:05 am

crawler wrote: ↑Sun Feb 23, 2020 9:29 pmEinstein spent 7 years trying to get 40 arcsec or whatever the old number was. Early on he got 18 arcsec, then no better, until i think he finally added mass-energy or some such rubbish, & got the desired 40.

Don't you feel bad about misrepresenting the development of the theory of general relativity?

I cant find the article today.

I am not surprised.

I cant find that article, but i did find.......
Veisdal – 2019 – Einstein and Hilbert's Race to Generalize Relativity.
https://medium.com/cantors-paradise/ein ... 85f44e3cbe
1914: Einstein publishes the 56-page paper Die formale Grundlage der allgemeinen Relativitätstheorie (“The Formal Foundation of the General Theory of Relativity”) where he recounts and expands on the “Entwurf” (Outline) written a year before with Grossmann. The paper specifies what has been later become known as Einstein’s “scalar theory of gravitation”. Einstein later communicates that he was discontent with the theory, mainly for three reasons:
1. Its restricted covariance doe†s not include uniform rotations;
2. The precession (change in orientation) of the perihelion (closest point of a planet to its star) of Mercury coming out to 18 arcseconds rather than the observed 45 arcseconds per century; and
3. That his proof of the uniqueness of the gravitational Hamiltonian is in fact, incorrect.

Indeed - this illustrates the struggle Einstein had in working towards the final formulation of a theory of gravity, which is not the sort of thing that pops out on the back of a cigarette packet. The Entwurf theory with Grossman, while an enormous step in the right direction, and a remarkable feat, was seen by Einstein and others as inelegant and suffering from several important limitations. This represents the next step, which also had significant limitations, recognised by Einstein. So he did the right thing, and continued to develop the theory, culminating in the Theory of General Relativity, elegant, fully covariant, and matching observations in every respect. It's about as far from curve fitting as a theory can get.

Higgsy wrote: ↑Tue Feb 25, 2020 12:57 amIndeed - this illustrates the struggle Einstein had in working towards the final formulation of a theory of gravity, which is not the sort of thing that pops out on the back of a cigarette packet. The Entwurf theory with Grossman, while an enormous step in the right direction, and a remarkable feat, was seen by Einstein and others as inelegant and suffering from several important limitations. This represents the next step, which also had significant limitations, recognised by Einstein. So he did the right thing, and continued to develop the theory, culminating in the Theory of General Relativity, elegant, fully covariant, and matching observations in every respect. It's about as far from curve fitting as a theory can get.

Mightbeso. But what about the curve fitting by the Horizons team, to make Einstein look good, by putting in false orbital velocity (ie orbit years) for all of the other planets. I think that Horizons reckon that the other planets precess Mercury by 531.63 arcs/cent, & i think that the correct orbit years would bring that to 528.25 arcs/cent (the calc in the link), a diff of 3.4 arcs/cent.

Einsteinians are proud of the accuracy of Einsteinian precession being good to say plus/minus 0.04 arcsec/cent, which when the Horizon's false number is corrected misses the mark by say 3.4 arcs/cent.

It is a miracle that the oldenday's numbers (using very simple ring-planets & a fixed Sun) were so close (especially Clemence) to the modern number (not using ring-planets) of 531.63.

Planet.... Le Verrier.... Newcomb.... Doolittle.... Clemence
Venus....... 276.312...... 277.649..... 276.188 .....277.881
Earth .........90.747 ........91.433 ......90.700 ......90.038
Mars............ 2.471 .........2.485 ........2.472 .......2.536
Jupiter...... 152.900 ......154.004..... 152.904..... 153.584
Saturn .........7.266 ..........7.310 ........7.260....... 7.302
Uranus........ 0.141 ..........0.141........ 0.141 ........0.141
Neptune...... 0.044.......... 0.044........ 0.042 ........0.042
Total........ 529.881 .......533.066 .....529.707 .....531.524 .......Table 2: comparison of researcher’s results
The linked article says that Mathematica says 532.805 (for ring-planets, circular orbits, horizontal plane).


Amount (arcsec/century) ......Cause
531.63 ±0.69 .............Gravitational tugs of the other planets (i think based on proper planets etc).
...0.0254 ..................Oblateness of the Sun
..42.98 ±0.04............. General relativity
574.64 ±0.69 ..............Total
574.10 ±0.65 ..............Observed
Table 1: sources of the precession of perihelion for Mercury

The linked article mentions that the oldenday's ring-planet models (with fixed Sun)(circular orbits)(no speeds of orbits)(no inclinations)(no positioning of planets) were too crude, & that they ended up giving goodish numbers was a miracle.
Using real planets etc in Mathematica gave the following numbers ..........
Using real speeds ......................................... 554.1 arcs/cent
Positioning the planets in combination ............... 593.0
Moving Sun ............................................... 556.0
Elliptical orbits in combination ....................... 540.3
Inclined orbits ........................................... 528.2
Add oblateness .............................................. 0.025
....................................................Total .. 528.25
Which here in the end was 3.4 off the official ...... 531.6

crawler wrote: ↑Tue Feb 25, 2020 4:19 am

Higgsy wrote: ↑Tue Feb 25, 2020 12:57 amIndeed - this illustrates the struggle Einstein had in working towards the final formulation of a theory of gravity, which is not the sort of thing that pops out on the back of a cigarette packet. The Entwurf theory with Grossman, while an enormous step in the right direction, and a remarkable feat, was seen by Einstein and others as inelegant and suffering from several important limitations. This represents the next step, which also had significant limitations, recognised by Einstein. So he did the right thing, and continued to develop the theory, culminating in the Theory of General Relativity, elegant, fully covariant, and matching observations in every respect. It's about as far from curve fitting as a theory can get.

