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Time Dilation Formula / Calculator

timedilationformula.com

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Re: Time Dilation Formula / Calculator

#21

Post by Rhapso »

ANewFormation wrote: post #14
alhadrad wrote: post #6

Earlier quoted context omitted.

I was wondering about this too—it's super interesting! Did you create this? Could you add graphs showing acceleration and deceleration? Also, this might be a dumb question, but how does mass factor into the energy calculations? I would love to see graphs that include the multiple stages of travel (acceleration and deceleration) as well as the mass of various kinds of fuel required for different propulsion systems suc…

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"

Re: Time Dilation Formula / Calculator

#22

Post by tomtom1337 »

ben_w wrote: post #20
Workaccount2 wrote: post #18

Fascinating that if you could accelerate at 1.5g, it would only take you 18 years to reach the edge of the visible universe

And with that kind of gamma factor, the CMB will start evaporating you via positron-electron pair production.

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

Re: Time Dilation Formula / Calculator

#23

Post by floxy »

tomtom1337 wrote: post #22
ben_w wrote: post #20

Earlier quoted context omitted.

And with that kind of gamma factor, the CMB will start evaporating you via positron-electron pair production.

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 for others, they could be high enough in energy to produce electron-positron pairs. Seems like another one of those relativity related paradoxes. Only fast-moving observers (relative to the CMB) are seeing constant pair production from the CMB photons?

Re: Time Dilation Formula / Calculator

#25

Post by monster_group »

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 down to zero and reverse direction. At that moment the frame is no longer inertial. While turning around, the traveling twin will see the stationary twin age very quickly (enough to catch up with their earth age), so when they meet there's no paradox. For each of them the other has aged as per their observations.

Re: Time Dilation Formula / Calculator

#26

Post by ANewFormation »

tmountain wrote: post #17
ANewFormation wrote: post #13

Earlier quoted context omitted.

I'm not one to nitpick tools to grok things but I think this could confuse more than help! Because everything is relative to something else - and your example of the pendulum on a ship is suggestive of a "real" velocity, which does not exist. I think a far easier scario to imagine is some ship flying away from Earth, and this ship has a magic button to release an impulse enough to give it a 10% of the speed of light…

"If our ship travels 20,000 light years in 40 years (from the perspective of those on the ship) then that would take a "real" 20,000 years from the perspective of those on Earth" This part just breaks my brain. I've been reading about this stuff for decades, and it just does not compute. It's also a little funny because there's basically zero incentive for the folks on earth to send astronauts away at near-light spee…

Yip the reality that the speed of light is fixed, but the 'speed' of time is variable is just so intuitively absurd.

This is the reason that I find things like the Fermi Paradox no more than mildly interesting.

It implicitly assumes we have a sound understanding of the fundamentals of the universe yet each revolutionary discovery we make soundly refutes that assumption.

And with the vast number of 'known unknowns' and an unknowable number of unknown unknowns, it seems ridiculous to imagine we're anywhere near the end of revolutionary discoveries.

Re: Time Dilation Formula / Calculator

#27

Post by sigmoid10 »

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 whole site seems very much like it is AI generated. In particular the css is very close to what I've seen ChatGPT generate when I used it to create similar things.

Re: Time Dilation Formula / Calculator

#28

Post by ben_w »

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…

Correct.

> Seems like another one of those relativity related paradoxes. Only fast-moving observers (relative to the CMB) are seeing constant pair production from the CMB photons?

Both observers agree about pair production.

Pair production obeys conservation of momentum and energy — although the equations allow both to be conserved with two photons interacting, the practical effect here is CMB photons interacting with the spaceship hull: the observer in the CMB-rest-frame will see very low energy photons doing this with a high-velocity hull, and the spaceship frame will see very high energy photons doing this with a stationary (to them) hull.

That said, I'm told that accelerating observers can, during the acceleration, disagree about what particles exist around them: https://en.wikipedia.org/wiki/Unruh_effect

(Hmm, and now I'm wondering if the Unruh effect is really as described — if different quantum fields contribute at different rates, or have cut-offs at different scales, that would automatically also create something that, if you squint, will look a bit like an approximation of MOND… sadly, this is beyond my competence at this time).

Re: Time Dilation Formula / Calculator

#29

Post by WhitneyLand »

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.

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