Black Patches In Stool

50 solutions to the Fermi Paradox (30 th solution): There are plenty of CETs, but only within each particle horizon

The biggest proponent of this solution to the Fermi paradox is Michael Hart. To fully appreciate your argument we should understand the concept of particle horizon .

The easiest way to explain it is to assume that the universe is static. Obviously, we know that this is not true, our universe is continually expanding generating more and more space, but anyway, this expansion does not invalidate the reasoning Hart.

Imagine, then, an infinite universe in which galaxies are distributed uniformly, as more or less observe today, slightly less than 14,000 million years after the Big Bang. Surprisingly, the sky does not appear dazzlingly awash with light from the endless galaxies (remember the Olbers paradox). The key lies in the finiteness of the speed of light, so that no signal or influence may have reached us from regions beyond about 14,000 million light years. This distance marks the particle horizon and is the effective size of the observable universe . Nothing is beyond the horizon has had time to reach the observer. Hart

reasoning as follows: First, suppose that the universe is infinite. Since its inception took place some 14,000 million years, the size of the observable universe is given by the distance to the particle horizon. Second, suppose that biogenesis (the development of life from inorganic molecules) is extremely rare (many biologists believe otherwise, but our knowledge of the subject is not too deep). It follows, therefore, that in an infinite universe there will be an equally infinite number of planets with life, but whose respective particle horizons there is only one planet with life.

As Hart notes, the idea can be easily distorted. For example, aliens may visit Earth, or SETI could succeed and signs, or astrobiologists could prove that life spontaneously arose on Mars, regardless of the Earth. However, in the absence of previous evidence, Hart argues that the Fermi paradox leads to a chilling conclusion: we are the only civilization within our own particle horizon. Although the universe contains an infinite number of advanced civilizations, for all purposes, we are alone ...

Sugar Glider Ovulating

Indiana Jones, his big balls, fucking inclines and the odd potato more ...

The year is 1936. Professor of Archaeology Henry W. Jones Jr., better known as Indiana Jones, is facing the dangers of the jungle in Peru, with the intention of recovering the golden idol of Hovitos of an ancient temple, which is accessed through a cave in the mountain .

After surviving a terrible trap, "Indy" is finally appreciated treasure on an altar. Replacing it with a bag full of sand (mentally calculated the weight of the statue, as compared with the bag and convinces him not decide to eliminate some of the sand) to prevent the dangerous consequences of a mechanism connected, the intrepid archaeologist has to leave the temple with the figurine in his hands. Too late. The altar is sinking under the weight of the sand and an immediate storm of darts and arrows of all kinds are unleashed on the spot.

Surely the fictitious tribe of Hovitos to that in the movie referred to under the preceding paragraphs, Indiana Jones in Raiders of the Lost Ark ( Raiders of the Lost Ark , 1981), is based in real the Chachapoyas (my sincere apologies for the painful cacophony) that inhabited the Andean region of Amazonas, northern Peru. The Andes Mountains are the highest in the world, excluding the Himalaya, and that's why the Chachapoyas were known under the name of "warriors the clouds ", as it was believed that reached to touch with their own hands.

Before the English arrived in Peru in the sixteenth century, the Incas had conquered the Chachapoyas. The capital of Cuzco and the Inca empire was in the center of this city, was a great temple dedicated to the Sun, known as "Koricancha" which means "gold store, where they kept many sacred idols made of the most coveted of precious metals.

Cabe, also the possibility that the temple of the Hovitos is inspired by the ancient temple of Cuélap Chachapoyas, 600 meters long and located at 3,000 meters altitude. To get there, people should row to climb a a narrow passage of more than 30 meters long, with walls sloping inward designed to defend against attacks Incas.

After stealing and seize the golden idol of Hovitos, Indiana Jones flees the temple. When he thinks he's safe, suddenly, a huge round rock can be seen from the top of a ramp and starts rolling menacingly down the narrow passage by which shoots our most intrepid archaeologist. Legs giving everything your pants let Emidio Tucci, Indy manages to reach the exit safely.

Stop, stop, stop. Stop the ball for a moment. Well, any questions? Yeah, well, the truth is that I can think of a few, but just be raising three:

1 .- A handful of sand to replace a statue of solid gold?

