The Worldwide General News (WGN) TV channel was inundated with questions about the danger from the LHC which was commissioned. They decided to devote their next ‘Space Talk’ program to this subject. For the purpose, they invited Albert Burman and Kalpa, the experts to their Studio.
On the appointed day and hour, Larry Newton the presenter of the show appeared on the screen. “Good Evening viewers. I am happy to welcome our distinguished guests Albert and Kalpa for the show to our studio today. Let me begin with a short introduction about them. Albert and Kalpa are space beings written about in the Science Fiction book ‘Alien Man.’ They have explored the satellites of Saturn and discovered Steel, Gold and Plutonium! Albert and Kalpa share their experiences in space on TV from time to time. They are well known all over the World as Space Celebrities. Welcome to you both!” Larry began the session. He continued after a short pause, “The subject of our discussion is the danger of extinction from the Large Hadron Collider (LHC), the World’s largest and the most powerful particle accelerator. Our channel has received hundreds of messages mainly about the possibility of the Collider destroying the entire planet by converting it into a black hole. We want our viewers to hear your analysis on this subject.” Larry opened the topic for the day.
“Good Evening Larry. We are happy to be here with you today to enlighten all of you about black holes which might emerge from the LHC. At the outset I want to allay all your fears and assure you all that the LHC functioning will not result in the destruction of our beloved planet Earth.” Albert gave his unconditional assurance to the viewers.
“Albert is absolutely right. All fears that the black hole generated by the Collider will eat up the Earth are based on misinformation and have no scientific foundation.” Kalpa endorsed the assurance given by Albert.
“But the Collider will form the black hole. Isn’t that correct?” Larry asked pointedly.
“We don’t know for sure, the scientists are saying that it is highly improbable. But I sincerely hope that a black hole does form. It will advance our knowledge about the fundamental forces in the Universe.” Said Albert.
“But once the black hole is formed, however minute, it will gobble up matter and grow and grow till the whole Earth becomes a black hole. This is what people fear.” Said Larry.
“This fear has arisen out the simplistic view that the black holes that are formed when a star collapses into a dense ball which pulls everything inside and not even light can escape it. This was the view at the very beginning when scientists discovered the black hole in the Universe. But since then science has progressed further and we now have a far greater understanding of the properties of the black hole. It follows the same basic laws of gravity as other objects in space.” Kalpa put the knowledge of black holes in the right perspective.
“What is the power of its tremendous gravitational pull?” Larry asked.
“The gravitational force that a black hole exerts on another body depends on only 2 factors: mass and distance between them. The more the mass of the black hole the greater is its gravity, and conversely, the smaller is its mass, the smaller is its pull. Similarly, the closer the center-to-center distance between the black hole and the object, the stronger is the pull between them. In fact pull increases exponentially as the distance reduces. The actual gravitation attraction between the 2 bodies is dependent on the product of their masses, and is inversely proportional to the square of the distance between them.” Kalpa explained the basic theory.
“The black Hole does not have a unilateral force pulling the object. The black hole itself can be pulled by the gravity of other more massive objects. In the case of the LHC, if the black hole is formed, it will be hardly be made of 100 protons and will be very small indeed. In absolute terms is that the mass of the black hole will be one hundred times the mass of a single proton, about 100 x 16 E-26 kg. If you divide 1 kg. into 10 raised to 26 parts (1 followed by 26 zeros) and take just 16 of them you will get the mass of the black hole. As against that, the mass of the Earth is 6 E24 kg, which means 6 followed by 24 zeros, in kg units. This shows that the Earth is so much larger than the incumbent black hole by a factor of 10 raised to 50! (1 followed by 50 zeros). The difference is stupendous! The small mass of the black hole is truly insignificant as compared to Earth, and consequently it will be pulled by the Earth rather than vice-a-versa.” Albert explained the relative size of the black hole.
“But since it is a black hole, its size will be less than a millionth of that of the 100 protons! It’s so small that it can penetrate everything and anything. It will be pulled by Earth’s gravity and will travel through to the Earth accelerating with its gravity till it reaches the centre of the Earth and the decelerating as it goes out on the other side, to be pulled back in again. It will swing back and forth like a pendulum!” explained Albert.
