19th Oct, 2020

KU Leuven

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Question

Asked 13th Oct, 2020

If the Earth going through space would be close to a black hole, it would be gone to the center of it. Perhaps it is surrounded by low-density air

My questions are:

1. Could exist a black hole there without eating Earth surrounded perhaps by vacuum?

2. If it is possible that the black hole generates a lot of energy in the out border of the event horizon that could explain that the Earth heating is about twice the received sun power?

3. If it could explain the Earth magnetic field

4. It's mass

5. How to detect it

6. If it is true, perhaps earth temperature is higher than several million years before. It is known what was the Earth temperature then?

I make these questions because I am worried about the danger of generating a stable black hole in a scientific test. If one of them were created, it would go to the center of the Earth eating earth generating a thin tunnel.

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1) It is possible to orbit a black hole like any mass. A BH only "eats" when matter passes through its event horizon, so staying far enough away prevents this. The necessary speed of the orbit (distance r) about black hole (mass m) may be calculated through sqrt(G*m/r).

2) Earth heating is not from a black hole, it is from solar radiation and thermal energy stored beneath the surface. The latter is predominantly from radioactive decay, and to a lesser extent stored from Earth's origin I believe.

3) No. Magnetic fields are related to the motion of charged fluids. Though not fully understood, search "Earth's dynamo" for more information and the latest research, e.g:

4) Black hole masses may vary, and I believe evolve with time. For a black hole to form from a star, there is a minimum mass required which is known as the Chandrasekhar limit, approx 1.4 * mass of our Sun.

5) *N/A, there is no black hole in the Earth*

6) *N/A, there is no black hole in the Earth*

Note: I would not be worried about the generation of black holes on Earth. The masses/energies required are well beyond human capabilities, certainly in our lifetimes. Be worried about more immediate concerns, such as climate change or water scarcity!

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Respected sir,

I begin by answering your questions one by one. The answer to the first question is that if any object enters into the gravitational field of a black hole it will move in a specified trajectory getting nearer to the black hole every now and then.

Coming to your second question; the simple fact is that black holes release energy in very small quantity and if earth gets near the event horizon, earth will be burnt to ashes when it will hit the firewall present at the event horizon so there's no chance of black holes emitting heat twice as the sun does for us. I do not understand your third question so please pardon me. in the fourth question I assume that you are asking about the mass of the black hole. The mass of a black hole is calculated by the formula M_{BH}/M_{SUN} = (v_{sat}/v_{earth})^2 (r_{sat}/r_{earth}); where M_{BH} is mass of the black hole, M_{SUN} is mass of the sun, v_{sat }is the velocity of the satellite from which the black hole is being observed, v_{earth }is velocity of earth and r_{sat }and r_{earth }is the radius of the satellite and the earth, respectively. It can be detected by the photon ring at the event horizon and there are indeed some other procedures but currently I am unable to recall them. I hope that yo last question is related to global warming on earth which has cause rise in earth's temperature. So after making this assumption I can say that before humans were able to practice farming and developed agricultural techniques earth had an optimum temperature of about 17 degree Celsius.

I would like to mention that if you are afraid of creating a small black hole in a scientific test then I don't think it will survive more than 1 second. But then also if you can approximate the mass of the black hole which you fear can be formed in the experiment then you can calculate many of its properties from this site: https://www.vttoth.com/CMS/physics-notes/311-hawking-radiation-calculator .

I hope that my answer has provided a solution to your question.

Yours Sincerely,

Rishi Raj

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Sorry, I said that the Earth surface emits double the energy received by the sun (I read that some time ago). I wrote about a black hole very very small with a mass much less than 1/1000 of the earth (if not it would be detected). As long as you said the black holes emit low energy levels the question is answered: it does not exist such a black hole. I will use the hawking calculator to see that.

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14th Oct, 2020

Horst Stöcker has a patent for converting mass into energy with mini black holes. The idea is to collide normal matter, e.g. from the garbage bin, with a mini black hole. The Hawking radiation that comes out can be used as a heat source.

Mini black holes can be manipulated (fixed, accelerated) with electric fields, if charged.

Regards,

Joachim

2 Recommendations

I agree with dear Joachim Pimiskern

If we recall the TOKOMAK project, then a black hole can be artificially created. Skeptics see this **end of the world**.

Regards, Sergey Viktorovich Pushkin

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The Tokamak cant creates black holes because the pressure and energy density are too low. Perhaps the Collider has enough energy density.

There is another energy source: matter can compress and fuse generating a lot of energy before being included in the BH

Using the calculator the black hole diameter for a BH 1/10 earth it would be 1.77 m in radius, I think it is impossible to generate so much energy in so low diameter without evaporating all around it and eating it in microseconds.

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A black hole can increase the pressure over 1000 megabars that is needed for fusion, so a lot of heat would be created. It would be needed what is the distance of a black hole of 1/10 to 1/100 of earth mass to reach 1000 megabars and look if enough energy can be generated to heat Earth surface to 17º, accordingly Rishi Raj . Then the black hole not would eat everything as long as all space between the fuel and the BH would be fully ionized by so intense radiation, so it would reflect all the electromagnetic energy, and perhaps matter.

