Einstein's theory of gravity holds – even in extreme conditions

July 4, 2018 by Laura Otto, University of Wisconsin - Milwaukee
The pulsar and the inner white dwarf fall in the gravitational pull of the outer white dwarf (in red). In most theories of gravity, the very strong gravity of the pulsar means it will fall with a different acceleration than the inner white dwarf. But Einstein’s theory predicts they should fall exactly the same way. Credit: Neil Blevins

Drop a marble and a cannon ball off the Leaning Tower of Pisa at the same time and they will hit the ground at the same time. That fact is explained by Albert Einstein's theory of gravity—general relativity—which predicts that all objects fall in the same way, regardless of their mass or composition.

Even the Earth and the moon "fall" in the same way toward the sun as they orbit each other.

Einstein's theory has passed all tests in laboratories and elsewhere in our solar . But scientists know that quantum mechanics behaves differently, so Einstein's theory has to break somewhere. Does this principle also hold for objects with extreme ?

The answer is "yes," according to an international team of astronomers, including one from the University of Wisconsin-Milwaukee. They have tested the question with the help of three orbiting each other in a natural "laboratory" about 4,200 light years from Earth.

Findings from the team, led by researchers at the University of Amsterdam and the Netherlands Institute for Radio Astronomy (ASTRON), are published today in Nature.

Triple star system

Their test subject is a system called PSR J0337+1715, consisting of a neutron star in a 1.6-day orbit with a white dwarf. This pair is in a 327-day orbit with another white dwarf farther away.

About the size of a planet, a white dwarf is a star that hasexhausted its nuclear fuel and only the hot core remains. While are small and dense, nothing beats the density of a neutron star, which is a cinder left over after a burned-out star has exploded. Its gravity has crushed the massive remains into a remnant the size of a city.

The neutron star becomes a pulsar when it spins rapidly and has a . Pulsars emit radio waves, X-rays or even optical light with each rotation.

The researchers made the measurement just by tracking the neutron star, a pulsar.

"It rotates 366 times per second, and beams of rotate along," said Anne Archibald, the paper's first author at ASTRON and the University of Amsterdam. "They sweep over the Earth at regular intervals, like a cosmic lighthouse. We have used these radio pulses to track the position of the neutron star."

White dwarf gravity

When the pulsar moves, something is causing it, said David Kaplan, an associate professor of physics at the University of Wisconsin-Milwaukee and a co-author on the paper. "If Einstein is correct, it has to be the gravity of the white dwarf it's circling that's making the pulsar move."

The team of astronomers followed the neutron star for six years using the Westerbork Synthesis Radio Telescope in the Netherlands, the Green Bank Telescope in West Virginia and the Arecibo Observatory in Puerto Rico.

If the neutron star fell differently from the white dwarf, the pulses would arrive at a different time than expected. But as far as the researchers know, that didn't happen. Archibald and her colleagues found that any difference between the accelerations of the star and white dwarf is too small to detect.

This system offers the researchers the opportunity to test the nature of gravity with much more sensitivity, said Kaplan, who was among the researchers who first published on the system that was discovered in 2012.

"We've done better with this system than previous tests by a factor of 10," said Kaplan. "But it's not an ironclad answer. Reconciling gravity with is still unresolved."

Can't ignore relativity

A more precise description of gravity is important for other reasons too, said Kaplan.

"If you ignored general relativity but then tried to use the GPS on your phone, you'd end up far from your destination," he said. "But we're also trying to understand how the universe works here. We still don't understand how stars move."

Advancements in radio telescopes offer more chances at finding the perfect triple system to test, said Jason Hessels, associate professor at ASTRON and the University of Amsterdam.

If the Square Kilometre Array is built in Australia and South Africa as planned, it would be the largest radio telescope in the world, capable of finding many more millisecond pulsars as are now known in our galaxy.

"Among these yet undiscovered systems may lurk even more powerful tools for understanding the universe," Hessels said. "Perhaps one of these may provide our first peek at a theory beyond Einstein's."

Explore further: New pulsar discovered during a search for a companion to a low-mass white dwarf

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rossim22
2.8 / 5 (13) Jun 28, 2018
Einstein's theory of gravity doesn't even hold in any observable galaxy.

