Find hole in my retarted theory

Originally posted by Fischer3180
theoretically if a stick/rope/anything existed that met criteria you are trying to put forth in your statement. Than yes, the signal would reach the moon at a speed faster than the speed of light. So the only hole is that you cannot conduct that experiment within the laws of physics. If you thought that by the signal traveling at speeds greater than t ...[text shortened]... t, rather that "nothing with a given mass" can exceed that speed, relativity remains intact.

You are incorrect...
The rod's signal wouldn't reach the moon faster then light.
Signals or information traveling greater then speed of light violate laws of physics.
Wrote it some post ago...

Originally posted by serigado
You are incorrect...
The rod's signal wouldn't reach the moon faster then light.
Signals or information traveling greater then speed of light violate laws of physics.
Wrote it some post ago...

What is a stick, anyway? Even if we take a stick of pure diamond reaching from Earth to Moon, the signal can't go faster than light.

Matter consists of atoms. Atoms are puny nuclei of protons and neutrons, and some electrons of course. An atom is much bigger than that, something like 10 thousands wider in diameter than the nucleus. Then I don't know how separated the atoms are from eachother.

Between the atoms there is pure (?) vacuum. The forces holding the stick together is electromagnetic forces that acts through this vacuum.

So when you move the stick in one end, this mothion go from there to the other end of the stick with electromagnetic forces, acting from one atom by displacement to another. So the information about a displacement from one end of the stick to the other cannot ever go faster than light because light and electromagnetic forces are the same, only the medium differs.

Have I got it right?

Originally posted by FabianFnas
So when you move the stick in one end, this mothion go from there to the other end of the stick with electromagnetic forces, acting from one atom by displacement to another. So the information about a displacement from one end of the stick to the other cannot ever go faster than light because light and electromagnetic forces are the same, only the medium differs.

Have I got it right?

Light and electromagnetic forces are not the same, but I would agree that neither can travel faster than light, and that your argument in general is correct.

Originally posted by ivan2908
I was always wondered something which is pretty stupid but interesting. Theoretically if you connect Earth and moon with some indestructible rope (we are about 384000 km far away from the moon) and astronaut is holding one end of the rope on the moon, Earthling the second end... So lets say that man from earth pull the rope (ignore practical problems like h he would achieve that with most primitive device imaginable...

Any hole in my assumption ??

how about if the rope was a very light/ fine guitar string at high tension within a glass tube containing a vacuum. the string would vibrate rather than be pulled, saving energy,that is just plausible and gets around the problem of inertia.
i reckon tha due to the great length of the string, the vibration would behave like a wave and run along the string and end up slower than the speed of light. i dont believe you can compete with light. you'd be better off sending an electric pulse along the wire than a vibration.

Originally posted by twhitehead
Light and electromagnetic forces are not the same, but I would agree that neither can travel faster than light, and that your argument in general is correct.

Well, this is at the edge of my knowledge, so I understand that my reasoning might be flawed somewhere.

This is how I think of things, please correct me where I'm wrong:

Photons are particles carrying the electromagnetic energy. The elctromagnetic forces within an atoms and molecules are also electromagnetic in its nature, therefore its energy is also carried with photons. The difference is that these latter is emitted and absorbed quite quickly so they travel only very short distances in a very brief period of time.

So where I dislocate one of the atoms in a stick, a photon is generated and goes to a nearby atom and dislocate it as it is absorbed. This is done from atom to atom along the stick, and eventually to the other end of the stick where you can detect the dislocation.

Then we have the photino particle too. I don't know anything about them. And the virtual photon, which are emitted from nothing and absorbed in nothing. Are they something to be included in the hypothesis above?

Originally posted by FabianFnas
What is a stick, anyway? Even if we take a stick of pure diamond reaching from Earth to Moon, the signal can't go faster than light.

Matter consists of atoms. Atoms are puny nuclei of protons and neutrons, and some electrons of course. An atom is much bigger than that, something like 10 thousands wider in diameter than the nucleus. Then I don't know ho ...[text shortened]... ight and electromagnetic forces are the same, only the medium differs.

Have I got it right?

You got it pretty well. The information between successive atoms is passed through a "field", and fields propagate at a maximum speed (guess what? the speed of light).