“No hope of that! The black hole will just evaporate in a fraction of a nanosecond! Stephan Hawkings of the Cambridge University says that the black hole creates new energy particles on its surface which escape. This results in shrinking the black hole. He calls it ‘evaporation.’ He says the smaller the black hole the hotter it is and the faster is the rate of evaporation! I do not know why he looks at the black hole as a liquid which evaporates. I would rather look at the black hole as a solid which sublimes. But no matter how you describe it, the fact is that a small black hole of a few protons mass will evaporate and disappear faster than we can measure the time!” Kalpa explained why the black hole will not last.
“A black hole is made of very dense matter. Our Sun for instance, with its diameter of 1.4 million kilometers will shrink in size to just about 4 km to convert to a black hole. But its mass will be the same, and its gravity will remain the same. If the Sun becomes a black hole, it will not change any of the orbits of its planets in the Solar System. It will not pull the Earth and gobble it up.” Albert outlined the limitation of the black hole.
“If this is so then why do the scientists describe the black star with as a region of space with tremendous gravity forceful enough to prevent even light from escaping!” asked Larry.
“This is because for a given mass, an object can go much closer to the centre of the black hole than a star or a planet of the same mass. For example the radius of the sun is about 700,000 km. An object close to the Sun is stopped by its surface which is 700,000 km from its centre. But if the Sun converts itself to a black hole of 4km diameter, an object can go as near as 2km. from its centre. Since the distance from such a heavy mass is now reduced so drastically, that the gravity just near the centre increases by 700,000 x 700,000 = 490 billion times! But the effect of this incredible gravity is felt only in a region very close to the black hole. Such close distances are not achieved in a normal object like a star or a planet due to limitations of its comparatively large size. The difference in gravity vanishes as the object moves beyond a certain distance. Further away from a distance equal to the radius of normal star of the same mass, there is no difference in the gravity of the black hole and the star.” Kalpa was clear in her thinking.
“What you are saying is that the black hole can only stop light in a certain range beyond which it has no effect.” Larry summarized.
“That is correct. If the black holes could suck everything from everywhere, and prevent light from transmission, how could see the billions of stars in the sky? Their light could have vanished in the black holes!” said Albert.
“In the case of our LHC, the black hole generated will be of the size of about 100 protons. The protons will form into a ball and shrink about one millionth of their normal size. The diameter of a proton in units of a meter, is 10 raised to minus 15 (1 divided by 10 followed by 15 zeros). The diameter of the black hole is likely to be one ten-thousandth of this value. And the extraordinary gravity that the black hole can exert is only with a range of say 10 raised to minus 18meter; which is a billion-billionth part of a meter! There is no possibility that any matter in the form of any protons or atomic nuclei coming so close to the minute black hole ball particularly in the extremely short duration of its existence. So for all practical purposes, there is no scope of the black hole expanding if at all it is formed.” Asserted Kalpa.
“There is another argument put forth by Steve Giddings of the University of California (Santa Barbara) and Michelangelo Mangano of LHC’s parent lab CERN. They point out that there are minute black holes being generated by cosmic rays hitting a neutron star, But these microsized black holes do not seem to grow inside the body of the star which is more than a trillion times denser than the rocks on Earth. From the observations made of the cosmos, the scientists infer that as black holes do not exist inside dense stars, they couldn’t exist inside the body of the Earth. And in case the black hole does exist it will probably take a billion years to grow to the size of a golf ball! They conclude therefore that there is no danger of the small black hole from snowballing into an Earth gobbler.” Albert brought out an authority on the subject.
“Anyway, coming back to our topic, whether the LHC will create a black hole which will destroy the Earth, the answer is an unequivocal ‘NO’! The LHC was switched on the 10th September but only for checking the functioning of the beams. There was no collision attempted. Now it is down for repairs and will be ready early in 2009. But rest assured that there is nothing going to happen to the Earth and to you when the LHC is switched on and the particle beams are made to colloid face to face at 99.9999% of the speed of light! No fears!” Albert spoke emphatically as Kalpa nodded in agreement.
“I am happy to hear that. To be frank, I was fretting too. But now I am fully relaxed. I have to thank you Albert and Kalpa for explaining the concept in simple language for the benefit of our viewers. The back office has informed me that their phone is constantly ringing with viewers giving appreciative thanks to you both. Now we can all sleep peacefully. Thank you again.” Larry wound up the discussion.
And with that the Space Talk show ended.