Jump to content

Is there such thing as infinite speed?


needimprovement

Recommended Posts

No because nothing can be faster than the speed of light, which is finite.

 

That's a commonly used summary which unfortunately has been oversimplified to the point that it's wrong. It depends on what you mean by "nothing" (or "something") and "be." Mass cannot travel at c, and massless objects travel at c. But phenomena that are not causally connected can happen faster than c, e.g. a lighthouse sweeps out 2pi radians in a unit of time, and will make a streak of light on a distant target. If you are far enough away, that streak will be faster than c. This is not in violation of relativity.

Link to comment
Share on other sites

To say it in the words of a famous physicist:

Nothing is impossible. Not if you can imagine it. That's what being is a scientist science forum member is all about.
Defining terms as they happen to suit your idea helps a lot in that (c.f. Swansont's reply).
Link to comment
Share on other sites

It maybe possible to construct a notion of infinite speed, but it will not be a relativistic speed as defined in special relativity. That is, it won't appear as a speed between co-moving inertial frames. Even then, infinity is something that cannot be measured and thus any infinite speed will not be something measurable. So maybe arbitrarily fast, but finite speed are better.

Link to comment
Share on other sites

  • 3 weeks later...

It might be worth pointing out that in special relativity in light-cone coordinates you can have infinite speeds. In these special coordinates things start to look more like non-relativistic mechanics and QFT looks more like quantum mechanics.

 

But note, no Lorentz transformation can get you from an inertial set of coordinates to light-cone coordinates. There is no violation of the basic rules of special relativity here, just a peculiar choice of coordinates.

 

I am sure other "weird" choices that give seemingly crazy results exist. One must take care when comparing this to statements in inertial frames.

Link to comment
Share on other sites

As all experiences happen in the brain is it sufficient to say that if a brain experiences something it has happened, if so then infinite speed is possible because I have experienced infinite speed.

 

I'll explain.

 

A long time ago I had some rye bread sitting on the side in the kitchen, unfortunately it had gotten a bit mouldy but as I was very hungry I ate it any way. Later that night I went to bed and had a very interesting dream.:rolleyes:

 

Anyway...

 

In my 'dream' I was falling down a long tunnel, so long I couldn't see the end. As I fell I got faster and faster until I reached the speed of light. There was a big flash as I went through the light barrier and I enjoyed this feeling for a moment. Seriously, experiencing that accceleration for that amount of time and travelling at that speed was exhilarating. Over the next second or so I accelerated from the speed of light to infinitely fast, during this acceleration my field of vision expanded to include everything behind me as well as everything in front of me and before I knew it I no longer existed as a point moving along a trajectory but existed at every point along that trajectory simulataenously. The path I travelled took me back to the point I started so it was a big loop but I existed along the entire lenght of it.

 

So in that respect there is infinite speed.

 

And if anyone offers you mouldy rye bread, just say NO!

Link to comment
Share on other sites

Why only 2?

 

indeed

 

It might be worth pointing out that in special relativity in light-cone coordinates you can have infinite speeds. In these special coordinates things start to look more like non-relativistic mechanics and QFT looks more like quantum mechanics.

 

But note, no Lorentz transformation can get you from an inertial set of coordinates to light-cone coordinates. There is no violation of the basic rules of special relativity here, just a peculiar choice of coordinates.

 

I am sure other "weird" choices that give seemingly crazy results exist. One must take care when comparing this to statements in inertial frames.

 

I learned something today. Thank you.

Link to comment
Share on other sites

Your two recent answers are contradicting each other. Which position are you taking — that infinite speed only connects two points along a trajectory, or all points?

 

I took it as two points meaning more than one point ie any number of points you care to think of.

 

So is it possible to exist in two places at the same time?

Link to comment
Share on other sites

If you can exist at any two points along a trajectory because of infinite speed, I'm not seeing why it's restricted to two (or even more), rather than all points along all trajectories, which was rejected.

 

 

So is it possible to exist in two places at the same time?

 

That's a bit of a loaded question. You can have a quantum superposition of locations, but to say whether that counts depends on what "exist" means.

Link to comment
Share on other sites

Your two recent answers are contradicting each other. Which position are you taking — that infinite speed only connects two points along a trajectory, or all points?

 

That infinite speed connects all points along a (infinite) trajectory.

I suppose that if infinite speed were to exist, we would have some difficulty to identify the concept of uniqueness.

Link to comment
Share on other sites

Why couldn't the trajectory include all points?

 

What do you mean by "all points"?

_All points of space?

 

........

After a night of cogitation, I wonder if this conversation has a meaning at all.

 

For example, something moving at infinite speed would be everywhere at a single instant (not regarding what "everywhere" really means), but the same "thing" at the next instant would be gone...infinitely far away...

Link to comment
Share on other sites

If you can exist at any two points along a trajectory because of infinite speed, I'm not seeing why it's restricted to two (or even more), rather than all points along all trajectories, which was rejected.

 

Isn't 'all trajectories' a bit confusing, there's only one trajectory which either includes all points or some points.

 

You can imagine your journey would describe a huge circle as you travel around the universe and you end up back where you started, you would exist at all points on a line. Alternatively you can imagine travelling through all points in the universe, and therefore existing at all points, before returning to the point you started.

 

So is it possible to exist in two places at the same time?

 

That's a bit of a loaded question. You can have a quantum superposition of locations, but to say whether that counts depends on what "exist" means.

 

I only ask because I heard that there is nothing in physics that forbids time travel but if you travelled in time you, and all the atoms you are made of, would exist in two places at the same time.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.