Gravitational constant appears universally constant, pulsar study suggests

August 6, 2015, National Radio Astronomy Observatory
A 21-year study of a pair of ancient stars -- one a pulsar and the other a white dwarf -- helps astronomers understand how gravity works across the cosmos. The study was conducted with the NSF's Green Bank Telescope and the Arecibo Observatory. Credit: B. Saxton (NRAO/AUI/NSF)

Gravity, one of the four fundamental forces of nature, appears reassuringly constant across the Universe, according to a decades-long study of a distant pulsar. This research helps to answer a long-standing question in cosmology: Is the force of gravity the same everywhere and at all times? The answer, so far, appears to be yes.

Astronomers using the National Science Foundation's (NSF) Green Bank Telescope (GBT) in West Virginia and its Arecibo Observatory in Puerto Rico conducted a 21-year study to precisely measure the steady "tick-tick-tick" of a pulsar known as PSR J1713+0747. This painstaking research produced the best constraint ever of the gravitational constant measured outside of our Solar System.

Pulsars are the rapidly spinning, superdense remains of massive stars that detonated as supernovas. They are detected from Earth by the beams of radio waves that emanate from their magnetic poles and sweep across space as the pulsar rotates. Since they are phenomenally dense and massive, yet comparatively small – a mere 20–25 kilometers across – some pulsars are able to maintain their rate of spin with a consistency that rivals the best atomic clocks on Earth. This makes pulsars exceptional cosmic laboratories to study the fundamental nature of space, time, and gravity.

This particular pulsar is approximately 3,750 light-years from Earth. It orbits a companion white dwarf star and is one of the brightest, most stable pulsars known. Previous studies show that it takes about 68 days for the pulsar to orbit its white dwarf companion, meaning they share an uncommonly wide orbit. This separation is essential for the study of gravity because the effect of gravitational radiation – the steady conversion of orbital velocity to gravitational waves as predicted by Einstein – is incredibly small and would have negligible impact on the orbit of the pulsar. A more pronounced orbital change would confound the accuracy of the pulsar timing experiment.

"The uncanny consistency of this stellar remnant offers intriguing evidence that the fundamental force of gravity – the big 'G' of physics – remains rock-solid throughout space," said Weiwei Zhu, an astronomer formerly with the University of British Columbia in Canada and lead author on a study accepted for publication in the Astrophysical Journal. "This is an observation that has important implications in cosmology and some of the fundamental forces of physics."

"Gravity is the force that binds stars, planets, and galaxies together," said Scott Ransom, a co-author and astronomer with the National Radio Astronomy Observatory in Charlottesville, Va. "Though it appears on Earth to be constant and universal, there are some theories in cosmology that suggest gravity may change over time or may be different in different corners of the Universe."

The data taken throughout this experiment are consistent with an unchanging gravitational constant in a distant star system. Earlier related research in our own Solar System, which was based on precise laser ranging studies of the Earth-Moon distance, found the same consistency over time.

"These results – new and old – allow us to rule out with good confidence that there could be 'special' times or locations with different gravitational behavior," added Ingrid Stairs, a co-author from the University of British Columbia in Canada. "Theories of gravity that are different from general relativity often make such predictions, and we have put new restrictions on the parameters that describe these theories."

Zhu concluded: "The gravitational constant is a fundamental constant of physics, so it is important to test this basic assumption using objects at different places, times, and gravitational conditions. The fact that we see gravity perform the same in our Solar System as it does in a distant star system helps to confirm that the gravitational constant truly is universal."

Explore further: Astronomers use vanishing neutron star to measure space-time warp

More information: "Testing Theories of Gravitation Using 21-Year Timing of Pulsar Binary J1713+0747," W.W. Zhu et al. arxiv.org/abs/1504.00662

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rossim22
2.5 / 5 (19) Aug 06, 2015
So, this study has somehow "confirmed" that the "force of gravity is the same everywhere and at all times" yet another phys.org article published less than four months ago showed that the constant oscillates like a sine wave. All this confirmational bias is incredibly obvious. If an observation does not fit the model, it is ignored or new physics is invented to cope with the changes... all while never attempting to question the underlying gravitational dogma.
PhysicsMatter
3.1 / 5 (15) Aug 06, 2015
And that's the issue of confusing methodology. They claim that they've proven constancy of G but that's not what they actually did.

