# B Traveling backwards through time: clarification please

#### PAllen

Actually, it's impossible to show. I suspect what you mean is that you can use the equations of special relativity to show it. But those equations are built on a foundation that contradicts your premise!

The foundation of special relativity is that light speed is invariant. You start out stating "if you do faster-than-light". That violates the foundation that light speed is invariant. Therefore whatever conclusions you draw are bound to be incorrect.
That's not true. Hypothetical existence of tachyons in no way affects the invariance of light speed.

#### Mister T

Gold Member
That's not true. Hypothetical existence of tachyons in no way affects the invariance of light speed.
I took the OP's reference to "you" as a reference to material objects that currently have a speed less than $c$.

Mentor

#### PeterDonis

Mentor
Some off topic posts have been deleted. The thread has run its course and will remain closed.

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