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Egon the rabbit and me: The wonder of finding an invisible planet (3)

Part 3

I: We could continue the story about cage. I actually think thorough it. However, I haven't had a clear idea on it yet. I would like to back to the story about finding invisible planet. How the wonder changes to a great thing.

Egon: ...

I: A person found the ``Things fall down'' and ``how the planets move'' are based on the same rule. People calculate the orbit of planets, they found every planet follows the rule. Someone found a new dwarf planet by a telescope, it also followed the rule. At least people could not find a planet that doesn't follow the rule in the solar system. When a better telescope was created, the telescope found a new planet, still the planet follows the rule. People started believing ``Things fall down in the universe.''

Egon: You, or human being observes the universe and found the same rule many times. No exception could be found.

I: Actually they found an exception. One planet doesn't follow the rule exactly. Its orbit was only slightly differs from the expected orbit, but still unexpected. People had two opinions for this. The first idea is the rule, the law of gravity, has something wrong. It maybe a good approximation, but not exactly correct.

Egon: ...

I: The second idea is we have an invisible planet somewhere, that causes this unexpected movement. The second idea still believes the law of gravity is correct, just we don't have enough knowledge of the solar system yet.

Egon: You believe the ``Things fall down'' rule, and tend to have the second idea. When everything is expected, you think your knowledge of the solar system is completed.

I: Yes. Maybe that is the reason I don't feel this is a magic. If we could not find the invisible planet as we computed, this is more big problem for me. Since the law of gravity doesn't work, ``Things doesn't fall down there.'' Things doesn't fall at somewhere, I could not believe that. So I rather believe there is an invisible planet. Then, people found the planet as they computed, this is no magic, but it is a great things. We maybe have some understanding of part of the universe. I still have a consistent world. That could be the foundation of the next understanding. Isn't it a great thing?

Egon: I'm not sure. You told me you don't know the origin of the gravity. You only know how it behave as a law. Your law of gravity could be a special case of more large law.  Then your friend may think, there could be a planet that doesn't follow the law of gravity. Because it is just a special case. It's great if you can fly around without wings. ``Things fall'' can be wrong at somewhere in the universe.

I: I cannot against that idea. I only know the law. It's like when I try to fix my program, I only know when I push this button, then the program crashes. But I don't know why, what did I wrong. I only know the push-this-button-crash-the-program as a law.  You might be right. But, the physicists observe the universe quite a lot and they now believe ``Things fall down in the universe.'' I also believe it. The law of preservation of energy, the law of inertial, and so on, are basically the same. Ultimately, we don't know why, but the observation are the same all the time, therefore, we call them ``a law.''  It is always so, I don't feel it's a magic.

Egon: Your friend might be a genus. Since she might think it is a magic.

I: By the way, one of my physics teacher asked me at one exam, ``Why the things fall?'' I answer, ``I don't know.'' The teacher said, ``Because there is the law of gravity.'' So, I understood this teacher doesn't know what the law of gravity means.

Egon: People tend to think if there is a name, they think they know it. First time we met, you ask to kids, ``What is this?'' ``It's  Egon the rabbit.'' ``I see.'' What did you see, really? What did you know about me?

I: I just know you have a name. I know nothing about you, of course. I lived in not my born place. Some people asked me, ``Where are you come from?'' I answered my born country's name. It is nice if the conversation expands, but, some people behave as they understand my personality and everything because where I was born. I know that's impossible. When I know you are a rabbit, how I could understand any of your personality? I know I just know you are a rabbit whose name is Egon.

Egon: OK.

I: ... I feel no magic on some preservation law. For me, something is gone, it means someone took it. Things don't magically disappear. If I keep some cookies at my home and one point they disappear, at that time, one of my friend visited my place. I don't eat that cookies, then?

Egon: You don't think your cookies walk away. You think your friend ate them.

I: Yes. There is the preservation law of cookies. The amount of cookies in my home are preserved unless someone ate them. I believe the preservation law of cookies. If I cannot see them, someone ate them. Even I didn't see who ate them, I believe someone must ate them. It's the same that a visible planet moves unexpected way, there must be an invisible planet.

Egon: You are old, you just forget you ate them. ``Things fall down.'' Your cookies may fall down under the table.

I: If I forget, well, still someone (which is me) ate them. So the cookies preservation law still hold. Under my table is still in my room. The cookies preservation law holds, either. This comes from Feynman 's ``Dennis the Menace'' story. This story is fantastic and ...

Egon: You believe in your small world. It sounds like against your learning story.

I: If I just believe it, I stay in my world. But, I will see outside based on my belief, and this is a difference from just staying my world. I always look outside based on my belief to expand my ``consistent'' world. I am standing inside my world, but, look at outside.

Egon: ...

I: When I found a case that doesn't hold the preservation law, I know I am on the edge of my world and I am facing the outside of my world. If I could not find my cookies, I could not find it in my room, friends were there but they didn't take them, I haven't eaten them either... But I found my room has more carbon dioxide than before and increasing the temperature a bit. Maybe my friend burned my cookies whatever the reason. These cookies are still in the room by the form of carbon dioxide gas. I need to expand my cookie preservation law. It looks no more cookies, but atoms are preserved. This is how science progress. To make my own world larger, I always need to find something wonder. When we understand them, we lost a wonder, but still we have a new great thing. This is one of my favorite part of science.

Egon: Then, you still believe the cookie preservation law holds in other houses on the earth. It's like a religion that you ``believe'' it.

I: I think science is a kind of religion. The dogma is ``human being can correctly understand a part of universe.'' But, we need facts that can be measured by machines. Someone said this is right doesn't matter in the science, we always need to reproduce the law independently. There is a small difference from many other religions.

He seems to lost the interest of the conversation with me. I explained the Feynman's ``Dennis the Menace'' story to him. But, Egon continues to eat leaves of carrots without any words.

Acknowledgments


Thanks for H.H. to give me the hint of this story. Thanks for my friends who discuss about the wonder with me. Thanks to my small students and also my small teachers who always gave me hints to re-think myself. I hope R.M. enjoy this story who inspire me a lot.

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