Thursday, May 5, 2011

Earth's Gravity Distorts Space and Time.

We are surrounded by swirling and distorted time and space, and no this not the effect of the Cinco de Mayo tequila... Well maybe some of it is...

Distorted space and time around Earth. (Credit: Stanford)

Yesterday NASA announced that Gravity Probe B (GP-B) confirmed two of Einstein's space-time theories. The first is the geodetic effect, or the warping of space and time around a gravitational body. The second is frame-dragging, which is the amount a spinning object pulls space and time with it as it rotates.

It is OK to be asking 'what are these theories and what probe' and 'when did this mission happen'. Honestly, it was tucked into a corner of my mind that I had entirely forgotten about until I got about half way through reading the NASA release.

I don't want to lose to many people on to many of the boring aspects of this mission, as it requires a good knowledge of physics. If you are interested in some of the deeper science behind the mission, I recommend checking out http://einstein.stanford.edu/.

The result is that we now know that there is a space-time vortex around Earth, and its shape precisely matches the predictions of Einstein's theory of gravity.

A much more detailed and science-y image. (Stanford)

Often times general relativity is thought to be one of those things where there will never be definitive proof, but this experiment changed that. One of the reviewers of the Gravity Probe B's results, Clifford Will of Washington University in St. Louis, predicts "this will be written up in textbooks as one of the classic experiments in the history of physics."

The idea behind it is that, according to Einstein's theories, time and space are woven together into a four-dimensional sheet called "space-time." The mass of objects, like the Earth, creates dimples in this fabric. Now the Earth also spins, which twists the dimple. Imagine something spinning in a jar of honey, the honey around the object gets pulled with the spin.

This is was what GP-B was created to detect. After over 40 years in development, it was launched in 2004, making this project one of the longest running in NASA's history. The idea of the experiment was simple, but a monumental task to pull off.

The basic idea is that there are 4 gyroscopes put into space. The gyroscopes have a spin axis pointed at a fixed reference point, a distant star. If free from external influence, the gyroscopes should point at the star forever. However, if space is twisted, over time they will drift off of the star. The change in direction relative to the star can be used to measure the twists of space-time.

One of the gyroscopes. (Stanford)

The epic part comes from what was done to perform this experiment. The gyroscopes are the most perfect spheres ever made by humans. At 1.5 inches across, their surfaces never vary more than 40 atomic layers.

Thirteen new technologies were invented for GP-B, including a way to measure gyroscopes without disturbing them. These new technologies have been used in various way already. This includes systems that allow airplanes to land unaided, GPS technologies, drag-free satellite concept that allows for Earth observing satellites, determining the cosmic background radiation, and magnetic field shielding.

The other cool thing is that this data proves the existence of distorted space-time. It can be duplicated when studying other celestial bodies. It has been suggested that in regions with a large and active space-time vortex, you could see a whole manner of distortions. In a system as complicated as black hole binary - one black hole orbiting another - space-time would be entirely flipped over.

Hundreds, maybe more then a thousand, people have been involved with this experiment. A lot of them are young, including high school students and undergraduates. It was a heroic feat. The probe was decommissioned in December 2010 and ceased data collection, but will have a long-term impact on physics.

Additional Reading:


38 comments:

LunaSihne said...

That title pulled me in to read. The info was interesting and confused me at times but wow.

Lost.in.Idaho said...

For those that need layman's terms...

People assume that time is a strict progression of cause to effect, but *actually* from a non-linear, non-subjective viewpoint - it's more like a big ball of wibbly wobbly... time-y wimey... stuff.

Lost.in.Idaho said...

And honestly, this is fantastic. But, when you think of faster-than-light travel, or even relativistic travel, these gravitational vortex fields are going to cause a world of problems in spaceflight.

mmmpieohyeah said...

cool, so it's no longer a theory, it's a law now!

Melanie said...

again...great post!

THUNDERCAT said...

Dayum!@LostInIdaho! You are just as smart as the Astronomy Pirate! I didnt' think ANYONE was on his level! Very impressed!

-E- said...

and yet he thought that light didn't propagate through any medium...

Moobeat said...

interesting

Zombie said...

