FTL without paradoxes?

[Dave]

Then the consensus is that, to answer the OP question, no, you can never have FTL without paradoxes, because the paradoxes are a result of FTL being impossible. However, if you want to have FTL in your fiction, just don't raise the question of paradoxes, and if you never mention them then you can pretend they are not there.

 

[Onyx]

Then the consensus is that, to answer the OP question, no, you can never have FTL without paradoxes, because the paradoxes are a result of FTL being impossible. However, if you want to have FTL in your fiction, just don't raise the question of paradoxes, and if you never mention them then you can pretend they are not there.

Correct. If you want your hero to fire a gun that has seemingly no recoil but sends his opponents careening through the air - same idea applies; physics is on hold for the sake of drama.


OR, you deal with FTL the same way you deal with "realistic" time travel - by using similar explanations that make time travel possible, like access to the multiverse or some inability to interact with the universe after FTL.

 

[tinkerdan]

Okay im out of here

 

[Onyx]

I'm not a physicist--definitely don't have a degree in that direction; however::
The cone of light and causality is all based on the speed of light being the fastest speed that anything can travel. If something could travel faster than light then we would prove mostly that we were wrong about light and there is something faster. That neither messes with time nor disrupts causality--it just shifts what we know now to what we will know then.

Physics doesn't change; our understanding does.

We have observable phenomenon that suggest faster than light; however most of those are explainable and are illusions that actually fit present understanding and the few that aren't yet explainable are such that they are not usable in any means or form of communication or any other uses.

As to frames of reference--all frames in the universe are moving and the speed of light is the same for all of those frames of reference any other frame such as a fixed frame are presently unattainable as much so as a pure vacuum is unattainable. And if we could create a perfect vacuum we might determine that the potential speed of light is greater than it is in our not so perfect vacuum from which we've measured it.

On a lighter note it's been said that nothing is faster than the speed of light.

And from that, in an expanding universe, if we could go the the very edge of the universe we could look outward and observe nothing: traveling away from us faster than the speed of light.

Your post is an example of what happens when you don't actually buy into the relativity universe and see it instead as a big 3D cube of space with speed limit signs posted everywhere.

In actuality, there is no "edge of the universe" to travel to any more than there is edge of the world. Light travels at the top speed of the universe because it has no mass so it can go to 100%, but it is just obeying the same laws as everything else that causes the universe to curve the way it does.

There will come a day when we find a better way of understanding things, but right now it appears that acceleration, mass, distance and time are so incredibly intertwined with each other that going "the speed of light" is identical to saying "take up no distance" and "having time stop". So exceeding the speed of light implies things like negative mass, negative space and time running backwards.

 

[BAYLOR]

Your post is an example of what happens when you don't actually buy into the relativity universe and see it instead as a big 3D cube of space with speed limit signs posted everywhere.

In actuality, there is no "edge of the universe" to travel to any more than there is edge of the world. Light travels at the top speed of the universe because it has no mass so it can go to 100%, but it is just obeying the same laws as everything else that causes the universe to curve the way it does.

There will come a day when we find a better way of understanding things, but right now it appears that acceleration, mass, distance and time are so incredibly intertwined with each other that going "the speed of light" is identical to saying "take up no distance" and "having time stop". So exceeding the speed of light implies things like negative mass, negative space and time running backwards.

What about Hyperspace ?

 

[Travis Woodward]

Thanks everyone. I'm still not quite sure where I've gone wrong in my reasoning (and I want to understand!), but for now I'll take your advice and just write the story.

At some point though I suspect I'll come back once I've drawn up some light cones that illustrate what I'm getting at (as I don't think I'm explaining myself very well!) and hopefully someone will be able to explain to me where I've gone wrong.

 

[Onyx]

What about Hyperspace ?

What about phlogiston?

 

[Onyx]

Thanks everyone. I'm still not quite sure where I've gone wrong in my reasoning (and I want to understand!), but for now I'll take your advice and just write the story.

At some point though I suspect I'll come back once I've drawn up some light cones that illustrate what I'm getting at (as I don't think I'm explaining myself very well!) and hopefully someone will be able to explain to me where I've gone wrong.

As I tried to say earlier, your particular example doesn't appear to violate causality. But how do you explain how only the one set of wormhole exists and others that would paradoxically interact with them cannot exist?

I didn't catch where you explained what's preventing a fast moving set of observers from making them as well.

 

[BAYLOR]

What about phlogiston?

Long discredited theory and by mentioning it by implication are saying that you think Hyperspace is nonsense ? or am I wrong.

 

[Onyx]

Long discredited theory and by mentioning it by implication are saying that you think Hyperspace is nonsense ? or am I wrong.

"Hyperspace" either refers to the fact of dimensions greater than 3, or it refers to a fictional idea about how you could travel faster than light.

The fictional idea isn't discredited, it is made up, like Transporters, Valar or Bobbles. It isn't the result of a scientific theory and hasn't been tested as such, but a fictional device like Adamantium.

 

[BAYLOR]

"Hyperspace" either refers to the fact of dimensions greater than 3, or it refers to a fictional idea about how you could travel faster than light.

The fictional idea isn't discredited, it is made up, like Transporters, Valar or Bobbles. It isn't the result of a scientific theory and hasn't been tested as such, but a fictional device like Adamantium.

Your obvious very well verse and read in the sciences. If you don't mind me asking Are You a science student or scientist ?

 

[Onyx]

Your obvious very well verse and read in the sciences. If you don't mind me asking Are You a science student or scientist ?

Nope. Just a guy with a library card and an internet connection.


And just to be clear, I like FTL stories. I like time travel stories, too. I like Crouching Tiger, Hidden Dragon. I just wouldn't enjoy them if the writers invested heavily explaining how the physics of each was completely Kosher, and in offering an explanation say things that are easily disprovable. Suspension of disbelief requires that if you want to present something fantastic like Superman flying, you at least hide the wires.

 

[BAYLOR]

Nope. Just a guy with a library card and an internet connection.

Well read then . Okay .

 

[goldhawk]

What about Hyperspace ?

Violating the speed of light, no matter if it's hyperspace or wormholes or whatever, means you can time travel. So why hasn't anyone from the future dropped by to say hello?

 

[BAYLOR]

Violating the speed of light, no matter if it's hyperspace or wormholes or whatever, means you can time travel. So why hasn't anyone from the future dropped by to say hello?

Because time travel into the past is impossible ?

 

[goldhawk]

Because time travel into the past is impossible ?

Time travel leads to such things as the Grandfather Paradox.

 

[BAYLOR]

Time travel leads to such things as the Grandfather Paradox.

Yeah I know that one.

 

[goldhawk]

Yeah I know that one.

So, if time travel is possible, how would this be resolved?

 

[BAYLOR]

So, if time travel is possible, how would this be resolved?

Alternate timeline?

 

[Onyx]

Alternate timeline?

Which is what I was getting at in post #42. You make the jump, but it doesn't violate causality because you're no longer in the same universe. In that circumstance time travel and FTL are actually jumps to different universes at times or locations different than the start point in the previous one.

Which offers some obnoxious possibilities for fiction writers.