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Reflected Gravitational Waves
WSOGMM sends in an arXiv blog post about reflecting gravity waves. The speculation is that reflected gravity could go some ways toward explaining the odd readings being returned by Gravity Probe B. "In the couple of weeks since he introduced the idea that superconducting sheets can reflect gravity waves, Raymond Chiao from the University of California, Merced, has been busy with a couple of buddies working out how big this effect is... Chiao and co. ask how big the effect of a gravitational wave on a thin superconducting sheet is compared to the effect on an ordinary conducting sheet. The answer? 42 orders of magnitude bigger."
Douglas Adams gave us that answer forever ago.
Has been brought to you by reflected gravity waves!
So when do we get the report of people seeing UFOs that loocks like a surfer dude.
Either that's a scientist's prank or Douglas Adams really was right!
Attention wannabe comedians:
There is a 42 reference in this story. This your cue...this is your chance..the spotlight is on you to bring humor to the world and make countless references to Douglas Adams. Because he mentioned the number 42 in a book!
...how many superconducting sheets do I need to make a hoverboard?
From the article:
"If there were an obvious interaction between a superconducting films and gravitational waves, wouldn't Gravity Probe B have picked them up somehow?.....As it turns out, the experiment has been throwing out anomalous results ever since it was launched......The team has puzzled over them for years now....."
I really do love those moments in science when something you have puzzled over for years may have an elegant answer after all.
Eagles may soar, but weasels don't get sucked into jet engines
is it predicted by ordinary physics? Any references?
Ok! where's my gravity boot!
dot slash dot slash dot org
Just like the concentric rotating benzels in Carl Sagans book Contact. Maybe he had a gravitational wave resonance thing happening there.
http://michaelsmith.id.au
Eugene Podkletnov has been claiming for some time to have produced gravity shielding using levitated superconducting disks. The scientific community has mostly rejected his work, although NASA was for a time attempting to reproduce it. There's an article on it from a few years back on wired:
This theory has implications that could revolutionize scientific thought across numerous fields. It may even provide some direction for the unified theory people to look in that isn't horribly complex and require inventing 1700 dimensions to make the math work.
Also if people don't understand how large 42 orders of magnitude really is 10 is one order of magnitude. 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000 is 42 orders of magnitude... Granted the numbers they are dealing with are very very small to start with and even 42 magnitudes larger is still pretty damn small this change in scale is mind boggling and shows much more we have to learn about the universe in general and the properties of superconductors in particular.
-Lify
I'll meet you at the intersection of "Should be" and "Reality"
Doesn't this discovery also lead to the possibility of building super-sensitive gravitational wave detectors that really work....... Remember this - If you can't measure a phenomena, you have little hope of truly understanding it.
Martin Tajmar also posits an a-posteriori explanation for the anomalous data from Gravity Probe B based upon Cooper-pair mass in Niobium superconductors in: arxiv.org/abs/0707.3806
Heim Theory predicted such effects in 1950s already. Droscher & Hauser have suggested mechanism based on Heim Theory which was a-priori prediction as commented in the cover story of New Scientist Jan 2006, 3 months before Tajmar's announcement on the ESA homepage.
Here is the latest paper from Droscher & Hauser which gives explanation for outcome of both Tajmar and GP-B experiments.
Personally I like this part:
Numerous experiments by Tajmar et al. were carried out since 2003, and first published in 2006 report on the generation of gravitomagnetic (spacetime twisting) and gravity-like fields (acceleration) in the laboratory. The gravitational effects measured were about 18-20 orders of magnitude larger than predicted by the Lense-Thirring effect of GR. In other words, the rotating niobium ring, having a mass of some 100 grams as utilized by Tajmar et al., produces a gravitational effect similar to the mass of a a white dwarf.
/Joss
I want my hover car now. Assuming perfect reflection it shouldn't be a problem right???
Unless the flaming summary is wrong (who RsTFA?).
