You don't lose experience ever. When you die you either clone at the closest facility, which incurs a wound penalty (stats bars shrink permanently until you get it fixed) or you can clone at the last place you chose to be cloned with no penalty. If you didn't insure your items you'll have to run to your corpse to get them.
There are two kinds of PvP: duel and faction. Duels can be against anyone, anywhere, and is consentual. Faction PvP is also possible anywhere and is non-consentual (kinda). You have to join either the Empire or Rebellion, and must be "overt" (vs. covert) for other people to know you are part of that faction and become attackable.
Something that is really cool about combat in this game is that you have to be "deathblowed" to die. Most animals merely incapacitate you so you are just knocked out for like a minute-and-a-half. Same with PvP. In a duel, for instance, you will knock your opponent out, then you can choose whether or not to kill him. The duels I had were honorable no-deathblow duels where you aren't supposed to deathblow the opponent.
I think this is a great feature. Because of the way combat is set up in this game we are free to do things such as have "fight clubs" and "cock fights" without fearing any penalties from the game system (such as "notoriety" or "alignment"). We'll be able to practice dueling and PvP on each other without fear.
In fact, belonging to the Empire, we'll be able to have NPC "cock fights"

. When your faction "pet" (ie NPC that you hire with faction points) dies, you can call him from your datapad immediately and at full health. This means there is no risk having NPCs fight! You can only call them if you are in a camp, a city, or are near a building you have access to.