2 .- Are there any giant boulders perfectly spherical?

3 .- Why can not afford the huge stone, with "all the momentum" that carries with it?

Now, begin with the first, continue with the second and end up finally trying to sow discord because of the third. Incidentally, this last question has a very curious story. I tell it briefly. I guess to remember that a couple of months I taught in Seville a lecture entitled "Einstein vs . Predator: Some things you always wanted to know about physics and you never dared to ask " (I remind you that you can see it in HD here .) Well, remember when was the turn of questions (I had it so good in a long time) someone in the audience (an archeology student, if memory serves me) made me a very similar question, ie, Indiana Jones does not succumb crushed by the rock that if it had pursued an "inertia" huge (you can listen to my crazy response in the video). Few days ago I went to my desk in college and start thinking about bullshit I missed the train, so I said: as much as run it not, because the train has more "inertia" than you. Then I remembered the question of the boy and returned to tell me once more, but what does inertia or inertia, if inertia has nothing to do with this case, if the train is not reached because it is "enchufao" to cables and I have to use the feet bare, with the shit I endilgao breakfast this morning, I did not even reach 30 meters to gauge. And this is the sad story behind this cachondona entry, so I've told you as closely as I could and promptly pass and to answer the questions previously raised.

start with the golden idol and the bag of beach sand. If I forget for a moment the key question, that is, how on Earth do Indiana Jones carries a bag full of beach sand in the bag? and I focus on having a scientific interest, ie to what extent it might be wise to replace a solid gold statue of a bag full of sand? then things change a lot. Now, by the relative size of the idol in the hands of Indy, we can estimate that has a size not exceeding 20 inches in height and 10 centimeters wide. If we model like a cylinder, calculate the volume and multiply by the density of gold (19.3 times that of water) we get that the mass of that not inconsiderable amounts to about 30 kilograms. Doctor Jones, would have been better to carry a sack of potatoes and have removed a couple of them in the manner of man at the grocery store on the corner, do not you think? Great! First question answered. Now for you to justify it, as always, that if the statue is not solid, if you only have a swim in 18-carat gold and other foolish nonsense. Okay, okay, I know them all. A scratch it! I go ahead with the second question. Great

spherical rocks lie Koekohe on the beach (rocks Moeraki ) on the coast of Otago (New Zealand). Local legends claim that comes from potatoes and pumpkins as vases kumaras formerly employed. There are up to 3 meters in diameter. On the beach at Hokianga, North Island, also in New Zealand, can be found Koutu rocks, some over 3 feet in diameter. Katikies Rocks, 20 miles south of Moeraki are also completely round.

In North Dakota may be spherical boulders up to 4 meters in diameter. In Wyoming, Kansas and Utah are 6 meters. Finally, in Peru, the jungles surrounding Cuzco and Machu Picchu, spherical boulders lying in the beds of rivers and streams. Here, one point for the writers, who should not be too cruel. What is tricky now, I go with the third and last of the issues which arose during my lecture in Seville.

One of the topics that my effort is devoted to them in college students is the rotational dynamics of rigid bodies, for that rotation to sound like them round and round and in such case only understand weekends. The case is one of the exercises in class that I propose has to do precisely with the particular case of Indiana Jones. I tell you as briefly (jijiji. ..) I can. Physicists call

a rigid deformable body, in which the distance between two points on the same always remains constant, whatever the force applied to it. In the most basic educational levels, the bodies are considered point particles, ie have no size. Thus, when moving only have what we call translational kinetic energy, because a particle can never describe a rotation around itself. Instead, when you want to describe the motion of a body in a more rigorous, it is essential to consider as particular geometry and size. In this case one can show that the move has two types of kinetic energy, a translation and a rotation. Well, now let one of these rigid bodies rolling from the top of a ramp in which, for simplicity, we will not consider the effect of friction. Without wishing to dwell on the details (they have to deal with my students, that's what they are) the exercise I propose in the classroom is basically that I prove that when the top of the ramp located bodies of different geometries (a ring , a hollow cylinder, a solid cylinder, a hollow sphere and a solid) with speeds reaching no lower plate depend either on the mass and size of bodies, but only on the height from which they were released (the same for everyone) and the particular type of body concerned.

