I just brought a new Samsung smart TV and my Apple tv wont work with it

Given the history between Samsung and Apple, I'm not surprised... :=). I'm assuming you have thoroughtly checked the HDMI connection between the Apple TV and the Samsung box.

There is some possibility that the built-in networking on the two devices (wireless portion) is in conflict. If you have control of your router and know what you are doing, you should be able to separate the wireless channels used by the two devices so that they don't walk on each other. I avoided the issue by having ethernet pulled to the locations where my TV's are installed. My Samsung TV's use wireless and the Apple TV is hung on the ethernet, so there is no possibility of a conflict over a wireless channel.

Yes I did the same thing, Ethernet for the ATV and wireless for the Samsung. Apart from anything else, I felt the ATV would be happier with the full speed a hardwired cable affords.