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General relativity passes a range of precise tests set by pair of extreme stars

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Re: General relativity passes a range of precise tests set by pair of extreme stars

#21

Post by raffraffraff »

behnamoh wrote: post #10
mensetmanusman wrote: post #5

“ This cosmic laboratory known as the “Double Pulsar” was discovered by members of the team in 2003. It consists of two radio pulsars which orbit each other in just 147 min with velocities of about 1 million km/h. One pulsar is spinning very fast, about 44 times a second. The companion is young and has a rotation period of 2.8 seconds. It is their motion around each other which can be used as a near perfect gravity l…

My jaw (and my phone) dropped when I read the numbers. I feel like space is ruthlessly huge and these pulsars are brutally massive..

https://en.m.wikipedia.org/wiki/TON_618

This black hole is 66 billion solar masses. Its mass is greater than that of our entire galaxy. The quasar shines with the power of 140 trillion suns. The event horizon radius is times 40 times the distance from Neptune to the Sun. Matter is getting sucked into it at 7000km/s

Re: General relativity passes a range of precise tests set by pair of extreme stars

#23

Post by gran_colombia »

fmajid wrote: post #18

It's not as if anyone was expecting General Relativity to fail the test. Gravitational time dilation is a thing observed since the 1970s, atomic clocks have compensation for altitude and gravitational potential applied to them and that's part of the TAI and UTC standards we use every day, knowingly or not. On the other hand, Einstein lost his vendetta against Quantum physics, badly, since Alain Aspect's 1980 experime…

Einstein did not really have a vendetta against Quantum physics. He won a Nobel for having established the basic theory of the photoelectric effect. I know what you mean, but it's not like he thought the idea was ridiculous, he came up with it in his youth.

Re: General relativity passes a range of precise tests set by pair of extreme stars

#24

Post by m3kw9 »

raffraffraff wrote: post #21
behnamoh wrote: post #10

Earlier quoted context omitted.

My jaw (and my phone) dropped when I read the numbers. I feel like space is ruthlessly huge and these pulsars are brutally massive..

https://en.m.wikipedia.org/wiki/TON_618 This black hole is 66 billion solar masses. Its mass is greater than that of our entire galaxy. The quasar shines with the power of 140 trillion suns. The event horizon radius is times 40 times the distance from Neptune to the Sun. Matter is getting sucked into it at 7000km/s

This is why we need to develop very precise warp drive exit techniques. Don’t want to exit warp inside the horizon.

Re: General relativity passes a range of precise tests set by pair of extreme stars

#25

Post by cbm-vic-20 »

raffraffraff wrote: post #21
behnamoh wrote: post #10

Earlier quoted context omitted.

My jaw (and my phone) dropped when I read the numbers. I feel like space is ruthlessly huge and these pulsars are brutally massive..

https://en.m.wikipedia.org/wiki/TON_618 This black hole is 66 billion solar masses. Its mass is greater than that of our entire galaxy. The quasar shines with the power of 140 trillion suns. The event horizon radius is times 40 times the distance from Neptune to the Sun. Matter is getting sucked into it at 7000km/s

TON 618 is a quasar, which according to Wikipedia "is an extremely luminous active galactic nucleus (AGN), powered by a supermassive black hole, with mass ranging from millions to tens of billions of solar masses"

"More than a million quasars have been found".

Wild.

Re: General relativity passes a range of precise tests set by pair of extreme stars

#26

Post by hbrav »

dotancohen wrote: post #15
behnamoh wrote: post #10

Earlier quoted context omitted.

My jaw (and my phone) dropped when I read the numbers. I feel like space is ruthlessly huge and these pulsars are brutally massive..

Additionally, I love the challenge to language. These stars _are_ massive... but also tiny. Compare their 24 km radius to the 600,000 km radius of the sun. One of these objects would sit comfortably inside many Earth cities. ... at least for a milisecond before destroying it.

If you see "massive" in reference to an astronomical object, it usually means "having a lot of mass" rather than "being very big".

Not always of course, and the latter usage is more likely in less specialized news sources.

Re: General relativity passes a range of precise tests set by pair of extreme stars

#27

Post by ziddoap »

raffraffraff wrote: post #21
behnamoh wrote: post #10

Earlier quoted context omitted.

My jaw (and my phone) dropped when I read the numbers. I feel like space is ruthlessly huge and these pulsars are brutally massive..

https://en.m.wikipedia.org/wiki/TON_618 This black hole is 66 billion solar masses. Its mass is greater than that of our entire galaxy. The quasar shines with the power of 140 trillion suns. The event horizon radius is times 40 times the distance from Neptune to the Sun. Matter is getting sucked into it at 7000km/s

As with most amazing space-related things, Anton Petrov has a wonderful video talking about TON 618, using Universe Sandbox (which is quite fun to play in!) to demonstrate its size in comparison to our solar system. It helps, to an extent, to visualize just how large it is.

https://www.youtube.com/watch?v=Vn9Xuema8q4

Re: General relativity passes a range of precise tests set by pair of extreme stars

#28

Post by nimish »

fsh wrote: post #7
waynecochran wrote: post #2

Fantastic! Was the orbit of Mercury early in the 20th centruy the first confirmation?

It was known since the 1850s that the perihelion precession of Mercury is a few percent larger than predicted by Newtonian mechanics. This even led to speculations that there might be another undiscovered planet ("Vulcan") in a close orbit around the sun. In 1916 Einstein calculated that this effect could be fully explained by General Relativity. Another famous prediction is that of the deflection of light that passe…

Light deflection happens in newtonian physics as well, assuming you use Newton's definition of light as a particle/corpuscule: https://physics.stackexchange.com/questions/29837/does-newto...

It's just 2x the GR value. That's one reason why it took so long to verify as you needed to have pretty clean data to rule out the classical explanation.

Re: General relativity passes a range of precise tests set by pair of extreme stars

#29

Post by pbuzbee »

raffraffraff wrote: post #21
behnamoh wrote: post #10

Earlier quoted context omitted.

My jaw (and my phone) dropped when I read the numbers. I feel like space is ruthlessly huge and these pulsars are brutally massive..

https://en.m.wikipedia.org/wiki/TON_618 This black hole is 66 billion solar masses. Its mass is greater than that of our entire galaxy. The quasar shines with the power of 140 trillion suns. The event horizon radius is times 40 times the distance from Neptune to the Sun. Matter is getting sucked into it at 7000km/s

Small nit: I think the Wikipedia entry is saying TON 618's mass is greater than all of the stars in our galaxy (6*10^10 solar masses, according to the article), not greater than the entire mass of the galaxy (~10^12 solar masses, according to the Milky Way article).

Re: General relativity passes a range of precise tests set by pair of extreme stars

#30

Post by fsh »

nimish wrote: post #28
fsh wrote: post #7

Earlier quoted context omitted.

It was known since the 1850s that the perihelion precession of Mercury is a few percent larger than predicted by Newtonian mechanics. This even led to speculations that there might be another undiscovered planet ("Vulcan") in a close orbit around the sun. In 1916 Einstein calculated that this effect could be fully explained by General Relativity. Another famous prediction is that of the deflection of light that passe…

Light deflection happens in newtonian physics as well, assuming you use Newton's definition of light as a particle/corpuscule: https://physics.stackexchange.com/questions/29837/does-newto... It's just 2x the GR value. That's one reason why it took so long to verify as you needed to have pretty clean data to rule out the classical explanation.

I don't think that anyone took the corpuscular theory of light seriously after its wave nature had been discovered in the early 19th century. In classical electrodynamics, light is completely unaffected by gravity.
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