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Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 1:33 pm
by The Code
No feeling, just the urge to be one again.

Mark

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 2:03 pm
by aristarchusinexile
bystander wrote:If I carefully place a pebble in the air, why does it fall to the floor? :? Jim tells me it feels no gravity, so the law of inertia tells me it should remain where I placed it. But every time, it falls to the floor. :( What's going on?
Try lighter pebbles that don't go Bam Bam when they hit the floor. http://en.wikipedia.org/wiki/Pebbles_Flintstone

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 2:09 pm
by aristarchusinexile
JimJast wrote:
aristarchusinexile wrote: With, however, non-locality proven and saying Relativity is wrong.
And who might have done that? A quote please ...
"In physics, nonlocality is a direct influence of one object on another distant object, in violation of the principle of locality. In classical physics, nonlocality in the form of action at a distance appeared in corpusculas theories and later disappeared in field theories. Action at a distance is incompatible with relativity. In quantum physics nonlocality re-appeared in the form of entanglement. Physical reality of entanglement has been demonstrated experimentally[1] together with the absence of local hidden variables. Entanglement is compatible with relativity; however, it prompts some of the more philosophically oriented discussions concerning quantum theory. More general nonlocality beyond quantum entanglement, but still compatible with relativity, is an active field of theoretical investigation but has yet to be observed."

http://en.wikipedia.org/wiki/Non_Locality

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 2:18 pm
by BMAONE23
bystander wrote:If I carefully place a pebble in the air, why does it fall to the floor? :? Jim tells me it feels no gravity, so the law of inertia tells me it should remain where I placed it. But every time, it falls to the floor. :( What's going on?
It's obvious. The stone has no "feelings" so it cannot "Feel" gravity but it can still be affected by it :wink:

Re: Impact of intergalactic dust with type Ia Supernova

Posted: Tue May 26, 2009 2:19 pm
by aristarchusinexile
Chris Peterson wrote: "...in all too many cases, the "research" they are "on top of" is pseudoscience or just general nonsense."


You have no idea what your government's research facilities are up to, Chris.
Chris wrote:I know of no area of science where any of those regions are advanced beyond American or European work.
How about the most obvious, the military sciences. According to all that is known the Europeans and Russians are far more highly advanced than the U.S. (the 600 mph Russian torpedo is only the tip of the iceberg) with the Russian warheads which detect and avoid anti-warhead missiles the tip of another iceberg. The Eurofighter is far ahead of U.S. jets. The new Airbus leaves U.S. commercial traffic far behind. Even a poor old Canadian developed the Blackberry.

Re: Intelligent Falling?

Posted: Tue May 26, 2009 2:24 pm
by aristarchusinexile
harry wrote:
Hey! Most of the world is religious.
Watch out for winged women.

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 2:26 pm
by aristarchusinexile
BMAONE23 wrote:
bystander wrote:If I carefully place a pebble in the air, why does it fall to the floor? :? Jim tells me it feels no gravity, so the law of inertia tells me it should remain where I placed it. But every time, it falls to the floor. :( What's going on?
It's obvious. The stone has no "feelings" so it cannot "Feel" gravity but it can still be affected by it :wink:
Define 'feeling'.

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 2:28 pm
by BMAONE23
aristarchusinexile wrote:
BMAONE23 wrote:
bystander wrote:If I carefully place a pebble in the air, why does it fall to the floor? :? Jim tells me it feels no gravity, so the law of inertia tells me it should remain where I placed it. But every time, it falls to the floor. :( What's going on?
It's obvious. The stone has no "feelings" so it cannot "Feel" gravity but it can still be affected by it :wink:
Define 'feeling'.
A sence of self,
A central nervous system...

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 2:37 pm
by aristarchusinexile
BMAONE23 wrote:
A sence of self,
A central nervous system...
Electrical connections in atomic structure?

Re: Impact of intergalactic dust with type Ia Supernova

Posted: Tue May 26, 2009 2:38 pm
by Chris Peterson
aristarchusinexile wrote:
Chris wrote:I know of no area of science where any of those regions are advanced beyond American or European work.
How about the most obvious, the military sciences. According to all that is known the Europeans and Russians are far more highly advanced than the U.S. (the 600 mph Russian torpedo is only the tip of the iceberg) with the Russian warheads which detect and avoid anti-warhead missiles the tip of another iceberg. The Eurofighter is far ahead of U.S. jets. The new Airbus leaves U.S. commercial traffic far behind. Even a poor old Canadian developed the Blackberry.
I don't know what "military sciences" means. What you are describing sounds to me like engineering, not science in any fundamental sense (and even those examples are arguable). But I wasn't comparing the quality of Russian or Asian science to U.S. science, but to American and European science. Last I checked, Canada is in America, and the Eurojet and Airbus are both associated with Europe.

