Does time dilation only affect matter that has mass?

Milfeulle
Messages
3
Reaction score
0
Does time dilation only affect matter that has mass?

For example, A spaceship is 1 light year away from Earth at rest. It sent out a radio wave to Earth then travels at 99.99% of the speed of light. On Earth, from our perspective, we will receive that radio wave 1 year later but the spaceship arrives 70 years later. If that spaceship speed up to 99.999999% of the speed of light, it will take 7000 years from our perspective to see that spaceship.
As a result, from our perspective, the faster that ship travels, the later it arrives, how does that makes sense?
 
Physics news on Phys.org
Milfeulle said:
A spaceship is 1 light year away from Earth at rest. It sent out a radio wave to Earth then travels at 99.99% of the speed of light. On Earth, from our perspective, we will receive that radio wave 1 year later but the spaceship arrives 70 years later.
You have the dilation the wrong way round. The spaceship arrives just over 1 year later by Earth's clocks, but 1/70 year later by the ship's own clocks.
 
Ahh I see, I got the wrong way around all this time! Thanks for the reply!
 
DrGreg said:
You have the dilation the wrong way round. The spaceship arrives just over 1 year later by Earth's clocks, but 1/70 year later by the ship's own clocks.

So that means it only took the ship 5.21 days to arrive on Earth (from the spaceship's perspective) ? If so, that means if the spaceship can travel at 99.9999999999999% of the speed of light, it will only takes 1.41 second to arrive on Earth from the spaceship's perspective. It would be almost like... instantaneous travel...?
In another word, From the light's perspective, all that light from the Big Bang 14 billion years ago was already spread out everywhere in the Universe since the beginning and what we're seeing are just the trails it left behind?
 
Last edited:
Thread 'Can this experiment break Lorentz symmetry?'
1. The Big Idea: According to Einstein’s relativity, all motion is relative. You can’t tell if you’re moving at a constant velocity without looking outside. But what if there is a universal “rest frame” (like the old idea of the “ether”)? This experiment tries to find out by looking for tiny, directional differences in how objects move inside a sealed box. 2. How It Works: The Two-Stage Process Imagine a perfectly isolated spacecraft (our lab) moving through space at some unknown speed V...
Does the speed of light change in a gravitational field depending on whether the direction of travel is parallel to the field, or perpendicular to the field? And is it the same in both directions at each orientation? This question could be answered experimentally to some degree of accuracy. Experiment design: Place two identical clocks A and B on the circumference of a wheel at opposite ends of the diameter of length L. The wheel is positioned upright, i.e., perpendicular to the ground...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. The Relativator was sold by (as printed) Atomic Laboratories, Inc. 3086 Claremont Ave, Berkeley 5, California , which seems to be a division of Cenco Instruments (Central Scientific Company)... Source: https://www.physicsforums.com/insights/relativator-circular-slide-rule-simulated-with-desmos/ by @robphy

Similar threads

Back
Top