What they've proven is that in many LOCAL settings in some small part of universe when solving a two body problem (big approximation right here) with small to moderate separation between two bodies, calculated orbital periods (via methods of theory spectral analysis of EM waves) would yield (as a calculated value) gravitational constant that differs negligibly when analyzing different epochs or distances from earth.

That's not the proof of constancy and/or universality of G throughout the Universe.
What was proven was that certain approximations used in gravity theory work locally?

PhysicsMatter
1.2 / 5 (10) Aug 06, 2015
To truly address the issue many-body problem should be solved, trajectories of every material body in the universe i.e. every elementary particle trajectory determined and then run multidimensional least square fit to find G that would be truly universal to the well determined accuracy tending to infinity, error to zero for whole universe. Task impossible to accomplish due to many reasons including electromagnetic fields that would have to be taken into consideration i.e. need for unified theory of Gravity and EM which does not exist yet.
arom
Aug 06, 2015
This comment has been removed by a moderator.
Kedas
3.7 / 5 (6) Aug 07, 2015
Let me try to get a 5/5 score here:

We don't know (yet)!
Ultron
not rated yet Aug 07, 2015
So, this study has somehow "confirmed" that the "force of gravity is the same everywhere and at all times" yet another phys.org article published less than four months ago showed that the constant oscillates like a sine wave. All this confirmational bias is incredibly obvious. If an observation does not fit the model, it is ignored or new physics is invented to cope with the changes... all while never attempting to question the underlying gravitational dogma.


Both can be true if there is some unknown gravitational influence during measurements of Gravity constant on Earth.
Benni
1.9 / 5 (13) Aug 07, 2015
And that's the issue of confusing methodology. They claim that they've proven constancy of G but that's not what they actually did.

What they've proven is that in many LOCAL settings in some small part of universe when solving a two body problem (big approximation right here) with small to moderate separation between two bodies, calculated orbital periods (via methods of theory spectral analysis of EM waves) would yield (as a calculated value) gravitational constant that differs negligibly when analyzing different epochs or distances from earth.

That's not the proof of constancy and/or universality of G throughout the Universe.
What was proven was that certain approximations used in gravity theory work locally?


You could almost substitute DM for G in your post. Locate a local gravitational anomaly & create outlandish hypotheses claiming it proves 75-90% of the universe is missing.
HannesAlfven
1 / 5 (8) Aug 07, 2015
The study foremost assumes that the flicker of a pulsar is necessarily the result of a spin -- rather than a luminous electrical discharge.

The idea of a constant G was never authentically in question, because the assumptions were never actually fully questioned. And yet, we are led with this assumption to believe that PSR J1748-2446ad, the fastest-spinning pulsar known, rotates at 716 times per second.

A nucleus or charge free atom made up of only neutrons has never been synthesized in any laboratory. Lone neutrons decay into proton/electron pairs in less than 14 minutes; atom-like collections of two or more neutrons will fly apart almost instantaneously.

Why would the theorists refuse to question this assumption?
shavera
4.3 / 5 (16) Aug 07, 2015
Way to only tell half the story, Benni. In science, we do something after speculating wildly. We test our hypotheses. I know it may be hard to hear as a crank, that we don't just make an argument based on how the universe "should be" because some ancient philosopher said so, or because one engineer from the 60s said so, or because... you say so.

Hypothesis: Maybe we don't know all of the types of matter in the universe. (pretty reasonable hypothesis, really) If we don't know all the types of matter, maybe there's another kind of "stuff" out there that has mass that we just haven't measured yet.

Test: Well the hypothesis has its origins in galactic rotation curves, so let's toss those out for the moment, since we form the hypothesis to fit that observation. The hypothesis suggests if we "measure" the mass of a galaxy based on how much light it emits (with obvious error bars around such a measurement), we should see gravitational lensing that's stronger than just that mass alone
shavera
4.3 / 5 (16) Aug 07, 2015
cont.
Guess what? We saw that. Galaxies bend light more strongly than their visible mass alone would suggest.

