Confusing Scientific Thought experiment of mine?

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Okay and how you gonna do that? I mean, without using a black hole...


I talked about it in previous posts look back.

Are we now at least in agreement on this point (that gravitational measurements outside of Earth's reference frame remain the same)?


Yes and No, because giving it a quick rethink says that due to Lorentz-Fitzgerald contraction all masses on the body or objects at motion should grow proportionate to its increase of gravity to that of other body in our case a human and earth so the gravity will increase exponentially but it will be proportionate to that of the other bodies at motion or on the body such as Humans and such.

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I talked about it in previous posts look back.


But yet did not find a satisfactory method. You have to consider that what you're trying to do here is probably violating physics somewhere. You can't simply carry more fuel to keep this thing accelerating, because this will need to also be accelerated, by more fuel, which also needs accelerating by more fuel...

Apart from propelling things with fuel, the only other way of propulsion is gravitational fields. So I'm saying, how are you going to do this without using a black hole's gravitational field (which is the only gravitational field with enough strength)?

I honestly couldn't follow what was in your yes and no explanation?

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I still think this is incorrect. Well maybe it's possible it's correct, but it is in opposition to the Theory of General Relativity.


Actually this is agreeing with GR and much else in physics. From outside of a reference frame, an object of mass m1 will always have a gravitational field g1 when viewed from another frame of reference, regardless of changes in density in the other frame.

At relativistic velocity you get all of the effects that come with it, including added mass,


Not in this case, as we are shedding mass in EM radiation at the same rate that acceleration is increasing mass to keep the overall mass the same.

Why not just make it easy. Pick a neutron star that is already at the exact threshold of becoming a black hole, its velocity relative to you 0. Now start moving.

But just because it is more massive and dense when viewed from your frame doesn't mean it is more massive and dense in it's own reference frame.


Quantum effects would cause such an object to collapse into a black hole anyway. I have that sneaky feeling that at such a point that a velocity v can be reached from which the neutron star would appear to be a black hole, that the neutron star would have already collapsed to a black hole due to quantum effects.
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No a thought experiment it does not need to be done in real-life for example even Theory of Relativity was first only thought experiments which could not be proven until the Eclipse even then there was a row whether he was right or wrong so imagine we already accelerated it to that speed.
So first assume its reached that speed.

We are not breaking any physics that I know off.

Not in this case, as we are shedding mass in EM radiation at the same rate that acceleration is increasing mass to keep the overall mass the same.

Ahh. Sorry I guess I was on another page than you guys.

I think that concept introduces quite a paradox though.

I'm not sure that the shedding energy as fast as you gain it will work even as a thought experiment. It might be like losing money as fast as you gain it, while simultaneously increasing your total amount of money. It might be like starting off the thought experiment with the assumption that true = false.
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I'm not sure that the shedding energy as fast as you gain it will work even as a thought experiment


It should work, since the EM radiation would be going away at the speed of light out of the reference frame. Essentially, the Earth could be made entirely of radioactive material that decays appropriately to match the rate of acceleration. The odds of getting decays to match up like this are extremely extremely unlikely (they would not happen, but could happen, without breaking any laws of physics.
The only problem is how to accelerate the system?

No a thought experiment it does not need to be done in real-life for example even Theory of Relativity was first only thought experiments which could not be proven until the Eclipse even then there was a row whether he was right or wrong


Don't forget that the corrections to Mercury's orbit had already been found to be correct before the eclipse expeditions. I don't think there were many rows about if this was correct, only extreme doubt because it's totally totally crazy to say time & space are not absolute values.

No a thought experiment it does not need to be done in real-life for example even Theory of Relativity was first only thought experiments


No, it does not need to be actually done in real life, but it does need to not break laws of physics. You still have not said how you can accelerate something to such a speed that it causes a contraction of space-time as much as you require (without breaking known laws of physics)?
Okay, what about that it uses magnetic fields like a High Energy Proton collisions that happen in LHC. That being said it is possible without breaking any laws of physics.
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Okay, what about that it uses magnetic fields like a High Energy Proton collisions that happen in LHC. That being said it is possible without breaking any laws of physics.


How are you powering these magnets?
You answered it slighly anyway, powering

I'd be powering it using Electricity.
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Going back to an earlier part of thread, consider that we may be making false assumptions about what Back Holes are.

No Event Horizons

Now Hawking is suggesting a resolution to the paradox: Black holes do not possess event horizons after all, so they do not destroy information.

"The absence of event horizons means that there are no black holes, in the sense of regimes from which light can't escape," Hawking wrote in a paper he posted online on January 22. The paper was based on a talk he gave last August at a workshop at the Kavli Institute for Theoretical Physics in Santa Barbara, California.

Instead, Hawking proposes that black holes possess "apparent horizons" that only temporarily entrap matter and energy that can eventually reemerge as radiation. This outgoing radiation possesses all the original information about what fell into the black hole, although in radically different form. Since the outgoing information is scrambled, Hawking writes, there's no practical way to reconstruct anything that fell in based on what comes out. The scrambling occurs because the apparent horizon is chaotic in nature, kind of like weather on Earth.