Though I wonder if anything on the Pioneer spacecraft is now at a temperature that's superconducting?
If you can reflect it, you can make a curved "mirror" to concentrate it to a single point in space.
If you can concentrate it, you can amplify it.
And if you can amplify it, then maybe you could directly measure its effects (something that has not been done yet)
And once you measure its effect directly, you can compare your results to the various theories (there are plenty)
If you compare results, you can refute some of the current theories, and maybe create others.
Then maybe you can use reflected and concentrated gravitational waves for long-distance communication? or for detecting matter in the farthest reaches of the galaxy...
tinfoil(){ they made the gravity probe to look for proof to some theories, the probe returned data, it did not fit with what they wanted, so the probe is wrong, broken and what not... you are doing it wrong folks } now if they can prove that using superconductors you can actually control gravity, that could be some advance in the 'nice' direction, and by control i'm not talking of going out of the earth or flying top speed nose down on one of those planes
IANAP, I am a simple Java writing hack, and I may be too stupid to understand the explanation, but I find the analogy deeply unhelpful. On the other hand, the effect of gravity waves is easily understood; if I was receiving light from an obect travelling towards me and a gravity wave front passed along the line between us, either the light frequency would rise above nominal, fall below nominal and then return to nominal, or vice versa, as our relative velocity momentarily rose, fell and returned to nominal. There is no reflection involved, merely the normal behaviour of wavefronts, though I imagine the actual phenomenon would be more complicated because, of course, a pure single cycle of a sine wave never happens.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Something which reflects gravity? That's cavorite!.
Oh yeah, snake oil. Between these "gravity waves" I've never heard about (despite college my level quantum physics classes), the nearly magical (and unexplained) use of superconductivity effect and the obvious HHGTG reference, I smell a rat.
I think this means that it might be possible to build a gravitational wave telescope. I get first dibs on a patent/prior art if the big corporations don't completely emasculate the USPTO's ability to grant patents to the little guys.
P.S. I also get first dibs on the 'gravitational wave sterling engine, powering devices on earth from colliding black holes out there!'
Didn't they make this kind of experiment in Primer? (http://en.wikipedia.org/wiki/Primer_(film)) Decreasing gravity with superconductors?
There's a couple of proofs that P=NP, gravity waves, all these holy grails are in there. I wonder if they should rename this site: "Popular Mechanics Research"
This is my sig.
Nassim Haramein provides a grand unified field theory on gravity, universal spin and the fractal nature of the universe at http://theresonanceproject.org/ This is some incredible stuff. Several of his lectures can be found on google video. The 8 hour long one is highly recommended!
Don't try to be scientifically serious with an answer that contains the number 42.
It is already known that Einstein's views on gravity are not compatible with quantum theory. Many theorists suspect that the strong equivalence principle is wrong. Thinking of gravity as a curvature of space-time itself has its days numbered.
Just look up "does uniformly accelerated charge radiate" and the Unruh effect in your favorite search engine.
Didn't know we were in april yet...
From what I've read about this, if Chiao is right we should be able to use gravity waves for communication. Since normal matter's completely transparent to gravity waves there'd be no more need for communication satellites. An antenna in the basement could reach the rest of the planet.
Disclaimer : IANAP, IAAMD. And we doctors aren't very renown for our skill in physics...
the analogy requires it to change path so as to lose potential energy and gain kinetic energy as a result of the perpendicular field. So the thought experiment seems to gravity as a deflected rubber sheet into which things fall because of another gravity in an external dimension. To make things worse, the rubber sheet is effectively 2D in a 3D universe.
Well, that's a way to interpret the rubber sheet metaphor and as you point out, it requires a sheet in a higher dimensional space and an additional perpendicular force. As it is enough to have a mental image of beads making turns on a sheet, it seem to be enough when taught in school.
From what I understand, the importance isn't the higher dimensional shape, it's the shapes of the cells on the grid that represent the rubber sheet on the illustration.
