# Has general relativity been put to the test?

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#### Missynmax83

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##### Has general relativity been put to the test?
« on: 06/12/2013 04:53:25 »
has there ever been tests in space to test general relativity at it most basic raw form at free orbit and try to orbit a small ball mass around a bigger heavyer ball mass (say like LAGEOS) i ask this coz at some point the cores of suns,planet would be at this size and if mass = gravity there is no reason for a test like to not work....now for any reason for this not to work coz of ow sun,moon or earth,wouldnt that mean over billions of years the sun,planets and ow black hole would have the same affect on the moon meaning we could have orbiting moons........ in my eyes if general relativity fails this simple test ,thats it ,its failed
« Last Edit: 06/12/2013 18:00:34 by chris »

#### RD

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##### Re: testing general relativity
« Reply #1 on: 06/12/2013 05:50:32 »
has there ever been tests in space to test general relativity at it most basic raw form at free orbit and try to orbit a small ball mass around a bigger heavyer ball mass (say like LAGEOS) ...

or like GPS ...
Quote from: wikipedia.org/Global_Positioning_System
In 1956, the German-American physicist Friedwardt Winterberg proposed a test of general relativity (for time slowing in a strong gravitational field) using accurate atomic clocks placed in orbit inside artificial satellites. (Later, calculations using general relativity determined that the clocks on GPS satellites would be seen by Earth's observers to run 38 microseconds faster per day, and this was corrected for in the design of GPS.)
https://en.wikipedia.org/wiki/Global_Positioning_System#History

#### Missynmax83

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##### Re: testing general relativity
« Reply #2 on: 06/12/2013 06:31:51 »
hi RD ..... i dont debat the affects on time coz of gravity.

#### CliffordK

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##### Re: testing general relativity
« Reply #3 on: 06/12/2013 07:24:18 »
There have been many gravity experiments, for example the Grace Project for mapping Earth's gravity from space.

Of course, being in space is not without gravity, which can actually be quite significant depending how close one is to various celestial objects.  For example, the international space station is subjected to nearly the same gravity as one would have at the surface of the earth.  Just the orbit is a perfect balance between gravity and centrifugal force, giving the sensation of weightlessness.

You might have difficulties getting two objects sent up from Earth to orbit each other as most satellites weigh less than a few tons.

$$F=G\frac{m_1m_2}{r^2}$$

$$G=6.67384 x 10^{-11} N (\frac{m}{kg})^2$$

$$F=ma$$

$$a = \frac{F}{m}$$

So, say we had two 1000kg masses, spaced 1m apart.

We get: $$F = 6.67384 x 10^{-11} (\frac{1000^2}{1^2})$$

$$F = 6.67384 x 10^{-5} N$$

$$a = 6.67384 x 10^{-8} \frac{m}{s^2}$$

Anyway, for the two, one-ton objects, with a 1m space (between the centers), the acceleration towards each other is awfully small.

They may still orbit each other, but it would take a couple of years per orbit.

Also, keep in mind that the volume/mass of an object increases with the cube of the radius.  So, the gravity is essentially greater for the same distance from the surface for larger objects.

Anyway, for any practical experiments, one needs much bigger masses, thus using the sun, earth, moon, or perhaps some asteroids.

#### Missynmax83

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##### Re: testing general relativity
« Reply #4 on: 06/12/2013 12:05:37 »
i know it mite be a hard test to do, but it doent matter how long to see results .it been 50 years and we went to the moon staight away so we should off did it .any other test than a raw basic test to prove general relativity as ow source off gravity ,doent proves it,but proves general relativity to be a accurate measurement of gravity and spacetime but not the source of gravity ...coz right now thats all it can be because all the errors (like us seeing weight to gravity ratio not matching in some place in space)  and the fact quantum mechanics and general relativity just dont work together like they should. it show this test should of been done first and wait 10 years or should be done now......i have a error of my own ,i dont know if someone else has seen this but still .... if mass = gravity coz of the weight .then why is it that after billions of years the energy that a sun would use hasnt made suns mass smaller and weight less witch because of using it self as a fuel ..now that would mean less mass = less gravity ,but we see it work in reverse and get stronger with nothing fueling it .and to refuel it we would see huge amounts of energy going back in and free energy dont happen
« Last Edit: 06/12/2013 12:07:09 by Missynmax83 »

#### RD

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##### Re: testing general relativity
« Reply #5 on: 06/12/2013 13:03:47 »
... why is it that after billions of years the energy that a sun would use hasnt made suns mass smaller ...

