Posted on 04/25/2013 1:10:04 PM PDT by SeekAndFind
Scientists have subjected Albert Einstein's famous theory of gravity to its toughest real-world test so far—and it has prevailed.
Einstein's general theory of relativity states that objects with mass cause a curvature in space-time, which we perceive as gravity. Space-time, according to Einstein's theories of relativity, is a four-dimensional fabric woven together by space and time.
For example, a bowling ball causes a dent in a mattress, and that dent changes the otherwise straight motion of a nearby marble on the same mattress. Similarly, the mass of the sun distorts the space-time around it. A body with less mass, like the earth, travels along one path in that distorted space, which we call its orbit.
Scientists aren't testing the general theory because they think it is wrong but rather because they are certain it can't be the final explanation—just as Isaac Newton's notion of gravitational force was superseded by Einstein's explanation.
Einstein's theory of gravity, published nearly a century ago, has passed every test it has been subjected to. Nonetheless, scientists have been trying to pin down precisely at what point Einstein's theory of gravity breaks down, and where an alternative explanation will have to be devised. Einstein's framework for his theory of gravity, for example, is incompatible with quantum theory, which explains how nature works at an atomic and subatomic level.
Consider that for a black hole, Einstein's theory "predicts infinitely strong gravitational fields and density. That's nonsensical," said Paulo Freire, an astrophysicist at the Max Planck Institute for Radioastronomy in Germany and co-author of the study, which appears in the journal Science.
(Excerpt) Read more at online.wsj.com ...
But Captain! I canna change the laws of physics.
I once heard that the eyes actually take in everything upside-down and the brain automatically turns it “rightside-up”. (shrug) Anyway, that got me to thinking that maybe the entire universe is actually inside-out and our bodies convert it to outside-in the same way. That would explain why everything on earth isn’t tossed off into space by the spinning earth’s centrifugal force. That is, the spinning earth’s centrifugal force is what holds us down.
Or, maybe it’s just becaue of this mysterious “gravity” myth... (chuckle) Yeah right.
I'd be curious to hear how many light years of bad luck it would be to break a mirror at a time like that.
As far as I know, pretty much everything Einstein ever said about gravity was wrong.
For starters Einstein claimed that information could not be transmitted faster than C. Nonetheless it is well known that gravity propagages instantaneously to within our ability to measure. Any time you ever take one step you are sending a gravitational message of sorts out into the cosmos at infinite speed.
Einstein described gravity as a sort of a four-dimensional differential geometry thing. There is no way to start with that and believe that gravity near our own Earth's surface could ever have changed much within recent geological time. Nonetheless it is an easy demonstration that it has i.e. that the largest dinosaurs would not even be able to stand in our present gravity due to the familiar and simple square/cube problem which prevents 200-lb athletes from competing in gymnastics.
There is also no way to start with Einstein's description of gravity and believe that humans would ever be able to control it, but the Podkletnov experiment is sufficiently real and advanced technological nations all have black projects dealing with gravity control.
So when we send messages to our satellites far out in solar system there is no delay between the time it was sent and received?
Here's another. Michael Moore is already dead. It's just that his mass is so great that he's warped space-time around him to such an extent that we perceive him at an earlier time when he still lived.
In any event, I tend to be philosophical when it comes to mysteries of the cosmos and physics in general. Living beings are perception processors - - and such concepts as 'space', 'time', 'existence', 'life', 'gravity', and well, ...'concept', are simply notions that have evolved and been collectively agreed upon by our species - - and shared to some extent with and among every other living earthly species - - over the course of eons.
So keep looking out into forever for the answers if you wish. It's fun to do, and I have a great deal of respect for the hobby. Estimates of "the size of the universe" (LOL!) will continue to grow every few months or so, and "unexplained mysteries" will pile up, so the hobbyists will always have plenty to keep them busy. As for me, I prefer to look for my answers right here inside my being. First I'd like to figure out to what extent the development of the humans "senses" (touch, sight, hearing, and smell) were a response to habitat (earth) and conversely, to what extent habitat is the result of human senses. (I know - - good luck with that.)
By the way, it will be interesting to see "how big the universe is" once that Hubble replacement gets up there and starts looking into the distance.
>> A good case has been made for the theory that gavity pushes rather than pulls.
Said the antagonist.
>> As far as I know, pretty much everything Einstein ever said about gravity was wrong.
Is there a limit to “pretty much everything ever said”?
bump
Or, it could be for the same reason ancient people were said to live 200+ years - - the earth was spinning faster back then.
And during the time of the dinosaurs, probably much faster.
>> A good case has been made for the theory that gavity pushes rather than pulls.
Said the antagonist.
I didn’t mean to be antagonistic. I was just mentioning that there is some fairly new controversy on the subject.
Think of my remark as a casual mention in a thread praising the movie “An Inconvenient Truth” that the earth may not be warming.
I remember that Ptolemy’s explanation of how our solar system functions actually worked - up to a point. Eventually it was scrapped of course.
Incorrect
1. Wikipedia is a valuable resource for any sort of topic for which no controversy could plausibly exist. For anything else (such as this topic), Wikipedia is worthless.
2. If there actually is such a thing as a "gravity wave", it will propagate at C as wiki claims. That's a big "IF" however; nobody has ever seen a gravity wave.
3. Gravity itself, however, propagates instantaneously as I noted. This has been known for centuries and our own solar system would not hold together otherwise.
Tom Van Flandern's page on gravity speed experiments:
http://metaresearch.org/cosmology/speed_of_gravity.asp
I don’t believe that is correct. He said MASS could not be accelerated to a speed faster than C. As far as I know he said nothing about masless information.
Face on Mars. Richard c. Hoagland. Coast to Coast AM. Oh, yeah!
“Van Flandern was a prominent advocate of the belief that certain geological features seen on Mars, especially the “face at Cydonia”, are not of natural origin, but were produced by intelligent extra-terrestrial life, probably the inhabitants of a major planet once located where the asteroid belt presently exists, and which Van Flandern believed had exploded 3.2 million years ago.[34] He gave lectures on the subject,[35] and at the conclusion of the lectures he described his overall conception:[citation needed]
“We’ve shown conclusively that at least some of the artifacts on the surface of Mars were artificially produced, and the evidence indicates they were produced approximately 3.2 million years ago, which is when Planet V exploded. Mars was a moon of Planet V, and we speculate that the Builders created the artificial structures as theme parks and advertisements to catch the attention of space tourists from Planet V (much as we may do on our own Moon some day, when lunar tourism becomes prevalent), or perhaps they are museums of some kind. Remember that the Face at Cydonia was located on the original equator of Mars. The Builder’s civilization ended 3.2 million years ago. The evidence suggests that the explosion was anticipated, so the Builders may have departed their world, and it produced a massive flood, because Planet V was a water world. It is a coincidence that the face on Mars is hominid, like ours, and the earliest fossil record on Earth of hominids is the “Lucy” fossil from 3.2 million years ago. There have been some claims of earlier hominid fossils, but Lucy is the earliest that is definite. So I leave you with the thought that there may be a grain of truth in The War of the Worlds, with the twist that WE are the Martians.
When it was first imaged, and into the 21st century, the “Face” is near universally accepted to be an optical illusion, an example of pareidolia, and theories that it was an artificial artifact were considered to be pseudo-science.[36][37] After analysis of the higher resolution Mars Global Surveyor data NASA stated that “a detailed analysis of multiple images of this feature reveals a natural looking Martian hill whose illusory face-like appearance depends on the viewing angle and angle of illumination”.
...Violates causality.
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