"Can you write a script that makes the player's head turn in the direction of the camera and simulates real human head physics?"

I can provide you with a script that makes the player's head turn in the direction of the camera. However, simulating real human head physics is quite complex and may require a more advanced implementation.

Here's a script that makes the player's head turn in the direction of the camera:

```lua
-- Local Script
local Players = game:GetService("Players")
local RunService = game:GetService("RunService")

local player = Players.LocalPlayer
local camera = workspace.CurrentCamera

function updateHeadRotation()
    local character = player.Character
    if character and character:FindFirstChild("Head") and character:FindFirstChild("Humanoid") then
        local head = character.Head
        local humanoid = character.Humanoid
        local rootPart = character.HumanoidRootPart

if humanoid.Health > 0 then
            local lookVector = camera.CFrame.lookVector
            local rootPartLookVector = rootPart.CFrame:VectorToObjectSpace(lookVector)
            local angle = math.atan2(rootPartLookVector.X, rootPartLookVector.Z)
            local headRotation = CFrame.Angles(0, angle, 0)

head.CFrame = rootPart.CFrame * headRotation * CFrame.new(0, head.Size.Y / 2, 0)
        end
    end
end

RunService.RenderStepped:Connect(updateHeadRotation)
```

This script will make the player's head turn in the direction of the camera, but it does not simulate real human head physics. Implementing realistic head physics would require a more advanced understanding of Roblox physics, constraints, and animations.