Employment clause restricting future employement

No. And you are right, the clause violates your constitutional rights. In fact, even if your terms of employment did mention the names of competitior companies, the clause would still be violative of your constitutional rights.

I dont think any company will take the matter to court if you joined a competitor company. But I believe most companies in the same business have this agreement among themelves not to hire somebody from a competitor company with in a specified period

You have your right to earn your livelihood and you can not be bonded to drop your right to earn livelihood.

Is their any arbiteration clause also attached to this clause?

no such clause is illegal.