So does this mean time travel is now possible!? :D

G said...

but what causes gravities effect...?

Megan said...

The concept of spacetime sort of blows my mind. This sounds like a pretty big achievement.
"The gyroscopes are the most perfect spheres ever made by humans." Now THAT sounds awesome.

Robert Fünf said...

Nice Dr. Who reference Lost.

Also, that's incredibly interesting. I might check out link that you gave, but I'm afraid that might actually asplod my head.

Buckaroopopcorn said...

I'm not convinced that a good mathematical model means we understand something. Math is a language. This is to say that mathematical models are about mental objects not real ones.

Just because I can define a chicken and egg with a noun doesn't mean I know how they work. Differential equations are the math equivalent of nouns. The closer we look the less they apply. A vehicle with four wheels is a car but a wheel is a tire. So just because I can say this car is travelling at n and will be in Cincinnati in T hours doesn't mean I know how cars work (or even what they are - trucks have four wheels too).

Einstein changed Newtons assumptions about absolute space for assumptions about absolute space/time and made some better maths (but not perfect by any means). I honestly don't think that means he really understands what is going on any better; he's just able to make better calculations IMO.

Anyway, good post as always, which is why I enjoy your blog!

Astronomy Pirate said...

No time travel isn't possible, not through this means anyways. Gravity is no closer to having an answer, and really neither do any of the 4 other fundamental forces. This helps aid us in our description of these forces, in order to better understand them. All these descriptions are science, which will help us build a better Universe for ourselves. We probably will never know the underlying causes of these forces, or if any human does, it will be long after we're all gone.

Schla.mp3 said...

that is very interesting

Kamchatka said...

Very interesting article. It is just fascinating to imagine that our Earth has that effect on space-time. It also amazes me how smart some individuals are...

JaksonHunt said...

woah..

JayPower said...

Wow this is amazing, never knew this ;D

The Angry Lurker said...

News to me but damn good information, made me think that Sheldon from The Big Bang Theory was involved.

mindph said...

I read once that they are planning (or doing already) to find and display gravitonal waves send by heavy spinning objects like neutron stars and black holes due to their wirlpooling the roomtime. If they get that, they could create a "graviton telescope" imaging the gavitonal surface of our universe... Amazing!

Dejch said...

looks like the Einstein's work will not be forgoten any time soon.. enjoyed reading that and learned something new..

also great blog.. following

BigMike said...

Proof of the space time relation is the first step to being able to control our place in it... Hellooooo faster then light speed travel!!

meandmythinkingcap said...

so, inception movie time equation is rite all along

Dootzkie said...

Amazing stuff right there! Knew a bit, but this expanded my views

Banacek said...

I don't believe in external linear time or the concept of space. So there.

VenomForMasses said...

Gravity is heavy stuff, man :) Great article, pro stuff..thx!

Solsby Kid said...

Wow, great info! Never knew the earths gravity could distort space and time

ScottD said...

interdesting !

pixel said...

maybe outside of our gravity is what is distorted, and we are the normal

Salman Ashraf said...

General relativity rules!

Definitely an interesting read. Thanks for sharing!

Keep 'em coming as always :)

Teen Book Reviewer said...

man that's heavy. I love reading about all this phsyics bio combination stuff. Nice, following!

Venus said...

maybe time travel would be easier is a time machine was taken to that vortex in outer space where space and time are being bended constantly.

bruno said...

Another point for Einstein

M Pax said...

Wow, that's really fascinating. You wrote a great article.

ThirteenCats said...

that's really interesting, good stuff. I once saw the space-time distortion by planetary bodies illustrated by putting a heavy ball on a stretched cloth.
+following

Kicking Rocks said...

cant wait till they prove the big bang was real...yet i think it wasn't and we were always here.

HiFi said...

Hmm I don't know. The experiment is still largely based on theories, and the parameters they've set to get definitive proof is unachievable. It's almost like saying this can't happen because this other thing isn't possible. But all is not lost. More research could lead to other discoveries. That's how science works.

MassiveUps said...

This blew my mind when I first read it, because all I could think of was Superman flying around the earth. He WAS right!!!

Post a Comment

Comments are moderated, please no advertising or profanity. This also helps me see who is dropping by.