Two Questions about Black Holes and Laws of Physics

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Discussion Overview

The discussion revolves around two questions related to black holes and the distinction between scientific theories and laws. The first question addresses the nature of gravitational force at the event horizon of a black hole, particularly whether it can be equated to the speed of light. The second question explores the criteria that elevate a scientific theory, such as relativity, to the status of a law.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants suggest that at the event horizon of a black hole, the gravitational force could be related to the speed of light, but clarify that speed is a relative concept and depends on the reference frame.
  • One participant notes that while falling into a black hole, an object can increase in speed but cannot reach the speed of light, as only photons travel at that speed.
  • Another participant emphasizes that a force is not a speed and that to remain stationary relative to a black hole, one would need a local coordinate velocity of the speed of light at the event horizon.
  • There is a claim that there is no real difference between an accepted theory and a law, though laws can often be expressed in concise statements.
  • One participant argues that theories do not become laws, but rather that the axioms and implications of a theory constitute its laws.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between gravitational force and the speed of light at the event horizon, as well as on the distinction between theories and laws. The discussion remains unresolved with multiple competing perspectives presented.

Contextual Notes

There are limitations in the discussion regarding the definitions of force and speed, as well as the criteria for distinguishing between theories and laws. These aspects are not fully explored or agreed upon by participants.

mrjeffy321
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here are two kinda simple questions that I wanted to ask, just to clairify something for me.

1. at the event horizon of a black hole, the gravitational force pulling you towards the center, should be the speed of light correct?, and/or inside the event horizon aswell, equal to (or greater than) the speed of light?

2.how does a theory become a law, for example the theory of relativity, which has been show to be correct under many circumstances, and the 3 laws of motion.
I know it takes along time of extensive testing to make sure it is correct, but is there anything that makes it official or pushes it over the edge of being a law.
 
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mrjeffy321 said: here are two kinda simple questions that I wanted to ask, just to clairify something for me.

1. at the event horizon of a black hole, the gravitational force pulling you towards the center, should be the speed of light correct?, and/or inside the event horizon aswell, equal to (or greater than) the speed of light?

2.how does a theory become a law, for example the theory of relativity, which has been show to be correct under many circumstances, and the 3 laws of motion.
I know it takes along time of extensive testing to make sure it is correct, but is there anything that makes it official or pushes it over the edge of being a law.
Well, since you seem to be talking of relativity, you should ask yourself what a black hole is. Yes, it is a severe curviture in space (time) do to a very large concentrated mass.But then again, what is the curviture of spacetime due to relativity? Yes, it is gravity.

Say you have a trampoline. This is spacetime. You put a concentrated mass in the center. (say a marble that weighs as much as a bowling ball) Now there is no doubt that if you roll a marble that weighs normal to the event horizon (or where spacetime starts to curve), it will not all of a sudden drop at the speed of light, but it will travel very fast.

I hope that answers one of your questions at least.

Paden Roder
 
1. at the event horizon of a black hole, the gravitational force pulling you towards the center, should be the speed of light correct?, and/or inside the event horizon aswell, equal to (or greater than) the speed of light?

Speed is a relative concept, so you must specify the reference frame. I'll assume you want the frame of the black hole. If you are falling into a black hole, you can be at any speed. As you accelerate, you will increase in mass as well as speed, but never get to the speed of light. Only photons go at the speed of light.
 
mrjeffy321 said:
here are two kinda simple questions that I wanted to ask, just to clairify something for me.

1. at the event horizon of a black hole, the gravitational force pulling you towards the center, should be the speed of light correct?, and/or inside the event horizon aswell, equal to (or greater than) the speed of light?

2.how does a theory become a law, for example the theory of relativity, which has been show to be correct under many circumstances, and the 3 laws of motion.
I know it takes along time of extensive testing to make sure it is correct, but is there anything that makes it official or pushes it over the edge of being a law.

1. A force is not a speed, however at the event horizon you need a local co-ordinate velocity of c in order to remain sationery, as viewed by a remote observer, wrt to the black hole within the event horizon you need a velcoity greater than c.

2. no real difference between an accepted theory and a law. but a law can usually be put into a concise statement.
 
mrjeffy321 said:
here are two kinda simple questions that I wanted to ask, just to clairify something for me.

1. at the event horizon of a black hole, the gravitational force pulling you towards the center, should be the speed of light correct?, and/or inside the event horizon aswell, equal to (or greater than) the speed of light?

Force is not speed.

2.how does a theory become a law, for example the theory of relativity, which has been show to be correct under many circumstances, and the 3 laws of motion.
I know it takes along time of extensive testing to make sure it is correct, but is there anything that makes it official or pushes it over the edge of being a law.

Theories do not become laws. The axioms and implications of a theory are the laws of the theory. For example that force is proportional to acceleration or f = ma is a law of Newtonian mechanics. Also for example, that four-force is proportional to four-acceleration or F = mA, is a law of general relativity. That charge is conserved is a law of modern electrodynamics. All of these are examples of our representations of laws of physics.
 

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