He's BS-ing you to the extent that an explanation of the fourier transform is not necessary to point this out ("units are relative" - what like length and time are the same thing? then all unit definitions would be circular as length is defined in terms of time at present. is mass also length? can you give my height, weight, and age in one number and define each as the same number in different units? =) ). I'll be specific though, anyway. The fourier transform of a scalar number is simply not defined (no such thing as a fourier transform of a distance, for instance). Typically fourier transforms give you a function of frequency for every function of time or of space. Under certain conditions, where there is a relationship between spatial frequency and temporal frequency (like waves propagating in a nondispersive medium here wavelength*frequency = speed of waves) you can then get a function of time for any function of space using a fourier transform, indirectly. But this is a special case, involves functions, not numbers, and this fourier transform of the original function is NOT THE SAME as the original function, so it's irrelevant to your original argument. So your friend is screwing with you.

Have a good one 

Does this statement make any sense?
I am iOS developer. I made an application for chat which required registration for go into app.
In registration screen, it require DATE OF BIRTH. Apple reject my app for more than 3 times because of DATE OF BIRTH field. I have told them that into our privacy policy we described that user's age must be more than 17 so, we need to add this field for date verification.

But, still they are rejecting my app. 

Please help me.
