I don’t know how or why this question popped into my head (and I apologize, in advance, if I get the physics wrong) but…
Things age slower when traveling a substantial portion of the speed of light, right?
Britannica: “In accordance with the time-dilation effect, the elapsed time on the clock of the twin on the rocket ship will be smaller than that of the inertial observer twin—i.e., the non-inertial twin will have aged less than the inertial observer twin when they rejoin.”
So, hypothetically, I cut down a tree and saw the trunk into two 2’ sections. I keep one on earth and blast the other off into space at a substantial enough portion of light speed for the time dilation effect to occur. For, say, ten thousand years, at which point the rocket finds it’s way back to earth.
Then carbon date them both. The one that stayed behind dates to 10,000 years old. Would the rocket born section date to, maybe, only a few hundred years old? If so, is that because time dilation slows decay?
Time dilation slows everything including radioactive decay. Particle detectors on the Earth’s surface detect muons generated in the upper atmosphere, even though their decay time is so fast they should be gone by the time they get that low. Why? Time dilation.
Yes, radioactive decay (cf. half-life) is a function of time. You can see the same effect studying short-lived particles accelerated to high speeds in particle accelerators.
The decay of the carbon-14 being measured depends upon time, the same way that the age of anything else is effected by what is erroniously refered to as time dialation.
The time experienced by the object remaining at home is real for that object. The object travelling faster is also experiencing real time, not some dialation effect, that is the real time for that object.
Forget ‘time dialation’, that is just a tool to explain what is going on. The time for both objects is the real time for them. This is where relativity comes in. It is apparently part of the fabric of the universe or what we call space/time for lack of a better description.
The speed of an object is not really changing the time being experienced by that object. That is the real time for that object. There is no constant reference frame that can be refered to as ‘standard time’, it is all relative.
Yes! Not only is the increased decay time, in our frame of reference, of sub-atomic dilation traveling at near light speed velocities a consequence of time dilation, it’s the only way we can test the accuracy of the theory at such velocities. And it turns out they fit our theories to the t …
There are plenty of ways to test time dilation at slower speeds, but the results aren’t quite as obvious and spectacular.
Time is just plain different in reference frames that are moving with respect to one another. As are distances and simultaneity, which opens additional mind bending cans of worms if you tire of thinking of carbon dating traveling logs.
It’s weirder than that. The decay rate is the same, it’s time itself that changed. You’re focusing on radioactive decay, but the results of literally every other process you could mention - say, organic decay due to microorganisms - would also be measurably different.
Certainly no theory. There might be a model that describes such a thing, but I struggle to see how it could agree with experiments.
If you sent one piece of wood from here to alpha Cen, and then later sent the other piece of wood there with the same speed and acceleration portfolio, then they’d match when they met up again, because they’d both been through the same thing. But if you send one to alpha Cen, and then bring that same one back, it would be younger than the piece of wood that stayed on Earth. That’s because the situation is not symmetric: One piece changed reference frames, while the other stayed in a single reference frame.
On the other hand, if you sent one out on a constant-speed one-way trip to nowhere, then waited a while, and then sent the other one out even faster, so it eventually caught up, in that case, once they met up and you could compare the ships’ logs, the catch-up one would be younger.
The stay-at-home log experiences a peaceful existence. The traveling log experiences forces and accellerations. Those different experiences change its experience of time.
No, this is completely wrong. There is no time standard where the stay-at-home log is at rest in ‘normal’ time and the traveling log is somehow fighting against normal time and being stressed. Time is relative to each one’s speed, mass, location. Thats why it is refered to as relativity. Both are experiencing normal time, for them. There is no time standard. No normal time.
This is what is so hard for people to wrap their mind around. Time is related to gravity, and speed, and the mass of the object, the very fabric of the universe governs this. Space is not some empty thing, it is somewhat like moving an obejct throught water and then trying to ignore the effect that water is having on the object. There is a real substance we call space/time that prevents an object from moving faster than the speed of light.
Space/time is a real thing and movement within space/time is what causes these apparent differences of time. In which time may not even be a real thing at all, just an effect.
This is how time relativity was explained to me as a kid in school— We were shown a science cartoon with either Disney or Looney Tunes characters, I think. One character is in an open train car on a moving train dribbling a basketball. Another character is stationary, watching the train go by.
To the character dribbling the basketball on the train, the ball is going straight up and down. But to the stationary observer, the basketball is traveling not only up and down, but on a diagonal, due to the train’s movement. The basketball is taking a longer journey, and therefore is taking longer, to the stationary observer but not to the basketball dribbler on the train.
Of course the difference in that scenario is negligible, but imagine you are traveling near the speed of light. Everything, including every moving atom in your body and electron traveling through your brain is going on a much longer journey from the point of view of a stationary observer than to you.
I’ve always assumed that particle accelerators accelerate particles purely to smash particles into smaller pieces effectively. But is it also (or even, mainly) because the colossal speeds give experimenters a relatively long time to observe the results of a collision?
I doubt I can explain it well, and that may be why I don’t understand it, but ever since my school days I could not get how it is that everything is relative, but the clock here on Earth is the one going “faster” (which, as Dallas_Jones has explained, is not the correct way to state it). I know that experiments show it and that it therefore is so, but why does the “stationary” twin/piece of wood age more than the other? Should not, if we changed the frame of reference to the other twin/piece of wood, the aging speed be reversed? It is absurd, of course, but it seems to me that both twins/pieces of wood should age faster and slower than the other simultaneously. Or interchangeably. But how could our decision to declare this or that the frame of reference bring that difference? It doesn’t, I know, but what I don’t understand is why.
I’m not a particle physicist but I believe it’s entirely because the high velocities are necessary to get lots of energy and interesting results. If the lifetime was shorter we could place the detection apparatus closer.
Is that the reason one “counts” as stationary and the other not (excuse the sloppy nomenclature, I hope what I mean is clear)? That we only have one frame of reference and the departing accelerating object has many?
Or at least two. Yeah, that’s pretty much it: You can do the calculations in any frame of reference you want, but you have to do them all in the same frame. That frame could be the Earth frame, or it could be the outbound traveling frame, or it could be the inbound traveling frame. Or, I suppose, if you’re masochistic, some other frame entirely. But you can’t pick “the traveling wood’s frame”, because that’s not all the same frame. And no matter what frame you pick, you’ll get the same answer for which one is older, at the point they meet up again, and by the same amount.