What is the synopsis of The Theory of Relativity and A Brief History of Time ? Thank you.

It's popular science, a brief history of time can still be understood, and it is recommended to buy it and take a look.

The theory of relativity mainly expounds the laws of motion of matter.

The principle of relativity is a basic theory about space-time and gravity, mainly founded by Albert Einstein, and is divided into special relativity (special relativity) and general relativity (general relativity). The basic assumptions of the theory of relativity are the principle of invariance of the speed of light, the principle of relativity, and the principle of equivalence. The theory of relativity and quantum mechanics are the two fundamental pillars of modern physics.

Classical mechanics, which laid the foundation of classical physics, is not suitable for objects moving at high speed and objects under microscopic conditions. The theory of relativity solves the problem of high-speed motion; Quantum mechanics solves problems under microscopic subatomic conditions. The theory of relativity has greatly changed mankind's "common sense" concept of the universe and nature, and has put forward new concepts such as "simultaneous relativity", "four-dimensional space-time" and "curved space".

Professor Hawking is a modern science popularizer: his masterpiece is "A Brief History of Time" written in 1988, which is an excellent astronomical science popularization**. The author's imagination is rich, the ideas are wonderful, the language is beautiful, the words are exquisite, and it is even more astonishing, outside the world, the changes in the future are so magical and wonderful.

The book has been sold in 25 million copies and translated into nearly 40 languages. In 1992, the £3.5 million film of the same name came out. Stephen Hawking firmly believed that the basic ideas about the origin of the universe and life could be expressed without mathematics, and that the world should be able to understand his esoteric theories through the audiovisual medium of film.

This book is a popular book about exploring the nature of time and the forefront of the universe, and it is one of the most important contemporary classics on the scientific thought of the universe, which has changed the concept of the universe of mankind. As the undisputed authority on cosmology, Hawking's research achievements and life have always attracted a wide range of readers, and "A Brief History of Time Continuation" is for readers who want to know more about Professor Hawking's life and his teachings. The book recounts Professor Hawking's life and research work in the form of frank and honest private interviews, showing the real "people" behind a huge theoretical framework.

The book is not an ordinary oral history, but a deeply moving and fascinating portrait and description of one of the greatest minds of mankind of the twentieth century. For lay readers, this book is undoubtedly an opportunity to enjoy the fruits of human civilization and a source of valuable inspiration. The Stephen Hawking Lectures: Black Holes, the Infant Universe and Beyond is a collection of 13 articles and speeches written by Stephen Hawking between 1976 and 1992.

Imaginary time, the birth of a baby universe with black holes, and scientists' quest for a completely unified theory are discussed, with unique insights into free will, the value of life, and death.

What determines the existence of time? How is it stated in the theory of relativity?

I think the concept of time is determined by space and human beings, there is space and time or space does not define the concept of time at all, it is just the birth, old age, sickness and death that human beings themselves come up with and people want to define the non-spatial coordinates given by the relative movement of objects, have you ever felt this way, which is longer between you going to happy for 10 minutes and you standing on the coals for 10 minutes? It's a way for the human mind to define time, and it might be a little ridiculous. When you ask about time lapse and relativity, I think the formula of special relativity seems to be open-rooted, maybe there is a symbol?

A Brief History of Time", I bought it and read it, but it was empty and weak. Not qualified for the theory of relativity, although Hawking is also a theoretical physicist, but I think it is still a cut short of Einstein.

Stephen Hawking's A Brief History of Time is not comparable to Einstein's theory of relativity, which has had a much greater impact on the development of science than the book A Brief History of Time. To put it bluntly, "A Brief History of Time" is just a popular science work, and the theory of relativity is the theory that supports modern logistics. When I was in middle school, I came into contact with Stephen Hawking's "The Universe in the Shell" and "A Brief History of Time", which are much easier to understand than boring popular science books.

Stephen Hawking's story is very friendly and inspirational, however, his status in the physics community is not prominent.

The theory of relativity is a theory proposed by Albert Einstein to study space-time and gravity, which, together with quantum mechanics, laid the foundation of modern physics. The theory of relativity is broad and narrow, and the difference is mainly whether or not gravity (bending space-time) is involved in the study of the problem. Special relativity is used to study problems where gravity is not involved or can be ignored, while general relativity is used to discuss problems when gravity is not negligible.

The theory of relativity is mainly applied in Tianhao wheel physics and Huaidou quantum physics. For example, the mass-energy equation proposed in the special theory of relativity, mass and energy have a definite equivalent relationship, and the mass of an object is m, then the corresponding energy is: e=mc, which played a key role in the development of atomic bombs and hydrogen bombs.

A Brief History of Time》 In 1988, the British physicist Stephen Hawking published the popular science book "A Brief History of Time". The book consists of 12 chapters, covering the most cutting-edge knowledge of physics, such as the image of the universe, space and time, the expanding universe, the uncertainty principle, black holes, and the origin of the universe.

A Brief History of Time, the main chapters are: Chapter 1 Our Images of the Universe; Chapter 2 Space and Time; Chapter 3: The Expanding Universe; Chapter 4 The Principle of Uncertainty; Chapter 5 Elementary Particles and the Forces of Nature; Chapter 6: Black Holes; Chapter 7 Black Holes Are Not So Black; Chapter 8: The Origin and Destiny of the Universe; Chapter 9: The Arrow of Time; Chapter 10: Wormholes and Time Travel; Chapter 11 The Unification of Physics; Chapter 12 Conclusion.

To sum up, the book "A Brief History of Time" and the theory of relativity are not on the same level.

Parity. One is the cornerstone and the other is the yard brick, which is not comparable.

You don't need to know the answer to a question.

Einstein.

