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Relativity Explained in Haiku

Light moved faster than c? What experiments were those? I ask because doing so would imply quite a space-time wrinkle, as each point's reality cone extends outward at c. Light moving faster than that could be used to change the flow of time by monkeying up causality.
 
You had not heard of
Experiments about light
Moving really fast?

It's true; some light can
Move superluminally.
This link might help you.

As for special rel:
It's not affected by this.
I do not get why.
 
Seems to me, rwald,
It's all just a clever trick.
The explanation?.....

We have a light pulse
Composed of several waves.
Each travels at c.

The summation wave
Seems to travel above c
And here's how it's done:

Pulse passes through gas
- Laser-soaked cesium gas -
(If you need to know).

The component waves
Rephase as they pass through it.
And then they summate.

But the rephasing
Causes the summation wave
To appear early.

So it only seems
To travel above light speed.
Seems to me at least.
 
You've got it, BJ.
Rephasing takes place closer
Than it would if no air

Existed between
The pulse's starting point, and
Where they do with gas.

It is not really
Faster than light travel, no,
But instead just a

Change in location
Of where the pulses rephase;
Thank you very much.

Edit to add this:
I really suck at Haiku.
I'll leave it for you.
 
Domo Arigato, Rwald-san

Hawking is so smart
I cannot understand him.
This is much better.
 
You're right, BillyJoe;
It's not really FTL.
It just "looks" like it.

Actually, when I
Heard of these experiments,
I didn't get them.

I saw that people
Who know far more than I do
Said it minds Einstein.

I guess that I will
Have to take your word for it.
If it's true, you'd know.
 
rwald said:
Relativity.
First, there's "special;" it
Has no acceleration
Only about speed.
Click to expand...

This is a common
misunderstanding many
people often have

special rel. really
can do acceleration
though it's not easy

Problems arrise not
from acceleration, but
only from gravity
 
However, if I
Understand general rel,
They are both the same.

Acceleration
And gravity, that is; they
Can't be distinguished.
 
gravity is like
acceleration if it
is uniform, but

Gravity is not
globally uniform, so
to deal with that fact

we use general
relativity, which can
explain curv'd space-time
 
Ah, hell with it. I can't keep up this Haiku stuff. But here's the skinny:

1) special relativity can handle acceleration.
2) uniform gravity is just like acceleration.

One might come to the conclusion that special relativity should therefore be able to handle gravity. But it can't. Why? Well, consider two people on the opposite sides of the earth. Special relativity would need to treat both of them like they're accelerating away from each other, but they're clearly not. The problem is that the caveat of the gravitational field being uniform clearly doesn't hold here.

What general relativity does is use the concept that uniform gravity is just like acceleration in order to some up with a theory (really a GEOMETRY) to explain space-time.

People always obsess about this idea that gravity is just like acceleration, but I think the better way of looking at it is that any freefall is an inertial reference frame, that is, a free-falling object is NOT accelerating. In order for that to make sense, you need a curved space-time, so that "straight" (unaccelerating) trajectories through space-time looked curved to our naive Euclidean ideas of space.

So special relativity can handle acceleration. But only in a flat space-time. Once you throw in curvature from gravity, it becomes insufficient.
 
OK, let me see
If I understand what you
Are trying to say:

Special rel works with
Constant acceleration;
Nothing more than that.

Gravity's not like
Constant acceleration;
It's like it changes.

So, gravity and
Changing acceleration
Need general rel.

I guess that makes sense.
Though I don't get why special
Can do constant a.

I guess I should read
Six Not So Easy Pieces
By Richard Feynman.

I have started it,
But the math got difficult.
I must persevere.
 
Thank you, BillyJoe.
That site was informative.
Let me try again:

Special rel always
Assumes that space-time is flat.
This is the difference.

Using special rel,
Acceleration is said
To be absolute.

You can't know your speed,
It's relative; not so with
Acceleration.

However, when you
Use general rel, all is
Fully relative.

That's because space-time
Contorts with gravity and
Acceleration.

You can't say whether
You are accelerating,
Or on a planet.

Special rel lets you
Know acceleration; in
General you can't.

(I hope that last verse
makes sense to most; it's not one
Hundred percent clear.)

Anyway, I hope
This clears up any problems.
If not, than reply.
 
bumped, as this was enjoyable to read for me

In case any one missed it


Question posed in a chat room:

if you spin a sphere really fast can you create a gravity well that you can push?

my response:

tough question.... have to consider how relativilty applies
the spinning sphere would warp space /time as its spin accelerates

Angreifen's response> yes it is krate... but if you can do so you could probably create a new propulsion system

me: for a propulsion system the gravity well can not be formed around the vessel and expect it to move... the well would have to be formed ahead of the vessel

I am having some trouble wrapping my mind around this ....
 
I think you might be right PPG, but for a definitive answer perhaps you'll need to direct some of the physicists on the board (such as Stimpson C Cat or Tez) to this thread.
 
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