Pulsars with black holes could hold the 'holy grail' of gravity

December 4, 2014, Plataforma SINC
Discovering a pulsar orbiting a black hole could be the ‘holy grail’ for testing gravity. / Credit: SKA Organisation/Swinburne Astronomy Productions

The intermittent light emitted by pulsars, the most precise timekeepers in the universe, allows scientists to verify Einstein's theory of relativity, especially when these objects are paired up with another neutron star or white dwarf that interferes with their gravity. However, this theory could be analysed much more effectively if a pulsar with a black hole were found, except in two particular cases, according to researchers from Spain and India.

Pulsars are very dense that are the size of a city (their radius approaches ten kilometres), which, like lighthouses for the universe, emit gamma radiation beams or X-rays when they rotate up to hundreds of times per second. These characteristics make them ideal for testing the validity of the theory of general relativity, published by Einstein between 1915 and 1916.

"Pulsars act as very precise timekeepers, such that any deviation in their pulses can be detected," Diego F. Torres, ICREA researcher from the Institute of Space Sciences (IEEC-CSIC), explains to SINC. "If we compare the actual measurements with the corrections to the model that we have to use in order for the predictions to be correct, we can set limits or directly detect the deviation from the base theory."

These deviations can occur if there is a massive object close to the pulsar, such as another neutron star or a white dwarf. A white dwarf can be defined as the stellar remnant left when stars such as our Sun use up all of their nuclear fuel. The binary systems, comprised of a pulsar and a neutron star (including double pulsar systems) or a white dwarf, have been very successfully used to verify the theory of gravity.

Last year, the very rare presence of a pulsar (named SGR J1745-2900) was also detected in the proximity of a (Sgr A*, made up of millions of solar masses), but there is a combination that is still yet to be discovered: that of a pulsar orbiting a 'normal' black hole; that is, one with a similar mass to that of stars.

Until now scientists had considered this strange pair to be an authentic 'holy grail' for examining gravity, but there exist at least two cases where other pairings can be more effective. This is what is stated in the study that Torres and the physicist Manjari Bagchi, from the International Centre of Theoretical Sciences (India) and now postdoc at the IEEC-CSIC, have published in the 'Journal of Cosmology and Astroparticle Physics'. The work also received an Honourable Mention in the 2014 Essays of Gravitation prize.

The first case occurs when the so-called principle of strong equivalence is violated. This principle of the indicates that the gravitational movement of a body that we test only depends on its position in space-time and not on what it is made up of, which means that the result of any experiment in a free fall laboratory is independent of the speed of the laboratory and where it is found in space and time.

The other possibility is if one considers a potential variation in the gravitational constant that determines the intensity of the gravitational pull between bodies. Its value is G = 6.67384(80) x 10-11 N m2/kg2. Despite it being a constant, it is one of those that is known with the least accuracy, with a precision of only one in 10,000.

In these two specific cases, the pulsar-black hole combination would not be the perfect 'holy grail', but in any case scientists are anxious to find this pair, because it could be used to analyse the majority of deviations. In fact, it is one of the desired objectives of X-ray and gamma ray space telescopes (such as Chandra, NuStar or Swift), as well as that of large radio telescopes that are currently being built, such as the enormous 'Square Kilometre Array' (SKA) in Australia and South Africa.

Explore further: Pulsar in stellar triple system makes unique gravitational laboratory

More information: Manjari Bagchi y Diego F. Torres. "In what sense a neutron star−black hole binary is the holy grail for testing gravity?". Journal of Cosmology and Astroparticle Physics, 2014. DOI: 10.1088/1475-7516/2014/08/055.

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cantdrive85
1.6 / 5 (21) Dec 04, 2014
"If we compare the actual measurements with the corrections to the model that we have to use in order for the predictions to be correct, we can set limits or directly detect the deviation from the base theory."


