Proofing a few paragraphs on relativity

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In summary, Einstein's theory of relativity states that the speed of light is constant for all observers, regardless of their velocities. This leads to concepts such as time dilation, where an observer's sense of time slows down as their velocity approaches that of light. This also means that space and time are not absolute and independent, but are part of a four-dimensional space-time continuum relative to the observer. Additionally, Einstein's General Theory of Relativity views gravity not as a force, but as a curvature of space-time itself. This explains why time and space flow differently in different parts of the universe, depending on the distribution of mass. Overall, Einstein's theories revolutionized our understanding of space and time, and continue to be a fundamental aspect of
  • #1
jason_one
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I have to write a brief history of physics for this english paper I'm doing. The only part I don't have a strong knowledge of is relativity, so if anyone would like to check the following three paragraphs for me and tell me if I summed it up accurately, I would be very grateful.

"Einstein stated that the speed of light will remain constant for all observers no matter what their velocities are. This means that if I, at rest, observe a beam of light, I will see it traveling at 186,000 miles per second. Now, say I witness a man flying past me at a constant rate close to that of the speed of light. This does not mean that he will observe light traveling very slowly, but rather his sense of time has slowed down so that, to him, light still appears to travel at 186,000 miles per second. In fact if he had a watch on, I would see his watch as moving more slowly than mine. But, because in his frame of reference he is the one at rest and I am the one moving at close to light speed, he will observe that my watch is moving more slowly compared to his. This is called 'time dilation'. And not only will his clock appear to be slowed down to me, but he will also appear smaller to me and vice versa. If the two of us held out meter sticks, his would appear smaller than mine to me, and mine would appear smaller than his to him.

It is because of this nature of spatial and temporal relativity, Einstein concluded that the three dimensions of space and the single dimension of time are not absolute and independent of each other, but they make up a four-dimensional space-time continuum which is relative to the observer.

Einstein stated, in his General Theory of Relativity, that gravity is not a force that exists in space, as Newton had thought, but is actually a curvature of space-time itself. Einstein understood that being in a gravitational field was the equivalent to being in state of acceleration, which brought about a warp, or curve, in the fabric of space-time. This means, therefore, that time and space flow differently in different parts of the universe according to the distribution of mass."
 
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  • #2
but they make up a four-dimensional space-time continuum which is relative to the observer.

Might I suggest better wording for this sentance. Four-vectors are Lorentz invariant, someone might think otherwise after reading that.
 
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  • #3
jason_one said:
This does not mean that he will observe light traveling very slowly, but rather his sense of time has slowed down so that, to him, light still appears to travel at 186,000 miles per second.
Time dilation is part of the explanation for why he still sees the light travel at 186,000 miles per second, but it isn't the only part. If his rulers didn't contract relative to yours, or if his definition of simultaneity wasn't different than yours, then he wouldn't measure the same light beam to be moving at 186,000 miles per second even if his clocks did slow down.
 
  • #4
Berislav said:
Might I suggest better wording for this sentance. Four-vectors are Lorentz invariant, someone might think otherwise after reading that.

The four-vectors are not themselves Lorentz invariant. Their magnitudes are lorentz invariant.
 
  • #5
The four-vectors are not themselves Lorentz invariant. Their magnitudes are lorentz invariant.
I didn't want to seem pedantic with my previous post but yes, you are right, the Minkowski norms of four-vectors are Lorentz invariant, not the vectors themselves.
 
  • #6
Thanks for the help guys!
 
  • #7
And not only will his clock appear to be slowed down to me, but he will also appear smaller to me and vice versa. If the two of us held out meter sticks, his would appear smaller than mine to me, and mine would appear smaller than his to him.
To you, he would appear compressed in the direction of his movement, to be precise (or picky, one might say). Similarly his meter would appear shorter to you assuming both you and he are holding the respective meters parallel to each other's vector (arrow) of motion. If the meters are held vertically (perpendicular to motion's arrow), then they will appear only thinner relative to each other.
 
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1. What is the theory of relativity?

The theory of relativity is a scientific theory proposed by Albert Einstein in the early 20th century. It has two main components: the special theory of relativity and the general theory of relativity. The special theory of relativity deals with the relationship between space and time, while the general theory of relativity deals with the effects of gravity on the fabric of space and time.

2. What is the difference between special and general relativity?

The special theory of relativity deals with the relationship between space and time in the absence of gravity. It states that the laws of physics are the same for all observers in uniform motion. On the other hand, the general theory of relativity includes the effects of gravity and describes how massive objects, such as planets and stars, curve the fabric of space and time.

3. How does the theory of relativity impact our understanding of the universe?

The theory of relativity has revolutionized our understanding of the universe. It has provided a framework for understanding the behavior of objects moving at high speeds and in the presence of strong gravitational fields. It has also led to the development of technologies such as GPS, which rely on the principles of relativity to make accurate measurements.

4. Is the theory of relativity proven?

The theory of relativity has been extensively tested and has been proven to be accurate in explaining a wide range of phenomena. However, like all scientific theories, it is constantly being refined and updated as new evidence and discoveries are made. So while it is considered to be a well-established theory, it is always subject to further examination and refinement.

5. How can we observe the effects of relativity in our daily lives?

The effects of relativity may not be noticeable in our daily lives, as they are most pronounced at very high speeds or in the presence of extremely massive objects. However, some technological advancements, such as GPS and satellite communication, rely on the principles of relativity to function accurately. Additionally, some astronomical observations, such as the bending of light around massive objects, also provide evidence for the effects of relativity.

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