Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thebrain13 on 10/11/2009 00:56:08

Title: Can massive objects travel as fast as smaller objects?
Post by: thebrain13 on 10/11/2009 00:56:08
As an object travels near a black hole,(or any other source of mass) its speed is decreased, even lights. So I was wondering, would the maximum speed of an object decrease as a function of its mass?

You know, since the mass in a black hole is also under the influence of space curvature, would the maximum speed of heavier objects(like black holes)also be less than that of lighter objects(the speed of light)?
Title: Can massive objects travel as fast as smaller objects?
Post by: Mr. Scientist on 10/11/2009 02:00:05
It takes more energy to accelerate large objects than rather a quantum object. Needless to say a football could travel as fast as a particle, given the right conditions.
Title: Can massive objects travel as fast as smaller objects?
Post by: Bored chemist on 10/11/2009 19:22:53
From the point of view of a proton at the LHC any nearby footballs are moving very fast indeed.
Title: Can massive objects travel as fast as smaller objects?
Post by: litespeed on 10/11/2009 19:28:01
b13 - You wrote: "As an object travels near a black hole,(or any other source of mass) its speed is decreased..."

I assume this is a misprint and you meant INCREASES. In a vacuum all objects in a given gravitational field will accelerate at the same speed. There may be dissimilarities do to interaction with other matter entering the same gravitational field. Further, physically larger masses will get stretched apart a bit quicker.

However, assuming a black hole, all mass captured will be accelerated IMHO into relativistic speed collapse. To me this simply means the accelerated mass will approach the speed of light, and time dialation brings them to a practical stop, thus forming something like a flat shell about the center of mass, but never getting there.

I have been posing this scenario for more then a year, and I get zero responses from several accademic institutions I have contacted. Online, individuals have provided both supporting and contrary opinions. This leave me to the conclusion the matter has yet to be settled.
Title: Can massive objects travel as fast as smaller objects?
Post by: litespeed on 10/11/2009 19:47:44
BC

I would like your comment on this propostion.  Time/mass dialation of any given mass is subject to the ACCELERATION of the object, rather then the relative speed of the objects to begin with. Mental experiment.  An astronaut gets into his vessel, but does not apply power. He notices a star one light year away moving towards him at half the speed of light.

If he just sits there, all he needs to do is wait 1/2 year and the object will pass him. His time clock has not changed. But if he accelerates to 86% the speed of light (50%) time dialation, two things will happen. First ground control will observe intersection at a closing speed greater then the speed of light, and the astronaut will report an intersect of half THAT speed.

I just don't see anyway around this.


, he will notice he merges with the object in only a couple of months.
Title: Can massive objects travel as fast as smaller objects?
Post by: thebrain13 on 10/11/2009 20:33:56
I was not referring to speed changes due to gravitational acceleration. I was referring to speed changes, due to the ability of masses to alter geometry.(from general relativity) Light doesn't travel as fast when it is in the presence of mass. The closer an object is to a mass, and the bigger the mass, the slower it's maximum speed.

I was just wondering if that would mean that larger objects couldn't travel as fast, due to the fact that they are always near more mass than smaller objects.

I was thinking maybe, large objects would take the same amount of energy(per mass) to accelerate to the same velocity as smaller ones since frame dragging would cancel out the slowing down effect if you accelerated the entire mass. Where if you tried to accelerate a smaller object near a larger one the large object would pull on you. Would that be a correct conclusion?