[lyner]

Yup!

[thinkoutsidethe]

Force can travel faster than the speed of light as far as i'm concerned. In fact how could the universe maintain its stability and form if that was not the case? its impossible otherwise. All these interconnections are somehow unconnected as a whole?

Let me put it a different way. You have a steel tube which is longer than meters c. At one end of the tube you have a plunger and push with a massive force. The other end is blocked. Whilst maintaining the pressure on the plunger you release the blocked end. The pressure will instantaneously burst.

Sure the observer won't be able to see this event because he can only use light as an observing factor. But having two timed clocks at either end will prove the effect.

I feel like this is a fundamental floor in the train sequence of relativity. Einstein was using light as a reference. Just because something is not sighted does not mean it does not exist. In fact the whole night sky as we see it is not the universe as it is but rather how our eyes perceive it. It is totally warped by time because each point is travelling to our eyes from different distances and hence have a different time continuum. One photon has traveled 6  years and another 7  years. What you are seeing is different points in time in space.

 

[imatfaal]

Force can travel faster than the speed of light as far as i'm concerned. In fact how could the universe maintain its stability and form if that was not the case? its impossible otherwise. All these interconnections are somehow unconnected as a whole?

Intuition often fails in astronomical calculations - and those involving einstein's theories.  Our theories currently do no have force transferred instantaneously - or if you are using a formulation without forces, then the interaction is still limited to SoL.

Let me put it a different way. You have a steel tube which is longer than meters c. At one end of the tube you have a plunger and push with a massive force. The other end is blocked. Whilst maintaining the pressure on the plunger you release the blocked end. The pressure will instantaneously burst.

Nope - this is testable and false.  A pressure wave will travel from one end to the other at about the speed of SOUND within the material.

Sure the observer won't be able to see this event because he can only use light as an observing factor. But having two timed clocks at either end will prove the effect.

  Whilst using light to observe can introduce interesting extra factors - this form of experiment is not a problem as we can observe that the effect is transferred at far lower than SoL

I feel like this is a fundamental floor in the train sequence of relativity. Einstein was using light as a reference. Just because something is not sighted does not mean it does not exist. In fact the whole night sky as we see it is not the universe as it is but rather how our eyes perceive it. It is totally warped by time because each point is travelling to our eyes from different distances and hence have a different time continuum. One photon has traveled 6  years and another 7  years. What you are seeing is different points in time in space.

  Basically Special Relativity is as well proven as any theory is gonna get - it could still be wrong, but the only thing that will show it is wrong is experimental data

 

[syhprum]

c

[LetoII]

in case of entanglement, instantly....

[imatfaal]

Letoll - not sure about that at all.  There is no transfer of information (and a force would imply that) which travels faster than c.  Entanglement is a lovely sci-fi buzz word (and a highly serious physics subject) - but it most certainly does not allow greater than c communication of any information.

[Phractality]

Letoll - not sure about that at all.  There is no transfer of information (and a force would imply that) which travels faster than c.  Entanglement is a lovely sci-fi buzz word (and a highly serious physics subject) - but it most certainly does not allow greater than c communication of any information.

It's not that info isn't transferred FTL; but a second message must follow at the speed of light before the information can be extracted. So entanglement cannot communicate FTL.
However, if it can be verified after a SOL delay that the info was transferred instantaneously, that would prove that there is a preferred reference frame. Special relativity proves that nothing can be simultaneous at different location in all reference frames. A good candidate for the preferred reference frame is the CMB, relative to which our solar system is moving toward Virgo at about 627 km/s (different sources give different speeds). The SR formula for time as a function of position in the direction of motion is
t' = γ(t-vx/c²)
So clocks synchronized in Earth's frame have different times in the CMB frame at the rate of 9 ns/km. Earth clocks closer to Virgo show later times. A transfer of information across 10 km in the direction of Virgo, which is instantaneous in the CMB frame, would arrive 90 ns before it is sent according to Earth clocks. This does not violate causality because info sent back to the starting point would be delay by the same amount. If this method could be used for instantaneous communication (which it probably can't), the 2-way communication would be instantaneous, but you could not send a message into your own past.

[kowalskil]

is the transmission of force instantaneous? if yes does this mean information travels faster than light?

if I have a long stick, say 10 light years long, OK so its a really long stick. If I push on the near end of the stick, how long until the force can be measured at the far end of the stick? does it take 10 years?

I would have thought it would go much slower than the speed of light - the speed of sound would be what I would expect in that particular instance.

Me too.

[Robro]

I think force propagates at the speed of light, although, as force travels through various mediums there is a loss in efficiency due to reaction times in molecules and atoms. Use the force Luke.

[davidk]

You can hear a train coming down the line (don't try this at home) because the forces are propagating along the steel in the track

I'm glad you warned me not to try this at home.