The earth is obviously spherical, why is the ground flat?

It's just that the diameter of the earth is relatively large, so people can't feel the arc, and if you get to a high enough height or leave the earth, you can feel the arc.

The earth is about 40,000 kilometers in a circle, and even if it is a province, the ground is flat, and the diameter is only 1,000 kilometers, right?

A: Because the ground is a walking road, the ground is flat.

First of all, the curvature of space-time distortion just makes the earth form a circle of circles, in fact, absolute circles do not exist, our space-time relationship, so that many things present spheres and circles, but these spheres and circles, are not absolute circles or spheres, in the final analysis, because our space-time does not exist absolute cycle. Our light also runs along the curvature of this space-time, and we rely on the propagation of light when we observe, so when light approaches a sphere or a circle, the model in our brain naturally uses a circle to fit the world. However, our world is built on straight lines in distorted space-time, and the ground is flat because we see straight lines in curved curves when compared to a curved space as large as the Earth.

Similarly, on any object if you put it small enough, then you will find that no matter how sleek it is, it will eventually run in a straight line. Curves, however, are nothing more than an integral principle. Not equal to 1.

But when we do the calculation, for the convenience of the graph, we can make it equal to 1

Finally, in fact, the ground is not flat, our space is distorted, so if there is something absolutely flat, then this flatness must balance out the distortion of space-time, however, as the above example said, after zooming in, everything is a straight line, so the flat ground, after magnifying it, you will find the illusion of a flat surface composed of more uneven straight lines.

And magnification is not infinitely magnified, our observation relies on light, when we magnify to a small enough level, to the extent of photons, traditional mathematics is no longer able to cover this progression, wave-particle duality makes the world have a new perspective, for this reason, to introduce quantum mechanical algorithms, to help us calculate these microscopic worlds. The great thing about quantum mechanics is that it looks at it as a 1 to calculate. We've made it easier to calculate.

The earth is round, but people feel flat on the ground because human beings are very small compared to the earth. This arc can be considered invisible because everything seen is flat.

In this case, the ground as seen by one is flat, even though the entire earth is round. If you look at the Earth from space, you can clearly see that the Earth is round and is a sphere.

The earth is so big that it can be seen flat everywhere people can see it, and if you want to see the arc, it is a very difficult thing to do. But when you put people on a certain point on the surface of the earth, the place where you can see is nothing to the curvature of the earth, and the earth as you see it from that point is flat.

Because human height is disproportionate to the size of the earth, humans can only see a small part of the earth as far as the eye can see. Compared to the 100 million square kilometers of the earth's surface, this part as far as the eye can see is almost negligible. But for humanity, this part is already huge.

This is similar to the subdivision of derivatives in mathematics, a plane figure composed of an arc can be approximated as being composed of many rectangles, and the more subdivisions, the more accurate the area calculation. If you subdivide infinitely, the sum of the areas of all rectangles is equal to the area of the planar shape. It is precisely because of the small size and height of human beings that the ground is considered flat.

Flat or round, this is a matter of perspective. A long, long time ago, the round sky was still people's understanding of the world. With the development of the seafaring industry, one day it was discovered that ships would disappear from the sea level, and some people thought that the earth might not be square.

Standing on the seashore and looking at the sea-sky intersection in the distance, you can clearly feel that the earth is round, and you can see that the sea level is not horizontal, but arc-shaped.

In addition, in fact, from the moon or space satellites, you can clearly see that the earth is indeed round, in fact, the earth is not round, which has been introduced in the geography class of junior high school.

One might say that since the earth is round, there must be a very slight arc on the ground in theory and in practice, why can't the instrument measure this arc?

If it can't be measured, it can only be said that the method is wrong, or the accuracy of the instrument is not enough. The earth is simply too big for human beings. The volume is trillions of times that of human beings, and we can't see the whole plane of the earth as far as our eyes can see, and the places we can reach are nothing to the curvature of the earth, and the earth as we see it from this point is flat.

Therefore, due to the problem of perspective, ancient people have always believed that "the sky is round and the place is round", which is the limitation of knowledge and imagination.

Why is the earth round.

The reason why the earth is round is because the gravitational force of the earth itself has the characteristics of centripetal, so the shape of the isotope plane formed by the centripetal gravitational force will be a spherical shape, so the shape of the earth will be round, in fact, strictly speaking, the shape of the earth should be elliptical.

The shape of the earth is not a regular spherical shape, but an oval spherical shape that is more bulging than the two poles in the middle of the equator, and this shape is not regular, it is more like the shape of a round pear, so many times, people will also call the shape of the earth "pear-shaped".

As one of the eight planets in the solar system, the earth is the only planet with human activities and survival, and the distance between the earth and the sun is about 100 million kilometers. While rotating from west to east, the Earth also revolves around the Sun. The Earth we live on is now about 4.6 billion years old.

In the past, people did not know much about the shape of the earth, but most people believed that the earth was flat, because the ground was flat, so for a long time, the theory of the earth became a recognized concept, and later Pythagoras of ancient Greece put forward a new concept, he first put forward the theory that the earth is spherical.

。On an endless plain, or in the middle of an endless sea, you will see the horizon in the distance, and that is because the earth is round, you can only see that far, and the farther place is just below the sphere. There is a sailboat coming from the far side of the sea, and you will see the mast first, and then you will see the hull slowly, as if it is rising from under the sea, and this is because the sea level has an arc.

