The Naked Scientists

The Naked Scientists Forum

Author Topic: Spaghettification vs. length contraction - which one wins?  (Read 2938 times)

Offline LeeE

  • Neilep Level Member
  • ******
  • Posts: 3382
    • View Profile
    • Spatial
YABHS (Yet Another Black Hole Scenario)

You are an observer watching an object falling into a BH.  As it accelerates it will appear to contract in length, in accordance with GR.  However, at the same time, it will start to lengthen due to spaghettification.

Does this mean that you could end up seeing an object moving at relativistic speed but with no apparent foreshortening?

Working out the foreshortening factor is easy enough but I'm not so sure about the spaghettification lengthening factor to work out if they cancel.  The fact that both phenomenom arise from the same and equal cause suggests that they might but this would seem to contradict GR.


 

Offline LeeE

  • Neilep Level Member
  • ******
  • Posts: 3382
    • View Profile
    • Spatial
Spaghettification vs. length contraction - which one wins?
« Reply #1 on: 04/07/2008 00:55:17 »
Okay - we can postulate an immensely huge rocket (lots of fuel) that slowy approaches a BH.  It's great mass will not make it accelerate more quickly than a lighter rocket, so spaghettification would seem to dominate over foreshortening.  This isn't a free-fall siituation though - energy is being supplied and must be accounted for.
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
Spaghettification vs. length contraction - which one wins?
« Reply #2 on: 04/07/2008 06:35:15 »


I dunno. I'm just a dumb rodent
 

The Naked Scientists Forum

Spaghettification vs. length contraction - which one wins?
« Reply #2 on: 04/07/2008 06:35:15 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums