2 people start a business together. If one of the partners send the other partner Dissolution papers does that mean the partnership is over?

The answer is, it depends on the type of business organization; the law under which the organization was formed; and any agreement between the business owners. State law will govern the conditions under which a business organization can be dissolved, although it may allow the business owners to modify the law to some extent. You need to find out several things: (1) is this a partnership or some other type of business organization such as corporation or limited liability company; (2) what state law governs the business organization; and (3) did the business owners have a written agreement that sets out conditions for dissolution. Once you determine this, you can find out if sending dissolution papers is adequate to dissolve the business organization. Then, you need to consult the laws/agreement to determine how to "wind up" the business.