The only problem is that BH half-life is one second unless it is regenerated again and again, like a hearth.

Sorry, could somebody explain why a Black Hole os 1/10 Earth mass (6e23kg) calculated using the calculator ( https://www.vttoth.com/CMS/physics-notes/311-hawking-radiation-calculator ) emits so low energy and is evaporated in a few seconds?. Accordingly that the energy at the BH is mc^2, which is large enough to destroy all the Sun planetary system if evaporated in 1.4 seconds, but Hawkins energy is 2.5e-76 watts only. Somebody must made a mistake

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@Javier Luis López, you nedd to find the Schwarzschild Radius of the earth in order to find aboit the nature of a black hole whose mass is equivalent to the mass of earth. It turns out that the Schwarzschild radius for a black hole with mass equal to that of earth is 8.87×10^−3 m and its hawking temperature is 0.0205415 K and its luminosity is 9.98369E-18 W and it evaporates quickly in 1.79237E58 seconds and this is the special property of black holes. The smaller the radius the faster it evaporates and if a black hole has its Schwarzschild radius equivalent to the radius of earth then its temperature is 2.86020E-11K and its lifetime is 2.10391E77 years. The problem with the calculator is that we need to adjust our units with respect to the data we enter there. If we are chosing solar mass then we need to take lifetime in the unit years.

I hope that this solves your doubt.

So if the disintegration of a BH of 6e23kg generates 9.98e-18 watts during 1.8 seconds that is 17.96e-18 Joules, you should need 17.9e-18 joules to compress the earth in a BH of 8.87 millimeters....are you sure? Not use QM only, accordingly Newton, a simple m*g*h account gives different magnitudes order, but in the exponential part.

BH does not disintegrate and they are really dangerous so must be taken into account seriously

The luminosity generated by the disintegrating BH of mass 6e23 kg is just 9.98*10^-18 watts and when we write it in decimal notation it turns out to be 0.00000000000000000998 watts which is very small. Similarly the energy is also very low and it is just 17.96 × 10^-18 joules. (equivalent to 0.00000000000000001796 joules in decimal notation.) And this is the case when the BH collapse when time is defined by t_{collapse} and there is burst of hawking radiation. The gravitational collapse of a body is only possible when, after the collapse, its time extend up to future infinity and space is compressed into a singularity. For a body like earth, we can find out the Schwarzschild Radius by using the formula R=2GM/c^{2} and this can say gives us the measure of the event horizon of the BH (as when this radius is equal to 0 then we say it is a singularity and the above conditions are satisfied). This is a much more geometric picture and says that collapse of a body to a BH is only possible when it continues to shrink under its own gravity unless its time is extended to future infinity and space is bent to a singularity. That's the reason why we need to make the earth smaller in size to make it a BH and not to apply an energy of 17.96 × 10^-18 to make it a BH.

Now coming upon the disintegration in black holes. As far as I know and as I had mentioned in my earlier answer also that "*smaller the black hole, the high is its radiation". *This is why a BH of size 8.87 mm will radiate quickly and the information stored at its singularity is probably lost. (I don't know so far that anyone has provided a complete answer to the Information Loss Paradox in Black Holes) That's why disintegration is possible for the black hole but not for its singularity. This causes loss of information, as an observer can no longer see the event horizon of the BH after the evaporation of the particular black hole. Also it is to be noted that the BH's singularity has infinite curvature and gravity and cannot go to collapse further.

1 Recommendation

17th Oct, 2020

No singularity, No Big Bang, No Black Hole, No wormhole, No time traveling, No mechanical Gravity, No trampoline factor, No empty space, No mechanical energy, and No mechanics atom. All these are result of some "scientists " idea that they did not know anything about universe.

Our universe is a complete well organized , and the accurate entity that is working much precise than swiss watch.

Article How the Quantum Universe Works

regards

1 Recommendation

1) It is possible to orbit a black hole like any mass. A BH only "eats" when matter passes through its event horizon, so staying far enough away prevents this. The necessary speed of the orbit (distance r) about black hole (mass m) may be calculated through sqrt(G*m/r).

2) Earth heating is not from a black hole, it is from solar radiation and thermal energy stored beneath the surface. The latter is predominantly from radioactive decay, and to a lesser extent stored from Earth's origin I believe.

3) No. Magnetic fields are related to the motion of charged fluids. Though not fully understood, search "Earth's dynamo" for more information and the latest research, e.g:

4) Black hole masses may vary, and I believe evolve with time. For a black hole to form from a star, there is a minimum mass required which is known as the Chandrasekhar limit, approx 1.4 * mass of our Sun.

5) *N/A, there is no black hole in the Earth*

6) *N/A, there is no black hole in the Earth*

Note: I would not be worried about the generation of black holes on Earth. The masses/energies required are well beyond human capabilities, certainly in our lifetimes. Be worried about more immediate concerns, such as climate change or water scarcity!

1 Recommendation

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