Hi everyone! I'm a psychologist form Brazil, so sorry for the bad English and for the lack of knowledge in math!(adsbygoogle = window.adsbygoogle || []).push({});

I ve been trying to understand the Schrodinger equation and, as predicted, it's very hard!

Please, help me with this:

A sine wave function can be written as:

F (x) = sin (x)

And that can be represented as psi.

The the derivative of that function can be written as:

F (x) = cos (x)

And that can be represented as psi dot.

Also, the derivative of psi dot can be written as:

F (x) = - sin (x)

And thats psi with two dots.

So far I understood!

But things get confusing here:

A wave equation can be written as:

F (x) = A sin (2π f x )

Where A stands for the amplitude, 2π f x stands for the period.

But, in this video:

It is stated, at 8 mins, that the correct wave function is, as expected:

F (x)= sin (2π f t)

And that's represented by psi

But the derivative of that is

F (x) = 2π f cos (2π f t)

And not

F (x) = cos (2π f t)

(And that's represented by psi dot)

To make things worst, the derivative of that last equation, psi dot, is represented by

## f (x) = - (2π f)^2 sin (2π f t) ##

And not just

F (x) = - sin (2π f t)

(And that's represented by psi with 2 dots)

Why is that?

Thanks a lot!

**Physics Forums - The Fusion of Science and Community**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# B Wave equation, psi with dots and things like that...

Have something to add?

Draft saved
Draft deleted

Loading...

Similar Threads for Wave equation dots | Date |
---|---|

A Wave equation in free space | Jan 7, 2018 |

A Spheroidal Wave Equation | Dec 15, 2017 |

I Homogeneous Wave Equation and its Solutions | Nov 16, 2017 |

I Wave equation solution using Fourier Transform | Mar 13, 2017 |

A Wave equation in cylindrical coordinates - different expression? | Sep 19, 2016 |

**Physics Forums - The Fusion of Science and Community**