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Neutrinos has three flavours, but we can simply this to a spin-1/2 system with two flavours to show that neutrinos oscillate between their states.
Significance
Coming soonDerivation
The energy of a neutrino is $$\begin{align*} E&=\sqrt{m^2c^4+p^2c^2} \\ &\approx pc + \frac{m_ic^2}^2{2pm} \end{align*}$$.Assume that $v_e$ and $v_{\mu}$ are quantum states of a spin-1/2 system. Then the state of a neutrino is a linear superposition of eigenstates of the Hamiltonian (energy) $|v_1\rangle$ and $|v_2\rangle$ with respective energies $pc+\frac{m_1^2c^4}{2pc}$ and $pc+\frac{m^2_2c^4}{2pc}$. Then we can write $|v_e\rangle$ and $|v_{\mu}\rangle$ in terms of the possible measurements of energy for $$\begin{align*} |v_e\rangle &= a|v_1\rangle + b|v_2\rangle \\ |v_{\mu}\rangle = c|v_1\rangle + d|v_2\rangle \end{align*}$$ We initialize the system in $|v_e\rangle$. Then the probability of a change in flavour is the same as the probability of a spin flip, which means $$\begin{align*} \text{Prob}_{v_2\to v_{\mu}} \porp \sin^2[\frac{E_1-E_2}{2}t] \end{align*}$$ which means that $$\begin{align*} E_1-E_2\prop(m_1^2-m_2^2), \end{align*}$$ which neutrino oscillations are proportional to the difference of the squared mass of neutrios mass eigenstates.
Associated Concepts
Coming soon
Neutrinos has three flavours, but we can simply this to a spin-1/2 system with two flavours to show that neutrinos oscillate between their states.
Significance
Coming soonDerivation
The energy of a neutrino is $$\begin{align*} E&=\sqrt{m^2c^4+p^2c^2} \\ &\approx pc + \frac{m_ic^2}^2{2pm} \end{align*}$$.Assume that $v_e$ and $v_{\mu}$ are quantum states of a spin-1/2 system. Then the state of a neutrino is a linear superposition of eigenstates of the Hamiltonian (energy) $|v_1\rangle$ and $|v_2\rangle$ with respective energies $pc+\frac{m_1^2c^4}{2pc}$ and $pc+\frac{m^2_2c^4}{2pc}$. Then we can write $|v_e\rangle$ and $|v_{\mu}\rangle$ in terms of the possible measurements of energy for $$\begin{align*} |v_e\rangle &= a|v_1\rangle + b|v_2\rangle \\ |v_{\mu}\rangle = c|v_1\rangle + d|v_2\rangle \end{align*}$$ We initialize the system in $|v_e\rangle$. Then the probability of a change in flavour is the same as the probability of a spin flip, which means $$\begin{align*} \text{Prob}_{v_2\to v_{\mu}} \porp \sin^2[\frac{E_1-E_2}{2}t] \end{align*}$$ which means that $$\begin{align*} E_1-E_2\prop(m_1^2-m_2^2), \end{align*}$$ which neutrino oscillations are proportional to the difference of the squared mass of neutrios mass eigenstates.
Associated Concepts
Coming soon
FullPage
overview
significance
derivation
associated concepts