Re: MOG

Posted: Tue May 26, 2009 2:42 pm
by aristarchusinexile
Bubble Expansion Anti-Gravity Lightly Entitled

BEAGLE - anti-gravity bubbles (voids) growing, and causing the expansion of the universe created through (Pascual Jordan's revelation of) quantum-fluctuations in nothing. Additional bubbles in line of sight creating the increasing rate of expansion. Nor Dark Energy or Dark Matter or Singularities needed. My little puppy.

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 4:47 pm
by JimJast
bystander wrote: If I carefully place a pebble in the air, why does it fall to the floor? Jim tells me it feels no gravity, so the law of inertia tells me it should remain where I placed it. But every time, it falls to the floor. What's going on?
That's a question that Einstein had to answer too.

It turned out that if spacetime were Euclidean (as Newton thought that it was, i.e. the rate of time didn't change from place to place and the space was Euclidean) his law of inertia would work this way that a stone placed anywhere would stay there. There would be no gravitation. BTW, it happens in a free falling elevator since the spacetime in a free falling elevator happens to be Euclidean. If one is in such unfortunate circumstances (of Euclidean spacetime) one may notice that a stone placed anywhere stays there. It won't last long though. And it doesn't happen if the elevator stays on the Earth.

On the Eearth stones and apples keep falling regardless how carefully we place them in the air. They are not paying any attention to Newton's law of inertia. So Newton had to add to this picture a "gravitational attractive force" that he had to imagine as pulling things towards the Earth. Newton didn't like this "force" since it whould have to act at a distance through empty space, which Newton believed is impossible. So he never agreed to admit that such a force exists in nature and he thought that his laws are only the math but the "physics of gravitation" is different. He was right.

Einstein solved the Newton's dilema by assuming that instead of "attractive gravitational force" acting at a distance the time runs at different rate in different places and the space is curved. This assumption turned out to be enough to change Newtons law of inertia in such way that when one leaves the stones or apples alone they start moving with a speed that is limited only by their inertia and curvatures of the spacetime. The "gravitational force" is not needed to explain the movemerts of those objects. So the Newton's law of inertia is valid again but only within space of free falling elevators, which then got named "inertial systems" (or "inertial coordinate frames").

It explained also another mystery, namelly why all object fall with the same acceleration as if "attractive gravitational force" acting on each object separately was adjusted for each object to its ineria. It turns out that within an inertial system the objects don't fall at all. They just stay put wherever they were put. So nothing depends on their inertia. It may be a feather or a piece of gold and both stay where they are, not changing their position in relation to each other as Newton's law of inertia tell them to do. This way Einstein eliminated "attractive gravitational force" from physics, introducing in its place curvatures of spacetime and not changing the Newton's law of inertia still working the same in Euclidean spacetime.

People refused to believe that the solution to Newton's problem of a force acting at a distance through empty space is such simple so they did several tests with precise clocks. It turned out that the time really runs slower closer to the Earth just by the amount that Einstein's theory predicted.

That's why physicists accepted Einstein's idea that "attractive gravitational force" acting at a distance doesn't exist. Now they believe that so called "gravitational force" is inertial force acting against any attempt to force the object out of its prefered positions of rest within an inertial system defined by the curvatures of spacetime (the time dilation and the curvature of space).

Re: Intelligent Falling?

Posted: Tue May 26, 2009 5:08 pm
by BMAONE23
aristarchusinexile wrote:
harry wrote:
Hey! Most of the world is religious.
Watch out for winged women.

don't let Lillith hear you say that

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 5:58 pm
by JimJast
aristarchusinexile wrote: With, however, non-locality proven and saying Relativity is wrong.
http://en.wikipedia.org/wiki/Non_Locality
Sorry ari but I don't see why this article tells you eiter that non locality is proven or that relativity is wrong. You should explain why you have such an impression with your own words so I can ask about all the words that I don't undertand and you can explain it since they will be your own words, not just wikipedia's. Kind of I'm responding to those who don't understand why free falling stones don't feel gravitational force. But maybe we shouldn't discuss it in this forum since the subject of non lcality does not have much to do with anything related to astronmy and since I believe that physics is always local and relativity is right it might be a very long discussion. :(

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 7:28 pm
by rstevenson
JimJast wrote:Einstein solved the Newton's dilema by assuming that instead of "attractive gravitational force" acting at a distance the time runs at different rate in different places and the space is curved. This assumption turned out to be enough to change Newtons law of inertia in such way that when one leaves the stones or apples alone they start moving with a speed that is limited only by their inertia and curvatures of the spacetime. ...
Hi again Jim,

I'm beginning to understand -- or maybe not. :?