Test: If two galactic clusters collide, and this stuff we don't know about is being carried gravitationally with the galaxies, we should see that, since this stuff we don't know doesn't interact with matter as much, it won't slow down like the gasses within the clusters.

Guess What? That's what we observe. We observe that the mass is being carried with the galactic clusters, even though they leave a wake of colliding gasses behind.

Test: If this stuff we don't know has always been around, it should affect how sound waves traveled in the early plasma universe (ie when our universe was all a plasma and not mostly neutral atoms like it is now).

Guess What? When we measure those early soundwaves, we see that the stuff we know about is insufficient to explain what we see. But if you include stuff we don't know about, then it matches quite well
shavera
4.3 / 5 (17) Aug 07, 2015
So I'm left wondering why the crank community is so bloody upset at the idea of dark matter. Dark matter is LITERALLY scientists admitting they don't know everything.

Of course, the cranks are gonna crank about how, well of course science doesn't know everything, only their personal cranky view of the universe explains it all.

It really is a "have your cake and eat it too" scenario. We're accused of asserting we know things we don't and being inflexible about thinking about new ideas. But we're at the same time accused of not explaining everything in the universe *right now* so we must obviously be lying about what we think we know.

Science takes time. Physics isn't done learning about our universe. In our lifetime, there will still be unanswered questions.

And that sucks if you want one explanation to explain everything. You almost certainly won't get it, at least from science. But I don't see how inventing your own mythology and presenting it as fact is any better
HannesAlfven
1 / 5 (8) Aug 07, 2015
Re: "Hypothesis: Maybe we don't know all of the types of matter in the universe. (pretty reasonable hypothesis, really) If we don't know all the types of matter, maybe there's another kind of "stuff" out there that has mass that we just haven't measured yet."

Of course it is, and let's be clear that people have taken a very serious look at the idea by this point.

What has NOT been fully considered to-date is that the cosmic plasma models might be wrong, as Nobel laureate Alfven -- the inventor -- suggested in his Nobel speech in 1970 (and many times before).

And what has not been adequately explained, to date, by anybody, is why the cosmic plasma models are somehow immune to questioning.

Instead, where filaments are observed to be lit up and connected to this "cosmic web", we are invited to consider that there is a flashlight somewhere lighting those filaments up.
shavera
4.3 / 5 (10) Aug 07, 2015
And what has not been adequately explained, to date, by anybody, is why the cosmic plasma models are somehow immune to questioning


Actually, I'm always left wondering why cranks think we haven't questioned it. Scientists like proving each other wrong most of all. No one remembers the person who confirmed something we already thought was correct. We remember the person who overturns what we think we know.

Astronomers do consider the plasmas in the universe. They do consider the magnetic fields. They look for observables that don't agree with their predictions.

If the EU/PC has some actual observable prediction to make, what is it? What measurable can we do that definitively shows PC, but not the standard cosmology? Even if it hasn't been made, what should we look for? What quantitative (not qualitative) measure can we perform to definitively show PC over standard cosmology? If we do it, and it's a null result would you stop pushing for PC?
shavera
4.5 / 5 (12) Aug 07, 2015
Let me give a famous "for example."

Gravity makes everything accelerate at a constant rate, regardless of the accelerated object's mass ( in the case that the smaller object is overwhelmingly smaller), right? So, let's pretend that light, even though it's massless, is somehow magically accelerated by gravity. What we would expect to see is that a star slightly behind our sun appears out of place by some small number of degrees.

OTOH, GR predicts that it will deflect, but by a factor of 2, IIRC, greater than the naive assumption of constant acceleration.

So, the measurable you can say is: "If you observe the deflection of starlight near the limb of our sun, it should be x degrees and not y degrees." Then, when we did that, and found x and not y, that was a measurable that supported the theory.

