What happens when two length contracted ladders move through the same garage?

  • Thread starter Thread starter kmarinas86
  • Start date Start date
  • Tags Tags
    Paradox
kmarinas86
Messages
974
Reaction score
1
kmarinas86 said:
Figure 4: Scenario in the garage frame: a length contracted ladder entering and exiting the garage
250px-Ladder_Paradox_GarageScenario.svg.png


Figure 5: Scenario in the ladder frame: a length contracted garage passing over the ladder
250px-Ladder_Paradox_LadderScenario.svg.png

So what happens if we have TWO ladders moving in opposite directions through the same garage?

Figure 4: Scenario in the garage frame: a length contracted ladder entering and exiting the garage

attachment.php?attachmentid=44017&stc=1&d=1329437190.png


Figure 5: Scenario in the ladder frame: a length contracted garage passing over the ladder

attachment.php?attachmentid=44018&stc=1&d=1329437190.png


Something's amiss.

How, in the last diagram, does the second ladder (the one faster than garage) spend LESS time inside the garage so that (unlike as depicted in the last diagram) the faster ladder doesn't hit the doors of the garage.
 

Attachments

  • 250px-(DOUBLE)Ladder_Paradox_GarageScenario.svg.png
    250px-(DOUBLE)Ladder_Paradox_GarageScenario.svg.png
    3.1 KB · Views: 580
  • 250px-(DOUBLE)Ladder_Paradox_LadderScenario.svg.png
    250px-(DOUBLE)Ladder_Paradox_LadderScenario.svg.png
    4.4 KB · Views: 585
Last edited:
Physics news on Phys.org
In Fig 5 you have both ladders entering simultaneously. That's incompatible with them entering simultaneously in Fig 4. (Ditto exiting.)
 
DrGreg said:
In Fig 5 you have both ladders entering simultaneously. That's incompatible with them entering simultaneously in Fig 4. (Ditto exiting.)

Thanks.
 
I asked a question here, probably over 15 years ago on entanglement and I appreciated the thoughtful answers I received back then. The intervening years haven't made me any more knowledgeable in physics, so forgive my naïveté ! If a have a piece of paper in an area of high gravity, lets say near a black hole, and I draw a triangle on this paper and 'measure' the angles of the triangle, will they add to 180 degrees? How about if I'm looking at this paper outside of the (reasonable)...
The Poynting vector is a definition, that is supposed to represent the energy flow at each point. Unfortunately, the only observable effect caused by the Poynting vector is through the energy variation in a volume subject to an energy flux through its surface, that is, the Poynting theorem. As a curl could be added to the Poynting vector without changing the Poynting theorem, it can not be decided by EM only that this should be the actual flow of energy at each point. Feynman, commenting...
Back
Top