Mightbeso. But what about the curve fitting by the Horizons team, to make Einstein look good, by putting in false orbital velocity (ie orbit years) for all of the other planets. I think that Horizons reckon that the other planets precess Mercury by 531.63 arcs/cent, & i think that the correct orbit years would bring that to 528.25 arcs/cent (the calc in the link), a diff of 3.4 arcs/cent.

I don't believe for a second that one of the most prestigious calculators which astronomers all over the world use for calculating the epherimedes of solar system objects is fudged to the extent of misrepresenting the sidereal year by nearly six hours. It is inconceivable. I am certain that your friend has made an error somewhere in its use. As neither of us have access to his actual query, we won't be able to say precisely where his error is.

Higgsy wrote: ↑Tue Feb 25, 2020 10:40 am

crawler wrote: ↑Tue Feb 25, 2020 4:19 am

Higgsy wrote: ↑Tue Feb 25, 2020 12:57 amIndeed - this illustrates the struggle Einstein had in working towards the final formulation of a theory of gravity, which is not the sort of thing that pops out on the back of a cigarette packet. The Entwurf theory with Grossman, while an enormous step in the right direction, and a remarkable feat, was seen by Einstein and others as inelegant and suffering from several important limitations. This represents the next step, which also had significant limitations, recognised by Einstein. So he did the right thing, and continued to develop the theory, culminating in the Theory of General Relativity, elegant, fully covariant, and matching observations in every respect. It's about as far from curve fitting as a theory can get.

Mightbeso. But what about the curve fitting by the Horizons team, to make Einstein look good, by putting in false orbital velocity (ie orbit years) for all of the other planets. I think that Horizons reckon that the other planets precess Mercury by 531.63 arcs/cent, & i think that the correct orbit years would bring that to 528.25 arcs/cent (the calc in the link), a diff of 3.4 arcs/cent.

I don't believe for a second that one of the most prestigious calculators which astronomers all over the world use for calculating the epherimedes of solar system objects is fudged to the extent of misrepresenting the sidereal year by nearly six hours. It is inconceivable. I am certain that your friend has made an error somewhere in its use. As neither of us have access to his actual query, we won't be able to say precisely where his error is.

This seems a bit too much indeed.
On the other hand, I've been using Horizons myself quite a bit, and I might say that its precision sometimes leaves much to be desired. In some cases the problem is obviously caused by certain numerical procedures (e.g. for nearly circular orbits - such as Neptune's - true anomaly sometimes starts to decrease over time: simply because the argument of perihelion is recalculated every time, which results in discrepancies due to low eccentricity), while in others some other technical factors may come into play (the use of osculating elements etc.), which leads to constant erratic changes of orbital parameters (the amplitude of change is quite small, but much larger than their assumed precision - e.g. often you'll see changes already in the fourth significant digit over a span of days). Plus, there is uncertainty in Earth's orientation data (which is recalibrated every couple of weeks), so they usually state that their predictions are valid only a few months ahead (if we're talking about high accuracy).

paladin17 wrote: ↑Tue Feb 25, 2020 12:26 pm

Higgsy wrote: ↑Tue Feb 25, 2020 10:40 am I don't believe for a second that one of the most prestigious calculators which astronomers all over the world use for calculating the epherimedes of solar system objects is fudged to the extent of misrepresenting the sidereal year by nearly six hours. It is inconceivable. I am certain that your friend has made an error somewhere in its use. As neither of us have access to his actual query, we won't be able to say precisely where his error is.

This seems a bit too much indeed.
On the other hand, I've been using Horizons myself quite a bit, and I might say that its precision sometimes leaves much to be desired. In some cases the problem is obviously caused by certain numerical procedures (e.g. for nearly circular orbits - such as Neptune's - true anomaly sometimes starts to decrease over time: simply because the argument of perihelion is recalculated every time, which results in discrepancies due to low eccentricity), while in others some other technical factors may come into play (the use of osculating elements etc.), which leads to constant erratic changes of orbital parameters (the amplitude of change is quite small, but much larger than their assumed precision - e.g. often you'll see changes already in the fourth significant digit over a span of days). Plus, there is uncertainty in Earth's orientation data (which is recalibrated every couple of weeks), so they usually state that their predictions are valid only a few months ahead (if we're talking about high accuracy).

Thanks for that. I haven't used Horizons much myself, so I can't comment on the small imprecisions you find. But I think we agree the error of hours in a year claimed above is highly unlikely.