News Probe confirms Einstein effects

[dbeachy1]

No, not The Probe , it's Nasa's Gravity Probe B:

Nasa's Gravity Probe B has produced remarkable new confirmation of some key predictions of Albert Einstein.

The satellite's observations show the massive body of the Earth is very subtly warping space and time, and even dragging it around with it.

Scientists were able to see these effects by studying the behaviour of four perfectly engineered spinning balls carried inside the probe.

The full article is here.

 

[statickid]

how can anything be PERFECTLY engineered??? LOL



j/k thanks for the post

 

[garyw]

NASA have discussed the story here.

As for perfect I'll let this snippet explain that:

The four gyroscopes in GP-B are the most perfect spheres ever made by humans. These ping pong-sized balls of fused quartz and silicon are 1.5 inches across and never vary from a perfect sphere by more than 40 atomic layers. If the gyroscopes weren't so spherical, their spin axes would wobble even without the effects of relativity.

 

[SiberianTiger]

What does it mean, 'dragging around space-time' with it?

 

[Urwumpe]

garyw: That is obsolete data - the silicon sphere produced for the Avogadro project is much more precise, but not used in a flight instrument (instead it is used for defining what a kg actually is, because the old platinum weight isn't really accurate anymore)

The project is mentioned there: [ame="http://en.wikipedia.org/wiki/Avogadro_constant"]Avogadro constant - Wikipedia, the free encyclopedia[/ame]

To put the numbers in relation: The 0.3 nm accuracy of the Avogadro spheres is 14.667 times less than the 40 Si atom radi or about one half of a Silicon crystal lattice, depending which dimension the article talks about, of the Gravity Probe sphere. Practically speaking, the Avogadro sphere only has maximal one layer of Si atoms variation.

 

[garyw]

As I understand it, The Earth makes something of a 'dent' in the space time fabric due to it's mass but the earth also rotates so that causes the dent in the space time fabric to twist as well.

---------- Post added at 23:32 ---------- Previous post was at 23:31 ----------

garyw: That is obsolete data - the silicone sphere produced for the Avogadro project is much more precise, but not used in a flight instrument (instead it is used for defining what a kg actually is, because the old platinum weight isn't really accurate anymore)

I can only go by NASA's own press release which is dated today and they say they are the most perfect speheres every created so I'll leave the Avogadro project to challenge NASA. :thumbup:

 

[Fizyk]

What does it mean, 'dragging around space-time' with it?

It's an effect caused by rotation of a body. A rotating body distorts space-time a bit differently than a non-rotating one. It looks a bit as if the space-time was dragged by the rotating body, hence the name.

http://en.wikipedia.org/wiki/Frame-dragging

 

[Urwumpe]

I can only go by NASA's own press release which is dated today and they say they are the most perfect speheres every created so I'll leave the Avogadro project to challenge NASA. :thumbup:

Pah, I'll sue them. Maybe I'll get enough money from them for the injury for starting my own moon program.

 

[Eli13]

That would be something to see

 

[Quick_Nick]

The title made me giggle just a bit. Good to see science getting done, but how much doubt was there about "Einstein effects"?

 

[garyw]

The title made me giggle just a bit. Good to see science getting done, but how much doubt was there about "Einstein effects"?

Next to none as it's proven correct time and again but the problem with science is that you can never fully prove a theory - only disprove it so they keep testing it yet Einstein always appears to be right. Quite a feat for someone who worked a lot of this out almost 100 years ago. I wonder what he would discover if he had access todays equipment - without todays politics! :lol:

 

[RichWall]

And so it appears that "time space" is like soup.

 

[Keatah]

As I understand it, The Earth makes something of a 'dent' in the space time fabric due to it's mass but the earth also rotates so that causes the dent in the space time fabric to twist as well.

As space-time and gets dragged around, that dragged space-time also pulls on whatever "object" is in the area too. That's the reason for the ultra-precise spheres. Which, btw, are not perfect, nor does the text say they are perfect. They are the closest to being perfect as we've ever come! Most is the keyword here..

read - "The four gyroscopes in GP-B are the most perfect spheres ever made by humans. These ping pong-sized balls of fused quartz and silicon are 1.5 inches across and never vary from a perfect sphere by more than 40 atomic layers. If the gyroscopes weren't so spherical, their spin axes would wobble even without the effects of relativity."

 

[Fizyk]

Next to none as it's proven correct time and again but the problem with science is that you can never fully prove a theory - only disprove it so they keep testing it yet Einstein always appears to be right. Quite a feat for someone who worked a lot of this out almost 100 years ago. I wonder what he would discover if he had access todays equipment - without todays politics! :lol:

Actually, most of relativistic effects weren't predicted by Einstein, but by others, who found solutions to Einstein's equations. In fact, I don't recall any effects of general relativity predicted by Einstein himself other than the expansion of the universe (which, btw, he rejected at first). I usually don't pay much attention to who predicted an effect first, though

Also, I think Quick_Nick meant that those effects are better called "relativistic effects", not "Einstein effects", as Einstein didn't cause them

EDIT: On the second thought, he must have predicted something for his theory to be confirmed, like the bending of light, but I have no idea how would he do that without the Schwarzschild metric, or did Schwarzschild calculate his solution before GR was confirmed? I don't know what the sequence of events was.

 

[NukeET]

Hail Probe!

 

[RisingFury]

Don't kid yourselves, this is old news. The Gravity Probe B mission is long over, the reason the final release of data is being down now is because there was a wobble in one of the gyros causing an unexpected signal. The data analysis team continued to work in hopes of modelling where the signal came from. According to the article, the frame dragging was measured to within 20%, but for about a year now, Wiki claimed an accuracy of 16%, so my guess is they did not make any more progress...

 

[Tschachim]

EDIT: On the second thought, he must have predicted something for his theory to be confirmed, like the bending of light, but I have no idea how would he do that without the Schwarzschild metric, or did Schwarzschild calculate his solution before GR was confirmed? I don't know what the sequence of events was.

http://en.wikipedia.org/wiki/Perihelion_precession_of_Mercury#Perihelion_precession_of_Mercury