Albert Einstein once proposed the theory of special and general relativity:

1. The two basic assumptions of the special theory of relativity: the ridge.

Some physical quantities may vary depending on the choice of reference frame, but the mathematical form of the physical laws is exactly the same in all inertial frame of reference (i.e., the physical laws to be followed are the same).

2. Two basic assumptions of general relativity:

1) The principle of general relativity: In any frame of reference, the physical laws are the same (unlike the special theory of relativity, the general theory of relativity proposes that all physical laws are the same in both inertial and non-inertial frames).

2) Equivalence principle: A uniform gravitational field is equivalent to a reference frame that accelerates uniformly. This means that a non-inertial frame can be seen as an inertial frame, except that there is a uniform gravitational field behind it, because inertial force and gravity are indistinguishable in non-inertial frames.

A Brief History of Time:

1. Our image of the universe: what kind of image (state) of the universe we live in

3. The Expanding Universe: The Universe is constantly expanding, and some views about it.

4. Uncertainty Principle: Emphasis on the uncertainty principle and its effects.

5. Elementary particles and the forces of nature.

6. Black holes. 7. Black holes are not so dark.

8. The origin and destiny of the universe.

9. Time arrow.

10. Wormholes and Time Travel: Very interesting, introducing the content of time travel and the contradictions caused by time travel.

11. The Unification of Physics: Introducing the "Great Unification Theory".

12. Conclusion.

For 4-dimensional straight space-time (Minkowski space-time), we can distinguish between temporal and spatial coordinates, because the spatio-temporal metric (4-dimensional matrix) is a diagonal matrix, and the number difference is positive, and 3 positive numbers in the 4 diagonal elements describe 3 spatial coordinates, and the other negative number describes the temporal coordinates.

However, for non-straight space-time, the degree matrix may be very complex, and it may no longer be a diagonal matrix, so the time coordinates and space coordinates will be coupled together, such as the energy layer region in the Kerr-Newman black hole, the space-time coordinates are not distinguished, there is no clear concept of time and space, only the overall concept of "space-time". Another example is the simplest black hole, the Schwarzschild black hole, in the event horizon, although the degree matrix is still diagonal, but the time coordinates become positive and the space coordinates become negative, resulting in the phenomenon of interchange of time coordinates and space coordinates.

Because time and space can be distorted. Imagine what time and space would be like under the extreme conditions of a black hole.

This is called the Getwin Fallacy.

The Gewinon Paradox or Getwin Fallacy is a thought experiment on the special theory of relativity. Here's how it goes: There are twin brothers, one aboard a spaceship for a long-distance space trip, while the other stays on Earth.

As a result, when the traveler returns to Earth, we find that he is younger than his brother who stayed on Earth.

This result is inferred by the special theory of relativity (the phenomenon of time dilation of a moving clock) and can be verified experimentally: we can detect mesons produced in the upper layers of the atmosphere. Without time dilation, those mesons would have decayed before they reach the ground.

But if we think about this from the point of view of the brother in the spaceship, we seem to come to a contradictory result: the traveler in the spaceship will see the Earth leave him at high speed and then return at high speed. He can assume that his brother on Earth is the moving clock, so it is his brother who is affected by time dilation, not himself.

Special relativity states that all observers are equally meaningful, and that no frame of reference is preferential. So the traveler would expect to see a younger twin when he returns to Earth, but that's the opposite of what his brother thinks - so who is right?

The result is that the traveler's expectation is wrong: special relativity does not say that all observers have equal significance, but only observers in the inertial frame (i.e., observers who do not perform accelerated motion) have equal significance. But the spaceship undoubtedly accelerates at least once during its journey, so the Voyager is not an inertial frame.

On the other hand, the brother who remained on Earth was in an inertial frame for the entire voyage (if we ignore the relatively small acceleration caused by the mass and movement of the Earth), so he was able to distinguish him from his brother.

Some people who solve this paradox will think that special relativity cannot be applied to accelerating objects, but only general relativity, which is incorrect. For example, the age of the twin brothers can be accurately calculated by finding the integral of the spacetime interval in the space-time path traveled in any of their inertial frames (these paths are called worldlines). The approximation method can be used to calculate the relativity behavior of an accelerating spacecraft (see Relativity Rocket).

The only case where special relativity doesn't apply is when the effects of gravity can't be ignored, and that's when we really need to use general relativity.

To put it simply, you grasp the principle that two objects in relative motion see who is in the inertial frame and who is not, and that time passes normally in the inertial frame and slows down in the variable speed frame.

And if you want to know how fast both sides see each other passing, add some points.

Hello, this kind of problem is not enough to explain it with the special theory of relativity alone. Because whether it is a person on the ground or a person on a train, the frame of reference used when observing each other is not an inertial frame. As you can imagine, since you end up standing together to compare your age, it is impossible for you for the train to move in a straight line at a uniform speed.

Let's simplify the problem and assume that a train is traveling in a straight line in one direction at a constant speed near the speed of light. At this point, both you and the people on the train will think that you are stationary, so you will both think that the other person is younger than you. Similarly, when the train comes back in the same way, you will also consider yourself older than each other.

Since the result of these two processes is that you think you are old and he thinks he is old, is this a fallacy? The key is the process of the train turning around!! (Let's assume that this U-turn process is instantaneous).

From the perspective of the people on the ground, that is, to you, you are stationary, and the train itself changes speed, and this process has nothing to do with you. But the person on the train is different, he also thinks he is stationary, but he feels a force that "pulls" you towards the train. This means that the train is in a gravitational field.

In this case, you need to change the frame of reference. According to the Lorentz conversion, your age is increased by a large chunk "for no reason" in the process.

So in general, when you stand up again, he's going to be younger than you.