Are you sure that objects which moves enought fast are not black holes?

In summary: If light can escape to infinity, the object is not a black hole.In summary, the creation of a gravitational field by a mass is not dependent on its relativistic mass, as even a moving object that does not become a black hole still has a gravitational field. However, the velocity of an object can affect the strength and direction of its gravitational field, as seen through the tidal force. Nonetheless, the determination of whether an object is a black hole or not is based on its ability to trap light, which is not affected by its velocity.
  • #1
Born2Perform
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In order that any mass creates a gravitational field, if those objects do not become black holes, this means that relativistic mass does not create a grav field.

How can a mass increasing not produce a deeper space warp? That is the mass does not increase with speed?
Apologies my english.
 
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  • #2
Born2Perform said:
In order that any mass creates a gravitational field, if those objects do not become black holes, this means that relativistic mass does not create a grav field.

How can a mass increasing not produce a deeper space warp? That is the mass does not increase with speed?
Apologies my english.

Yes.

See the sci.physics.faq http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/black_fast.html" [Broken]

Whether an object is a black hole or not is a global property of the object. Therfore if an object is not a black hole in it's rest frame, it is not not a black hole if you whiz by it at a high velocity.

The gravitational field of an object can change when its velocity changes. This can most easily be seen by means of the tidal force.

If you move at "right angles" to an object, the tidal force you experience will be greater than if you were standing still.

Interestingly enough, however, if you move directly towards or away from a massive object, the tidal force you experience will not change (it will be the same as if you were not moving).

You can find the later fact in MTW's "Gravitation" (page numbers on request).

This demonstrates that velocity can change "gravity". It also helps illustrate how the gravity from a moving object is not symmetrical. It is stronger "to the sides" than it is in front or in back. This is similar in general behavior (though not in exact detail) to how the electric field from an electric charge acts.

What's important as far as an object being a black hole or not is whether or not light can escape from it. That does not change when the velocities object changes.
 
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  • #3
pervect said:
What's important as far as an object being a black hole or not is whether or not light can escape from it. That does not change when the velocities object changes.
Hmmmm, is that correct?
Does not something happen to the visibility of particles leaving or entering an object during a change in velocity?
 
  • #4
Consider the rest frame of the object. Light leaves it and escapes to infinty.

Now consider the object in a moving frame. Light abberrates, but it still escapes to infinity.

For an object to be a black hole, light must be trapped by the object.
 

1. What is a black hole?

A black hole is a region of space with a gravitational pull so strong that nothing, including light, can escape from it. It is formed when a massive star dies and collapses under its own weight.

2. How fast do objects need to be moving to potentially become a black hole?

The speed required for an object to become a black hole is called the escape velocity, which depends on the mass of the object. For example, the escape velocity for Earth is approximately 11.2 kilometers per second.

3. Why are objects that move fast not necessarily black holes?

Objects that move fast may have a high enough escape velocity to become a black hole, but they also need to have a large enough mass. Most objects that move fast, such as planets and stars, do not have enough mass to become a black hole.

4. How can we tell if an object is a black hole or not?

Scientists use various methods to detect black holes, such as observing their effects on nearby objects or detecting radiation emitted from matter falling into the black hole. They also look for specific characteristics, such as a strong gravitational pull and an event horizon, which is the point of no return for objects entering the black hole.

5. Is it possible for an object to become a black hole without moving at all?

Yes, it is possible for an object to become a black hole without moving at all. As mentioned earlier, the mass of an object plays a critical role in determining whether it becomes a black hole, regardless of its speed or lack thereof.

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