Many many many more such measurables were produced, tested, and support GR very very well (over conventional Newtonian physics). What can we do to "prove" PC?
carlo_piantini
2 / 5 (4) Aug 07, 2015
Hey shavera,
We've had pretty gentle conversations before, so I hope we can continue.

What can we do to "prove" PC?

Well, the first thing that we can do is to get into a lab, and attempt to replicate the morphology/magnetic structures/rotation curves that we see in space plasmas in the lab. Bostick was able to do a decent job at simple replications (at least from what I understand), and Peratt was able to do it with computer simulations (although his models produce the issue of the "missing synchrotron radiation" problem). Can we do better than this? I think we can, and I think we should. I distinctly prefer this inductive method of model building - it worked for Birkeland, it worked very well for Alfven, and I think it can continue to work for the rest of the community. If we can produce, in a real-world laboratory, the same structures that we see in space, then I think this would take as an extremely long way towards understanding how they form in space.

cont.
carlo_piantini
2 / 5 (4) Aug 07, 2015
The second thing that needs to be done - which is the thesis I will be working on for several years - is to take Alfven's criticisms of our current cosmic plasma models (mentioned, for example, in his Nobel prize notes), and do two things with them: (a) see if the principles he espouses genuinely apply to laboratory plasma physics, and (b) study the primary astrophysical literature to *see* if the criticism holds water - the misapplication of MHD and the "frozen-in" theorem, ignoring plasma's tendency towards inhomogeneity and charge separation, not applying elements like double-layers or homopolar generators to our models, currents forming filaments - are these criticisms valid? Again, no one is arguing that astrophysicist don't *consider* magnetism or plasma (although I would certainly argue that they do not consider electric currents anywhere near as much as they should), but simply are too heavily theoretical, based on assumed *ideal* conditions.

cont.
carlo_piantini
2 / 5 (4) Aug 07, 2015
Finally, I think what should be done is to take the new evidence we've discovered, say, in the last ~2 years alone - helically shaped magnetic fields wrapped around spiral arms, plasma flowing inward towards the galactic core within these fields (which, logically, should definitely produce electric currents and charge separation via double layers), the inflow of plasma from ISM filaments into protogalaxies (most likely along similar helical B fields), the ubiquitous filamentation of galaxy plasma itself, the propagation of Alfven waves from the galactic center, the helically structured magnetic fields that structure cosmic jets, the measurable electric currents inside those jets (which, most likely, are Birkeland currents) - and (a) acknowledge that these are all elements of Alfven's generalized model, and (b) see if this data can be used to construct a mathematically formalized model of galaxy formation, to *see* if other measurable predictions can be made.

cont.
carlo_piantini
1.8 / 5 (5) Aug 07, 2015
Alfven's ideas were rejected in the ~70s-80s, *well* before the new observations we've made. As I've said before, the majority of his ideas were at first rejected, until new observational evidence confirmed the ideas in principle. So, I believe that it is time to at the very least revisit his ideas of galaxy formation, and see if they hold water. Particularly if they can resolve the issue of dark matter. You've mentioned gravitational lensing as evidence for DM - plasma also produces the same lensing effect through its refractive index. Alfven's model also, supposedly, would resolve the issue of galactic rotation curves. I'm not certain if it could be applicable to the oscillation issue you've mentioned, but, perhaps?

Is any of what I've said unreasonable?
carlo_piantini
2.3 / 5 (3) Aug 07, 2015
Holy shit...mytwocts...did you just agree with me? I'm sorry, that seems snarky, but we just spent all of yesterday debating with each other lol
carlo_piantini
2 / 5 (4) Aug 07, 2015
From the wiki-link posted by mytwocts:

"However, theoretical analysis shows that "many scenarios for the generation of seed magnetic fields, which rely on the survival and sustainability of currents at early times [of the universe are disfavored]",[19] i.e. Birkeland currents of the magnitude needed (1018 amps over scales of megaparsecs) for galaxy formation do not exist." - http://arxiv.org/...31v2.pdf