LOL, "corrections to the model that we have to use in order for the predictions to be correct", the standard theory in a nutshell.
Scroofinator
1 / 5 (6) Dec 04, 2014
And you measure your weight with a voltmeter!!!

Oh, so you have figured out what mass is then? Pray tell...
Modernmystic
4.3 / 5 (12) Dec 04, 2014
"If we compare the actual measurements with the corrections to the model that we have to use in order for the predictions to be correct, we can set limits or directly detect the deviation from the base theory."


LOL, "corrections to the model that we have to use in order for the predictions to be correct", the standard theory in a nutshell.


Actually that's SCIENCE in a nutshell. You think that even IF your EU theories are correct that they are the end of all knowledge of the cosmos?
Scroofinator
5 / 5 (3) Dec 04, 2014
Correct me if I'm wrong, but isn't weight calculated by W=mg?
Scroofinator
5 / 5 (2) Dec 04, 2014
Probably correct at the moment

Not probably, it is.
cantdrive85
1.7 / 5 (11) Dec 04, 2014
will have you believe that pulsars are formed by a plasma focusing device - basically a giant rotating hollow brass electrode,


This is the typical obfuscation of the truth as presented by liars. If you actually read it or could understand what you read you would realize what he said is;

"If beaming of the radiation is occurring then that should be verifiable here on Earth in the lab by studying the plasma focus device."

The PFD is a laboratory device which mimics the natural processes of a plasma focus in a cosmic Birkeland current. Maybe with your ridiculous reasoning you could explain how a Tokamak device is supposed to tell us more about solar fusion.

Scroofinator
3 / 5 (4) Dec 04, 2014
The history of science is littered with carcases of dead theory

And many of those theories were accepted at one point.
http://en.wikiped...theories
My favorite is the Caloric theory. Completely wrong assumption of a fluid, yet it's predictions still proved extremely accurate.

Gravity might be another case of "right effect, wrong cause"
Scroofinator
1 / 5 (3) Dec 04, 2014
Are you trying to say you like to wear lipstick? Not much of a conspiracy...
cantdrive85
1.3 / 5 (11) Dec 04, 2014
@cantdrive85 -
This is the typical obfuscation of the truth as presented by liars
Wrong. It's a joke, placed there to pull someone's leg a little. Seems to have hit the mark...


It's funny you see experimentation as a joke, but then again you do prefer the purely theoretical approach of the standard theory.

viko_mx
1.5 / 5 (8) Dec 05, 2014
I wonder why we have to stick to the theory of GR to solve problems related to gravity? Why gravity must be related to deformed space when this force can safely and easily act in a static space? Once the vacuum of space is the transmission medium of the other known power interactions between constituent particles of matter, why the gravitational interaction to make an exception? With what this theory made cosmology more understandable and successful in understanding the secrets of the cosmos and predicting the behavior of cosmic bodies in it? If only because the idea that space should be expanded to may the universe arise from some cosmic singularity apeared from nothing by itself, and to exclude the role of the Creator for the emergence of the universe, is understandable such desire and persistence in the scientific community, but is unconvincing. On what foundation is built theory of GR and what was the scientific necessity of its creation? What problems solve and what it can't?
cantdrive85
1.4 / 5 (10) Dec 05, 2014
So, rock-carvings or engravings by, presumably, prehistoric peoples are to be taken as the starting point of the EU "story".


Yep, and it has been shown in peer-reviewed research that the eyewitness accounts and the rock art they left behind from across the planet agree with this premise.

http://www.plasma...rth.html

You can choose to ignore the volumes of information humans have recorded throughout the history of humanity, or one can analyze this information scientifically then apply it to a cosmology to see how it fits the data. Strangely enough this part of Earth/human history fits perfectly in the EU/PC paradigm.
jsdarkdestruction
5 / 5 (5) Dec 05, 2014
On what foundation is built theory of GR and what was the scientific necessity of its creation? What problems solve and what it can't?

http://en.wikiped...lativity
Captain Stumpy
4 / 5 (12) Dec 05, 2014
I said weight. Weight - not mass. Pay attenshun.
@FineStructureConstant
i am doubtful that hyperbole would be something that they would be able to figure out, given how subtle it is and all...

as proven by scroof's and reset's posts afterward

the post is quite cogent, considering the players involved... thanks for pointing this out, FSC! you are actually demonstrating why they believe in pseudoscience !!
a brilliant tactic. i will have to remember this one!

