Ive received a fine in Lausane metro but didn't sign a paper (probably he just forgot about the signature).
So if there is no signature is the fine and my personal info in their system?
I respect Swiss law but 100 chf is pretty much for a student waiting for the salary.

A quicl search will reveal loads of historical threads about this, and in all cases the answer is the same - you got caught, accept the penalty, live and learn.

I don't know why you think the lack of a signature might be relevant, but it won't make any difference, you'll still need to pay up.

A signature is irrelevant. Transports publics lausannois only needs to see an ID.

"Selon la LTV (art. 20), si vous ne pouvez présenter un titre de transport valable, vous devez attester de votre identité et payer un montant forfaitaire ainsi qu'un supplément."

If no ID is provided, they'll establish your identity at a cost of 25 CHF per 15 min (100 CHF/hour).

"Lors du contrôle du titre de transport, le défaut de présentation d’une pièce officielle d’identité engage des frais de recherche et d’identification facturés CHF 25.- par quart d’heure entamé."

https://www.t-l.ch/contact/conseils-...ontrole-des-tl

You have the following options:

1. pay 100 CHF now
2. pay 140 CHF when the unpayed fine goes to the Office de Poursuites
3. pay even more later.

And buy a monthly ticket if you travel often?

... and take this as a learning experience.

By paying for your rides.