How Long Would Earth React to the Sun's Instant Disappearance?

[SpY]]

If then Sun had to instantaneously vanish (it's energy, light, mass) how long would it take for Earth to feel the gravitational effect (ie. change orbit) and how exactly would the orbit change?

SR limits speeds to that of light. Sunlight takes about 8 minutes to reach Earth, but is that how long gravity takes? I read a bit on the previous threads on the topic, but the last one was locked and I am still interested if anyone can explain.

Is there anyway to sort of predict how orbits in the solar system would change?

 

[FtlIsAwesome]

Gravity travels at the same speed light does, c.

Now, the predicted graviton is believed to be massless, and if it traveled slower than c would imply that it has mass, but from my knowledge the mainstream opinion is that the currently undetected graviton is massless and travels at lightspeed.

 

[pallidin]

Gravity travels at the same speed light does, c.

Sorry, though widely accepted in theory, to blatantly state that gravity expresses itself at c has absolutely NO current experimental standing/evidence.
Just to say for all those wondering...

 

[Nabeshin]

Sorry, though widely accepted in theory, to blatantly state that gravity expresses itself at c has absolutely NO current experimental standing/evidence.
Just to say for all those wondering...

I understand your caution, but your statement is too strong as well. The binary pulsars PSR 1913+16, for example, allow us to put the speed of gravity to within 1% of c.

Wiki for more: http://en.wikipedia.org/wiki/Speed_of_gravity#Possible_experimental_measurements

 

[pallidin]

It is my understanding that the "speed" of gravity has not been determined.
Do you suggest otherwise?

 

[MACHO-WIMP]

It is my understanding that the "speed" of gravity has not been determined.
Do you suggest otherwise?

According to The Elegant Universe someone mathematically, not experimentally as it should be noted, found that gravity goes the speed of light.

 

[pallidin]

binary pulsars PSR 1913+16, for example, allow us to put the speed of gravity to within 1% of c.

Wiki for more: http://en.wikipedia.org/wiki/Speed_of_gravity#Possible_experimental_measurements

That simply is not possible with regards to integrity. So far out.
I would like to see more evidence(earth-based)

 

[pallidin]

Jeeze, we were able to validate "frame-dragging" from orbital experiments.
What's the huge problem with gravity?

 

[Uglybb]

So how would you class the quasar QSO J0842+1835 result?

As I understand Asada being the only notable objection and the objection was proved to be invalid. Are there any outstanding arguments against the test?

If not the test met the standards so why doesn't the test result stand or was there a problem wiki doesn't answer that?

 

[pessimist]

While we have a least upper bound to this speed, we do not have a definite value we can identify as the speed at which gravitation propagates. Special Relativity puts this upper bound to be the speed of light. The speed of gravitation depends on which theory you use to depict it. Since we do not know for sure which theory of gravitation may be the correct one, the matter is still somewhat inconclusive.

 

[pessimist]

So how would you class the quasar QSO J0842+1835 result?

As I understand Asada being the only notable objection and the objection was proved to be invalid. Are there any outstanding arguments against the test?

If not the test met the standards so why doesn't the test result stand or was there a problem wiki doesn't answer that?

We do not conclusively know for sure that GR is the correct theory for gravitation. The result obtained from the quasar observation can yield different results pertaining to different kinds of gravitational theories. WE thus cannot conclusively state that gravitation propagates at the speed of light. But general scientific consensus is that most physicists hope that GR is true and that gravitation propagates at the speed of light.

 

[Nabeshin]

We do not conclusively know for sure that GR is the correct theory for gravitation.

I don't think the point of this thread is to determine whether or not GR is correct, so I think we should just work within the context of GR. (That said, a nice description of GWs in alternate theories of gravity is given in https://www.amazon.com/dp/0521439736/?tag=pfamazon01-20 )

 

[Vanadium 50]

That simply is not possible with regards to integrity. So far out.

Whose integrity are you

I would like to see more evidence(earth-based)

To measure the speed of gravity, you need something heavy, so you can detect it, and something fast - ideally as close to the speed of gravity as you can get it. That's not possible on earth.

 

[pallidin]

To measure the speed of gravity, you need something heavy, so you can detect it, and something fast - ideally as close to the speed of gravity as you can get it. That's not possible on earth.

OK, but wondering: What about a 2-ton mass suspended within a large earth-based vacuum chamber and the inside mass ramped-up to high frequency physical oscillations?
Is is possible to measure the perturbations of gravity in this case?
Or is the variation in gravity too weak in that circumstance?

Hope the above makes any sense.

 

[Vanadium 50]

Why don't you do the calculations so you can see for yourself what the magnitude of the effect is.