In the above quote you say, "... when one leaves the stones or apples alone they start moving ..."

Is it the mass of the earth that has deformed space/time locally and the stone is simply moving towards that center of mass? Not being pulled (as in gravity) and not really being pushed either -- just trying to come to rest in the most stable position around, the center of mass of the earth/moon system, or as close to it as the stone can get?

Rob

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 7:40 pm
by aristarchusinexile
JimJast wrote:
aristarchusinexile wrote: With, however, non-locality proven and saying Relativity is wrong.
http://en.wikipedia.org/wiki/Non_Locality
Sorry ari but I don't see why this article tells you eiter that non locality is proven or that relativity is wrong. You should explain why you have such an impression with your own words so I can ask about all the words that I don't undertand and you can explain it since they will be your own words, not just wikipedia's. Kind of I'm responding to those who don't understand why free falling stones don't feel gravitational force. But maybe we shouldn't discuss it in this forum since the subject of non lcality does not have much to do with anything related to astronmy and since I believe that physics is always local and relativity is right it might be a very long discussion. :(
Jim, the article states:

"In physics, nonlocality is a direct influence of one object on another distant object, in violation of the principle of locality. In classical physics, nonlocality in the form of action at a distance appeared in corpusculas theories and later disappeared in field theories. Action at a distance is incompatible with relativity. In quantum physics nonlocality re-appeared in the form of entanglement. Physical reality of entanglement has been demonstrated experimentally[1] together with the absence of local hidden variables. Entanglement is compatible with relativity; however, it prompts some of the more philosophically oriented discussions concerning quantum theory. More general nonlocality beyond quantum entanglement, but still compatible with relativity, is an active field of theoretical investigation but has yet to be observed."

In my own words:

Non locality is action (perhaps more accurately reaction) at a distance, action unaffected by physical or electrical intervention. This is demonstrated by manipulating a molecule in one lab and having a cloned molecule in another lab hundreds of miles apart react the same way the manipulated molecule is behaving. I can't do it myself of course as my kitchen is too busily used by other roomers, but I have read that it has been done more than once by reputable labs, notably in Europe. Non-locality is part of physics, and any part of physics is important to astronomy, as astronomical components are physically formed and react physically. I think it possible through non-locality that two stars on different 'sides' of the universe may be the exact same star .. and not a mirror image. Seeming mirror images of parts of the universe have not been explained. Non-locality means instant transmission of information .. instantaneous means faster than light, which, I assume, is why it is incompatible with Relativity. An example of the possibilities involved in non-locality seems to appear in the Book of Acts, in which Phillip (the Apostle, not the Prince) disappears from one place after baptizing the Ethiopian eunuch, and is found in a distant city. I dislike the word 'entanglement' as non-locality seems to be direct and precise, uncomplicated.

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 7:44 pm
by aristarchusinexile
rstevenson wrote: "-- just trying to come to rest in the most stable position around, the center of mass of the earth/moon system, or as close to it as the stone can get?

Rob
Voila - matter which is not at rest disintegrates (rock or apple lying on the earth's surface) so that its basic components can get to a state of rest, of ultimate equilibrium .. it will be a long process, but nature is patient, the whole earth, though, groaning ...

Re: Intelligent Falling?

Posted: Tue May 26, 2009 7:50 pm
by aristarchusinexile
BMAONE23 wrote:
aristarchusinexile wrote:
harry wrote:
Hey! Most of the world is religious.
Watch out for winged women.

don't let Lillith hear you say that
I've heard of her myth, but never heard her described as having wings. However .. I will perhaps speak more quietly.

Re: Impact of intergalactic dust with type Ia Supernova

Posted: Tue May 26, 2009 7:55 pm
by aristarchusinexile
Chris Peterson wrote:
aristarchusinexile wrote:
Chris wrote:I know of no area of science where any of those regions are advanced beyond American or European work.
How about the most obvious, the military sciences. According to all that is known the Europeans and Russians are far more highly advanced than the U.S. (the 600 mph Russian torpedo is only the tip of the iceberg) with the Russian warheads which detect and avoid anti-warhead missiles the tip of another iceberg. The Eurofighter is far ahead of U.S. jets. The new Airbus leaves U.S. commercial traffic far behind. Even a poor old Canadian developed the Blackberry.
I don't know what "military sciences" means. What you are describing sounds to me like engineering, not science in any fundamental sense (and even those examples are arguable). But I wasn't comparing the quality of Russian or Asian science to U.S. science, but to American and European science. Last I checked, Canada is in America, and the Eurojet and Airbus are both associated with Europe.
The topic was "Russia, Europe and South East Asia are on top of their research."