All i can say is..."WOW!"
http://sci-ence.o...-flags2/

you leave a lipstick tube open near a chimpanzee, they will do all sorts of things with it. Including use it as lipstick.
Doesn't mean it works.
@Pandora4real
you have just described eu to a "T"
best description yet
Thanks
viko_mx
1.8 / 5 (5) Dec 06, 2014
@FineStructureConstant

Did you say something or just demonstrated the presence in the forum? If you have nothing to say on the subject why you feel obliged to comment on other participants in the forum?
Vietvet
4.2 / 5 (10) Dec 06, 2014
@viko mx

@FineStructureConstant

Did you say something or just demonstrated the presence in the forum? If you have nothing to say on the subject why you feel obliged to comment on other participants in the forum?


Why do you spout creator nonsense on a science site?
viko_mx
2.6 / 5 (5) Dec 06, 2014
@FineStructureConstant

Why do you think that I have not studied physics In the university? You can not know my qualifications. Do everything that I studied at university must accept as truth? In fact why to learn useless knowledge or theories which do not help scienties to develop a clearer picture of the world in which we live? Such theories only provide a favorable environment for careerism and are defended vigorously exactly by that kind of people for who wage and comfort in their scientific community are more important than scientific truth.
antialias_physorg
4.6 / 5 (9) Dec 06, 2014

Why do you think that I have not studied physics In the university?

Hint: Everything you write. Really. All of that screams "I have never touched a physics book in my life". If you have studied hysicsat a university that must be the worst university in the world - and even then you may have studied it: but you shure as hell didn't pass.

In fact why to learn useless knowledge or theories which do not help scienties to develop a clearer picture of the world in which we live?

Hint: GR does exactly that: It gives us a clearer picture where there were a lot of things before that didn't mesh with the theories of the time.

If you can't cope with learning the clear physical theories then that's your own problem.
viko_mx
2.3 / 5 (6) Dec 06, 2014

@ antialias_physorg

Do you know the properties of the cosmic vacuum and under what circumstances can be changed locally or globally? These properties determine the transmission of force interactions between constituent particles of matter. Can this environment constantly changes by endless expanding, without changing its physical properties? From where originates energy for this expansion? For what to learn theories that preach such absurd ideas? Do you have any idea what exactly is the vacuum of space to can defend with self confidence such idea for elastic space? I have no problem with physics but with imposed theories with gambling spirit?
DeliriousNeuron
1.4 / 5 (10) Dec 06, 2014
Piss off Stumpydick!
Until then, read up on plasma cosmology. It will do you a world of good. Then you won't look like such an ass. Then you'll be able to constructively contribute on these discussions.
Same for the rest of you mainstreamers.

Electricity is all around you at ALL scales. Open your eyes people!
imido
Dec 06, 2014
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imido
Dec 06, 2014
This comment has been removed by a moderator.
imido
Dec 06, 2014
This comment has been removed by a moderator.
Captain Stumpy
4.2 / 5 (10) Dec 06, 2014
@DN -
Piss off Stumpydick!
- and we have a winner! Or should that be Whiner, or Wiener?

It's truly rich that I'm being asked to vacate a PHYSICS forum by a believer in mythology-based pseudoscience. No way, Cupcake, I'm having too much fun.
@FineStructureConstant
Actually, i think she was referring to me... she has said, in the past
DeliriousNeuron
1 / 5 (2) 12 hours ago
I'm just gonna troll you exclusively from now on ok Stumpydick? Don't be mad! Screw science for now!

