Chinese scientists find evidence for speed of gravity

[fast]

The baloney you just wrote is breathtakingly idiotic!! Where did you get this nonsensical clap-trap that 'space itself can certainly expand so fast that it causes two objects inside the space to move apart faster than the speed of light'??? Have you even made the effort to read Einsteins Special Theory of Relativity? You're confusing the issue with 'relative' speed - points which moved faster than the speed of light but with respect to each other. But even here, they don't. Read on....

The speed of light is a constant relative to its source. No object can exceed the speed of light relative to its launch point.

Special Relativity also contends that velocities cannot be added together in the same way as they are in classical mechanics. For example if two objects move in opposite directions both at speed 0.8c from a common starting point, classical mechanics tells us that their velocity relative to each other should be 1.6c – 60% faster than light.

Special Relativity however uses a different formula namely:

Where v is the observed velocity and v1 and v2 are the velocities of particles 1 and 2 and are in opposite directions. Suffice to say that it comes from the time dilation and length contraction formulas, both of which come from the Lorentz Transform (LT). v1 and v2 are both 0.8c, so the observed velocity will be 0.976c, which is less than the speed of light.

The formula guarantees that v< c. Period. Any amount of your mumbo-jumbo cannot obfuscate this fact.

Read up on metric expansion of space and shut up.

 

[OrionHunter]

Read up on metric expansion of space and shut up.

I didn't know I'd be crossing swords with imbeciles like you who know squat. For you darn info, metric expansion, though modeled mathematically with the FLRW metric, is valid only on large scales, like galaxy clusters and above. At smaller scales matter has become bound together under the influence of gravitational attraction and such bound objects clumps do not expand at the metric expansion rate.

Can you try getting this into your thick head? And stop pretending that you're an expert in this topic. As they say, a little knowledge is a dangerous thing. So just shut the heck up and go read some comics instead. Leave the serious topics to the experts.

 

[xyxmt]

the source must have published something wrong..gravity is referred by acceleration which is rate of change of speed.the term "speed of gravity is absurd" may be it has to say rate of change of gravity

it is about the speed with which gravitational forces effect an object.

 

[KRAIT]

a little learning is a dangerous thing!
This gives you and other ignoranmus who has made stupid accusations an idea of what the article is about:
Speed_of_gravity
the above links by the OP are just very basic introductions. Anyone who is serious in knowing the full process of experiment and the result has to read the paper carried by the German publisher or wait until Jan 2013 release on Chinese Science Bulletin!
Great Discovery nonetheless!

Post the news when it is published. Would like to read and ask few questions to the people here who understand this phenomenon.

 

[gpit]

No Krait
Quantum theory is related to particle nature of light,

In fact Krait is partially right. There is some overlapping between the two, not quite replacing each other though.

In EM case, for instance, wave is statistical behavior of particles as described by quantum theory, when huge amount of particles appear.

 

[fast]

I didn't know I'd be crossing swords with imbeciles like you who know squat. For you darn info, metric expansion, though modeled mathematically with the FLRW metric, is valid only on large scales, like galaxy clusters and above. At smaller scales matter has become bound together under the influence of gravitational attraction and such bound objects clumps do not expand at the metric expansion rate.

Can you try getting this into your thick head? And stop pretending that you're an expert in this topic. As they say, a little knowledge is a dangerous thing. So just shut the heck up and go read some comics instead. Leave the serious topics to the experts.

So you started to backpedal on your ignorant claim after being pointed out on your mistake. Let me quote your extraordinary claim below where you exclaimed with absolute confidence that nothing in the WHOLE universe can travel FTL. I just showed you galaxies can move away in faster than the speed of light. BTW, you still got the concept of metric space expansion wrong but you are on your own.

How can anything in the universe travel FASTER than the speed of light? This is a bunch of unmitigated nonsense!

(blah blah blah, whole bunch irrelevant nonsense)

So much for the so called 'speed' of gravity!

I've never pretended I am an expert on this topic. These are basic knowledge in astrophysics, which you didn't know while claiming yourself as the expert. You didn't even know what the speed of gravity is and what the topic of the experiment is about and started to shoot off your ignorant big mouth. Yeah right, a big mouth expert in unmitigated nonsense. Stop being an ignorant cunt throwing a fit when someone teaches you something you don't know.

Another piece of advice. Stop digging. Your ignorance is showing through in every post.

 

[krash]

@fast: About the galaxies,planets, etc moving apart faster than the speed of light you said that we would stop seeing them then. Could you please explain that a little? Wouldn't we not see them if they were moving towards us faster than light?

 

[fast]

@fast: About the galaxies,planets, etc moving apart faster than the speed of light you said that we would stop seeing them then. Could you please explain that a little? Wouldn't we not see them if they were moving towards us faster than light?

There were observations and experiments that confirm the universe is expanding in an accelerating rate. Some thing or some force is pushing the universe apart in all directions. People call that dark energy since we don't know much about it. New space is literally being created between galaxies making them further apart. The rating of space expansion is increasing that make the galaxies appear to fly away from each other faster and faster, and eventually they will move away at a rate faster than speed of light.

When that happens, the light departing from the other galaxy will never reach us since the speed of light is constant at c but we are moving away at a rate faster than c. Note that this doesn't violate special relativity because special relativity doesn't deal with space expansion. Actually the space between the other galaxy and us is increasing at a rate faster than c. It's like the light is traveling in a space which becoming thicker faster than it can travel.

Luckily dark energy is pretty weak compared to local gravity so that our galaxy Milky Way and its local group can hang together resisting the expansion. One scenario of how the universe will end is that all galaxies beyond our local group will disappear and we will see much less stars from our local group. Everywhere else is dark.

On the other question, when two objects moving closer toward each other, they can't be faster than speed of light since space expansion is not in play and special relativity applies.

 

[Vitchilo]

Gravity is faster than light IMO.

If the Sun disappeared right now, the effects would be felt right away gravity wise but the light coming from the Sun would only stop about 8 minutes later.