Objects cannot have a velocity > c. But what about acceleration?

c is a velocity. Acceleration is acceleration. The question can you have an acceleration greater then c is meaningless.

 

Acceleration is acceleration and velocity is velocity. They are different things, measured in different units. Talking about "an acceleration greater than c" is like talking about "a sound greater than green".

 

The theory of special relativity does not in itself limit the acceleration of a physical object, but there will of course, depending on the situation, be practical limits as to how much acceleration you can give an object (power requirements, heating, maximum shear stress, and so on). I would think that you will be able to get some of the highest practical obtainable accelerations experiments involving particle physics, or perhaps in constructions like the railgun.

 

I agree to all the reserve of the preceeding posts.
An acceleration greater than c in magnitude only means that the object would reach the spped of light from rest in less that 1 second. That's all… And that's impossible.
Now, as a thought experiment, calculate the acceleration of an object which goes from rest to, say, 0.9c in 1/10 of a second. Well, that's trivial : the acceleration is already 9c m.s-2. Which is what you mean by “acceleration greater than c” :)

 

Don't fool yourself… Obviously, the question of the OP was “Is an acceleration of more than 299792458 m.s-2 possible ?”. At least, that's how I understand it…
The answer is yes. His choice of words was poor, that's all :)

PS : I was saying that it is impossible for a material object to reach the speed of light.

 

Why is that more obviously correct than "Is an acceleration of more than 1 billion km/hr^2 possible ?”

 

OK, ok… Maybe I misanderstood the OP… I don't know :)
Let's wait for sakodo to clarify :)