# If we could travel at light speed, would travel be 'instantaneous' for us??

by Bad_Wolf 34 Replies latest social current

This might be confusing to think about.

We know that as you approach the speed of light, time slows down, if you were in a spaceship, time goes by quicker on earth.

We also know that distances between planets and such are measured at 'light years'. Meaning that light from a planet if it's 1,000 light years to another planet, would take 1,000 years of our time to reach it.

We also know that photons don't age (which travel at light speed)

Now, if you were able to travel at the speed of light, and you were to go to a planet 1,000 light years away, would you/your body/the spaceship 'age' 1000 years to get there? Or once the spaceship hits light speed, while it takes 1,000 years of our time to reach that planet, would the person and the spaceship itself stop aging and for them that 1,000 light year journey feel like it was instantaneous?? (would definitely create a conundrum if that technology existed then on how to stop or slow down)

• ##### blondie

Since we are surmising, what about wormholes, they seem to transcend spacetime, or how about warp drive. I always wondered about the concept that time would ran faster for the person on earth than the person traveling in space so that when the person returned from space, they would be younger than the person who stayed on earth (of course assuming they were both the same age at the start).

If humans could figure out the science around the current barriers, may be things could be resolved. Right now, people are looking at what is currently known, not what the future might bring.

• ##### Anders Andersen

Forgetting the part that we would need literally an infinite amount of energy to get to the speed of light in the first place, time would stand still for someone travelling at the speed of light. So from the traveller's point of view, they'll arrive at their destination at the very moment they hit the speed of light.

But let's say the traveller reaches a speed very close to the speed of light, and travels a 1000 years from our point of view. Then in their frame of reference they arrive much sooner, perhaps after their calendars, clocks and bodies have progressed 50 years.

This is also one of the (currently hypothetical) problems of interstellar travel: even if we manage to reach speeds close to the speed of light, and manage to travel to another star and maybe even back....the travellers may have survived the trip....but here on Earth a much, much larger time has passed. When the travellers return, their family and colleagues have already died millenia ago. Perhaps even humanity doesn't exist anymore. A strange thing to contemplate. Someone should make a movie out of that :-)

I guess the best way to appear to be travelling close to the speed of light is by being able to exploit 'wormholes', time-space curves, etc.

Whatever the answer is it'll be easier to understand than the generation explanation.

• ##### sir82

Someone should make a movie out of that

I'm guessing you've seen "Interstellar". I can't think of another movie which addresses this issue quite so well.

• ##### smiddy3

What about "The Time Machine" with Rod Taylor ?

• ##### Diogenesister

Anders can you explain the mathematical symbols on the chart at all, please? I understand square root, but I don’t know what the other symbols represent.

edit don’t worry I clicked the link, thank you!

• ##### sir82

What about "The Time Machine" with Rod Taylor ?

Rod Taylor returned to his own time period. "Real" light speed "time travel" is one-way - once the time has passed, you can't go backward.

Come to think of it, the original "Planet Of the Apes" kinda sorta dealt with this, but not as "realistically" as "Interstellar".

• ##### Anders Andersen
I'm guessing you've seen "Interstellar". I can't think of another movie which addresses this issue quite so well.

Huh....yeah I saw that movie, but couldn't remember anything related to time dilation (or anything beyond Sandra Bullock outside a space station).

So I checked out the movie's plot. I found out that Sandra starred in Gravity not Interstellar, and the general description of rang enough bells to remember the time dilation stuff somewhat. I guess it's time to view that movie again.

• ##### stan livedeath

probably meet yourself coming back