The Naked Scientists

The Naked Scientists Forum

Author Topic: What could cause the earth to lose its gravity?  (Read 15124 times)

Offline kyscreth

  • First timers
  • *
  • Posts: 1
    • View Profile
What could cause the earth to lose its gravity?
« on: 02/10/2009 08:25:35 »
Does anyone have any ideas how the earth or any other planet could lose its gravity?? either over a long or short amount of time..
any ideas would be appreciated, cheers.
 


 

Offline Mr. Scientist

  • Neilep Level Member
  • ******
  • Posts: 1451
  • Thanked: 2 times
  • http://www.facebook.com/#/profile.php?ref=profile&
    • View Profile
    • Time Theory
What could cause the earth to lose its gravity?
« Reply #1 on: 02/10/2009 08:29:02 »
Only one solution. A loss of gravity would mean a loss of mass.
 

Offline syhprum

  • Neilep Level Member
  • ******
  • Posts: 3821
  • Thanked: 19 times
    • View Profile
What could cause the earth to lose its gravity?
« Reply #2 on: 02/10/2009 15:39:28 »
When LHC gets going and drops a dreaded blackhole into the centre of the Earth causing it to collapse almost instantly into a 50 millmeter radius ball we who are living 6400 Km from the the centre at present will notice an immediate loss of gravity.
This will not last long as we drop towards the centre very gently at first it will rapidly increase and reach a quite uncomfortable level!.
 

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
What could cause the earth to lose its gravity?
« Reply #3 on: 02/10/2009 18:14:55 »
Will it help if I am upon an airomobile when this happens ?
 

Offline LeeE

  • Neilep Level Member
  • ******
  • Posts: 3382
    • View Profile
    • Spatial
What could cause the earth to lose its gravity?
« Reply #4 on: 02/10/2009 19:31:40 »
When LHC gets going and drops a dreaded blackhole into the centre of the Earth causing it to collapse almost instantly into a 50 millmeter radius ball we who are living 6400 Km from the the centre at present will notice an immediate loss of gravity.
This will not last long as we drop towards the centre very gently at first it will rapidly increase and reach a quite uncomfortable level!.

The Schwarzchild radius for the Earth is a little under 9mm, iirc.  Were the Earth to be instantly transformed into such a black hole there would be no change in the 'strength' of gravity at the original radius of the Earth i.e. where it's surface was.  There would be no loss of gravity and anything left there would just start accelerating towards the center at 1G.

If a micro black hole were to fall into the Earth from its surface, the Earth would not collapse almost instantly; the fastest that the surface could collapse would still be 1G and in fact it's likely that the Earth would take quite some time to collapse, probably over a period of days to months.  The micro-BH would oscillate back and forth through the Earth, initially with relatively little slowing, but getting slower with each pass and eventually settling at the center.  As matter fell into the micro-BH energy would be released by the in-falling matter, effectively producing a back-pressure that would slow the rate of further in-fall.  Although the collapse would start slowly, it would speed up over time and total effective collapse would be inevitable in the end.
 

Offline syhprum

  • Neilep Level Member
  • ******
  • Posts: 3821
  • Thanked: 19 times
    • View Profile
What could cause the earth to lose its gravity?
« Reply #5 on: 02/10/2009 20:59:00 »
I did not expect my post to be taken too seriously but I am pleased to see any serious analyses of the scenario.
« Last Edit: 02/10/2009 21:07:52 by syhprum »
 

Offline RD

  • Neilep Level Member
  • ******
  • Posts: 8130
  • Thanked: 53 times
    • View Profile
What could cause the earth to lose its gravity?
« Reply #6 on: 02/10/2009 21:08:45 »
What about the  Lagrange point L1 ? where gravity is cancelled out.
http://en.wikipedia.org/wiki/Lagrangian_point
 

Offline syhprum

  • Neilep Level Member
  • ******
  • Posts: 3821
  • Thanked: 19 times
    • View Profile
What could cause the earth to lose its gravity?
« Reply #7 on: 30/11/2009 14:46:25 »
If mathematicians found serious errors in Einstein and Newtons calculations
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11993
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
What could cause the earth to lose its gravity?
« Reply #8 on: 13/12/2009 00:04:26 »
Gravity is related to mass and acceleration. As soon as you stop accelerating you become 'weightless' if in space. So to get to a state without gravity I think you would need to be as far away from any mass and acceleration as possible.
 