The examples are not arguable in any common sense.

Canada is in North America, 'America' is traditionally and correctly used to describe the United States, and the countries are not philosophically enough alike to be grouped together.

If engineering is not a science, then astronomy is voodoo.

Of course, I was not saying Airbus or Eurojet are Canadian even though a Canadian (chief Avro Arrow designer) designed the Concorde.

Cheers .. my computer time is up.

Re: Why free falling stones don't feel gravitational force

Posted: Tue May 26, 2009 7:59 pm
by makc
aristarchusinexile wrote:Jim, the article states:

"In physics, nonlocality is a direct influence of one object on another distant object, in violation of the principle of locality. In classical physics, nonlocality in the form of action at a distance appeared in corpusculas theories and later disappeared in field theories. Action at a distance is incompatible with relativity. In quantum physics nonlocality re-appeared in the form of entanglement. Physical reality of entanglement has been demonstrated experimentally[1] together with the absence of local hidden variables. Entanglement is compatible with relativity; however, it prompts some of the more philosophically oriented discussions concerning quantum theory. More general nonlocality beyond quantum entanglement, but still compatible with relativity, is an active field of theoretical investigation but has yet to be observed."
:roll:

Re: Impact of intergalactic dust with type Ia Supernova

Posted: Wed May 27, 2009 6:46 am
by harry
G'day from the land of ozzzzzzz

In a way Chris's attitude has proven my point.

Re: Intelligent Falling?

Posted: Wed May 27, 2009 7:11 am
by harry
G'day from ozzzzzzzz

Who is lillith?

Was, is she a babe?

Re: Intelligent Falling?

Posted: Wed May 27, 2009 7:45 am
by makc
that's mother of all daemons :) I think... and adam was the father.

Re: Intelligent Falling?

Posted: Wed May 27, 2009 8:20 am
by harry
G'day from the land of ozzzz


Wow!!!!!!!! sounds like my wife.

Re: Why free falling stones don't feel gravitational force

Posted: Wed May 27, 2009 8:35 am
by JimJast
rstevenson wrote:
JimJast wrote: Einstein solved the Newton's dilema by assuming that instead of "attractive gravitational force" acting at a distance the time runs at different rate in different places and the space is curved. This assumption turned out to be enough to change Newtons law of inertia in such way that when one leaves the stones or apples alone they start moving with a speed that is limited only by their inertia and curvatures of the spacetime. ...
Hi again Jim,

I'm beginning to understand -- or maybe not.

In the above quote you say, "... when one leaves the stones or apples alone they start moving ..."

Is it the mass of the earth that has deformed space/time locally and the stone is simply moving towards that center of mass? Not being pulled (as in gravity) and not really being pushed either -- just trying to come to rest in the most stable position around, the center of mass of the earth/moon system, or as close to it as the stone can get?
Hi Rob,

It seems that you understand it just right. :D

The important thing about it is that the stone does not need any "pulling" (nor "pushing") by any mysterious "gravitational attraction" (or "repulsion"). It is so since the time and space that cause the "movement" (from our point of view, not the stone's POV though) with which it has "direct contact" are just there where the stone is. The need for "gravitational attraction" disappeared from physics and what was left were only the curvatures of spacetime (I use plural since there is curvature in any spatial direction and "in time" too, which mathematically make so called "tensor" that has 10 independent components, mathematically a bit complex things but physics of it is simple, as you just described it).

The stone is not really "pushed" by anything but one may say that it is "pushed by it's own inertia" (especially when it hits some obstacle on its way) rather than "pulled by anything acting from outside". It would surely satisfy Newton since he hated "gravitational attraction", which is a "pulling action at a distance". He could easily agree on inertia since it is a local phenomenon (of interaction between the stone and the time and space). He just didn't know how this inertia causes the stone to drop in relation to the Earth (and Moon and the all other stuff of universe). It required Riemann who discover curved spaces, Einstein, who applied them to explain gravitation, and experimentalists who measured the time dilation and the curvature of space and found that it is real and exactly as predicted theoretically by Einstein :D

I might have add that it required little me to say how it all explains the observed illusion of accelerating expansion of universe, which is even simpler being just a piece of high school math, but I don't want to risk being banned from one more moderated forum so I skip this part.