Again, *if* the arguments against CP galaxy formation are theoretical issues, rather than observational issues - which, historically, was the case with Alfven's work *and Birkeland's* - all the more reason to (a) get in a lab and build an inductive model via replication and (b) review the theoretical application of plasma physics in cosmic plasmas against demonstrated laboratory plasma physics. The arxiv paper discusses a homogenous, neutral cosmic plasma - this is counter to plasma's *demonstrated* tendency towards charge separation and inhomogeneity.
viko_mx
1 / 5 (2) Aug 07, 2015
It is not very sure that gravity is force. And the same physical phenomena stay behind acting gravity on Earth and in diferent regions of cosmic space. I prefer to think of gravity as programmed behavior of structure of local cosmic vacuum which define the local energetic interactions between consituent particals of matter and as a consequence local physical laws.
Benni
1.5 / 5 (8) Aug 07, 2015
Test: Well the hypothesis has its origins in galactic rotation curves, so let's toss those out for the moment, since we form the hypothesis to fit that observation. The hypothesis suggests if we "measure" the mass of a galaxy based on how much light it emits , we should see gravitational lensing that's stronger than just that mass alone.Guess what? We saw that. Galaxies bend light more strongly than their visible mass alone would suggest.


Shavera: Spiral galaxies make up 1/3 of the mass of the Universe. The obvious appearances are that you don't know Rotation Curves are peculiar to Spiral Galaxies & not Ellipticals. The radial arm in which our Sun is located in the MW has an orbital speed of 240 km/s. At the extreme edges of the radial arm the orbital speeds are about 200 km/s. By contrast the orbital speeds of stars at the extreme edges of Ellipticals is 2 km/s & varies by the Inverse Square Law as applied to Newtonian Gravity, redshift verifies this.

cont'd.......
Benni
1.9 / 5 (9) Aug 07, 2015
.....cont'd

Due to the fact that orbital speeds of stars in Ellipticals comport with Newtonian gravity within their mass, it is therefore demonstrable there is no need for those galaxies to have mass envelopes of counter gravity to keep them from flying apart as is the hypothesis for Spirals.

Now that you've learned Spirals compose only 1/3 the mass of the Universe, the remainder must be where? In Ellipticals. The orbital dynamics of Ellipticals don't comport with the Rotation Curves of Spirals, and that's a problem for the DM hypothesis (es) because Ellipticals contain most of the mass of the Universe, up to 70%.

Because 70% of the universe is composed of galaxies that don't require DM glue to keep them together, it became obvious to DM Enthusiasts it must not exist within that fraction of the Universe. Well, that doesn't fit the 75-90% hypothesis does it?

cont'd......
Benni
1.5 / 5 (8) Aug 07, 2015
.....cont'd

Now enter Gravitational Lensing effects within the vicinities of large Ellipticals & the new narrative envisions this as proof that DM also envelopes Ellipticals, or the extreme lensing on the visible edges of their disks, or clusters, could not occur.

In Einstein's GR, he calculated the exact degree of bending of starlight passing the visible disk of the sun. He did the calculation without the need to include gravity effects due to unseen matter. Go ahead, label this old 60's & earlier stuff?
TehDog
4.7 / 5 (13) Aug 07, 2015
@Benni
I don't think this means what you think it does;
"Test: Well the hypothesis has its origins in galactic rotation curves, so let's toss those out for the moment, since we form the hypothesis to fit that observation."

I think that means, "let's ignore them for the purposes of this comment"

"The hypothesis suggests if we "measure" the mass of a galaxy based on how much light it emits"

No type of galaxy is specified, elliptical or spiral.

"we should see gravitational lensing that's stronger than just that mass alone.Guess what? We saw that. Galaxies bend light more strongly than their visible mass alone would suggest."

A result independent of GRC's.

