Because, if it is true then the conditions of Special Relativity are broken which means you can't use SR to begin with. Unless you only want to accept the theory partly, but then who are you to choose which parts are to be accepted and which not? 

I don't think tachyons are inconsistent with SR. Which principles do you believe are broken by this?

No one knows for certain what the consequences would be, true. I will rephrase it as one of the possible consequences is that signalling backwards could be possible. It depends on the exact mechanism of how they are travelling faster than c.

Most of SR would still hold even if this somehow invalidates it, because all the experiments we've done to confirm SR still stand.

I don't want to talk about tachyons. But if they were tachyon neutrinos, then this whole debacle would've been more about QFT than Einstein's SR.

Do you agree that time travel is a possible consequence though?

Link to official retraction please.

Or is this just another speculative blog by someone without access to the details of the experiment?

I am waiting for a peer-reviewed paper that either confirms or denies this observation.

--

"But travel back in time?

No I don't agree.

You explain to me how that would work and I will gladly listen..."

Dismissing something because it sounds absurd is not science. Look at the double slit experiment. I don't know how it would work, but there is nothing wrong with the concept as far as contradicting what we observe already.

You have the right spirit. I expect something soon. But that's the best explanation I've heard and it comes from insider sources hehe.

 I should probably ask my university supervisors...

"Dismissing something because it sounds absurd is not science. Look at the double slit experiment. I don't know how it would work, but there is nothing wrong with the concept as far as contradicting what we observe already."

My question would be how you would accelerate a human being to greater than c since we have tons of experience that it isn't even possible for particles as light as protons and neutrons.

Or were you only referring to 'signalling back in time'? For this I also disagree. Mostly because we haven't seen any signals yet but also because of HUP. Perhaps you can give me a peer-reviewed paper that develops the idea of time-travel?

Yeah, signalling. The only work on time travel I know has been purely mathematical, setting out the conditions for time travel to occur theoretically (tachyons, rotating cylinders of infinte length, matter with negative mass or negative energy if we found any, and so on). Of course we haven't observed anything like that, I'm just not prepared to rule it out.