And the reason for the flat is because you are on this plane, and man is too small for the earth to feel the existence of a sphere.

We look at objects near and far, and there is such a huge difference between people and the earth, and if you are standing on the ground and looking at the earth, you can only see the infinite ground from your perspective. When people's perspectives are farther and farther away from the Earth, to the point where they can see the Earth from outer space, they can see that the Earth is a sphere. When I went to Dubai, I stood on the observation deck on the 124th floor of the Burj Khalifa, the world's tallest building, and looked out ahead, the houses under my feet had shrunk to models smaller than matchboxes, and the horizon could be faintly seen in the distance.

The earth is round, and the arc of the earth's huge sphere is almost negligible compared to the huge spherical surface of the earth, and it looks flat. Although it is difficult to find a large area of flat ground on land, and there are various ups and downs of landforms, it does not affect the ancients' belief that "the sky is round and the earth is round", and the range of people's activities on land is also very limited, and the world of understanding is centered on the ground, and we are completely unable to realize that we are living on an ellipsoidal planet.

Because the earth is too big! It is trillions of times larger than our individual human beings, and it is impossible for our eyes to see the entire planet. But when we are placed at a certain point on the surface of the earth, the place where our line of sight can reach is nothing to the curvature of the earth, and the earth as seen from that point is flat.

It was only when the footsteps of modern humans could spare the earth that they discovered that the earth was round. For example, if you are sailing in the sea, you will notice that the ship on the opposite side is showing the pole instead of the bow, which indicates that there is a certain curvature of the earth. It is a fact that the earth is round, and what we see is indeed flat, which also proves from the side that what we see with our eyes is not necessarily true, many things we need to find through seeing, verified through practice, and prove through science, the road of science is destined to be lonely!

A tribute to the scientific researchers who have fought for the truth all their lives.

The Earth is a super-large sphere, its surface area is about 510067866 square kilometers, and in extreme cases, excluding the effects of air quality, ground occlusion, etc., it is very limited to the human eye, and it can even be compared to the size of the Earth's 510067866 square kilometers. According to the formula of solid angle, it can be calculated that the curvature of the area seen by human beings on the surface of the earth with the naked eye is very small, and human beings cannot perceive it, so they will have the illusion that the ground is flat.

Because human beings are too small, compared to human beings, the earth is a super huge sphere, with a surface area of 100 million square kilometers, and the range of human vision is very limited under the premise of no obstruction. In terms of volume, human beings are even more insignificant, the volume of the earth is about: one trillion cubic kilometers, the volume of human beings is about cubic meters, if the earth is compared to the Pacific Ocean, then an adult is just a drop of water in the Pacific Ocean, in the case of such a disparity in volume, a small part of the earth is already very large for human beings, so in the limited field of vision of human beings, the ground seen is flat.

In fact, the earth is an ellipsoidal sphere, and for human beings, the ground is indeed flat, why? In fact, there is a simple example, a small thing is based on a very large ellipsoid, and what he sees must be flat. It's like an ant on top of a big balloon, and if you look at the ellipse from the ant's point of view, then it must be flat first, and then you will see that it's a sphere or an ellipsoid at an angle.

We can't feel the ellipse of the earth on the earth, in fact, we can't feel many things on the earth, for example, although you are sitting here now, but in fact you are "moving" rapidly, including the ground under your feet, the earth's plate is also moving at any time, etc., in fact, the example of the earth's rotation is to tell everyone that the earth is too big for us humans, and you must observe from an angle to see the essence of the earth.

Because the ancients did not have space telescopes, rockets, and so on, they thought that the sky was round, and the stars, sun, and moon were revolving around us, and the earth was flat, with a dome on it. But modern science has been advancing since the first Soviet satellite, and we can now not only see the Earth from space, but the Earth satellites of various countries can monitor any situation on the Earth anytime and anywhere, not to mention problems on the Earth's ground.

As soon as you reach a certain height, you will see that the ground is not actually flat, it has a certain curvature, and this curvature is also known as the curvature of the earth. The data of scientists shows us the curvature of the earth intuitively, and the rock and land means that a person standing on an endless flat land, its farthest viewing angle is about a kilometer, that is, the curvature of a meter or a kilometer, which we cannot observe.

The endless horizon we saw was a great view.

You can see the footage taken at an altitude of 10,000 meters.

A few days ago, the note7 mobile phone photographed the earth at 33,000 meters,It seems to have a little meaning.,But it's still flat.,Next,It's directly photographed by the astronauts of the International Space Station.,Not to mention near the Kármán line:

The last photo** is of the Apollo 16 astronauts on their way to the moon with a Hasselblad cam of the Earth.

If we live in the center of the earth, not on the surface of the coarse core, it is estimated that we don't even know what shape the earth is, it is a covered cauldron, haha, if you are a Saturnian, the earth you see is a pixel ......It is not clear whether it is round or square, and it is very important to observe with the help of astronomical instruments, after all, the human eye can see things for a limited time.

The ground is curved, not completely flat, just because people and animals are too small to feel that the earth is round on the ground.

The ground we see is only a tiny fraction of the earth, and because it's so small, it's flat.

The ground is actually round, but we humans are so small that we think the ground is flat in comparison.