Just what is your objection to the concept of DM? Inquiring minds would like to know :)
docile
Aug 08, 2015
This comment has been removed by a moderator.
docile
Aug 08, 2015
This comment has been removed by a moderator.
Benni
1.4 / 5 (9) Aug 08, 2015
@Benni
I don't think this means what you think it does;
Test: Well the hypothesis has its origins in galactic rotation curves, so let's toss those out for the moment, since we form the hypothesis to fit that observation


......because Elliptical galaxies don't have Rotation Curves & they make up 70% of the mass of the Universe. If 70% of the structures of the Universe do not function with same the Rotational Dynamics of 30% of the mass of the Universe, what laws of gravitational physics would you apply to exempt one type of galactic structure from another?

we should see gravitational lensing that's stronger than just that mass alone.Guess what? We saw that. Galaxies bend light more strongly than their visible mass alone would suggest.
Not true .....you better go take a look at some of those Einstein Rings that occur right at the visible peripheral edges of Ellipticals.

Just what is your objection to the concept of DM?
...you just read it above.
Benni
1.5 / 5 (8) Aug 08, 2015
@TehDog et al,

The structural size of giant Elliptical galaxies are so immense they dwarf even the Andromeda galaxy in breadth.

Within our own Virgo local cluster is an Elliptical 100 times the size of the MW. Can you just imagine the extent of the immensity of the gravity field that creates? Labeled M87 Virgo A., here go read about it: http://messier.se...087.html

If you have never noticed, 99% of the pictures you see of gravitational lensing caused by galactic structures are pictures of galaxies that are Ellipticlas, not Spirals.

When you do see an occasional picture of a Spiral creating an Einstein Ring, the Ring always occurs exactly at the center bulge where the most gravity is, never in the radial arms. So, if there is all this vaunted DM gravity enveloping Spiral galaxies why then do the Einstein Rings occur only at the central bulge of those galaxies? There is no great big mystery why this occurs, it's because that's the greatest concentration of mass.
Benni
1.6 / 5 (7) Aug 08, 2015
Just what is your objection to the concept of DM?
..you just read it above


You can not just disprove the DM hypothesis by hand waving arguments.
That leads to endless discussions going nowhere
You're the one bragging that you are in possession of a "simple caculation" by which the density of DM can be calculated everywhere in the Universe.

Make a solid case
You should do just that, present your "simple calculation"

True, elliptical systems appear to have little DM*, but the dynamics and lensing of galaxy cluster and of spirals do require DM or an alternative explanation
.......An alternate explanation? How about the enormity of the sizes of giant Ellipticals & the Einstein Rings that appear right at the visible periphery? Remember in GR where Einstein calculated gravitational lensing? Probably you don't because you've never read it.

Benni
1.6 / 5 (7) Aug 08, 2015
Gosh gee M87, thanks. You are still hand waving.


"Hand waving" is bragging that you are in possession of a "simple calculation" for the density of Dark Matter & never producing it. Stop "waving" off the production of your vaunted "simple calculation" & produce it so the world can see how far "beyond General Relativity" you are with your grade school level comprehension of science.
docile
Aug 08, 2015
This comment has been removed by a moderator.
Benni
1.7 / 5 (6) Aug 08, 2015
Why we are forced to read about dark matter models in discussion bellow article about stability of gravity constant? Only dumb people of incoherent thinking cannot keep the subject - so that every OT discussion tends to be dumb and distracting too. Just remember:


.......simply because "dumb people" won't explain why NASA launches & lands spacecraft all over our solar system based on the Inverse Square Law of Newtonian Gravity calculations, just as Einstein did in his General Relativity when he put forth the calculations for gravitational lensing as starlight passes the visible disk of the Sun.

So, you want to name call people as being "dumb"? When we see your published peer reviewed paper with the corrected calculations NASA & Einstein neglected, then we can believe the DM Hypotheses has moorings within the proven concepts of General Relativity & not something off the plantations of funny farm science.
docile
Aug 08, 2015
This comment has been removed by a moderator.
Benni
1.4 / 5 (9) Aug 08, 2015
Gosh gee M87, thanks. You are still hand waving.


"Hand waving" is bragging that you are in possession of a "simple calculation" for the density of Dark Matter & never producing it. Stop "waving" off the production of your vaunted "simple calculation" & produce it so the world can see how far "beyond General Relativity" you are with your grade school level comprehension of science.