When there's not enough observable matter... just invent dark matter! (0 direct observations)

When there's too much gravity... just invent the possibility of neutron stars! (0 direct observations)

When gravity doesn't agree with red shift... just create dark energy! (0 direct observations)

I can't wait for what other ad hoc tales will be told in the near future.
PTTG
3.7 / 5 (7) Jul 04, 2018
@Rossim22, You have a clinially treatable disorder that causes you to see conspiracy where there is none. I hope that you seek treatment, if not for your benefit, then for those around you.
Reg Mundy
1.4 / 5 (11) Jul 04, 2018
@rossim22
You missed a few other discrepancies, but even demonstrable total failure of gravity theories has no impact on the scientific community. We need a new theory that doesn't rely on a mystical non-existent force that can't be seen/affected/blocked/generated/detected and was invented by Newton to explain something that any sensible person (i.e. not under the influence of whatever he was smoking) could see was caused by the expansion of the Earth.
Hyperfuzzy
1.6 / 5 (7) Jul 04, 2018
Last I checked; it is impossible to prove Gravity as a separate force of Nature, given the existence of charge! Who does validation? Not to mention a literally phony theory, i.e. lost in Mach's world of validation without Logic! We're living in a world of trained parrots, who repeat but have no idea of the sheer nonsense! Is this some kind of test to prove who's worthy? i.e.since charge is necessary and sufficient to create the entire universe and all actions! QED
V4Vendicar
1.6 / 5 (7) Jul 04, 2018
"Drop a marble and a cannon ball off the Leaning Tower of Pisa at the same time and they will hit the ground at the same time. That fact is explained by Albert Einstein's theory of gravity—general relativity—which predicts that all objects fall in the same way, regardless of their mass or composition." - Article

Einsteinian gravity predicts the exact opposite of course.

Newtonian gravity makes the prediction Einstein does not agree with newton.

Hyperfuzzy
3 / 5 (2) Jul 04, 2018
"Drop a marble and a cannon ball off the Leaning Tower of Pisa at the same time and they will hit the ground at the same time. That fact is explained by Albert Einstein's theory of gravity—general relativity—which predicts that all objects fall in the same way, regardless of their mass or composition." - Article

Einsteinian gravity predicts the exact opposite of course.

Newtonian gravity makes the prediction Einstein does not agree with newton.


You don't get it! If charge exists unique polar points, defining all things, then any other force is unnecessary, i.e. Gravity is not a separate force of Nature! QED
Reg Mundy
1 / 5 (6) Jul 05, 2018
My first book ("The Secret of Gravity",1997) was based on an electronic model of the hydrogen atom. The hydrogen atom has two electric charges, and electron and a proton. Several different electron orbit configurations were proposed, and the Coulomb forces of attraction were shown to conform to the force of gravity. I later found that Planck's original quantum theory (which preceded Einstein's theory) was also based on an electrical model of the atom. The correlation is dependent on the electron orbit configuration, and my further investigation, over the next decade, produced a more accurate atom model and a proper orbit configuration that also conforms to the mechanical characteristics..

Interesting. Is it still in print? You might be interested in my "The Situation of Gravity" which offers a fundamentally different explanation for the phenomena we attribute to "gravity".
Merrit
5 / 5 (1) Jul 05, 2018
I can't tell if people are being trolls or seriously believe what the write.
Hyperfuzzy
1 / 5 (2) Jul 05, 2018
@Rossim22, You have a clinially treatable disorder that causes you to see conspiracy where there is none. I hope that you seek treatment, if not for your benefit, then for those around you.

You did not show your logic that refutes his claim! Why, is your response necessary and sufficient? Am I being disrespectful? Are you? For your information I find disrespect, illogical thinking the thinking of the un-evolved, madmen, idiots for those without logic have an unguided mind and are a danger to themselves and others.
wduckss
1 / 5 (5) Jul 06, 2018

"Einstein.. holds that gravity is a consequence of space-time's inherent flexibility: Massive objects distort the cosmic fabric, creating a sort of well around which other bodies orbit.

