then we cant breakthrough time
Yes and No. The norm, of course, is that we travel forward in time at a constant rate within our local spacetime frame of reference; but when we move relative to an object outside our frame of reference, we travel forward in time relative to that object. We don't usually have evidence of this because the effect is very close to zero at day-to-day, earthbound speeds, but it becomes significant as an object's relative velocity approaches that of light (as do particles at LHC). So, travelling forward in time is a reality. Going backward in time is the problem; it's considered by many to be impossible for reasons of both science and philosophy. Although there are serious ideas about how it might be achievable, there's no foreseeable feasible experiment.
Albert Einstein say nothing can faster than light
Right. One way to see it is: as an object approaches light velocity (called 'c'), it increases in mass. So it requires ever increasing energy to accelerate it. If it could reach c, it would have infinite mass, and so would have required infinite energy to do so.