You are still hand waving and not showing anything close to hard evidence against DM


...........< $0.02 worth, keep "hand waving". You can't follow the Differential Equations in Einstein's GR, so you keep "waving" them off by substituting your grade school comprehension of the most important science in the history of mankind. I think you have a fundamental prejudice problem against Einstein himself,
Benni
1.8 / 5 (5) Aug 08, 2015
"Hand waving" is bragging that you are in possession of a "simple calculation" ...

You see? Now _I_ have to show something
...... after all, you're the one who promised to produce the "simple calculation". When I called you on your bluff to produce the "simple calculation" and you remain recalcitrant to do so, but that is not "hand waiving" on your part.
Benni
1.7 / 5 (6) Aug 08, 2015
I believe you cannot even calculate how much DM would be present within a radius of 1 (Earth) or of 30 a.u. (Neptune) according to the DM hypothesis. Express the result in solar masses. Because if you could, you would not make those silly claims.


Solar Masses of DM in our solar system=0.0 Here's why:

The DM hypothesis is based on the presence of excess gravity within a localized vicinity, for example a Spiral Galaxy. If there were excess gravity within our solar system, Einstein could not have perfectly calculated the gravitational lensing of starlight as it passes the immediate periphery of the Sun's visible disc. If you don't believe this is the case & Einstein made a fundamental error, then you should go to that section of General Relativity, revise it with updated calculations, get them peer reviewed, publish your paper & voila, you become everything you'd ever hoped to be, until then you remain in grade school.

rebelclause
not rated yet Aug 08, 2015
Wasn't there some sort of phase concentration theory the Grail mission was supposed to have proved?
Benni
1.9 / 5 (9) Aug 08, 2015
My question was a different one. WHAT IS ACCORDING TO THE DM HYPOTHESIS THE AMOUNT OF DARK MATTER INSIDE A RADIUS OF 1 ASTRONOMIC UNIT, EXPRESSED IN SOLAR MASSES?
The answer to this question, is a NUMBER. It involves a mul-ti-pli-ca-ti-on.One significant digit is enough. Order of magnitude is also ok. Anything concrete will do.
Please no more silly crank story involving Einstein.


When you stoop to the level of labeling Einstein & his GR as a "crank story", then it's simply time to put you on the "Ignore User". It's so obvious you really have little interest in the highest levels of science since the dawn of the history of mankind. You have a hate complex that pervades your entire mindset & fabric of your being. Those of us whose life's endeavors are in the field of science abhor your manner of behavior & find your prejudice despicable.

Returners
1 / 5 (3) Aug 08, 2015
I'm wondering how they solved the problem of not knowing how much of the magical "Dark Matter" entity is involved in this system, since that would greatly effect the "apparent" measure of G.
EWH
1 / 5 (2) Aug 09, 2015
I'm suspicious that the apparent stability of G (rather than a variation of a few ppm to 1ppt around a baseline) is an artifact of defining the speed of light to be a constant. The unit of G is : m^3 s^-2 kg^-1. Assuming constant c and c^2, negligible variation in pulsar radius and mass, then G mass/(c^2 radius) has dimensionless units.

In other words, if the radius and mass of the pulsar are fixed, then G cannot change independently of the speed of light. Since the speed of light is fixed by definition, then in he case of a pulsar, G is fixed by definition. This also makes intuitive sense because changes in G should create changes in the gravitational field, which will affect the degree of gravitational lensing, which is to say the refractive index of the space near the pulsar, which is to the same as saying the the local speed of light is fractionally slower than in field-free space.
docile
Aug 09, 2015
This comment has been removed by a moderator.
AGreatWhopper
2 / 5 (4) Aug 09, 2015

When you stoop to the level of labeling Einstein & his GR as a "crank story", then it's simply time to put you on the "Ignore User". It's so obvious you really have little interest in the highest levels of science since the dawn of the history of mankind. You have a hate complex that pervades your entire mindset & fabric of your being. Those of us whose life's endeavors are in the field of science abhor your manner of behavior & find your prejudice despicable.