Physical bodies aren't bead rolling *on* the sheet. The sheet is the space-time itself. Physical bodies are travelling inside the sheet, crossing cells of the grid.
In the absence of that field the object would presumably travel through the space time deflection with unchanged velocity
And that's what happens. An object is simply going straight ahead, moving from one grid's cell to the next one.
But the 2D universe grid isn't regular as on a flat sheet. Big masses "wrap" the space around them and cells have strange deformed shapes.
It's just handy to paint those deformed cells as a bump.
And the object is simply following the same path as before, but as the cells it "crosses" are weirdly shaped, the point where the object leaves one cell isn't in line with the points where the object left the previous cells.
It follows a straight path, but as the terrain isn't even, the net result is a curve.
In our 3D universe, what form does the curvature take?
It's still a grid. It's now a 3D grid. Composed of small cubic cells. Except that, around big masses, the cells all of sudden aren't perfectly cubic anymore.
Thus if an object was following a subjectively straight path from on cell to the next, seen from the "outside" the path will be curved, because the cells have non-cubic shapes.
I've actually seen one exposition (for 100th anniversary of Einstein's annus mirrabilis) where it was indeed shown that way.
This model is nice because it helps understanding why massless thing such as light still recieve an effect (gravitational lensing) from big masses :
- on the high dimensional rubber sheet it won't work as they won be affected by the perpendicular "extra-gravity".
- but on the grid, they just run straight ahead in the cells and the cells happen to have been shaped into a curve. Thus "seen from far away", the resulting path is a curve. Massless light particle just happen not to make any curve around them on their own.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Maybe we can soon get sub-etha radios and communicate across the universe to hail a passing star ship?
Excuse me, but please get off my Pennisetum Clandestinum, eh!
If gravitational waves can shake a superconducting sheet, will shaking a superconductive sheet create gravitational waves? Wouldn't that open things up to some amazing experiments?
that's why. extrapolate the ability to gather and focus gravity as we do with light. Then point that concentrated gravity somewhere... uggh.
"If still these truths be held to be
Self evident."
-Edna St. Vincent Millay
Is there any reliable experimental evidence of any connection between electromagnetism and gravitation? While there are some respectable theorists like Chiao who postulate such connections I would like to know of any experimental demonstrations.
In other words, the rotating niobium ring, having a mass of some 100 grams as utilized by Tajmar et al., produces a gravitational effect similar to the mass of a a white dwarf.
Faster than light communication?
There have been rumblings about this sort of thing in various crackpot circles for years. A good reference is the following from NASA's breakthrough propulsion project:
http://www.grc.nasa.gov/WWW/bpp/overview.html
See "Podkletnov Gravity Shield"
I hope someone a lot smarter than myself starts taking this crap seriously because I want my damn hoverboard!!
Thanks for the link to the new cult :p
FTFS:
"If still these truths be held to be
Self evident."
-Edna St. Vincent Millay
Re-read the experiment.
A spinning disk did noting.
A disk that being spun up DID do something.
It was the change in acceleration of the disk that caused the sheilding.
Brrrr!
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Oh Gravity Probe B, why can't you be more like Gravity Probe A?
(Checks calendar) Dude... you're a week early!
I've abandoned my search for truth; now I'm just looking for some useful delusions.
If you have a point particle that is one planck unit in diameter and made it that much bigger (diameter), it'd be 1.6 x 10^7 meters in diameter.
The Earth is 1.2 x 10^7 meters in diameter just to give you an idea.
Volume wise I think (can't quite remember the math) it would be about 16 km in diameter.
Another way of thinking about it:
According to the general theory of relativity, gravity must warp space-time. Why?
The general theory of relativity says that time and distance with respect to a body in motion slows and becomes shorter as compared to a stationary observer.
So, for example, say I'm in a massive car tire floating in outer space.
And you're in a spaceship watching me.