We can't reconstruct what an object that fell into a black hole was like based on information leaking from it, Hawking writes, just as "one can't predict the weather more than a few days in advance."


http://news.nationalgeographic.com/news/2014/01/140127-black-hole-stephen-hawking-firewall-space-astronomy/

And consider that our understanding of Black Holes is vastly incomplete and potentially almost completely wrong.

This makes your thought experiment very difficult because we don't really even know what a Black Hole is let alone what a "pseudo-black hole" would be.
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This makes your thought experiment very difficult because we don't really even know what a Black Hole is let alone what a "pseudo-black hole" would be.


This is not squabble about what a black hole is, but what happens to matter that goes into it. The black hole still exists and still has an area proportional to entropy. It still has gravity too strong for light to escape.

The argument here is what happens at the event horizon to entangled particles (which may effect what can happen to other particles). However, quantum entanglement is poorly understood, as are black holes. It's no surprise this is not understood. A quantized theory of gravity, to replace general relativity, is probably required to resolve this. No easy task. Still, we may take a tiny step closer to that in 2015 when the LHC energies increase. It should rule out or confirm some ideas that can affect what quantized theories of gravity are and are not allowed to have.

You answered it slighly anyway, powering

I'd be powering it using Electricity.


hmm I tried using Wolfram's relativistic KE calculator to find out how much energy an electron needs to actually have to reach black hole density, but it gave infinity as an answer. lol
I'll try and find the maths (a calculator that doesn't show infinity) to show exactly how much energy you need to give something to black hole-ify it simply by acceleration. It's truly ridiculous...
The argument here is what happens at the event horizon to entangled particles (which may effect what can happen to other particles). However, quantum entanglement is poorly understood, as are black holes. It's no surprise this is not understood. A quantized theory of gravity, to replace general relativity, is probably required to resolve this. No easy task. Still, we may take a tiny step closer to that in 2015 when the LHC energies increase. It should rule out or confirm some ideas that can affect what quantized theories of gravity are and are not allowed to have.

Yeah but the point is that leading physicists in the subject of Black Holes are saying that event horizons don't exist, i.e. light does escape.
We know light does (eventually) escape since the 1970s. . . The point is that once it has passed the horizon, information about its past (before crossing the horizon) is lost and that is not under dispute.
The word "lost" is not a correct term to use here, its simply remitted as different radiation which is impossible to reconstruct the original one as its to badly changed.
Lost is how Susskind described it in lectures, so I think the word is just fine.
Well, I think you should have added double-quotes to it atleast lol

Anyway htirwin was right I should choose something more better than a blackhole. Would it however increase in gravity due to contraction as mass would be more dense.
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Anyway htirwin was right I should choose something more better than a blackhole. Would it however increase in gravity due to contraction as mass would be more dense.


No, most definitely definitely not. The gravitational field strength will remain the same. If you are an observer outside of the frame, you will measure no difference in gravity, no matter what the density. When the remainder of a super-massive star collapses, there is no increase in gravity when it becomes a black hole. If you stood some distance away from two orbiting neutron stars that then merged to become a black hole (let's assume there is no huge gamma ray burst when they do this, as this decreases overall mass. It's some kind of perfect merger where all mass stays in the system), you would not find any increase in your gravity.

The only reason a black hole appears to have such powerful gravity is that you can get much closer to the centre of mass, without going inside the mass. If you stand at surface of the sun, or the same distance away from a sun size black hole, there is no difference in gravitational field strength.
I thought there would be for example a neutron star is smaller than say a city yet it weights more than the sun, its because the material to extremely dense thus iits gravity increase due to more concentration in the fabric of space.
I thought there would be for example a neutron star is smaller than say a city yet it weights more than the sun, its because the material to extremely dense thus iits gravity increase due to more concentration in the fabric of space.


Gravitational field strength depends only on mass and distance, not at all on density. You can consider any object you're not actually inside of to be a point mass and you will get the same answers. In your neutron star example, the neutron star maybe has more mass than the sun and thus, stronger gravity. You can also get a lot closer to the centre of mass of a neutron star, so even if it has the same mass, you can get a lot closer in terms of distance.
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okay, thanks so clear this up for me plz

so because mass is more compact and closer and closer packed the observer as he gets closer is being pulled in stronger because there is more mass packed nearer and nearer to the point.
You can just look at Newton's law of gravity to see why this is (don't even need GR for this one).

F = G (m1m2 / r2)

As you can see, no mention of density here (nor in GR). However, we are diving by a radius squared! Obviously, if that radius becomes very small, the force becomes very strong. With an object like the sun, you can't get any closer than the radius of the sun (700 000km), because when you enter the sun, you then have some mass behind you pulling the other way, so the overall force becomes less. If however, the sun was compressed to say, 10 000km and you stood on that surface, you would feel a much greater gravitational force.

Force on a 1kg object at sun's surface (using some slightly rounded figures):

F = 6.67 * 10-11 * (1.989 × 1030 * 1 / 695 500 0002) = 274.3N

Force on a 1kg object at sun's surface, if the sun had radius of only 10 000km (using the same rounded figures):

F = 6.67 * 10-11 * (1.989 × 1030 * 1 / 10 000 0002 = 1.33 * 10 ^ 12N

Quite an increase!

Take note that in this second example, if you stood 695 500km away from the now much denser sun, you would still experience the 274.3N force.
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