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astroton
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by astroton » Fri Jan 13, 2006 10:37 am
Einstein corrected Newton's law of gravity, but in modern times while calculating orbits of the solar objects Newton's law is still being used.
If a gravitational object does curve space around it and an orbiting object merely sattles into this curved space, why most objects have elliptical orbits?
Should not an object such as the sun distort space around it evenly (Considering the the centre of the gravity) and if not evenly at least proportionally to it's shape?
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astroton
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by astroton » Fri Jan 13, 2006 10:49 am
Fellow astrophile sitting with me suggests so...
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harry
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by harry » Fri Jan 13, 2006 11:19 am
Space cannot be curved.
Gravity can be curved.
Matter and energy can be curved.
Harry : Smile and live another day.
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Empeda2
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by Empeda2 » Fri Jan 13, 2006 12:20 pm
Even if the sun does distort space perfectly "circular" there's no reason for planets to follow circular orbits.....
The example that is always used to simulate space-time is putting a lead sphere on a trampoline. You can then push a marble towards it and it will 'orbit' it.
If the marble comes in at a tight angle, it's paths will still be changed by the shape of the trampoline caused by the lead ball, but, depending on the marble's speed, you will see it travel in an ellipse.
Hmmm.. that's not very clear is it - but hopefully you'll get the gist of what I'm trying to say!
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Empeda
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makc
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by makc » Fri Jan 13, 2006 1:10 pm
you came to relativity from wrong end. rather than asking numerous high-level questions, why wouldn't you 1st take a look at WHAT have changed since Newton?
very basic thing is relativity of simultaneity: same things happen at the same time, or not, depending on your relative motion to these things. This is simple, direct consequence of 1) our definition of "time", and 2) lightspeed invariance postulate, you don't even need formulas to see that.
Once you got that, twins "paradox", for example, stops being paradoxical, and you have no problems understanding what does "curved space" means.
(long time ago I had these discussions somewher, and I even was going to make flash presentation on that, but I didn't... this year I've started a personal page, which is going to be something BIG in flash, and I might include it there)
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gordhaddow
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by gordhaddow » Fri Jan 13, 2006 3:38 pm
Newtonian physics is sufficient for most normal orbital calculations; even for Mercury, the total impact of General Relativity on the orbital precession is only 43 arc-seconds (43/3600 degrees) per century.
Several things have to be taken into consideration in determining what the gravitational curvature will be (keeping in mind that the 'fabric' of space is at least 3-dimensional):
- the sun is i) not uniform in composition, and ii) physically deformed by its rotation;
- every body in the system which has any mass is contributing to the net curvature, regardless of how relatively-insignificant that mass is;
- everything is in motion at the same time;
- the question of whether gravitational effects are limited to 'c';
- etc..
Slan go foill!
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ta152h0
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by ta152h0 » Fri Jan 13, 2006 4:57 pm
Looks like gravity is strongest in the land of Foster's.........
Wolf Kotenberg
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astroton
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by astroton » Sat Jan 14, 2006 12:13 am
[quote="makc"]you came to relativity from wrong end. rather than asking numerous high-level questions, why wouldn't you 1st take a look at WHAT have changed since Newton?
Mak, I am not entirely oblivious to what has happened since Newton, however I don't pretend to be professional in this subject. My questions might sound silly to all those who have attained relatively higher state of mind than me.
But, some of the post Einstenian theories have been bit beffling to a simple mind like mine. Like someone had come up with "singularity" explaination for the Tunguska Blast, and it makes you wonder, if singularity did pass through the earth, why would not it collapse earth around it? Can Singularities exist in a form such that it can pass close to the earth or through earth without causing significant damage apart from damaging the landscape?
Just inquisitive mind...
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ta152h0
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by ta152h0 » Sat Jan 14, 2006 12:31 am
the math available to Einstein was much more developed than was available to Newton. Both brilliant thinkers. I would like to advance that Newtonian physics ( called classic ) and Quantum physics are not mutually exclusive, as the subject of the original post mat imply.
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Pass the ice cold one
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Wolf Kotenberg
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S. Bilderback
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by S. Bilderback » Sat Jan 14, 2006 4:19 am
But, some of the post Einstenian theories have been bit beffling to a simple mind like mine. Like someone had come up with "singularity" explaination for the Tunguska Blast, and it makes you wonder, if singularity did pass through the earth, why would not it collapse earth around it? Can Singularities exist in a form such that it can pass close to the earth or through earth without causing significant damage apart from damaging the landscape?
If the singularity had a small enough event horizon and was moving fast enough, it could pass through the Earth leaving little damage - in theory.
I would reserve a postulation of that type, (of the event actually happening), to science-fiction writers. A fragment of a neutron star would have a better probability of possible event.
The more I learn, the more I know what I don't know.
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Empeda2
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by Empeda2 » Tue Jan 17, 2006 12:16 pm
That's not the blast in 1908 is it? That was caused by a piece of comet Enke.
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astroton
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by astroton » Sat Jan 21, 2006 1:14 am
Empeda2 wrote:That's not the blast in 1908 is it? That was caused by a piece of comet Enke.
I recently read a book (written in 80's). Someone had theorised a space ship. Most Tungus at the time reported a cylindrical aboject, with blue tail or trail. While, Space Ship & Singularity theories were hard to digest, I thought comet Enke explaination was put to back burner.
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Empeda2
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by Empeda2 » Mon Jan 23, 2006 1:25 pm
I was under the impression that Enke did appear a lot smaller than expected after the explosion - mind you, that could just be because they were looking for it....
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Aqua
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by Aqua » Tue Jan 24, 2006 12:42 am
The Tunguska explosion may have been an air blast caused by a cometary fragment? OR, it may have been an incoming chunk of 'mirror matter'?
Something similar may have hit Jordan in 2001
http://www.jas.org.jo/mett.html
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astroton
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by astroton » Wed Jan 25, 2006 10:34 pm
very interesting article. Antimatter theory sounds good.
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astroton
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by astroton » Thu Jan 26, 2006 11:00 am
Nice 1 Aqua, espesially "the increased rate of biological mutations
was found not only within the epicenter area"