Read more at: http://phys.org/n...html#jCp
so, i have a GROUPIE

too bad she is an eu acolyte

Keep up the great work, regardless FSC!
you are bang on and making the eu idiots look bad!

BTW - i loved this link as well
http://math.ucr.e...pot.html

a regular read while observing eu posts
always good for spotting the cranks, from alfvie and cd to reg and prins
DeliriousNeuron
1 / 5 (8) Dec 06, 2014
Well....did u spend the day educating yourselves? Obviously not.
Get to work! Test Monday morning.
cantdrive85
1.9 / 5 (9) Dec 06, 2014
Well....did u spend the day educating yourselves? Obviously not.
Get to work! Test Monday morning.


He let someone else convince him Plasma Cosmology is "pseudoscience", so now as far as he's concerned it's been "proven". That'll be the end of his "education" as he is incapable of thinking for himself. Even if he read the many peer-reviewed papers he wouldn't understand them, without a book titled 'PC for Dummies' he will be "perplexed". As such, he will never attempt to answer a specific scientific question in his own words, he will only attach a link he believes has some relevance as the "proof". As far as he's concerned, whatever the "generally accepted" theory or democratically determined most popular "theory" happens to be, he will defend it without any basic understanding whatsoever and will assume it is "settled". He naively believes science is perfect and cannot be wrong in this "day and age". He has the rubes disease, he's Cap'n Stupid!
viko_mx
1.8 / 5 (5) Dec 07, 2014
@FineStructureConstant

You tell me is there any specialist with enough self confidence, who claims he understands sufficiently quantum mechanics? Your comments on the position of such a specialist you are? Complex and controversial does not mean correct. Usually things are not as complicated as are present by main stream scientists, but you must have intuition and sober thought to understand them. It is enough for most people to understand only those theories which makes sense and are based on logic and the results of direct observations and experiments.
Protoplasmix
4.5 / 5 (6) Dec 07, 2014
In fact, it [pulsar-BH combo] is one of the desired objectives of X-ray and gamma ray space telescopes (such as Chandra, NuStar or Swift), as well as that of large radio telescopes that are currently being built, such as the enormous 'Square Kilometre Array' (SKA) in Australia and South Africa.

The SKA will also be able to detect airport radar on a planet 50 light years away (ref). The current count of terrestrial exoplanets within 50 ly is at 26, and 10 of them are likely within their star's habitable zone (ref).

You'd have to ask the eu/pc folks if they've calculated how many amps of Birkeland current or megatons of exploding double layers the SKA might detect. I dunno.
Egleton
2.1 / 5 (7) Dec 07, 2014
From an autodidacts point of view it does seem as if physics is at the stage where it is trying to count the number of fairies that can dance on the end of a pin.
The Higgs can explain mass and therefore inertia? So there is this "field" thingy that ensures that an object in motion stays in motion unless acted on by another object?
Yes! I can see the light!
Just kidding.
And why do we not insist that an electric field also bends space time? Why do I not see a distortion of light if I stand in a magnetic field?
Methinks she doth protest too much.
No-one proclaims loudly that the sun will rise tomorrow. Science is lacking the quiet self confidence that would be reassuring.
But then who is confident when dancing along the edge of the Abyss?
imido
Dec 07, 2014
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Protoplasmix
5 / 5 (6) Dec 07, 2014
Relativity definition: a theory demonstrating the constant speed of light with violation of constant speed of light (gravitational lensing).

Lensing changes the direction of light's velocity, not the magnitude, so no violation.
imido
Dec 07, 2014
This comment has been removed by a moderator.
imido
Dec 07, 2014
This comment has been removed by a moderator.
imido
Dec 07, 2014
This comment has been removed by a moderator.
Protoplasmix
4.2 / 5 (5) Dec 07, 2014
Counterexamples of general relativity.

