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View Full Version : There are may be short cuts in respect of the distance between two planetory objects!



suntrack2
2007-Oct-07, 01:35 PM
See, we know that between the two planets how much is the distance, but as far as space situation is concern do you think that there is also a possibility in the space map that the distance may be cover by using short cut path in the space to receive a shorter distance between the two planets.

As we know that the distance of aireal is lower than the distance from the ground position of any desired destination.

So does this question any meaning?

(in the attached self made digram I have point out the probable short distance with yellow line, and exactly near digram the short distance is shown by the red colour. )

hhEb09'1
2007-Oct-07, 02:33 PM
As we know that the distance of aireal is lower than the distance from the ground position of any desired destination. Is that comment about distances on the surface of the earth? If so, I'd say that that is false.

Do you mean something else?

Delvo
2007-Oct-07, 06:30 PM
I think you just collided with a language barrier. I don't understand what you're saying.

astromark
2007-Oct-07, 06:35 PM
If your target is moving... then aim for where it will be not where it is... what else are you asking?

neilzero
2007-Oct-07, 07:20 PM
The as the crow flies distance = straight line distance is quite close for objects in our solar system, if we can accelerate at a million g to several tenths of the speed of light; then declerate fast, if we want to land at our destination. At slow accellerations to a few kilometers per second, average, over the path, chosing the optimum path gets very complicated, because most everthing is moving at high speed in a curved path with respect to most everything else. There are, however, several traditional ways of doing it which are close to optimum in many senarios. One of our resident rocket scientists will need to explain some examples in detail. Neil

a1call
2007-Oct-08, 12:00 AM
If the "Universe is finite but unbounded" notion is true then there may be infinite number of shorter paths than a straight line drawn between 2 points in any given 3 dimensions.

astromark
2007-Oct-08, 06:33 AM
If the "Universe is finite but unbounded" notion is true then there may be infinite number of shorter paths than a straight line drawn between 2 points in any given 3 dimensions.

I am the thick moron that needs this explained properly and in depth. Is this some sort of joke?
I find that quoted statement impossible to understand as a statement of facts. It can not be true.
I will except that curvature is a buy product of movement of both target and source. The shortest path between two points must be a straight line always.
Do you see things differently?
Well there you are, you have set a trap and, I have taken the bait.

Neverfly
2007-Oct-08, 06:43 AM
Maybe he's referring to "slip-streaming" or something...

Michael Noonan
2007-Oct-08, 06:43 AM
I am the thick moron that needs this explained properly and in depth. Is this some sort of joke?
I find that quoted statement impossible to understand as a statement of facts. It can not be true.
I will except that curvature is a buy product of movement of both target and source. The shortest path between two points must be a straight line always.
Do you see things differently?
Well there you are, you have set a trap and, I have taken the bait.

Not at all, I reserve the right to having 'joke' status. At least you don't have solid objects shimmering transparently and people evolving into machines.

As for straight lines with a constant but small acceleration a curve may give better results but only because the trajectory can be optimised for different parts of the flight curve and angles defined for launch and re-entry.

It isn't the shortest path distance wise but may be time-wise for a crew travelling between planets :)

astromark
2007-Oct-08, 07:31 AM
Well yes because we use orbital mechanics and velocities stolen then yes the slingshot trajectory does work well. I great deal more fuel (energy) would be required to travel that shortest possible distance. Regardless of that fact. The shortest distance between two points is a straight line. Its not the same question to say the shortest trip time is a curve. That is only true because of our limitations of technology.

Jerry
2007-Oct-08, 08:11 PM
There is also the issue of gravimetric bending of light - the light path between two objects on nearly opposite sides of the sun will not be the shortest path geometrically, but it will be the shortest path in terms of time-of-flight.

a1call
2007-Oct-08, 08:33 PM
I find that quoted statement impossible to understand as a statement of facts. It can not be true.


You are certainly not alone, regardless:



Einstein's theories (never mind that they have checked out in reality) are incredible: space is curved; the shortest distance between two points is not a straight line; the universe is finite but unbounded; parallel lines eventually meet; ...


Source (http://www.blupete.com/Literature/Biographies/Science/Einstein.htm)

John Mendenhall
2007-Oct-11, 02:53 PM
You are certainly not alone, regardless:



Source (http://www.blupete.com/Literature/Biographies/Science/Einstein.htm)

Be cautious of your sources. Your quoted material is from an online biography of Einstein rather than a physics text, and I think the finite but unbounded and parallel lines parts are respectively undetermined and incorrect. The shortest distance between two points is a geodesic, which is probably curved. The Wiki article on manifolds is helpful.

a1call
2007-Oct-11, 03:20 PM
Be cautious of your sources. Your quoted material is from an online biography of Einstein rather than a physics text, and I think the finite but unbounded and parallel lines parts are respectively undetermined and incorrect. The shortest distance between two points is a geodesic, which is probably curved. The Wiki article on manifolds is helpful.

The "universe is finite but unbounded" notion is a very famous and often referenced model of universe. I am surprised that so many people here have never heard of it. It can be traced back to lectures by Einstein himself and are well documented on the net. You might want to research it yourself.

dhd40
2007-Oct-11, 05:06 PM
There is also the issue of gravimetric bending of light - the light path between two objects on nearly opposite sides of the sun will not be the shortest path geometrically, but it will be the shortest path in terms of time-of-flight.

Is there a difference between "line" and "path"? I would say yes: "Line" is purely geometric (in 3D space) whereas "path" may be something completely differnet in a gravitational, electric, magnetic, spacetime, etc field.
astromark is absolutely right in the geometric-line-view, others may be right in a field-view.

Click Ticker
2007-Oct-11, 07:53 PM
The shortest distance between where I live and China is to dig a hole. But it's certainly not the path of least resistance. Unfortunately I'm limited by technology (and probably the laws of physics as well - at least until I can get my hands on some unobtainium).

G O R T
2007-Oct-11, 11:14 PM
As we know that the distance of aireal is lower than the distance from the ground position of any desired destination.


This seems to be a misinterpretation of the difference between Rhumb routes and Great Circle routes, as plotted on a Mercator projection map or globe respectively.

In this case the difference in distance between points is not actually real, but a longer route may be chosen for simplicity.

mugaliens
2007-Oct-12, 12:41 AM
Is it possible? Yes. But not by any means we understand at this time.

So I'd have to say the liklihood is pretty low.

hhEb09'1
2007-Oct-14, 12:09 AM
This seems to be a misinterpretation of the difference between Rhumb routes and Great Circle routes, as plotted on a Mercator projection map or globe respectively.That's kinda what I was thinking too, why I made my comment, but I wasn't sure.

DyerWolf
2007-Oct-15, 06:19 PM
~snip~ at least until I can get my hands on some unobtainium).

I know where some is - but you can't have it.

John Mendenhall
2007-Oct-15, 06:56 PM
The "universe is finite but unbounded" notion is a very famous and often referenced model of universe. I am surprised that so many people here have never heard of it. It can be traced back to lectures by Einstein himself and are well documented on the net. You might want to research it yourself.

You're right, after I posted I did go back and check. There are good arguments for finite but unbounded, it gives a better fit than anything else. But I would quibble that it isn't conclusive.

John Mendenhall
2007-Oct-15, 07:02 PM
Unfortunately I'm limited by technology (and probably the laws of physics as well - at least until I can get my hands on some unobtainium).



The world's entire supply is being held by a certain notorious invisible elf.