Imagine that an electron was spontaneously created from thin air. The field created by the electron wouldn't be instantaneously created. Someone in mars would take a few minutes to detect the field. It's the same with the field between atoms in a chain, or lattice. A perturbation in an atom takes a while to be felt by the next atom. It's damn fast, but it's a finite time.

Originally posted by agryson
Guys, almost every scientific proposition is a thought experiment, givent hat the real world has so many complexities. Everything is a simplification. The important question is whther the thought experiment is TOO simplified. Given that the initial question was about realtivity, I really don't think that the ignoring of elasticity is going to affect the prem ...[text shortened]... cation, but so is the ideal gas law... that in itself doesn't stop the thing from working out.

Of course it does. The ideal gas law works under very specific conditions, as does sending messages via pulling on a stick. The conditions being discussed here are so radical that no set of rules that we're used to working under Earthly conditions can be relied upon.

Otherwise we might as well say that you can go the speed of light; just keep accelerating! Newtonian laws work well on Earth...who needs relativity?

Originally posted by AThousandYoung
Newtonian laws work well on Earth...who needs relativity?

My GPS.

Originally posted by ivan2908
I was always wondered something which is pretty stupid but interesting. Theoretically if you connect Earth and moon with some indestructible rope (we are about 384000 km far away from the moon) and astronaut is holding one end of the rope on the moon, Earthling the second end... So lets say that man from earth pull the rope (ignore practical problems like h ...[text shortened]... he would achieve that with most primitive device imaginable...

Any hole in my assumption ??

i think people will claim there are holes but the truth is this would be faster than the speed of light... i like this idea.... of course its impossible, but you could look on it another way, tie a piece of string to a bell and pull the string, the bell rings, walk a mile away and keeping the string tight, pull it, the bell rings, in theory, you could be a million miles away and the bell will still ring.... a piece of string, quicker than the speed of light...

i believe that everything that we see - being any form of compound, bound by electrostatic attraction and thus forming a solid, liquid or gas, will then be bound by those same limited bonds, and therefore develop an elastic material property

to extend beyond this field strength - breaks the bond , and therefore breaks the field

engineers typically refer to material properties as yield strength , youngs modulus, ...(etc), in materials that are worth considering as structural conduits for transferring forces

if the force is great enough, you've simpy broken your model - try again, it gets bigger and bigger until it works, much like church structures during the dark ages, buttress piers simply got bigger until the building actually stood up

if you also consider the gravitational attraction from earth to the moon, the element (unless weightless, also an impossibility) when you integrate over the distance of attraction from earth, and then the moon - would require a very very very heavy end at the moon side so as not to fall back to earth - dragging said astronaut with it...

then the rope/string/element would need to be positioned at the pole so the humanoid wouldn't have to run very fast, at least the astronaut fares well at this point - always facing earth from the same spot..

however, gravity is a b%$ch, the rope would be tugged into a parabolic catenary sag and not be straight any longer - so is now a cable reliant on multiple force systems to maintain equilibrium. ( the poles are not in line with the string connecting moon to earth, so there would be a lateral component on the cable for a considerable distance away from the surface of the earth, but not necessarily so from the moon side)

the tug would then resort to a wave force similar to a wave in the ocean, a wave on a string, etc, and thence travel as such to the moon... albeit a bit slower than the speed of light

so stop the earth spinning, and you have a chance

Originally posted by olddog
...then the rope/string/element would need to be positioned at the pole so the humanoid wouldn't have to run very fast, at least the astronaut fares well at this point - always facing earth from the same spot ...

Even here we have a problem.
The orbit of moon around the Earth is only halfway in orbit north than the equator, the other half is south of the equator. (The equator and the orbit of moon is not paralell.)
To attach a rope at the north pole it has to be at the top of a vere (and I mean very!) high mast.

Originally posted by olddog
i believe that everything that we see - being any form of compound, bound by electrostatic attraction and thus forming a solid, liquid or gas, will then be bound by those same limited bonds, and therefore develop an elastic material property

to extend beyond this field strength - breaks the bond , and therefore breaks the field

engineers typically refer ...[text shortened]... beit a bit slower than the speed of light

so stop the earth spinning, and you have a chance

You're right. The experience was conceptual, ignoring gravity.
Yet, I don't think it would be a catenary. The catenary is the solution of the differential equation for constant gravity. The gravity would change here as (1/r²😉 (in fact, there would be two gravitational sources), turning the equation highly non-linear and non-catenary.