It is interesting that "scientists" today believe in these nonsense."

https://www.acade..._objects
"Jupiter has over 60 satellites and rings, Pluto has 5 satellites, Venus and Mercury have no satellite. Where is Einstein, his gravity and his theory?
"The objects with a ring but without their own rotation have never been dicovered yet. .. All satellites of the Solar system, together with Mercury and Venus, could also be included here, with the important remark that very low temperatures and irregular shape of the distant satellites in the Kuiper belt around planets can also have their own rotation, as well as the objects around that satellite.
..having a disk.. are very fast rotating stars..
milnik
1.7 / 5 (6) Jul 06, 2018
The general theory of relativity, as well as the Lorentz transformation, rest on the fancies of their authors, who at all costs have tried to prove their unnatural and fictitious ways of understanding phenomena that they have no true proof. To understand the concept of gravity and magnetism as two basic phenomena in the universe, we must know the following: there is no empty space in the universe, there are no virtual particles, there is no BB, the universe does not expand, there is no dark matter, there is no dark energy.
There is an infinite universe filled with the substance Aether from which the matter is formed in two forms. These two types of matter with Aether have a "family" relationship, which is gravity and magnetism.
milnik
1 / 5 (4) Jul 06, 2018
Gravity has the task of returning matter back into the form of Aether from which the matter is formed (black holes), and magnetism is the basis of all forms of energy and wave, and without magnetism there is no explanation for the formation of the squared gluon plasma, light, heat, radiation, wave, and everything related to behavior and many phenomena in heavenly bodies.
The space is a place for the accommodation of matter and its movement according to the laws assigned, and time is only a measure of that movement. Run away from Einstein, if you think anything in the universe.
Hyperfuzzy
not rated yet Jul 06, 2018
I can't tell if people are being trolls or seriously believe what the write.

Belief and Logic, two different things.
Hyperfuzzy
not rated yet Jul 06, 2018
THINK w/ Logic
wduckss
1 / 5 (3) Jul 06, 2018
With the attractive forces of matter, body rotation is the central process of forming and creating the system and the universe.
If the body has independent rotation, it has smaller bodies in orbit. If there is no rotation there is no orbit. That's elementary evidence.
The logic here is not important.
Maybe your logic offers counter evidence? Please list some evidence, at least one.
I do not admit "said Einstein" etc.
Hyperfuzzy
not rated yet Jul 06, 2018
With the attractive forces of matter, body rotation is the central process of forming and creating the system and the universe.
If the body has independent rotation, it has smaller bodies in orbit. If there is no rotation there is no orbit. That's elementary evidence.
The logic here is not important.
Maybe your logic offers counter evidence? Please list some evidence, at least one.
I do not admit "said Einstein" etc.

You're not making sense!
Hyperfuzzy
not rated yet Jul 07, 2018
If anyone, follows; None of it makes any sense? Correct? Or am I just the only one? The only one that requires logic; Premise, Logical Proof of --- wait WTF! c as in ExH? It's a constant of propagation! huh? G from m and m some function of Velocity then WTF? Ieeeeee! Who let the mad dog loose?

I require more than one Amen! But know Amen for his Logic. Else, ..
humy
5 / 5 (3) Jul 07, 2018
I can't tell if people are being trolls or seriously believe what they write.

I am afraid for many posters its both.
Terrible.
wduckss
5 / 5 (1) Jul 07, 2018
@Hyperfuzzy Classics. Ignorance against evidence. You offer only empty rhetoric without any evidence. Ah, yes, you do not need proof. You are above the evidence.
Hyperfuzzy
1 / 5 (1) Jul 07, 2018
;
@Hyperfuzzy Classics. Ignorance against evidence. You offer only empty rhetoric without any evidence. Ah, yes, you do not need proof. You are above the evidence.

Evidence: Charge exists! Drives all of modern tech; you my friend, without bias, are stupid! anyway, juz having fun. what else ya got?
Hyperfuzzy
not rated yet Jul 29, 2018
;
@Hyperfuzzy Classics. Ignorance against evidence. You offer only empty rhetoric without any evidence. Ah, yes, you do not need proof. You are above the evidence.

Evidence: Charge exists! Drives all of modern tech; you my friend, without bias, are stupid! anyway, juz having fun. what else ya got?

Therefore any other force is derivative. QED

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