Did you bump your head, iZeph? General relativity is part of a liberal agenda? Quoting from the "Conservapedia":

"14. Despite wasting millions of taxpayer dollars searching for gravitational waves predicted by the theory, no direct observation of gravity waves has occurred.[17] Sound like global warming? Then, in classic liberal claptrap, the liberal media claimed that gravitational waves were discovered when in fact no such direct observation was made."
. . .

"21. The action-at-a-distance by Jesus, described in John 4:46-54, Matthew 15:28, and Matthew 27:51."


That settles that. Beat your interferometers into laser pointers and turn away from your pulsars ye sinners, for man (and his binders full of women) keep time not by relativity alone, but by every word greedy conservative tyrants speak.
Captain Stumpy
4.4 / 5 (7) Dec 08, 2014
Mainstream physics is more religion based, than one may think at the first sight: http://arstechnic...y-facts.
@ZEPHIR
Thank you for FINALLY proving that your posts are all about your religious/political beliefs and the inability to accept reality because of your decision to accept a falsified belief
According to a new study in the Journal of Personality and Social Psychology, unfalsifiability is an important component of both religious and political beliefs. It allows people to hold their beliefs with more conviction, but it also alows them to become more polarized in those beliefs
[sic] this is demonstrated no better than your belief in daw/aw which is falsified here: http://exphy.uni-...2009.pdf

zeph=pseudoscience troll
Elmo_McGillicutty
2 / 5 (4) Dec 08, 2014
There is no such thing as mass, it is only apparent. Mass is made up of inertia and angular momentum. Both inertia and angular momentum vary with energy level.

Then angular momentum of what then?

Charge. There is only one physical entity in the universe. Charge.
Selena
Dec 08, 2014
This comment has been removed by a moderator.
Selena
Dec 08, 2014
This comment has been removed by a moderator.
Selena
Dec 08, 2014
This comment has been removed by a moderator.
Captain Stumpy
3.8 / 5 (10) Dec 08, 2014
@ZEPHIR aka imido aka selena
In AWT the dualities at
you must be getting ready to be banned and setting up your next two sock puppets!
aw/daw is a religion and PSEUDOSCIENCE, not science
repeating your claims here does NOT make it any more real
aw/daw is falsified here: http://exphy.uni-...2009.pdf

aw/daw is NOT a theory, it is PSEUDOSCIENCE and proven to be thus above with that link

You have never been able to provide empirical evidence supporting your religion of aw/daw without referencing your reddit personal site or other pseudoscience sites

there is NO reputable evidence

and you will be banned AGAIN eventually
(don't forget to 1-star this so the nooB's can play "spot the looney" or "spot the TROLL")
http://sci-ence.o...-flags2/
Protoplasmix
5 / 5 (7) Dec 08, 2014
This is just a religious sh*t, denying another religious sh*t. The people are incredibly inventive, if they're have an opportunity to get the money and/or social influence for fabling instead of thinking. This applies to both mainstream relativists, both religious conservatives.

Hardly. Science is a proven methodology for discovering bits and pieces of truth, while religion is the (usually violent) insistence that some person or group is the sole authority on all matters of truth. The pursuit of science is freedom, while religion is the intolerant chains of tyranny. Science encourages growth and change of itself, while religion reacts to dissent in a blind fury to permanently silence it. Science is seeing the universe atop the shoulders of giants, while religion is the blind leading the blind...
Egleton
1 / 5 (4) Dec 11, 2014
Hi Proto.
Why do all scientists have such a cartoon version of religion? It gets a bit tiresome seeing the same old strawman being trotted out endlessly.
Go ahead and attack the strawman, it wont do any harm to religion.
Selena
Dec 11, 2014
This comment has been removed by a moderator.
Selena
Dec 11, 2014
This comment has been removed by a moderator.
Selena
Dec 11, 2014
This comment has been removed by a moderator.
Selena
Dec 11, 2014
This comment has been removed by a moderator.
Selena
Dec 11, 2014
This comment has been removed by a moderator.

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