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Time Dilation Formula / Calculator

timedilationformula.com

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Re: Time Dilation Formula / Calculator

#31

Post by nyrikki »

monster_group wrote: post #25

Author's description of twin paradox is incorrect. In fact, the paradox is not described at all. The paradox is that since motion is relative then from both twin's perspective the other twin goes on a journey and ages slowly. So why it is that on returning, only the traveling twin has aged slowly? The answer is that both twins indeed see each other age slowly but for the traveling twin to come back they have to slow…

The twin paradox holds in a Pacman universe where there is no change in direction.

The main issue with the twin paradox is that it demonstrates where our euclidian intuition fails us.

There are several interpretations on how to resolve it, but they are all just flawed lenses, intended to help you along a curriculum until you understand the math, and also understand the limitations of intuition.

The 'turn around' explanation is part of that and unfortunately often sold as the ultimate resolution.

Re: Time Dilation Formula / Calculator

#32

Post by jdawg777 »

dandanua wrote: post #4
roter wrote: post #3

How do you stop so you don't go whizzing past Alpha Centauri at near light speed? :)

An intelligent alien race, living there, will be able to catch you, don't you watch sci-fi movies? The real question is from what you can get 4.13e+19 Jouls, required to reach Alpha Centauri in about 9 years of traveler's time.

If you use fission, Uranium 235 has 83.14 TJ/kg. So you would need about 500 metric tons of it.

Re: Time Dilation Formula / Calculator

#33

Post by whatshisface »

Rhapso wrote: post #21
ANewFormation wrote: post #14

Earlier quoted context omitted.

Relativistic mass increases are an observed effect. So if you're on the relativistic starship (as these are usually called) your mass does not change as your relative velocity does. But for an at rest observer, your ship's mass would approach infinity as its speed approaches the speed of light. This is the reason the ship would never be observed as hitting the speed of light. In practical terms this is also why parti…

I really really wish they would call it "apparent mass". It is entirely an observer effect. Its entirely "that ship throws propellant out the back but they don't end up going as fast as Newton thinks it should, so it must have more mass than we think"

If there are many objects moving in many directions, you won't be able to find a reference frame in which the mass of the system is equal to the sum of the rest masses of the objects.

Re: Time Dilation Formula / Calculator

#34

Post by whatshisface »

floxy wrote: post #23
tomtom1337 wrote: post #22

Earlier quoted context omitted.

I didn’t understand this. What is it about the gamma factor that will cause the cosmic microwave background to evaporate you?

I'm assuming that ben_w is referring to the blue shift in the CMB that you will see in front of you. And pair production is the process of turning sufficiently high energy light into matter. https://en.wikipedia.org/wiki/Pair_production https://www.imperial.ac.uk/news/149087/scientists-discover-t... But I've never given thought to the fact that for some observers the microwave background are low energy photons, and f…

In the reference frame of the Earth a starship would be seen ramming in to stationary dust and long wavelength light.

Re: Time Dilation Formula / Calculator

#35

Post by SirMaster »

jvanderbot wrote: post #7

Tangential, but I want to share the thought experiment that made time dilation click for me. We know everything (every effect, etc) has a speed-of-light limit. Imagine a metronome ticking out time. It ticks back and forth. Put the metronome on a space ship. Now slowly increase the velocity of the space ship. As the space ship speed increases, the "pendulum" weight now has more and more velocity (the space ships veloc…

Maybe it's completely wrong, but I always thought about it as a dimension, and if you view time as the 4th dimension.

For example imagine just 2 dimensions. If you can only travel at the speed of light you could go at the speed of light in the x-axis, or at the speed of light in the y-axis. But if you want to go diagonally in both dimensions, you have to split your travel speed up between both such that when added together they don't exceed light speed.

If we view time as a dimension, then either you can stay at rest and travel through time at "full speed", or you can travel in the x, y, or z, axis at up to light speed, but in order to do so, you need to "give up" some of your traveling through time dimension. Such that your x+y+z+time "speed" do not exceed the speed of light.

Re: Time Dilation Formula / Calculator

#36

Post by nayuki »

monster_group wrote: post #25

Author's description of twin paradox is incorrect. In fact, the paradox is not described at all. The paradox is that since motion is relative then from both twin's perspective the other twin goes on a journey and ages slowly. So why it is that on returning, only the traveling twin has aged slowly? The answer is that both twins indeed see each other age slowly but for the traveling twin to come back they have to slow…

This is an extremely detailed explanation of the twin paradox that covers things from multiple angles, even situations that involve no acceleration: https://www.youtube.com/watch?v=vv5d5KHKDVE

Re: Time Dilation Formula / Calculator

#37

Post by timewizard »

WhitneyLand wrote: post #29

The wording is misleading: [When you move through space quickly, you move through time slowly] Why all the “you”? This makes it sound like you would personally experience slowness. Could be clarified to say it’s only according to the perception of others.

What you will experience is the apparent size of the Universe itself changing in proportion to the time dilation along your direction of acceleration. It is necessarily an observable phenomenon due to the constancy of the speed of light.

Re: Time Dilation Formula / Calculator

#38

Post by euroderf »

monster_group wrote: post #25

Author's description of twin paradox is incorrect. In fact, the paradox is not described at all. The paradox is that since motion is relative then from both twin's perspective the other twin goes on a journey and ages slowly. So why it is that on returning, only the traveling twin has aged slowly? The answer is that both twins indeed see each other age slowly but for the traveling twin to come back they have to slow…

Thank you for this explanation. So it is time spent in a non-inertial frame - decelerating and reversing direction.

Re: Time Dilation Formula / Calculator

#39

Post by Rhapso »

whatshisface wrote: post #33
Rhapso wrote: post #21

Earlier quoted context omitted.

I really really wish they would call it "apparent mass". It is entirely an observer effect. Its entirely "that ship throws propellant out the back but they don't end up going as fast as Newton thinks it should, so it must have more mass than we think"

If there are many objects moving in many directions, you won't be able to find a reference frame in which the mass of the system is equal to the sum of the rest masses of the objects.

correct. This is not a contradiction.

A reference frame is definitionally a point from which you would measure an "apartment mass". The rest mass isn't relevant to a reference frame where that mass isn't at rest. This is true at all scales.

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