It has lost mass via radiation, but only a tiny fraction ...

Quote from: astronomycafe.net
... over the entire life of the Sun to date [loss of mass] is about 3.1 x 10^29 grams.
The mass of the Sun is 4 x 10^33 grams so this loss equals 0.008 percent of its current mass.

#### Missynmax83

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##### Re: testing general relativity
« Reply #6 on: 06/12/2013 13:24:06 »
Is that just ow sun or a sun after going thought the path to the point of turning onto a black hole

#### RD

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##### Re: testing general relativity
« Reply #7 on: 06/12/2013 13:37:03 »
Our sun isn't massive enough to form a black hole ...

Quote from: wikipedia.org/Main_sequence
...The behavior of a star now depends on its mass, with stars below 0.23 solar masses becoming white dwarfs directly, while stars with up to ten solar masses pass through a red giant stage. More massive stars can explode as a supernova, or collapse directly into a black hole.
https://en.wikipedia.org/wiki/Main_sequence

#### Missynmax83

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##### Re: testing general relativity
« Reply #8 on: 06/12/2013 13:57:33 »
Ok .with what we do know about physics here on earth how much fuel should ow sun used in its life time

#### RD

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##### Re: testing general relativity
« Reply #9 on: 06/12/2013 14:18:00 »
Ok .with what we do know about physics here on earth how much fuel should ow sun used in its life time

#### Missynmax83

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##### Re: testing general relativity
« Reply #10 on: 06/12/2013 14:38:36 »
Do we know what the rate of compression rate of the sun shrinking over its life time
« Last Edit: 07/12/2013 00:11:58 by Missynmax83 »

#### Missynmax83

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##### Re: testing general relativity
« Reply #11 on: 06/12/2013 16:06:48 »
Isn't there a black hole (ULX-1) not doing what Einstein theory says it should not be doing
« Last Edit: 08/12/2013 03:04:44 by Missynmax83 »

#### Missynmax83

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• 103
##### Re: Has general relativity been put to the test?
« Reply #12 on: 07/12/2013 02:57:22 »
RD .... i did find this (0.0316%) as the answer for how much the sun has uses going by how much it burns to size,over years.and not by viewing the sun over time .just by maths..................The sun presently weighs about 2*10^30 kg

4 million tonnes of mass every second for 5 billion years adds up to about 6.32*10^26 kg That adds up to a grand total of 0.0316% of its present mass. So yes, it does get smaller, but by a tiny imperceptible fraction.

As it happens, there are two main ways this is lost- one is mass lost to nuclear fusion in the core, as you thought. The other is mass ejected out the surface through solar wind. ....................................                                                                                                                                                                                                                                                                                 ,.i also saw that ow sun has explanded 10% over its life coz of helium ash, wouldnt that apply to all sun and black hole to make it gravity weaken ,to dont allow a size to weight ratio that would allow a mass to colaps on it self ,because the curving of spacetime would never bend anuf for compresion of matter be stronger that the energy matter realises...i know ow sun wont turn in to a black hole ...but the finding of ULX-1 show mistake with general relativity and what happpening around the event horizon
« Last Edit: 08/12/2013 03:08:47 by Missynmax83 »

#### Missynmax83

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##### Re: Has general relativity been put to the test?
« Reply #13 on: 07/12/2013 03:33:29 »
i dont think i need to say how general relativity curving of space cant have any errors around the event horizon coz that would start to not match newton laws of gravity ....also there cant be any errors with these theory coz its only what we r that has affect on gravity ,not what the mechanics r doing....meaning if u have 2 masses that r the same ,gravity with act the same on both masses.....so for ULX-1 to not be doing what it should be just by its weight, show that it must be want its mechanics r doing.then curving space and mass theorys cant be right coz both them theorys dont affect gravity because of the mechanics,but just by its weight.....(ULX-1 has gone past its limits butt still eating and that)
« Last Edit: 07/12/2013 10:05:03 by Missynmax83 »