Question pertaining measurement and space

In summary, the concept of infinite distance between two points in space can be explained through measure theory, which states that even though there may be an infinite number of points between two finite points, the distance between them is still finite. Additionally, in calculus, an infinite series of numbers can have a finite sum, which can be applied to the paradox of Zeno's arrow, where a finite distance can be crossed in a finite amount of time, even if the time is broken up into an infinite number of intervals.
  • #1
BigM69
1
0
if there is an infinite amount of distance between two points in space because you can break that distance up into an infinite amount of different points then how can one move through space at all?
 
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  • #2
If we take two points a finite distance apart, there may be an infinite number of points between them, but the distance between them is still finite.

The detailed math on this gets into what's known as "measure theory". I'm not sure if you REALLY want a detailed mathematical answer, but if you do, you might try the math forums. About all I can remember about the topic is that if the measure of an infinite set of points such as the interval [0,1] is finite, the measure of ANY finite set of points turns out to be zero. I don't recall the axioms that were used to prove this offhand, though.
 
  • #3
Another way of addressing Zeno's paradox is to note the fact that in calculus, an infinite series of numbers can have a finite sum--for example, the sum of the infinite series 1 + 1/2 + 1/4 + 1/8 + 1/16 + ... is just 2. So if you want to travel one meter at a speed of half a meter per second, it'll take 1 second to cross the first half-meter, 1/2 a second to cross the next fourth of a meter, 1/4 a second to cross the next eight of a meter, and so on...so although you can break up the total time into an infinite number of time-intervals, the total time is still just 2 seconds.
 

1. How do you measure distance in space?

Distance in space is typically measured using light years, which is the distance that light travels in one year. It is also common to use astronomical units (AU) to measure distances within our solar system.

2. What is the difference between accuracy and precision in measurement?

Accuracy refers to how close a measurement is to the true or accepted value, while precision refers to how consistently the same measurement can be repeated. In other words, accuracy is about correctness and precision is about consistency.

3. How does the curvature of space affect measurements in astronomy?

The curvature of space, as described by Einstein's theory of general relativity, can affect the measurements of distances and angles in astronomy. This is because gravity can bend the paths of light and other objects, making them appear to be in different positions than they actually are.

4. Can we measure the size of the universe?

Currently, scientists estimate that the observable universe is about 93 billion light years in diameter. However, due to the expansion of the universe, we are unable to measure the entire universe beyond the observable limit.

5. How do scientists measure the mass of objects in space?

The mass of objects in space is often measured using their gravitational interactions with other objects. For example, the mass of a planet can be determined by observing the orbit of its moons or other nearby objects. Other methods, such as studying the effects of an object's gravity on light, can also be used to measure mass in space.

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