Let the car tire be rotating about its axis such that it has the appearance of rolling to you in the spaceship. And let my person be standing inside the car tire.
Lastly, let there be a clock and a ruler suspended in the middle of the car tire, and let my person also have a similar clock and ruler.
Since the car tire is rotating, and I'm inside of it, I feel the force of the rubber pushing up against my feet. You, stationary in your spaceship, know that the force I feel against my feet is from centripetal acceleration. However, I in the tire don't know this. It feels more like gravity to me, and since, in relativity, every view point is valid, it is gravity.
Now, back in the spaceship, since relative to you, I'm moving, and hence my ruler and clock are as well, they will be affected by the velocity in the manner mentioned above. However, the ruler and clock in the center will not be affected since they are stationary. Hence the time and distances between the center and the perimeter will be different.
For me in the tire, I'm actually experiencing a variable gravitation field, since, if I had a ladder which went up to the center of the tire, as I climbed towards the center, the gravitation field would be diminishing. Now, if I look at the clock and ruler in the center where there's no gravity, I find that they are different from the clock and ruler on my person in the gravitational field.
Therefore: gravity affects space-time. It then follows through some fancy arguments that it actually warps space-time.
This just looks like electromagnetism near the superconducter. Particles will reflect a force weaker than it magnetic force. A superconducter induces a opposite charge on particles locally thus repelling them. No gravity involved here other than the natural pull.
I'm sure you have all see levitating objects with this principle. dIj is just your higher and higher electrical source needed.
FTFA
Chiao's claim is that gravity has a fundamentally different affect on localised particles compared to delocalised ones
So they probably mean "reflection" as in thinking? Wow!
So is it possible to construct a superconducting board that reflects gravitational waves and allows the pilot to "surf" through air and space?
I grew up in Merced a 40k population town of farmers and migrant workers (30 years ago), now our newly christened University is leading slashdot and expanding the universe. What now Bitches!
Non one else is amazed to learn that something other than mass interacts with gravity... ?
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
Huh? I guess I have to follow the literature more. I heard him very enthusiastically telling students about this idea of reflected gravitational wave from superconductor when I took his laser physics class back in UCB---before he moved to Merced---in '02.
The only possible interpretation of any research whatever in the 'social sciences' is: some do, some don't
Being derived from a person's name, the unit joule is written with a lowercase j, but the abbreviation is written with a capital J
And the square root of (-1) is j. Ask Python:
Although Python does accept a capital J as sqrt(-1). Perhaps someone should write a PEP about that.
Why is it that every time a scientific discovery is mentioned someone has to say that Tesla discovered it first?
If every invention someone attributes to Tesla really existed we would have had flying cars a hundred years ago.
Isn't gravity weaker than electromagnetism by about 41 orders of magnitude? Could there be some kind of unification going on here?
Yo dawg, I heard you like the Ackermann function, so OH GOD OH GOD OH GOD
Graphene is a much studied material these days, and it too consists of a thin film/sheet, whose carbon atoms are localized in a lattice, while its electrons appear to travel masslessly and non-geodesically. Graphene exhibits this behavior across a wide temperature range, even though it is not a superconductor. I'm wondering why graphene couldn't be used to similarly investigate the nature of gravity waves, or to create mirrors and other elements of gravity optics.
Actually quite slack jawed. This could be something that leads to a quantum theory of gravity.
Does this means that levitating cars are coming to the shops now? Where can I order mine?
...he has a razor that is very useful in these situations. You have three choices: one and two are rather bizarre theories that require significant new physics (reflecting gravitational waves or Heim theory). Choice three uses conventional physics, and is therefore boring. But it explains the GpB data so far.
Until polhode effects can be ruled out, Occam's razor pretty much requires us to stick with this explanation. Don't use a complex experiment to make claims about new physics unless you understand the experiment really, really well. It is just too easy for the "new physics" to turn out to be some subtle effect in the experimental hardware.
And you heard me loud and clear.
Choke on a goddamned cock.