Offline Mr. Scientist

  • Neilep Level Member
  • ******
  • Posts: 1451
  • Thanked: 2 times
  • http://www.facebook.com/#/profile.php?ref=profile&
    • View Profile
    • Time Theory
What could cause the earth to lose its gravity?
« Reply #9 on: 13/12/2009 00:38:40 »
Does anyone have any ideas how the earth or any other planet could lose its gravity?? either over a long or short amount of time..
any ideas would be appreciated, cheers.
 

Not without the absence of the matter earth is comprised of. :)
 

Offline Mr. Scientist

  • Neilep Level Member
  • ******
  • Posts: 1451
  • Thanked: 2 times
  • http://www.facebook.com/#/profile.php?ref=profile&
    • View Profile
    • Time Theory
What could cause the earth to lose its gravity?
« Reply #10 on: 13/12/2009 00:39:25 »
Or a gradual but long gravitational radiation.
 

Offline Mr. Scientist

  • Neilep Level Member
  • ******
  • Posts: 1451
  • Thanked: 2 times
  • http://www.facebook.com/#/profile.php?ref=profile&
    • View Profile
    • Time Theory
What could cause the earth to lose its gravity?
« Reply #11 on: 13/12/2009 00:40:20 »
Gravity is related to mass and acceleration. As soon as you stop accelerating you become 'weightless' if in space. So to get to a state without gravity I think you would need to be as far away from any mass and acceleration as possible.

Listen to this one - he is also true.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11993
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
What could cause the earth to lose its gravity?
« Reply #12 on: 25/12/2009 07:13:51 »
Nah not really, but thanks all the same Mr S. Thinking of it you need to get outside SpaceTime to get out of gravitational influences. The universe binds together by gravity so?
 

Offline Pmb

  • Neilep Level Member
  • ******
  • Posts: 1838
  • Physicist
    • View Profile
    • New England Science Constortium
What could cause the earth to lose its gravity?
« Reply #13 on: 27/12/2009 03:14:42 »
When LHC gets going and drops a dreaded blackhole into the centre of the Earth causing it to collapse almost instantly into a 50 millmeter radius ball we who are living 6400 Km from the the centre at present will notice an immediate loss of gravity.
This will not last long as we drop towards the centre very gently at first it will rapidly increase and reach a quite uncomfortable level!.
That is not true. We'd never know the difference if our distance from the center of the Earth remained the same.
 

Offline syhprum

  • Neilep Level Member
  • ******
  • Posts: 3821
  • Thanked: 19 times
    • View Profile
What could cause the earth to lose its gravity?
« Reply #14 on: 27/12/2009 10:08:54 »
LeeE has published a more detailed account of what will happen.
 

Offline questioner

  • Jr. Member
  • **
  • Posts: 22
    • View Profile
What could cause the earth to lose its gravity?
« Reply #15 on: 31/12/2009 00:52:15 »
Gravity gets weaker as we travel away from the earth so it must be stronger as we get closer to the centre. The density in the centre of the earth must be immense. If you could remove the core of the planet wouldn't it collapse into dust.

 

Offline Geezer

  • Neilep Level Member
  • ******
  • Posts: 8328
  • "Vive la résistance!"
    • View Profile
What could cause the earth to lose its gravity?
« Reply #16 on: 31/12/2009 06:44:15 »
Gravity gets weaker as we travel away from the earth so it must be stronger as we get closer to the centre. The density in the centre of the earth must be immense. If you could remove the core of the planet wouldn't it collapse into dust.



Er well, no. If you were able to survive at the centre of the Earth, the Earth would exert no gravitational force on you at all. The mass of the Earth would be equally distributed around you in three dimensions, so the gravitational forces from the Earth's mass would sum to zero.
 

The Naked Scientists Forum

What could cause the earth to lose its gravity?
« Reply #16 on: 31/12/2009 06:44:15 »

 

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