Time dilation is a very simple consequence of the fact that the speed of light is the same in all inertial frames of reference. It is something that you observe in objects moving relative to you, never something that you "feel" yourself or that happens to you directly.DavidMCR said:I'll confess, I joined this forum solely to understand the reasoning behind the concept of time dilation, and to see if it is correct or not. If anyone could help me understand it better, and converse with me, I'd greatly appreciate it.
phinds said:Time dilation is a very simple consequence of the fact that the speed of light is the same in all inertial frames of reference. It is something that you observe in objects moving relative to you, never something that you "feel" yourself or that happens to you directly.
What readying have you done and what is it that you don't understand?
Nugatory said:There are three related phenomena here: time dilation, length contraction, and relativity of simultaneity. All three are involved any time that two observers are moving relative to one another (for example, a spaceship flying away from earth) - it's a package deal.
My preference is to start with relativity of simultaneity; it's easier to explain time dilation and length contraction after you understand RoS than the other way around.
Do not confuse yourself by taking on the twin paradox (leave Earth on a fast-moving spaceship; turn around and come back; on return you are younger than the twin you left behind) or time dilation caused by gravity. Those are different phenomena than basic time dilation and you don't want to take them on yet.
Cheerslomidrevo said:I agree with the above replies. My suggestion would be, to read this Feynman lecture first. Whatever questions you might have after, I am sure people here would be happy to help you.
You certainly need to stop thinking like this. It is blocking your progress in understanding how the Universe actually works. The bottom line is that the Universe does not care how you look at things or what you find intuitive, in particular when what you find intuitive is not how the Universe works.DavidMCR said:The way I look at it (and admittedly from a non-physicist pov) is everything happens concurrently; therefore the only way someone becomes "younger" is if they were to be "removed" from this physical universe, temporarily.
That would be because you do not have an understanding of what time is and how it relates to the relativistic spacetime. The view that "everything happens concurrently" is obsolete and will unfortunately not get you anywhere. In relativity, as has already been stated here, you have to get rid of "simultaneous" or "concurrently" as a physically meaningful concept.DavidMCR said:See, when I hear the idea that someone ends up younger upon returning from their spaceship journey compared to those on earth, I can't but help think it's lies.
For this, the place that you should start is the experiments that demonstrate time dilation. See section 4 here:DavidMCR said:to see if it is correct or not
Orodruin said:You certainly need to stop thinking like this. It is blocking your progress in understanding how the Universe actually works. The bottom line is that the Universe does not care how you look at things or what you find intuitive, in particular when what you find intuitive is not how the Universe works.That would be because you do not have an understanding of what time is and how it relates to the relativistic spacetime. The view that "everything happens concurrently" is obsolete and will unfortunately not get you anywhere. In relativity, as has already been stated here, you have to get rid of "simultaneous" or "concurrently" as a physically meaningful concept.
Which part? It is difficult to tell exactly what you are asking about when you quote the entire post.DavidMCR said:Why is that?
Fair pointOrodruin said:Which part? It is difficult to tell exactly what you are asking about when you quote the entire post.
Dale said:For this, the place that you should start is the experiments that demonstrate time dilation. See section 4 here:
http://www.edu-observatory.org/physics-faq/Relativity/SR/experiments.html
Time dilation is an experimentally validated fact of nature. It is best to start your studies with that understanding. That way you are more willing to confront your own misconceptions rather than assume deception.
Essentially because the concept of simultaneity is observer (or, more accurately, convention) dependent. What is simultaneous for one observer is not necessarily the same as for another observer. Einstein's classic example with a train and some lightning rods gives you the first hints as to why this is so. It is a direct consequence of the experimental fact that the speed of light is invariant. No, it is typically not intuitive for most people, but most people's intuition is based on everyday situations where speeds are much smaller than the speed of light.DavidMCR said:Fair point
"In relativity, as has already been stated here, you have to get rid of "simultaneous" or "concurrently" as a physically meaningful concept."
You are mistaken - it is true. The experiment has been done (with airplanes instead of spaceships) and the effect is very small but measurable. The principle is further tested with the clocks on the GPS satellites every day - if we did not allow for time dilation effects the GPS system would not work.DavidMCR said:See, when I hear the idea that someone ends up younger upon returning from their spaceship journey compared to those on earth, I can't but help think it's lies.
And this is one of the reasons that I suggested you start with relativity of simultaneity. Google for "Einstein train simultaneity" and see what you find.The way I look at it (and admittedly from a non-physicist pov) is everything happens concurrently;
You cannot become younger than you were - that would be time going backwards and that's not possible. You can, however, age less quickly than someone else if less time passes on your path through spacetime than the other person's. But as I said, this is a different phenomenon than time dilation - you have to understand the basics first....therefore the only way someone becomes "younger" is if they were to be "removed" from this physical universe, temporarily.
Nugatory said:You are mistaken - it is true. The experiment has been done (with airplanes instead of spaceships) and the effect is very small but measurable. The principle is further tested with the clocks on the GPS satellites every day - if we did not allow for time dilation effects the GPS system would not work.
You might also want to take a look at the sticky thread at the top of this subforum: https://www.physicsforums.com/threads/faq-experimental-basis-of-special-relativity.22903
And this is one of the reasons that I suggested you start with relativity of simultaneity. Google for "Einstein train simultaneity" and see what you find.
You cannot become younger than you were - that would be time going backwards and that's not possible. You can, however, age less quickly than someone else if less time passes on your path through spacetime than the other person's. But as I said, this is a different phenomenon than time dilation - you have to understand the basics first.
The emphasis is mine.Our goal is to provide a community for people (whether students, professional scientists, or hobbyists) to learn and discuss science as it is currently generally understood and practiced by the professional scientific community.
Prior to civilizations' becoming seafaring, they lived on a flat Earth with a Sun of unknown nature traveling across the sky once a day (perhaps on a chariott?). They weren't altogether wrong about the Earth being flat on the scale they were viewing it.DavidMCR said:See, when I hear the idea that someone ends up younger upon returning from their spaceship journey compared to those on earth, I can't but help think it's lies.
The way I look at it (and admittedly from a non-physicist pov) is everything happens concurrently...
Time dilation is a concept in physics that states time passes differently for objects in motion compared to those at rest. This phenomenon occurs due to the theory of relativity, which suggests that time and space are relative to the observer's frame of reference.
Time dilation occurs when an object moves at high speeds or experiences strong gravitational forces. This causes a difference in the passage of time between the moving object and a stationary observer. The faster an object moves, the slower time passes for it.
The formula for calculating time dilation is t = t0/√(1-v2/c2), where t is the time measured by the moving object, t0 is the time measured by the stationary observer, v is the velocity of the moving object, and c is the speed of light.
Time dilation plays a crucial role in space travel as it affects the perception of time for astronauts. As they travel at high speeds, time passes slower for them, which means they age slower compared to people on Earth. This phenomenon must be taken into account when planning long-distance space missions.
Yes, time dilation has been proven through various experiments and observations, including the famous Hafele-Keating experiment and the use of atomic clocks on GPS satellites. It is an essential concept in modern physics and has been confirmed by numerous experiments and observations.