Open main menu
Home
Random
Log in
Settings
About Conservapedia
Disclaimers
Conservapedia
Search
Changes
← Older edit
Newer edit →
Quantum mechanics
(view source)
Revision as of 21:25, November 22, 2016
938 bytes added
,
21:25, November 22, 2016
Added stuff about probability
Line 47:
Line 47:
Other examples include energy and time, as well as different components of [[angular momentum]].
Other examples include energy and time, as well as different components of [[angular momentum]].
+
+
===Probability===
+
+
The probability a particle is found in a certain region <math>a < x < b</math> can be described as:
+
+
<math>
+
p(a < x < b) = \int^b_a |\Psi (x,t)|^2 dx
+
</math>
+
+
provided that the wavefunction is normalised:
+
+
<math>
+
\int^\infty_{-\infty} |\Psi (x,t)|^2 dx = 1
+
</math>
+
+
In general, the expected value of a measurement of a quantity <math>Q</math> can be described as:
+
+
<math>
+
\langle Q \rangle = \int^\infty_{-\infty} \Psi^{*} \hat{Q} \, \Psi dx
+
</math>
+
+
where <math>\hat{Q}</math> is the [[operator]] associated with the quantity <math>Q</math>. For example the position operator is simply <math>x</math>. The [[momentum (physics)|momentum]] operator is:
+
+
<math>\hat{p} = \frac{\hbar}{i} \frac{\partial}{\partial x}</math>
+
+
so that the expected momentum is:
+
+
<math>\langle p \rangle = \int^\infty_{-\infty} \Psi^{*} \hat{p} \, \Psi dx = \frac{\hbar}{i} \int^\infty_{-\infty} \Psi^{*} \frac{\partial \Psi}{\partial x} dx
==Interpretations==
==Interpretations==
PeterIceHockey
122
edits