With this reaction Benni has crossed the line to pathological misinformation.
The tendency is present in all his posts but is now manifest.
The sanctimonious "Those of us who ..." of course refers to his crackpot sock puppets.


Benni is the sock puppet, returners is the one with his hand up their arse.

The name "returners" was what he adopted after running 1/2 a dozen then leaving in a hissy fit. Fucking drama queen. When he came back he was "returners". I have the IP logs to prove it.
jonesdave
2.7 / 5 (7) Aug 09, 2015
So, this study has somehow "confirmed" that the "force of gravity is the same everywhere and at all times" yet another phys.org article published less than four months ago showed that the constant oscillates like a sine wave. All this confirmational bias is incredibly obvious. If an observation does not fit the model, it is ignored or new physics is invented to cope with the changes... all while never attempting to question the underlying gravitational dogma.


Here's an idea: jump out of a 3rd floor window. Report back. How variable was it for you?
jonesdave
3.4 / 5 (10) Aug 09, 2015
@Rossim22
"So, this study has somehow "confirmed" that the "force of gravity is the same everywhere and at all times" yet another phys.org article published less than four months ago showed that the constant oscillates like a sine wave. All this confirmational bias is incredibly obvious. If an observation does not fit the model, it is ignored or new physics is invented to cope with the changes... all while never attempting to question the underlying gravitational dogma."

So come on, bright spark, where is your alternative? Where can I download it?
Or, as usual, are you talking absolute sh*te?
How's the electric comet b*llocks going? Not good, is it?
jonesdave
3.7 / 5 (9) Aug 09, 2015
Place is full of fu*kw*ts. Seriously. Come on Rossim, given that every other electric universe nutter seems to have legged it: where is your evidence? For anything?
Save you looking, there isn't any. Belief in Thornhill's garbage requires one thing, and one thing only; scientific illiteracy, and a very limited IQ.
jonesdave
3.5 / 5 (8) Aug 09, 2015
Come to think of it, that's two things: however, you get my drift.
I could have added a massive amount of gullibility. And so it goes.
jonesdave
3.5 / 5 (8) Aug 09, 2015
Still, as long as Wal's making a living, eh?
jonesdave
3.5 / 5 (8) Aug 09, 2015
Saps.
yep
2 / 5 (4) Aug 10, 2015
Place is full of fu*kw*ts. Seriously. Come on Rossim, given that every other electric universe nutter seems to have legged it: where is your evidence? For anything?
Save you looking, there isn't any. Belief in Thornhill's garbage requires one thing, and one thing only; scientific illiteracy, and a very limited IQ.


Wow! Looking the fool, tell us about your magic dark matter and how Gravity makes black holes and Suns in the neutral vacum of your miraculous Big Bang?
Sounds like your on an angry bender, might lay off the sauce for awhile. It's pickeling your brain and making you a bit cunty.

TehDog
5 / 5 (2) Aug 10, 2015
@jonesdave
Your comments immediately reminded me of this :)
https://www.youtu...eRufrkxM

(Off topic, but hey, we all need a chuckle now and then :)
yep
1 / 5 (4) Aug 11, 2015
Peer review of a false a priori is little evidence of anything other then adults can believe in fairy tails. This is not the first time scientific thought has been based on assumption. These theory were decided when only the visible spectrum was available, it's time to move beyond the conceptions of the gaslight era.
jonesdave
3.7 / 5 (6) Aug 11, 2015
@jonesdave
Your comments immediately reminded me of this :)
https://www.youtu...eRufrkxM

(Off topic, but hey, we all need a chuckle now and then :)


Not wrong. Bloody good sketch, mind. Still, lets leave the EU nutters to play in their sandbox. Nobody takes it seriously; nobody ever will. Remember Velikovsky?
yep
1 / 5 (1) Aug 18, 2015
Still, lets leave the EU nutters to play in their sandbox. Nobody takes it seriously; nobody ever will. Remember Velikovsky?

Every day more articles http://phys.org/n...rth.html
It's almost beyond reason that you can believe the nonsense that passes for theory because it comes from "authority".

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