What does all this? Very simple. All you have gravitational potential energy at the top of the ramp turns into kinetic energy, both translational and rotational as they descend, ie consumed in lower part and spin part. Thus, it is not too difficult (not sure my students will agree with this statement) that the order of arrival of the different bodies is as follows: first the solid sphere, then the solid cylinder, hollow sphere and then, finally, the ring and the hollow cylinder, both at the same time. Moreover, if we proceeded to launch only a single class bodies (all solid areas, for example) but of different weights or sizes, all had come at once, regardless of even their different "inertia" (wink, wink and wink). As you can see, the Hollywood writers here have earned another point in its favor, as they have chosen the body faster to threaten all Indiana Jones.

Another conclusion that can be extracted after calculating the rate of arrival of the different solids at the end of the ramp is that it is in all cases lower than that reached in case of being left to fall freely from the same height. Obviously, if we considered the friction with the surface of "puto inclined plane, the situation would be even more favorable for Dr. Jones.

Finally, I will provide some numbers that you can judge the plausibility of the scene shown in the video. If my students have successfully solved the problem, will come to an expression that says that the speed with which it reaches the end of the ramp the solid sphere (the size you have, that is absolutely irrelevant) is 3.74 times the square root of its height. In the film, this point does not seem to be much higher than about twice the height of Indiana Jones. Say in round numbers about 4 meters, which gives a velocity of the sphere of 7.5 meters per second or, equivalently, about 27 km / h. Judge for yourselves if you would be able to run at this speed while I cagáis pants. And is that inertia, wherever it comes, it's scary, very scary. And the archaeologist, his ball ...

GLOSSARY (for people with limited English vocabulary of pure strain):

poya : Right to be paid in bread or money in the oven. Sounds like "cock", which means penis. Emidio Tucci

: Tailor of El Corte Ingles.

enchufao : plugged in, connected.

feet bare, feet, hooves.

foist : get under his belt. Eat, devour.

gauge: which run swift and speedy greyhound fearless.

inertia : ????????? Often accompanied by adjectives such as "much" or "great."

Sources:

Why which had to be snakes? The mysteries of Indiana Jones . Lois H. Gresh and Robert Weinberg . Robinbook . 2008.

My fucking brain, Sergio L. Palacios (Ph. D.), Journal of Mental intelects Tara and absolutely superior, Vol 69, p. 69-96. November 2010.

Curtains Black Silver

50 solutions to the Fermi Paradox (29 th solution): The cloudy skies are common

Nightfall (Nightfall , 1941) is a short story by Isaac Asimov. Considered one of the best in the history of the genre of science fiction, tells the story scientists on the planet Lagash, belonging to a solar system consisting of six stars. Physicists of the world impossible to have recently discovered the law of universal gravitation and she is able to predict the position of any of its six suns, and deduce the existence of a moon that orbits of Lagash. Obviously, this is not visible in the sky because of the eternal light that bathes the entire planet. Asimov

masterfully tells what happens in Lagash when an unusual alignment of the six suns and the moon and an eclipse lagashianos provide, for the first time, the night sky.

astronomers a world it would find it extremely difficult to develop what we call astronomy. Because of its six stars light permanently hidden other celestial bodies, would not know about the existence of other celestial bodies, they could not find other planets and stars. Historically, on Earth, the development of physics has depended critically on whether they tried to explain the orbits of other planets. How have done it without a clear view of the night sky? Lagashiana civilizations as may be superior to ours, have developed much more advanced technologies, but may not even try to contact us because simply would have no idea of \u200b\u200bour existence.

Although the situation described by Asimov is highly unlikely, we can think of many other cases where the physical conditions of an alien civilization could prevent the development of the notion of the existence of intelligent beings on other worlds. What if the planets were common covered with thick clouds? Maybe out there there are thousands of CETs but locked under dense cloudy atmosphere or, alternatively, very close to the galactic centers, where the sky lights up permanently, or in any other planetary environment that could present insurmountable difficulties for astronomy. "It would explain that the Fermi paradox ? Is it conceivable that the Earth is the only planet with the possibility of clear skies?