Einstein Pedometer App Measures Relative Time Gain

cylonlover writes "Among other things, Einstein's theory of special relativity says that as an object's velocity increases, time as experienced by the object will slow down when compared to another object traveling at a lower velocity. This means that a 'relatively' short round trip on a space ship traveling at close to the speed of light would see you arrive home having aged less than those back on Earth. While the greater the velocities involved, the greater the effect, the theory applies to all relative movement. Now there's an iPhone app that will let you know just how many extra nanoseconds you've gained by getting moving as opposed to sitting on your rear end."

Comments

I used the extra 300 femtoseconds

[Anonymous Coward]

To beat you guys to first post. Bah!

Re:I used the extra 300 femtoseconds

[a_nonamiss]

Wow a witty and topical first post. My hat goes off to you good sir.

You gained none...

[sznupi]

It doesn't matter much how the time in your frame of reference relates to times of "stationary" observers; it's still the same amount of time for you.

Of course, the gain (and much larger than nanoseconds) might be there vs. just sitting on your rear end. But it depends greatly on the type of movement, for example whether it involves regular exercise.

Re:You gained none...

[Chris Burke]

It doesn't matter much how the time in your frame of reference relates to times of "stationary" observers; it's still the same amount of time for you.

True! But it does bring the future to you that much quicker. And let me tell you, from my perspective of a person from a few nanoseconds ago, the present-ne-future is an amazing place!

Re:You gained none...

[stealth_finger]

Lateral thinking; what if I would sit on the read end of someone else?

You get AIDS

relative to what?

[ron_ivi]

Wouldn't this "gain" depend on which direction you're walking - along with the rotation of the earth, or against it?

Or if you're comparing to non-earthly reference points - along with the revolution around the sun & galaxy or against them?

Re:relative to what?

[Cytotoxic]

It isn't just about math. These effects have been proven experimentally - just not by sending a human off to Alpha Centauri. Follow the references for more relativity fun. I personally find length dilation to be the most interesting and difficult to get my head wrapped around.

Fun thought experiment:

A 100m rocket speeds toward a 90m hangar building at .99C. As the rocket passes through the open doors of the hangar the operators of the building close both sets of doors while the rocket is entirely inside the building. This is possible because of the length dilation happening at the high relativistic speeds (the rocket is compressed to less than 90m from the view of the hangar).

But from the point of view of the ship, it is the hangar that is approaching at .99c. Therefore the hangar is foreshortened - even shorter than 90m - leaving more than 10m too much rocket hanging out. What do each of the door operators and the pilot of the rocket see happening?

This is a fun use for all that math you learned to figure out relativity. Even though both frames of reference see things in entirely incompatible ways, both versions of the truth are entirely consistent via relativity.. Fun!

Re:relative to what?

[Lanczos]

The problem is that the article is a little bit wrong. In special relativity lets say I'm sitting next to someone and then I go for a walk and come back. When we compare clocks they will be the same since otherwise there would be symmetry breaking and we could establish a preferred inertial frame. Now in general relativity the symmetry is broken by the bending of time caused by my acceleration and when I return to my desk I will be younger than my stationary friend. i.e. this is all a consequence of general relativity not special.

Re:relative to what?

[magarity]

You should rest easy! It's been confirmed directly using planes and atomic clocks:

I'm glad those experiments were conducted back in the 70's. If someone thought that up now, well, just imagine what the TSA goons would do if you said the mysterious electronic device in your carry on was an atomic clock.

Badly named

[Anonymous Coward]

It's actually a pedantometer.

You LOSE time not gain it.

[digiplant]

Think of it this way: Two guys have a deadline in an hour. Guy #1 sits at his desk and does nothing. Guy #2 zips around at a high velocity and returns to meet guy #1. Both guys check their watch, guy #1 notes an hour has past, while guy #2 notes that half an hour has past. Although guy #2 has aged less, he actually had less time to work to meet the deadline. In the spirit of the original post, guy #2 has lost time instead of gained it.

Philosophical Exercise

[hellfire]

The time one lives on this planet is relative to measurements made by other people and by other devices. Your watch on your own wrist is probably the most accurate personal time you can get, but you have to adjust it based on other clocks around you to remain in sync with the rest of the world. Even more so, computers and phones now regularly ping a clock server to get an updated time automatically, and that server is somewhere else, being stationary. Time on the Earth is measured in terms of the velocity of the planet's orbit and rotation, but not in terms of your personal velocity relative to the sun or earth itself. The earth rotates and orbits at a specific velocity. If you move, your velocity relative the sun is different than the planet itself.

However, by moving, based on the theory of relativity, you are gaining a fraction of a fraction of a second by moving faster than the world around you. The clock is a philosophical exercise exploring relativity, and it's not like you'll gain 200 relative years by constantly walking or running anywhere, but it's fun to observe relativity in action. The "gain vs loss" here is that 1 second for you is still 1 second, but if you were say running, 1 second for you is, for example, 1.000000000000000000000000000000000000000000000000000000000000001 seconds for everyone you pass that are standing still. So you gain that fraction of a second relative to the world around you, and thus travel into the future a little faster than others.

Re:Philosophical Exercise

[wood_dude]

No, I'm at rest. Everything else is revolving around me. It's a chaotic dance to be sure, but I'm at the center of it ! :)

Re:Philosophical Exercise

[lxs]

No the twin paradox is resolved by noticing that one twin has to accelerate at least twice on his round trip (and thus his frame of reference isn't in an inertial frame of reference and therefore not valid for calculations in special relativity) while the stationary twin doesn't accelerate at all.

Calculates, not measures.

[nedlohs]

Measuring would just a tad more difficult...

22 more nanoseconds

[mangu]

There is at least one hobbyist that has measured it by taking a surplus rubidium oscillator up mt. Rainier. "It was the best extra 22 nanoseconds I've ever spent with the kids,"

Re:You can STILL be lazy!!!

[benjamindees]

How many plane trips would I have to take to go backwards in time all the way to the 70's?